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Sample records for biocompatible upconverting nanoparticles

  1. Single-Component Upconverting Polymeric Nanoparticles.

    Science.gov (United States)

    Thévenaz, David C; Lee, Soo Hyon; Guignard, Florian; Balog, Sandor; Lattuada, Marco; Weder, Christoph; Simon, Yoan C

    2016-05-01

    Low-power light upconversion is a highly desirable feature for a broad range of applications and new materials enabling this process are sought in both bulk and particulate form. Here, the preparation of upconverting nanoparticles is reported from a methacrylic terpolymer bearing diphenylanthracene and meso-phenoxytris(heptyl)porphyrin pendant groups by a microemulsion technique. The use of a terpolymer in which the upconvering dye molecules are covalently attached mitigates some of the drawbacks of triplet-triplet annihilation upconverting nanoparticles made by other techniques, in particular dye leakage from the nanoparticles, and limited control of the sensitizer and emitter concentration within each nanoparticle. Size and morphology of the new upconverting nanoparticles are investigated by dynamic light scattering and transmission electron microscopy and elucidated their upconverting properties by luminescence spectroscopy. PMID:27071664

  2. Upconverting nanoparticles for optimizing scintillator based detection systems

    Science.gov (United States)

    Kross, Brian; McKisson, John E; McKisson, John; Weisenberger, Andrew; Xi, Wenze; Zom, Carl

    2013-09-17

    An upconverting device for a scintillation detection system is provided. The detection system comprises a scintillator material, a sensor, a light transmission path between the scintillator material and the sensor, and a plurality of upconverting nanoparticles particles positioned in the light transmission path.

  3. Quantum Yield Characterization and Excitation Scheme Optimization of Upconverting Nanoparticles

    DEFF Research Database (Denmark)

    Liu, Haichun; Xu, Can T.; Jensen, Ole Bjarlin;

    2014-01-01

    Upconverting nanoparticles suffer from low quantum yield in diffuse optical imaging, especially at low excitation intensities. Here, the power density dependent quantum yield is characterized, and the excitation scheme is optimized based on such characterization......Upconverting nanoparticles suffer from low quantum yield in diffuse optical imaging, especially at low excitation intensities. Here, the power density dependent quantum yield is characterized, and the excitation scheme is optimized based on such characterization...

  4. Role of polymers and surfactants in synthesis of high quantum yield upconverting nanoparticles

    Science.gov (United States)

    Newcombe, Kevin; Yust, Brian

    Rare earth doped fluoride nanoparticles with a size of about 25 nm have been synthesized by either solvothermal or microwave assisted techniques. The role of differing biocompatible polymeric compounds to act as nucleation agents and surfactants, including polyethylene glycol, polyvinylpyrollidone, and polyethylene oxide, in the final size, crystallinity, and optical properties is investigated in depth. These upconverting nanoparticles which can be excited in the near-infrared (NIR) are ideal for biomedical applications because of the low absorption of these excitation wavelengths by soft tissues in the body. Their fluorescence can be used for NIR imaging as well as non-invasive activation of drugs conjugated to the surface for cancer therapy. After optimizing the synthesis parameters, wide angle x-ray diffraction, FTIR, Raman, and Vis-NIR spectroscopy are used to characterize the samples. By varying the polymer added to the precursor solution, we can elucidate the primary mechanisms of interaction during the synthesis process and optimize for the best possible optical properties. Finally, the dependence of the fluorescence intensity on the biocompatible polymer type and concentration will also be investigated.

  5. Biocompatibility of crystalline opal nanoparticles

    Directory of Open Access Journals (Sweden)

    Hernández-Ortiz Marlen

    2012-10-01

    Full Text Available Abstract Background Silica nanoparticles are being developed as a host of biomedical and biotechnological applications. For this reason, there are more studies about biocompatibility of silica with amorphous and crystalline structure. Except hydrated silica (opal, despite is presents directly and indirectly in humans. Two sizes of crystalline opal nanoparticles were investigated in this work under criteria of toxicology. Methods In particular, cytotoxic and genotoxic effects caused by opal nanoparticles (80 and 120 nm were evaluated in cultured mouse cells via a set of bioassays, methylthiazolyldiphenyl-tetrazolium-bromide (MTT and 5-bromo-2′-deoxyuridine (BrdU. Results 3T3-NIH cells were incubated for 24 and 72 h in contact with nanocrystalline opal particles, not presented significant statistically difference in the results of cytotoxicity. Genotoxicity tests of crystalline opal nanoparticles were performed by the BrdU assay on the same cultured cells for 24 h incubation. The reduction of BrdU-incorporated cells indicates that nanocrystalline opal exposure did not caused unrepairable damage DNA. Conclusions There is no relationship between that particles size and MTT reduction, as well as BrdU incorporation, such that the opal particles did not induce cytotoxic effect and genotoxicity in cultured mouse cells.

  6. Dual-excitation upconverting nanoparticle and quantum dot aptasensor for multiplexed food pathogen detection.

    Science.gov (United States)

    Kurt, Hasan; Yüce, Meral; Hussain, Babar; Budak, Hikmet

    2016-07-15

    In this report, a dual-excitation sensing method was developed using aptamer-functionalized quantum dots and upconverting nanoparticles, exhibiting Stokes and anti-Stokes type excitation profiles, respectively. Conjugation of the aptamer-functionalized luminescent nanoparticles with the magnetic beads, comprising short DNA sequences that were partially complementary to the aptamer sequences, enabled facile separation of the analyte-free conjugates for fluorescent measurement. UV-Visible spectroscopy, Circular Dichroism spectroscopy, Dynamic Light Scattering and Polyacrylamide Gel Electrophoresis techniques were used to characterize the aptamer probes developed. The target-specific luminescent conjugates were applied for multiplex detection of model food pathogens, Salmonella typhimurium, and Staphylococcus aureus, in which the fluorescent emission spectra were obtained under UV excitation at 325nm for quantum dots and NIR excitation at 980nm for upconverting nanoparticles, respectively. The dual-excitation strategy was aimed to minimize cross-talk between the luminescent signals for multiplexed detection, and yielded limit of detection values of 16 and 28cfumL(-1) for Staphylococcus aureus, and Salmonella typhimurium, respectively. By employing a greater number of quantum dots and upconverting nanoparticles with non-overlapping fluorescent emissions, the proposed methodology might be exploited further to detect several analytes, simultaneously. PMID:26971274

  7. Chemical sensing with nanoparticles as optical reporters: from noble metal nanoparticles to quantum dots and upconverting nanoparticles.

    Science.gov (United States)

    Deng, Wei; Goldys, Ewa M

    2014-11-01

    A wide variety of biological and medical analyses are based on the use of optical signals to report specific molecular events. Thanks to advances in nanotechnology, various nanostructures have been extensively used as optical reporters in bio- and chemical assays. This review describes recent progress in chemical sensing using noble metal nanoparticles (gold and silver), quantum dots and upconverting nanoparticles. It provides insights into various nanoparticle-based sensing strategies including fluorescence/luminescence resonance energy transfer nanoprobes as well as activatable probes sensitive to specific changes in the biological environment. Finally we list some research challenges to be overcome in order to accelerate the development of applications of nanoparticle bio- and chemical sensors. PMID:25170528

  8. Biocompatibility and Toxicity of Nanoparticles and Nanotubes

    Directory of Open Access Journals (Sweden)

    Xiaoming Li

    2012-01-01

    Full Text Available In recent years, nanoparticles (NPs have increasingly found practical applications in technology, research, and medicine. The small particle size coupled with their unique chemical and physical properties is thought to underline their exploitable biomedical activities. Its form may be latex body, polymer, ceramic particle, metal particles, and the carbon particles. Due to their small size and physical resemblance to physiological molecules such as proteins, NPs possess the capacity to revolutionise medical imaging, diagnostics, therapeutics, as well as carry out functional biological processes. But these features may also underline their toxicity. Indeed, a detailed assessment of the factors that influence the biocompatibility and toxicity of NPs is crucial for the safe and sustainable development of the emerging NPs. Due to the unique structure, size, and shape, much effort has been dedicated to analyzing biomedical applications of nanotubes.This paper focuses on the current understanding of the biocompatibility and toxicity of NPs with an emphasis on nanotubes.

  9. Evaluation of iron oxide nanoparticle biocompatibility.

    Science.gov (United States)

    Hanini, Amel; Schmitt, Alain; Kacem, Kamel; Chau, François; Ammar, Souad; Gavard, Julie

    2011-01-01

    Nanotechnology is an exciting field of investigation for the development of new treatments for many human diseases. However, it is necessary to assess the biocompatibility of nanoparticles in vitro and in vivo before considering clinical applications. Our characterization of polyol-produced maghemite γ-Fe(2)O(3) nanoparticles showed high structural quality. The particles showed a homogeneous spherical size around 10 nm and could form aggregates depending on the dispersion conditions. Such nanoparticles were efficiently taken up in vitro by human endothelial cells, which represent the first biological barrier to nanoparticles in vivo. However, γ-Fe(2)O(3) can cause cell death within 24 hours of exposure, most likely through oxidative stress. Further in vivo exploration suggests that although γ-Fe(2)O(3) nanoparticles are rapidly cleared through the urine, they can lead to toxicity in the liver, kidneys and lungs, while the brain and heart remain unaffected. In conclusion, γ-Fe(2)O(3) could exhibit harmful properties and therefore surface coating, cellular targeting, and local exposure should be considered before developing clinical applications. PMID:21589646

  10. Security printing of covert quick response codes using upconverting nanoparticle inks

    Science.gov (United States)

    Meruga, Jeevan M.; Cross, William M.; May, P. Stanley; Luu, QuocAnh; Crawford, Grant A.; Kellar, Jon J.

    2012-10-01

    Counterfeiting costs governments and private industries billions of dollars annually due to loss of value in currency and other printed items. This research involves using lanthanide doped β-NaYF4 nanoparticles for security printing applications. Inks comprised of Yb3+/Er3+ and Yb3+/Tm3+ doped β-NaYF4 nanoparticles with oleic acid as the capping agent in toluene and methyl benzoate with poly(methyl methacrylate) (PMMA) as the binding agent were used to print quick response (QR) codes. The QR codes were made using an AutoCAD file and printed with Optomec direct-write aerosol jetting®. The printed QR codes are invisible under ambient lighting conditions, but are readable using a near-IR laser, and were successfully scanned using a smart phone. This research demonstrates that QR codes, which have been used primarily for information sharing applications, can also be used for security purposes. Higher levels of security were achieved by printing both green and blue upconverting inks, based on combinations of Er3+/Yb3+ and Tm3+/Yb3+, respectively, in a single QR code. The near-infrared (NIR)-to-visible upconversion luminescence properties of the two-ink QR codes were analyzed, including the influence of NIR excitation power density on perceived color, in term of the CIE 1931 chromaticity index. It was also shown that this security ink can be optimized for line width, thickness and stability on different substrates.

  11. Security printing of covert quick response codes using upconverting nanoparticle inks

    International Nuclear Information System (INIS)

    Counterfeiting costs governments and private industries billions of dollars annually due to loss of value in currency and other printed items. This research involves using lanthanide doped β-NaYF4 nanoparticles for security printing applications. Inks comprised of Yb3+/Er3+ and Yb3+/Tm3+ doped β-NaYF4 nanoparticles with oleic acid as the capping agent in toluene and methyl benzoate with poly(methyl methacrylate) (PMMA) as the binding agent were used to print quick response (QR) codes. The QR codes were made using an AutoCAD file and printed with Optomec direct-write aerosol jetting®. The printed QR codes are invisible under ambient lighting conditions, but are readable using a near-IR laser, and were successfully scanned using a smart phone. This research demonstrates that QR codes, which have been used primarily for information sharing applications, can also be used for security purposes. Higher levels of security were achieved by printing both green and blue upconverting inks, based on combinations of Er3+/Yb3+ and Tm3+/Yb3+, respectively, in a single QR code. The near-infrared (NIR)-to-visible upconversion luminescence properties of the two-ink QR codes were analyzed, including the influence of NIR excitation power density on perceived color, in term of the CIE 1931 chromaticity index. It was also shown that this security ink can be optimized for line width, thickness and stability on different substrates. (paper)

  12. Photoactivation of Diiodido-Pt(IV) Complexes Coupled to Upconverting Nanoparticles.

    Science.gov (United States)

    Perfahl, Stefanie; Natile, Marta M; Mohamad, Heba S; Helm, Christiane A; Schulzke, Carola; Natile, Giovanni; Bednarski, Patrick J

    2016-07-01

    The preparation, characterization, and surface modification of upconverting lanthanide-doped hexagonal NaGdF4 nanocrystals attached to light sensitive diiodido-Pt(IV) complexes is presented. The evaluation for photoactivation and cytotoxicity of the novel carboxylated diiodido-Pt(IV) cytotoxic prodrugs by near-infrared (NIR) light (λ = 980 nm) is also reported. We attempted two different strategies for attachment of light-sensitive diiodido-Pt(IV) complexes to Yb,Er- and Yb,Tm-doped β-NaGdF4 upconverting nanoparticles (UCNPs) in order to provide nanohybrids, which offer unique opportunities for selective drug activation within the tumor cells and subsequent spatiotemporal controlled drug release by NIR-to-visible light-upconversion: (A) covalent attachment of the Pt(IV) complex via amide bond formation and (B) carboxylate exchange of oleate on the surface of the UCNPs with diiodido-Pt(IV) carboxylato complexes. Initial feasibility studies showed that NIR applied by a 980 nm laser had only a slight effect on the stability of the various diiodido-Pt(IV) complexes, but when UCNPs were present more rapid loss of the ligand-metal-charge transfer (LMCT) bands of the diiodido-Pt(IV) complexes was observed. Furthermore, Pt released from the Pt(IV) complexes platinated calf-thymus DNA (ct-DNA) more rapidly when NIR was applied compared to dark controls. Of the two attachment strategies, method A with the covalently attached diiodido-Pt(IV) carboxylates via amide bond formation proved to be the most effective method for generating UCNPs that release Pt when irradiated with NIR; the released Pt was also able to bind irreversibly to calf thymus DNA. Nonetheless, only ca. 20% of the Pt on the surface of the UCNPs was in the Pt(IV) oxidation state, the rest was Pt(II), indicating chemical reduction of the diiodido-Pt(IV) prodrug by the UCNPs. Cytotoxicity studies with the various UCNP-Pt conjugates and constructs, tested on human leukemia HL60 cells in culture, indicated a

  13. Chemical design of biocompatible iron oxide nanoparticles for medical applications.

    Science.gov (United States)

    Ling, Daishun; Hyeon, Taeghwan

    2013-05-27

    Iron oxide nanoparticles are one of the most versatile and safe nanomaterials used in medicine. Recent progress in nanochemistry enables fine control of the size, crystallinity, uniformity, and surface properties of iron oxide nanoparticles. In this review, the synthesis of chemically designed biocompatible iron oxide nanoparticles with improved quality and reduced toxicity is discussed for use in diverse biomedical applications.

  14. Transport of NaYF4:Er3+, Yb3+ up-converting nanoparticles into HeLa cells

    International Nuclear Information System (INIS)

    An effective, simple and practically useful method to incorporate fluorescent nanoparticles inside live biological cells was developed. The internalization time and concentration dependence of a frequently used liposomal transfection factor (Lipofectamine 2000) was studied. A user friendly, one-step technique to obtain water and organic solvent soluble Er3+ and Yb3+ doped NaYF4 nanoparticles coated with polyvinylpyrrolidone was obtained. Structural analysis of the nanoparticles confirmed the formation of nanocrystals of the desired sizes and spectral properties. The internalization of NaYF4 nanoparticles in HeLa cervical cancer cells was determined at different nanoparticle concentrations and for incubation periods from 3 to 24 h. The images revealed a redistribution of nanoparticles inside the cell, which increases with incubation time and concentration levels, and depends on the presence of the transfection factor. The study identifies, for the first time, factors responsible for an effective endocytosis of the up-converting nanoparticles to HeLa cells. Thus, the method could be applied to investigate a wide range of future ‘smart’ theranostic agents. Nanoparticles incorporated into the liposomes appear to be very promising fluorescent probes for imaging real-time cellular dynamics. (paper)

  15. Transport of NaYF4:Er3+, Yb3+ up-converting nanoparticles into HeLa cells

    Science.gov (United States)

    Sikora, Bożena; Fronc, Krzysztof; Kamińska, Izabela; Koper, Kamil; Szewczyk, Sebastian; Paterczyk, Bohdan; Wojciechowski, Tomasz; Sobczak, Kamil; Minikayev, Roman; Paszkowicz, Wojciech; Stępień, Piotr; Elbaum, Danek

    2013-06-01

    An effective, simple and practically useful method to incorporate fluorescent nanoparticles inside live biological cells was developed. The internalization time and concentration dependence of a frequently used liposomal transfection factor (Lipofectamine 2000) was studied. A user friendly, one-step technique to obtain water and organic solvent soluble Er3+ and Yb3+ doped NaYF4 nanoparticles coated with polyvinylpyrrolidone was obtained. Structural analysis of the nanoparticles confirmed the formation of nanocrystals of the desired sizes and spectral properties. The internalization of NaYF4 nanoparticles in HeLa cervical cancer cells was determined at different nanoparticle concentrations and for incubation periods from 3 to 24 h. The images revealed a redistribution of nanoparticles inside the cell, which increases with incubation time and concentration levels, and depends on the presence of the transfection factor. The study identifies, for the first time, factors responsible for an effective endocytosis of the up-converting nanoparticles to HeLa cells. Thus, the method could be applied to investigate a wide range of future ‘smart’ theranostic agents. Nanoparticles incorporated into the liposomes appear to be very promising fluorescent probes for imaging real-time cellular dynamics.

  16. Deep tissue optical imaging of upconverting nanoparticles enabled by exploiting higher intrinsic quantum yield through use of millisecond single pulse excitation with high peak power

    DEFF Research Database (Denmark)

    Liu, Haichun; Xu, Can T.; Dumlupinar, Gökhan;

    2013-01-01

    We have accomplished deep tissue optical imaging of upconverting nanoparticles at 800 nm, using millisecond single pulse excitation with high peak power. This is achieved by carefully choosing the pulse parameters, derived from time-resolved rate-equation analysis, which result in higher intrinsi...... therapy and remote activation of biomolecules in deep tissues....

  17. Oleyl-hyaluronan micelles loaded with upconverting nanoparticles for bio-imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pospisilova, Martina, E-mail: martina.pospisilova@contipro.com; Mrazek, Jiri; Matuska, Vit; Kettou, Sofiane; Dusikova, Monika; Svozil, Vit; Nesporova, Kristina; Huerta-Angeles, Gloria; Vagnerova, Hana; Velebny, Vladimir [Contipro Biotech (Czech Republic)

    2015-09-15

    Hyaluronan (HA) represents an interesting polymer for nanoparticle coating due to its biocompatibility and enhanced cell interaction via CD44 receptor. Here, we describe incorporation of oleate-capped β–NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+} nanoparticles (UCNP-OA) into amphiphilic HA by microemulsion method. Resulting structures have a spherical, micelle-like appearance with a hydrodynamic diameter of 180 nm. UCNP-OA-loaded HA micelles show a good stability in PBS buffer and cell culture media. The intensity of green emission of UCNP-OA-loaded HA micelles in water is about five times higher than that of ligand-free UCNP, indicating that amphiphilic HA effectively protects UCNP luminescence from quenching by water molecules. We found that UCNP-OA-loaded HA micelles in concentrations up to 50 μg mL{sup −1} increase cell viability of normal human dermal fibroblasts (NHDF), while viability of human breast adenocarcinoma cells MDA–MB–231 is reduced at these concentrations. The utility of UCNP-OA-loaded HA micelles as a bio-imaging probe was demonstrated in vitro by successful labelling of NHDF and MDA–MB–231 cells overexpressing the CD44 receptor.

  18. Upconverting nanophosphors for bioimaging

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Shuang Fang; Zhuo Rui [Department of MAE, Princeton University, Princeton, NJ 08544 (United States); Riehn, Robert [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Tung, Chih-kuan; Dalland, Joanna; Austin, Robert H [Department of Physics, Princeton University, Princeton, NJ 08544 (United States); Ryu, William S [Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544 (United States)

    2009-10-07

    Upconverting nanoparticles (UCNPs) when excited in the near-infrared (NIR) region display anti-Stokes emission whereby the emitted photon is higher in energy than the excitation energy. The material system achieves that by converting two or more infrared photons into visible photons. The use of the infrared confers benefits to bioimaging because of its deeper penetrating power in biological tissues and the lack of autofluorescence. We demonstrate here sub-10 nm, upconverting rare earth oxide UCNPs synthesized by a combustion method that can be stably suspended in water when amine modified. The amine modified UCNPs show specific surface immobilization onto patterned gold surfaces. Finally, the low toxicity of the UCNPs is verified by testing on the multi-cellular C. elegans nematode.

  19. Biocompatible and target specific hydrophobically modified glycol chitosan nanoparticles.

    Science.gov (United States)

    Yin, Wei; Li, Weiyi; Rubenstein, David A; Meng, Yizhi

    2016-01-01

    Cardiovascular disease is the leading cause of death in the United States. Atherosclerosis is a major cause for cardiovascular diseases. Drugs that treat atherosclerosis usually act nonspecifically. To enhance drug delivery specificity, the authors developed a hydrophobically modified glycol chitosan (HGC) nanoparticle that can specifically target activated endothelial cells. The biocompatibility of these nanoparticles toward red blood cells and platelets was evaluated through hemolysis, platelet activation, platelet thrombogenicity, and platelet aggregation assays. The biocompatibility of these nanoparticles toward vascular endothelial cells was evaluated by their effects on endothelial cell growth, metabolic activity, and activation. The results demonstrated that HGC nanoparticles did not cause hemolysis, or affect platelet activation, thrombogenicity, and aggregation capability in vitro. The nanoparticles did not impair vascular endothelial cell growth or metabolic activities in vitro, and did not cause cell activation either. When conjugated with intercellular adhesion molecular 1 antibodies, HGC nanoparticles showed a significantly increased targeting specificity toward activated endothelial cells. These results suggested that HGC nanoparticles are likely compatible toward red blood cells, platelets, and endothelial cells, and they can be potentially used to identify activated endothelial cells at atherosclerotic lesion areas within the vasculature, and deliver therapeutic drugs. PMID:27126597

  20. Biocompatibility of folate-modified chitosan nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Subhankari Prasad Chakraborty; Sumanta Kumar Sahu; Panchanan Pramanik; Somenath Roy

    2012-01-01

    Objective: To evaluate the acute toxicity of carboxymethyl chitosan-2, 2’ ethylenedioxy bis-ethylamine-folate (CMC-EDBE-FA) and as well as possible effect on microbial growth and in vitro cell cyto-toxicity. Methods: CMC-EDBE-FA was prepared on basis of carboxymethyl chitosan tagged with folic acid by covalently linkage through 2, 2’ ethylenedioxy bis-ethylamine. In vivo acute toxicity, in vitro cyto-toxicity and antimicrobial activity of CMC-EDBE-FA nanoparticle were determined. Results: Vancomycin exhibited the antibacterial activity against vancomycin sensitive Staphylococcus aureus, but CMC-EDBE-FA nanoparticle did not give any antibacterial activity as evidenced by minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), disc agar diffusion (DAD) and killing kinetic assay. Further, the CMC-EDBE-FA nanoparticle showed no signs of in vivo acute toxicity up to a dose level of 1000 mg/kg p.o., and as well as in vitro cyto-toxicity up to 250 μg/mL. Conclusions: These findings suggest that CMC-EDBE-FA nanoparticle is expected to be safe for biomedical applications.

  1. Up-converting NaYF4:0.1%Tm3+, 20%Yb3+nanoparticles as luminescent labels for deep-tissue optical imaging

    Institute of Scientific and Technical Information of China (English)

    A. Gnach; K. Prorok; M. Misiak; B. Cichy; A. Bednarkiewicz

    2014-01-01

    Optical imaging plays an important role in biomedical research being extremely useful for early detection, screening and image-guided therapy. Lanthanide-doped up-converting nanoparticles were ideally suited for bioimaging because they could be ex-cited in near infrared (NIR) and emit in NIR or visible (VIS). Here, we compared lanthanide doped up-converting NaYF4 and organic fluorophores for application in deep-tissue imaging. For that purpose-tissue phantoms mimicking the natural properties of light scat-tering by living tissues were prepared. The studies allowed to quantitatively compare optical resolution of different fluorescent com-pounds, revealing that the NIR photoexcitation was favorable over conventional UV photoexcitation.

  2. Widefield imaging of upconverting nanoparticles on epifluorescence microscopes adapted for laser illumination with top-hat profile

    Science.gov (United States)

    Mrazek, Jiri; Pospisilova, Martina; Svozil, Vit; Cadek, Ondrej; Nesporova, Kristina; Sulakova, Romana; Brandejsova, Martina; Vranova, Jana; Velebny, Vladimir

    2016-05-01

    We describe a modification of epifluorescence microscopes that allows quantitative widefield imaging of samples labeled by upconverting nanoparticles (UCNP). A top-hat illumination profile on the sample was achieved with a 980-nm laser diode by using tandem microlens arrays, a moving diffuser and a telescope, which adjusts the top-hat area to the field of view. Illumination homogeneity is a critical factor for imaging of UCNP since the intensity of their luminescence typically scales with the second power of the excitation intensity. Our illuminator is combined with the epifluorescence attachment of the microscope, allowing easy switching between observation of UCNP and traditional fluorescent dyes. Illumination profile homogeneity of about 98% was measured for objectives with magnification from 4× to 100×, and the top-hat profile was also obtained with phase contrast objectives. We demonstrate capability of the illuminator by evaluating in vitro uptake of UCNP encapsulated in oleyl-hyaluronan micelles into breast cancer cells. Micelles bearing the targeting peptide were about an order of magnitude more efficient than nontargeted micelles.

  3. Clear-cut observation of clearance of sustainable upconverting nanoparticles from lymphatic system of small living mice

    Science.gov (United States)

    Park, Hye Sun; Nam, Sang Hwan; Kim, Jongwoo; Shin, Hyung Seon; Suh, Yung Doug; Hong, Kwan Soo

    2016-06-01

    The significance of lymphatic system has gathered great attention for immunotechnology related to cancer metastasis and immunotherapy. To develop innovative immunodiagnostics and immunotherapy in in vivo environments, it is very important to understand excretion pathways and clearance of injected cargoes. Herein, we employed Tm3+-doped upconverting nanoparticles (UCNPs) with versatile advantages suitable for long-term non-invasive in vivo optical imaging and tracking. Transport and retention of the UCNPs in the lymphatic system were evaluated with high-quality NIR-to-NIR upconversion luminescence (UCL) imaging. We obtained their kinetic luminescence profiles for the injection site and sentinel lymph node (SLN) and observed luminescence signals for one month; we also examined UCL images in SLN tissues, organs, and faeces at each time point. We speculate that the injected UCNPs in a footpad of a small mouse are transported rapidly from the lymphatic system to the blood system and then eventually result in an efficient excretion by the hepatobiliary route. These results will support development of novel techniques for SLN biopsy as well as immunotechnology.

  4. Dissolution Mechanism of Upconverting AYF4:Yb,Tm (A = Na or K) Nanoparticles in Aqueous Media.

    Science.gov (United States)

    Lisjak, Darja; Plohl, Olivija; Vidmar, Janja; Majaron, Boris; Ponikvar-Svet, Maja

    2016-08-16

    The dissolution of upconverting AYF4:Yb,Tm (A = Na or K) nanoparticles (UCNPs) in aqueous media was systematically studied. UCNPs with a cubic structure and sizes of between 10 and 33 nm were synthesized solvothermally in ethylene glycol at 200 °C. The UCNPs of both compositions showed an upconversion fluorescence emission characteristic of Tm(3+). The effects of the A cation, the particle size, the temperature, the pH, and the composition of the aqueous medium on the dissolution of the UCNPs were evaluated. The degree of dissolution was determined from the fraction of dissolved fluoride (F(-)) using potentiometry. Unexpectedly, the composition of aqueous media had the most significant effect on the dissolution of the UCNPs. The highest degree of dissolution and rate were measured for the phosphate-buffered saline (PBS), which can be explained by the formation of stable lanthanide compounds with phosphates. The degree of dissolution was much lower in water and in the phthalate buffer, which was attributed to the release of F(-) as a result of the hydrolysis of the UCNPs' surfaces. PMID:27459496

  5. Methods and apparatus for transparent display using up-converting nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Chia Wei; Qiu, Wenjun; Zhen, Bo; Shapira, Ofer; Soljacic, Marin

    2016-10-04

    Disclosed herein are transparent color displays with nanoparticles made with nonlinear materials and/or designed to exhibit optical resonances. These nanoparticles are embedded in or hosted on a transparent substrate, such as a flexible piece of clear plastic or acrylic. Illuminating the nanoparticles with invisible light (e.g., infrared or ultraviolet light) causes them to emit visible light. For example, a rare-earth doped nanoparticle may emit visible light when illuminated simultaneoulsy with a first infrared beam at a first wavelength .lamda..sub.1 and a second infrared beam at a second wavelength .lamda..sub.2. And a frequency-doubling nanoparticle may emit visible light when illuminated with a single infrared beam at the nanoparticle's resonant frequency. Selectively addressing these nanoparticles with appropiately selected pump beams yields visible light emitted from the nanoparticles hosted by the transparent substrate in a desired pattern.

  6. Methods and apparatus for transparent display using up-converting nanoparticles

    Science.gov (United States)

    Hsu, Chia Wei; Qiu, Wenjun; Zhen, Bo; Shapira, Ofer; Soljacic, Marin

    2016-10-04

    Disclosed herein are transparent color displays with nanoparticles made with nonlinear materials and/or designed to exhibit optical resonances. These nanoparticles are embedded in or hosted on a transparent substrate, such as a flexible piece of clear plastic or acrylic. Illuminating the nanoparticles with invisible light (e.g., infrared or ultraviolet light) causes them to emit visible light. For example, a rare-earth doped nanoparticle may emit visible light when illuminated simultaneoulsy with a first infrared beam at a first wavelength .lamda..sub.1 and a second infrared beam at a second wavelength .lamda..sub.2. And a frequency-doubling nanoparticle may emit visible light when illuminated with a single infrared beam at the nanoparticle's resonant frequency. Selectively addressing these nanoparticles with appropiately selected pump beams yields visible light emitted from the nanoparticles hosted by the transparent substrate in a desired pattern.

  7. A green chemistry approach for synthesizing biocompatible gold nanoparticles

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, JaeWoong; Park, Jung Hyun; Kim, Jin-Hoi

    2014-05-01

    Gold nanoparticles (AuNPs) are a fascinating class of nanomaterial that can be used for a wide range of biomedical applications, including bio-imaging, lateral flow assays, environmental detection and purification, data storage, drug delivery, biomarkers, catalysis, chemical sensors, and DNA detection. Biological synthesis of nanoparticles appears to be simple, cost-effective, non-toxic, and easy to use for controlling size, shape, and stability, which is unlike the chemically synthesized nanoparticles. The aim of this study was to synthesize homogeneous AuNPs using pharmaceutically important Ganoderma spp . We developed a simple, non-toxic, and green method for water-soluble AuNP synthesis by treating gold (III) chloride trihydrate (HAuCl4) with a hot aqueous extract of the Ganoderma spp . mycelia. The formation of biologically synthesized AuNPs (bio-AuNPs) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the biocompatibility of as-prepared AuNPs was evaluated using a series of assays, such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation (ROS) in human breast cancer cells (MDA-MB-231). The color change of the solution from yellow to reddish pink and strong surface plasmon resonance were observed at 520 nm using UV-visible spectroscopy, and that indicated the formation of AuNPs. DLS analysis revealed the size distribution of AuNPs in liquid solution, and the average size of AuNPs was 20 nm. The size and morphology of AuNPs were investigated using TEM. The biocompatibility effect of as-prepared AuNPs was investigated in MDA-MB-231 breast cancer cells by using various concentrations of AuNPs (10 to 100 μM) for 24 h. Our findings suggest that AuNPs are non-cytotoxic and biocompatible. To the best of our knowledge

  8. In Vitro Biocompatibility of Endodontic Sealers Incorporating Antibacterial Nanoparticles

    Directory of Open Access Journals (Sweden)

    Itzhak Abramovitz

    2012-01-01

    Full Text Available The main cause of endodontic disease is bacteria. Disinfection is presently achieved by cleaning the root canal system prior to obturation. Following setting, root canal filling is devoid of any antibacterial effect. Endodontic sealers with antimicrobial properties yet biocompatible may enhance root canal therapy. For this purpose, quaternized polyethylenimine nanoparticles which are antibacterial polymers, biocompatible, nonvolatile, and stable may be used. The aim of the present study was to examine the impact of added QPEI on the cytotoxicity of AH Plus, Epiphany, and GuttaFlow endodontic sealers. The effect of these sealers on the proliferation of RAW 264.7 macrophage and L-929 fibroblast cell lines and on the production of TNFα from macrophages was examined. Cell vitality was evaluated using a colorimetric XTT assay. The presence of cytokines was determined by two-site ELISA. Results show that QPEI at 1% concentration does not impair the basic properties of the examined sealers in both macrophages and fibroblast cell lines. Incorporation of 1% QPEI into the sealers did not impair their biocompatibility. QPEI is a potential clinical candidate to improve antibacterial activity of sealers without increasing cytotoxicity.

  9. Biocompatible fluorescent nanoparticles for in vivo stem cell tracking

    Science.gov (United States)

    Cova, Lidia; Bigini, Paolo; Diana, Valentina; Sitia, Leopoldo; Ferrari, Raffaele; Pesce, Ruggiero Maria; Khalaf, Rushd; Bossolasco, Patrizia; Ubezio, Paolo; Lupi, Monica; Tortarolo, Massimo; Colombo, Laura; Giardino, Daniela; Silani, Vincenzo; Morbidelli, Massimo; Salmona, Mario; Moscatelli, Davide

    2013-06-01

    Efficient application of stem cells to the treatment of neurodegenerative diseases requires safe cell tracking to follow stem cell fate over time in the host environment after transplantation. In this work, for the first time, fluorescent and biocompatible methyl methacrylate (MMA)-based nanoparticles (fluoNPs) were synthesized through a free-radical co-polymerization process with a fluorescent macromonomer obtained by linking Rhodamine B and hydroxyethyl methacrylate. We demonstrate that the fluoNPs produced by polymerization of MMA-Rhodamine complexes (1) were efficient for the labeling and tracking of multipotent human amniotic fluid cells (hAFCs); (2) did not alter the main biological features of hAFCs (such as viability, cell growth and metabolic activity); (3) enabled us to determine the longitudinal bio-distribution of hAFCs in different brain areas after graft in the brain ventricles of healthy mice by a direct fluorescence-based technique. The reliability of our approach was furthermore confirmed by magnetic resonance imaging analyses, carried out by incubating hAFCs with both superparamagnetic iron oxide nanoparticles and fluoNPs. Our data suggest that these finely tunable and biocompatible fluoNPs can be exploited for the longitudinal tracking of stem cells.

  10. Biocompatible fluorescent nanoparticles for in vivo stem cell tracking

    International Nuclear Information System (INIS)

    Efficient application of stem cells to the treatment of neurodegenerative diseases requires safe cell tracking to follow stem cell fate over time in the host environment after transplantation. In this work, for the first time, fluorescent and biocompatible methyl methacrylate (MMA)-based nanoparticles (fluoNPs) were synthesized through a free-radical co-polymerization process with a fluorescent macromonomer obtained by linking Rhodamine B and hydroxyethyl methacrylate. We demonstrate that the fluoNPs produced by polymerization of MMA–Rhodamine complexes (1) were efficient for the labeling and tracking of multipotent human amniotic fluid cells (hAFCs); (2) did not alter the main biological features of hAFCs (such as viability, cell growth and metabolic activity); (3) enabled us to determine the longitudinal bio-distribution of hAFCs in different brain areas after graft in the brain ventricles of healthy mice by a direct fluorescence-based technique. The reliability of our approach was furthermore confirmed by magnetic resonance imaging analyses, carried out by incubating hAFCs with both superparamagnetic iron oxide nanoparticles and fluoNPs. Our data suggest that these finely tunable and biocompatible fluoNPs can be exploited for the longitudinal tracking of stem cells. (paper)

  11. Polyaniline-coated upconversion nanoparticles with upconverting luminescent and photothermal conversion properties for photothermal cancer therapy.

    Science.gov (United States)

    Xing, Yadong; Li, Luoyuan; Ai, Xicheng; Fu, Limin

    2016-01-01

    In this study, we developed a nanosystem based on upconversion nanoparticles (UCNPs) coated with a layer of polyaniline nanoparticles (PANPs). The UCNP induces upconversion luminescence for imaging and photothermal conversion properties are due to PANPs. In vitro experiments showed that the UCNPs-PANPs were nontoxic to cells even at a high concentration (800 µg mL(-1)). Blood analysis and histological experiments demonstrated that the UCNPs-PANPs exhibited no apparent toxicity in mice in vivo. Besides their efficacy in photothermal cancer cell ablation, the UCNP-PANP nanosystem was found to achieve an effective in vivo tumor ablation effect after irradiation using an 808 nm laser. These results demonstrate the potential of the hybrid nanocomposites for use in imaging-guided photothermal therapy. PMID:27621625

  12. Polyaniline-coated upconversion nanoparticles with upconverting luminescent and photothermal conversion properties for photothermal cancer therapy

    Directory of Open Access Journals (Sweden)

    Xing YD

    2016-09-01

    Full Text Available Yadong Xing, Luoyuan Li, Xicheng Ai, Limin Fu Department of Chemistry, Renmin University of China, Beijing, People’s Republic of China Abstract: In this study, we developed a nanosystem based on upconversion nanoparticles (UCNPs coated with a layer of polyaniline nanoparticles (PANPs. The UCNP induces upconversion luminescence for imaging and photothermal conversion properties are due to PANPs. In vitro experiments showed that the UCNPs-PANPs were nontoxic to cells even at a high concentration (800 µg mL-1. Blood analysis and histological experiments demonstrated that the UCNPs-PANPs exhibited no apparent toxicity in mice in vivo. Besides their efficacy in photothermal cancer cell ablation, the UCNP-PANP nanosystem was found to achieve an effective in vivo tumor ablation effect after irradiation using an 808 nm laser. These results demonstrate the potential of the hybrid nanocomposites for use in imaging-guided photothermal therapy. Keywords: upconversion nanoparticles, polyaniline, upconversion luminescence, photothermal therapy

  13. Synthesis of biocompatible nanoparticle drug complexes for inhibition of mycobacteria

    Science.gov (United States)

    Bhave, Tejashree; Ghoderao, Prachi; Sanghavi, Sonali; Babrekar, Harshada; Bhoraskar, S. V.; Ganesan, V.; Kulkarni, Anjali

    2013-12-01

    Tuberculosis (TB) is one of the most critical infectious diseases affecting the world today. Current TB treatment involves six months long daily administration of four oral doses of antibiotics. Due to severe side effects and the long treatment, a patient's adherence is low and this results in relapse of symptoms causing an alarming increase in the prevalence of multi-drug resistant (MDR) TB. Hence, it is imperative to develop a new drug delivery technology wherein these effects can be reduced. Rifampicin (RIF) is one of the widely used anti-tubercular drugs (ATD). The present study discusses the development of biocompatible nanoparticle-RIF complexes with superior inhibitory activity against both Mycobacterium smegmatis (M. smegmatis) and Mycobacterium tuberculosis (M. tuberculosis). Iron oxide nanoparticles (NPs) synthesized by gas phase condensation and NP-RIF complexes were tested against M. smegmatis SN2 strain as well as M. tuberculosis H37Rv laboratory strain. These complexes showed significantly better inhibition of M. smegmatis SN2 strain at a much lower effective concentration (27.5 μg ml-1) as compared to neat RIF (125 μg ml-1). Similarly M. tuberculosis H37Rv laboratory strain was susceptible to both nanoparticle-RIF complex and neat RIF at a minimum inhibitory concentration of 0.22 and 1 μg ml-1, respectively. Further studies are underway to determine the efficacy of NPs-RIF complexes in clinical isolates of M. tuberculosis as well as MDR isolates.

  14. Biocompatible hydrodispersible magnetite nanoparticles used as antibiotic drug carriers.

    Science.gov (United States)

    Bolocan, Alexandra; Mihaiescu, Dan Eduard; Andronescu, Ecaterina; Voicu, Georgeta; Grumezescu, Alexandru Mihai; Ficai, Anton; Vasile, Bogdan Ştefan; Bleotu, Coralia; Chifiriuc, Mariana Carmen; Pop, Corina Silvia

    2015-01-01

    Here we report a newly synthesized vectorizing nanosystem, based on hydrodispersible magnetite nanoparticles (HMNPs) with an average size less than 10 nm, obtained by precipitation of Fe(II) and Fe(III) in basic solution of p-aminobenzoic acid (PABA), characterized by high-resolution transmission electron microscopy (HR-TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), differential thermal analysis coupled with thermogravimetric analysis (DTA-TGA) and bioevaluated for cytotoxicity and antibiotic delivery in active forms. The obtained data demonstrate that HMNPs can be used as an efficient drug delivery system, for clinically relevant antimicrobial drugs. HMNPs antimicrobial activity depended on the loaded drug structure and the tested microbial strain, being more efficient against Pseudomonas aeruginosa, comparing with the Escherichia coli strain. The novel HMNPs demonstrated an acceptable biocompatibility level, being thus a very good candidate for biomedical applications, such as drug delivery or targeting.

  15. Far-field optical nanothermometry using individual sub-50 nm upconverting nanoparticles

    Science.gov (United States)

    Kilbane, Jacob D.; Chan, Emory M.; Monachon, Christian; Borys, Nicholas J.; Levy, Elizabeth S.; Pickel, Andrea D.; Urban, Jeffrey J.; Schuck, P. James; Dames, Chris

    2016-06-01

    We demonstrate far-field optical thermometry using individual NaYF4 nanoparticles doped with 2% Er3+ and 20% Yb3+. Isolated 20 × 20 × 40 nm3 particles were identified using only far-field optical imaging, confirmed by subsequent scanning electron microscopy. The luminescence thermometry response for five such single particles was characterized for temperatures from 300 K to 400 K. A standard Arrhenius model widely used for larger particles can still be accurately applied to these sub-50 nm particles, with good particle-to-particle uniformity (response coefficients exhibited standard deviations below 5%). With its spatial resolution on the order of 50 nm when imaging a single particle, far below the diffraction limit, this technique has potential applications for both fundamental thermal measurements and nanoscale metrology in industrial applications.We demonstrate far-field optical thermometry using individual NaYF4 nanoparticles doped with 2% Er3+ and 20% Yb3+. Isolated 20 × 20 × 40 nm3 particles were identified using only far-field optical imaging, confirmed by subsequent scanning electron microscopy. The luminescence thermometry response for five such single particles was characterized for temperatures from 300 K to 400 K. A standard Arrhenius model widely used for larger particles can still be accurately applied to these sub-50 nm particles, with good particle-to-particle uniformity (response coefficients exhibited standard deviations below 5%). With its spatial resolution on the order of 50 nm when imaging a single particle, far below the diffraction limit, this technique has potential applications for both fundamental thermal measurements and nanoscale metrology in industrial applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01479h

  16. Polymeric nanocapsules with up-converting nanocrystals cargo make ideal fluorescent bioprobes

    Science.gov (United States)

    Bazylińska, U.; Wawrzyńczyk, D.; Kulbacka, J.; Frąckowiak, R.; Cichy, B.; Bednarkiewicz, A.; Samoć, M.; Wilk, K. A.

    2016-07-01

    An innovative approach for up-converting nanoparticles adaptation for bio-related and theranostic applications is presented. We have successfully encapsulated multiple, ~8 nm in size NaYF4 nanoparticles inside the polymeric nanocarriers with average size of ~150 nm. The initial coating of nanoparticles surfaces was preserved due to the hydrophobic environment inside the nanocapsules, and thus no single nanoparticle surface functionalization was necessary. The selection of biodegradable and sugar-based polyelectrolyte shells ensured biocompatibility of the nanostructures, while the choice of Tm3+ and Yb3+ NaYF4 nanoparticles co-doping allowed for near-infrared to near-infrared bioimaging of healthy and cancerous cell lines. The protective role of organic shell resulted in not only preserved high up-converted emission intensity and long luminescence lifetimes, without quenching from water environment, but also ensured low cytotoxicity and high cellular uptake of the engineered nanocapsules. The multifunctionality of the proposed nanocarriers is a consequence of both the organic exterior part that is accessible for conjugation with biologically important molecules, and the hydrophobic interior, which in future application may be used as a container for co-encapsulation of inorganic nanoparticles and anticancer drug cargo.

  17. Unraveling Triplet Excitons Photophysics in Hyper-Cross-Linked Polymeric Nanoparticles: Toward the Next Generation of Solid-State Upconverting Materials.

    Science.gov (United States)

    Monguzzi, Angelo; Mauri, Michele; Frigoli, Michel; Pedrini, Jacopo; Simonutti, Roberto; Larpent, Chantal; Vaccaro, Gianfranco; Sassi, Mauro; Meinardi, Francesco

    2016-07-21

    The technological application of sensitized upconversion based on triplet-triplet annihilation (TTA) requires the transition from systems operating in liquid solutions to solid-state materials. Here, we demonstrate that the high upconversion efficiency reported in hyper-cross-linked nanoparticles does not originate from residual mobility of the embedded dyes as it happens in soft hosts. The hyper-reticulation from one side blocks the dyes in fixed positions, but on the other one, it suppresses the nonradiative spontaneous decay of the triplet excitons, reducing intramolecular relaxations. TTA is thus enabled by an unprecedented extension of the triplet lifetime, which grants long excitons diffusion lengths by hopping among the dye framework and gives rise to high upconversion yield without any molecular displacement. This finding paves the way for the design of a new class of upconverting materials, which in principle can operate at excitation intensities even lower than those requested in liquid or in rubber hosts. PMID:27388582

  18. Biocompatibility and Toxicity of Magnetic Nanoparticles in Regenerative Medicine

    Directory of Open Access Journals (Sweden)

    H. Markides

    2012-01-01

    Full Text Available Regenerative medicine is a pioneering field aimed at restoring and regenerating the function of damaged cells, organs and tissues in order to establish normal function. It demands the cross communication of disciplines to develop effective therapeutic stem cell based therapies. Nanotechnology has been instrumental in the development and translation of basic research to the clinically relevant therapies. In particular, magnetic nanoparticles (MNPs have been applied to tag, track and activate stem cells offering an effective means of monitoring in vitro and in vivo behaviour. MNPs are comprised of an iron oxide core with a biocompatible biological polymer. Safety is an issue of constant concern and emphasises on the importance of investigating the issue of toxicity. Any indication of toxicity can ultimately limit the therapeutic efficiency of the therapy. Toxicity is highly dependent on the physical, chemical and structural properties of the MNP itself as well as dose and intended use. Few in vitro studies have reported adverse effects of MNP on cells at in vitro in therapeutic doses. However, long term in vivo studies have not been studied as extensively. This review aims to summarise current research in this topic highlighting commonly used toxicity assays to investigate this.

  19. Biocompatibility of various ferrite nanoparticles evaluated by in vitro cytotoxicity assays using HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Tomitaka, Asahi [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan)], E-mail: d07gd158@ynu.ac.jp; Hirukawa, Atsuo; Yamada, Tsutomu [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan); Morishita, Shin [Department of Mechanical Engineering and Materials Science, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan); Takemura, Yasushi [Department of Electrical and Computer Engineering, Yokohama National University, Tokiwadai 79-5, Yokohama, Kanagawa 240-8501 (Japan)

    2009-05-15

    Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Fe{sub 3}O{sub 4} (20-30 nm), ZnFe{sub 2}O{sub 4} (15-30 nm) and NiFe{sub 2}O{sub 4} (20-30 nm) nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. The Fe{sub 3}O{sub 4} sample was found to be biocompatible on HeLa cells. While ZnFe{sub 2}O{sub 4} and NiFe{sub 2}O{sub 4} were non-toxic at low concentrations, HeLa cells exhibited cytotoxic effects when exposed to concentrations of 100 {mu}g/ml nanoparticles.

  20. Aptamer-based luminescence energy transfer from near-infrared-to-near-infrared upconverting nanoparticles to gold nanorods and its application for the detection of thrombin.

    Science.gov (United States)

    Yuan, Fei; Chen, Hongqi; Xu, Juan; Zhang, Yiyan; Wu, Yong; Wang, Lun

    2014-03-01

    A new luminescence energy transfer (LET) system has been designed for the detection of thrombin in the near-infrared (NIR) region by utilizing NIR-to-NIR upconversion lanthanide nanophosphors (UCNPs) as the donor and gold nanorods (Au NRs) as the acceptor. The use of upconverting NaYF4 :Yb(3+) ,Tm(3+) nanoparticles with sharp NIR emission peaks upon NIR excitation by an inexpensive infrared continuous wave laser diode provided large spectral overlap between the donor and the acceptor. Both the Au NRs and carboxyl-terminated NaYF4 :Yb(3+) ,Tm(3+) UCNPs were first modified with different thrombin aptamers. When thrombin was added, a LET system was then formed because of the specific recognition between the thrombin aptamers and thrombin. The LET system was used to monitor thrombin concentrations in aqueous buffer and human blood samples. The limits of detection for thrombin are as low as 0.118 nM in buffer solution and 0.129 nM in human serum. The method was also successfully applied to thrombin detection in blood samples. PMID:24501010

  1. Preparation and Characterization of Nateglinide Loaded Hydrophobic Biocompatible Polymer Nanoparticles

    Science.gov (United States)

    Naik, Jitendra; Lokhande, Amolkumar; Mishra, Satyendra; Kulkarni, Ravindra

    2016-09-01

    The aim of the present study was to develop sustained release Nateglinide loaded Ethylcellulose nanoparticles and characterize the properties of recovered nanoparticles. The sustained release nanoparticles were prepared by oil in water single emulsion solvent evaporation method. The developed nanoparticles were characterised for their particle size, morphology, encapsulation efficiency, drug polymer compatibility and in vitro drug release. The drug polymer compatibility was investigated by XRPD. Imaging of particles was performed by field emission scanning electron microscopy. The highest particle size and encapsulation efficiency of recovered nanoparticles were 248.37 nm and 91.16 % respectively. The recovered nanoparticles are spherical in nature and uniform in size. Developed nanoparticles have low crystallinity than the pure Nateglinide. The highest drug-polymer ratio formulation showed drug release 61.1 ± 1.76 % up to 24 h.

  2. Evaluation of biocompatible stabilised gelled soya bean oil nanoparticles as new hydrophobic reservoirs.

    Science.gov (United States)

    Boudier, Ariane; Kirilov, Plamen; Franceschi-Messant, Sophie; Belkhelfa, Haouaria; Hadioui, Laila; Roques, Christine; Perez, Emile; Rico-Lattes, Isabelle

    2010-01-01

    Based on the organogel concept, in which an oil is trapped in a network of low-molecular-mass organic gelator fibres creating a gel, a formulation of gelled soya bean oil nanoparticles was evaluated for its capacity to form biocompatible hydrophobic reservoirs. The aqueous dispersions of nanoparticles were prepared by hot emulsification (T° > Tgel) and cooling at room temperature in the presence of polyethyleneimine (PEI). The dispersions were stabilised by the electrostatic interactions between the positively charged amino groups of the PEI and the negatively charged carboxylates of the gelator fibres present at the surface of the particles. The aqueous dispersions were highly stable (several months) and the gelled particles were able to entrap a hydrophobic fluorescent model molecule (Nile red), allowing testing in cells. The gelled oil nanoparticles were found to be biocompatible with the tested cells (keratinocytes) and had the ability to become rapidly internalised. Thus, organogel-based nanoparticles are a promising hydrophobic drug delivery system.

  3. Turn-on detection of a cancer marker based on near-infrared luminescence energy transfer from NaYF4:Yb,Tm/NaGdF4 core-shell upconverting nanoparticles to gold nanorods.

    Science.gov (United States)

    Chen, Hongqi; Guan, Yingying; Wang, Shaozhen; Ji, Yuan; Gong, Mengqi; Wang, Lun

    2014-11-01

    A homogeneous immunoassay for the sensitive and selective determination of trace amounts of α-fetoprotein (AFP, a cancer marker) by detection in the near-infrared (NIR) region based on luminescence energy transfer (LET) from NaYF4:Yb,Tm/NaGdF4 core-shell upconverting nanoparticles to gold nanorods (GNRs) is presented. The carboxyl-functionalized NaYF4:Yb,Tm/NaGdF4 core-shell upconverting nanoparticles (UCNPs) were excited by a 980 nm continuous wavelength laser, and its emission peak appeared at a near-infrared wavelength (∼804 nm). The carboxyl-functionalized upconverting nanoparticles were conjugated with the anti-AFP (Ab1) and acted as donor. GNRs with a high absorption band around 790 nm, which was overlapped the UCNPs emission, were synthesized and acted as the acceptor. The donor (negatively charged) interacted with the acceptor (positively charged) via electrostatic interactions to bring them into close proximity. LET could occur, producing a quenching phenomenon. When the AFP antigens were added into the system, the binding affinity between AFP and Ab1 was stronger than the electrostatic interactions, which released the energy acceptors from the energy donors, interrupting luminescence energy transfer, and therefore, the luminescence was recovered. On the basis of the restored luminescence, a turn-on optical immunosening system was developed. Under the optimal conditions, the linear range of detection was from 0.18 to 11.44 ng/mL for AFP (R = 0.99), with a detection limit as low as 0.16 ng/mL. The proposed method has also been used to monitor AFP in human serum samples. Therefore, further study based on the NaYF4:Yb,Tm/NaGdF4 core-shell nanoparticles-GNRs construction may open the way for a new class of NIR-LET biosensors with wide applications. PMID:25296290

  4. Preparation of Biocompatible Carboxymethyl Chitosan Nanoparticles for Delivery of Antibiotic Drug

    OpenAIRE

    Liang Zhao; Bingya Zhu; Yunhong Jia; Wenjiu Hou; Chang Su

    2013-01-01

    Objective. To prepare biocompatible ciprofloxacin-loaded carboxymethyl chitosan nanoparticles (CCC NPs) and evaluate their cell specificity as well as antibacterial activity against Escherichia coli in vitro. Methods. CCC NPs were prepared by ionic cross-linking method and optimized by using Box-Behnken response surface method (BBRSM). Zeta potential, drug encapsulation, and release of the obtained nanoparticles in vitro were thoroughly investigated. Minimum inhibitory concentration (MIC) and...

  5. Silica encapsulation of luminescent silicon nanoparticles: stable and biocompatible nanohybrids

    Energy Technology Data Exchange (ETDEWEB)

    Maurice, Vincent [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France); Rivolta, Ilaria [University of Milano-Bicocca, Department of Experimental Medicine (DIMS) (Italy); Vincent, Julien [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France); Raccurt, Olivier [CEA Grenoble, Department of Nano Materials, NanoChemistry and NanoSafety Laboratory (DRT/LITEN/DTNM/LCSN) (France); Rouzaud, Jean-Noel [Ecole Normale superieure de Paris, Laboratoire de Geologie (France); Miserrochi, Giuseppe [University of Milano-Bicocca, Department of Experimental Medicine (DIMS) (Italy); Doris, Eric [CEA, Service de Chimie Bioorganique et de Marquage, iBiTecS (France); Reynaud, Cecile; Herlin-Boime, Nathalie, E-mail: nathalie.herlin@cea.fr [CEA Saclay, DSM/IRAMIS/SPAM-LFP (France)

    2012-02-15

    This article presents a process for surface coating and functionalization of luminescent silicon nanoparticles. The particles were coated with silica using a microemulsion process that was adapted to the fragile silicon nanoparticles. The as-produced core-shell particles have a mean diameter of 35 nm and exhibit the intrinsic photoluminescence of the silicon core. The silica layer protects the core from aqueous oxidation for several days, thus allowing the use of the nanoparticles for biological applications. The nanoparticles were further coated with amines and functionalized with polyethylene glycol chains and the toxicity of the particles has been evaluated at the different stages of the process. The core-shell nanoparticles exhibit no acute toxicity towards lung cells, which is promising for further development.

  6. Biocompatibility study of protein capped and uncapped silver nanoparticles on human hemoglobin

    International Nuclear Information System (INIS)

    The interactions of human hemoglobin with protein capped silver nanoparticles and bare silver nanoparticles were studied to understand fundamental perspectives about the biocompatibility of protein capped silver nanoparticles compared with bare silver nanoparticles. Bare silver (Ag) nanoparticles (NPs) were prepared by the chemical reduction method. High resolution transmission electron microscopy (HRTEM) analysis along with absorption at ∼390 nm indicated the formation of bare Ag NPs. Protein coated Ag NPs were prepared by a green synthesis method. Absorption at ∼440 nm along with ∼280 nm indicated the formation of protein coated Ag NPs. The biocompatibility of the above mentioned Ag NPs was studied by interaction with human hemoglobin (Hb) protein. In presence of bare Ag NPs, the Soret band of Hb was red shifted. This revealed the distortion of iron from the heme pockets of Hb. Also, the fluorescence peak of Hb was quenched and red shifted which indicated that Hb became unfolded in the presence of bare Ag NPs. No red shift of the absorption of Soret, along with no shift and quenching of the fluorescence peak of Hb were observed in the presence of protein coated Ag NPs. A hemolysis assay suggested that protein coated Ag NPs were more biocompatible than bare one. (paper)

  7. Preparation and properties of bio-compatible magnetic Fe3O4 nanoparticles

    International Nuclear Information System (INIS)

    In this work, we study the preparation and properties of bio-compatible magnetic nanoparticles for immunoassay and DNA detection. The magnetite (Fe3O4) nanoparticles were prepared by a chemical co-precipitation method and dextran was selected as the surfactant to suspend the nanoparticles. Suspended particles associated with avidin followed by biotin were qualitatively analyzed by enzyme-linked immunosorbent assay (ELISA) method. We found further the ethylenediamine blocked activated residual groups efficiently, hence enhancing the attachment of biotin for probing the avidin

  8. Ultrasonic investigation of magnetic nanoparticles suspension with PEG biocompatible coating

    International Nuclear Information System (INIS)

    Water suspension of nanoparticles was studied by ultrasound spectroscopy. Nanoparticles have a core-shell structure with magnetic core Fe3O4 and surfactant shells. The surface of magnetic particles was coated with oleate sodium as the primary layer and polyethylene glycol as the secondary layer. The acoustic properties of suspensions, such as velocity and attenuation of ultrasonic waves, have been measured. From experimental data mechanical properties have been determined. Adiabatic compressibility of nanoparticles suspension decreased with increase of temperature. The changes of ultrasonic wave attenuation under the influence of the external magnetic field, show that magnetic liquids with high concentration of magnetic material (despite two surfactant shells) show tendency to aggregate. - Research highlights: → Elastic properties of magnetic nanoparticles water suspension. → Molecular weight of the poly(ethylene glycol)s has effect on the ultrasound velocity and adiabatic compressibility. → Magnetic fluids with high concentrations of magnetic material, in spite of two surfactant shells show tendency to aggregate.

  9. Characterization and Biocompatibility of Chitosan Gels with Silver and Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    C. Sámano-Valencia

    2014-01-01

    Full Text Available The presence of bacterial resistance to antibiotics is a very important issue and the search of new alternatives is necessary. In this work, a combination of chitosan gel with silver or gold nanoparticles was prepared and characterized using thermal, rheology, bactericide, and biocompatibility analyses. ESEM images were also taken to visualize the incorporation of the nanoparticles into the gel matrix. Thermal analysis showed a better thermal stability in the chitosan-gold nanoparticles gels compared to the chitosan-silver nanoparticles gels. Rheology analyses showed that the viscosity of the gels decreased when velocity increased and there were differences in viscosity when silver and gold nanoparticles concentrations change. ESEM images showed the presence of agglomerates of silver and gold nanoparticles into the gel matrix with a good distribution; in some cases the formation of microstructures was found. Bactericide results show that these materials present an antibacterial activity against S. aureus, S. mutans, and E. coli. The biocompatibility test showed neither negative reaction nor wound healing delay after the application of the gels in an in vivo test. The gels with silver and gold nanoparticles could be used to treat wound infections in oral or skin applications.

  10. Real-time, non-invasive monitoring of hydrogel degradation using LiYF4:Yb(3+)/Tm(3+) NIR-to-NIR upconverting nanoparticles.

    Science.gov (United States)

    Jalani, Ghulam; Naccache, Rafik; Rosenzweig, Derek H; Lerouge, Sophie; Haglund, Lisbet; Vetrone, Fiorenzo; Cerruti, Marta

    2015-07-14

    To design a biodegradable hydrogel as cell support, one should know its in vivo degradation rate. A technique commonly used to track gel degradation is fluorescence spectroscopy. However, the fluorescence from conventional fluorophores quickly decays, and the fluorophores are often moderately cytotoxic. Most importantly, they require ultraviolet or visible (UV-Vis) light as the excitation source, which cannot penetrate deeply through biological tissues. Lanthanide-doped upconverting nanoparticles (UCNPs) are exciting alternatives to conventional fluorophores because they can convert near-infrared (NIR) to UV-Vis-NIR light via a sequential multiphoton absorption process referred to as upconversion. NIR light can penetrate up to few cm inside tissues, thus making these UCNPs much better probes than conventional fluorophores for in vivo monitoring. Also, UCNPs have narrow emission bands, high photoluminescence (PL) signal-to-noise ratio, low cytotoxicity and good physical and chemical stability. Here, we show a nanocomposite system consisting of a biodegradable, in situ thermogelling injectable hydrogel made of chitosan and hyaluronic acid encapsulating silica-coated LiYF4:Yb(3+)/Tm(3+) UCNPs. We use these UCNPs as photoluminescent tags to monitor the gel degradation inside live, cultured intervertebral discs (IVDs) over a period of 3 weeks. PL spectroscopy and NIR imaging show that NIR-to-NIR upconversion of LiYF4:Yb(3+)/Tm(3+)@SiO2 UCNPs allows for tracking of the gel degradation in living tissues. Both in vitro and ex vivo release of UCNPs follow a similar trend during the first 5 days; after this time, ex vivo release becomes faster than in vitro, indicating a faster gel degradation ex vivo. Also, the amount of released UCNPs in vitro increases continuously up to 3 weeks, while it plateaus after 15 days inside the IVDs showing a homogenous distribution of UCNPs throughout the IVD tissue. This non-invasive optical method for real time, live tissue imaging holds

  11. Green Synthesis of Robust, Biocompatible Silver Nanoparticles Using Garlic Extract

    International Nuclear Information System (INIS)

    This paper details a facile approach for the synthesis of stable and monodisperse silver nanoparticles performed at ambient/low temperature, where Allium sativum (garlic) extract functions as the silver salt reducing agent during nanoparticle synthesis as well as the post synthesis stabilizing ligands. Varying the synthesis conditions provides control of particle size, size-distribution, and kinetics of particle formation. Infrared spectroscopy, energy dispersive X-ray chemical analysis, and high-performance liquid chromatography indicated that allicin and other carbohydrates in the garlic extract are the primary nanoparticle stabilizing moieties. The synthesized silver nanoparticles also demonstrate potential for biomedical applications, owing to (1) enhanced stability in biological media, (2) resistance to oxidation by the addition of H2O2, (3) ease and scalability of synthesis, and (4) lack of harsh chemicals required for synthesis. Cytotoxicity assays indicated no decrease in cellular proliferation for vascular smooth muscle cells and 3T3 fibroblasts at a concentration of 25 μg/mL, confirming that silver nanoparticles synthesized with garlic extract are potential candidates for future experimentation and implementation in the biomedical field.

  12. Facile Synthesis of Biocompatible Fluorescent Nanoparticles for Cellular Imaging and Targeted Detection of Cancer Cells.

    Science.gov (United States)

    Tang, Fu; Wang, Chun; Wang, Xiaoyu; Li, Lidong

    2015-11-18

    In this work, we report the facile synthesis of functional core-shell structured nanoparticles with fluorescence enhancement, which show specific targeting of cancer cells. Biopolymer poly-l-lysine was used to coat the silver core with various shell thicknesses. Then, the nanoparticles were functionalized with folic acid as a targeting agent for folic acid receptor. The metal-enhanced fluorescence effect was observed when the fluorophore (5-(and-6)-carboxyfluorescein-succinimidyl ester) was conjugated to the modified nanoparticle surface. Cellular imaging assay of the nanoparticles in folic acid receptor-positive cancer cells showed their excellent biocompatibility and selectivity. The as-prepared functional nanoparticles demonstrate the efficiency of the metal-enhanced fluorescence effect and provide an alternative approach for the cellular imaging and targeting of cancer cells.

  13. Reducing the cytotoxicity of inhalable engineered nanoparticles via in situ passivation with biocompatible materials

    International Nuclear Information System (INIS)

    Highlights: • The cytotoxicity of model welding particles was modulated through in situ passivation. • Model welding particles were incorporated with chitosan nanoparticles for passivation. • In vitro assay revealed that the passivated particles had a lower cytotoxicity. • Passivation with chitosan adhesive or graphite paste could also reduce cytotoxicity. • This method would be suitable for efficient reduction of inhalable toxic components. - Abstract: The cytotoxicity of model welding nanoparticles was modulated through in situ passivation with soluble biocompatible materials. A passivation process consisting of a spark discharge particle generator coupled to a collison atomizer as a co-flow or counter-flow configuration was used to incorporate the model nanoparticles with chitosan. The tested model welding nanoparticles are inhaled and that A549 cells are a human lung epithelial cell line. Measurements of in vitro cytotoxicity in A549 cells revealed that the passivated nanoparticles had a lower cytotoxicity (>65% in average cell viability, counter-flow) than the untreated model nanoparticles. Moreover, the co-flow incorporation between the nanoparticles and chitosan induced passivation of the nanoparticles, and the average cell viability increased by >80% compared to the model welding nanoparticles. As a more convenient way (additional chitosan generation and incorporation devices may not be required), other passivation strategies through a modification of the welding rod with chitosan adhesive and graphite paste did also enhance average cell viability (>58%). The approach outlined in this work is potentially generalizable as a new platform, using only biocompatible materials in situ, to treat nanoparticles before they are inhaled

  14. Reducing the cytotoxicity of inhalable engineered nanoparticles via in situ passivation with biocompatible materials

    Energy Technology Data Exchange (ETDEWEB)

    Byeon, Jeong Hoon, E-mail: postjb@yu.ac.kr [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Park, Jae Hong; Peters, Thomas M. [Department of Occupational and Environmental Health, University of Iowa, IA 52242 (United States); Roberts, Jeffrey T., E-mail: jtrob@purdue.edu [Department of Chemistry, Purdue University, IN 47907 (United States)

    2015-07-15

    Highlights: • The cytotoxicity of model welding particles was modulated through in situ passivation. • Model welding particles were incorporated with chitosan nanoparticles for passivation. • In vitro assay revealed that the passivated particles had a lower cytotoxicity. • Passivation with chitosan adhesive or graphite paste could also reduce cytotoxicity. • This method would be suitable for efficient reduction of inhalable toxic components. - Abstract: The cytotoxicity of model welding nanoparticles was modulated through in situ passivation with soluble biocompatible materials. A passivation process consisting of a spark discharge particle generator coupled to a collison atomizer as a co-flow or counter-flow configuration was used to incorporate the model nanoparticles with chitosan. The tested model welding nanoparticles are inhaled and that A549 cells are a human lung epithelial cell line. Measurements of in vitro cytotoxicity in A549 cells revealed that the passivated nanoparticles had a lower cytotoxicity (>65% in average cell viability, counter-flow) than the untreated model nanoparticles. Moreover, the co-flow incorporation between the nanoparticles and chitosan induced passivation of the nanoparticles, and the average cell viability increased by >80% compared to the model welding nanoparticles. As a more convenient way (additional chitosan generation and incorporation devices may not be required), other passivation strategies through a modification of the welding rod with chitosan adhesive and graphite paste did also enhance average cell viability (>58%). The approach outlined in this work is potentially generalizable as a new platform, using only biocompatible materials in situ, to treat nanoparticles before they are inhaled.

  15. Correction: Polyol synthesis, functionalisation, and biocompatibility studies of superparamagnetic iron oxide nanoparticles as potential MRI contrast agents

    Science.gov (United States)

    Hachani, Roxanne; Lowdell, Mark; Birchall, Martin; Hervault, Aziliz; Mertz, Damien; Begin-Colin, Sylvie; Thanh, Nguy&Ecirtil; N. Thi&Cmb. B. Dot; Kim

    2016-02-01

    Correction for `Polyol synthesis, functionalisation, and biocompatibility studies of superparamagnetic iron oxide nanoparticles as potential MRI contrast agents' by Roxanne Hachani et al., Nanoscale, 2015, DOI: 10.1039/c5nr03867g.

  16. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    Science.gov (United States)

    Sharma, Anshu; Baral, Dinesh; Rawat, Kamla; Solanki, Pratima R.; Bohidar, H. B.

    2015-05-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe3O4)) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe3O4 and CA-Fe3O4/ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe3O4, CA-Fe3O4 nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe3O4) and 189.51 nm (CA-Fe3O4) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe2O3/ITO immunosensor exhibits a good detection range of 12.5-500 ng mL-1 with a low detection limit of 0.32 ng mL-1, sensitivity 0.03 Ω/ng ml-1 cm-2, and reproducibility more than 11 times.

  17. Photophysical properties and biocompatibility of Photoluminescent Y2O3:Eu nanoparticles in polymethylmetacrylate matrix.

    Science.gov (United States)

    Abe, Shigeaki; Hamba, Yusuke; Iwadera, Nobuki; Yamagata, Shuichi; Yawaka, Yasutaka; Uo, Motohiro; Iida, Junichiro; Kiba, Takayuki; Murayama, Akihiro; Watari, Fumio

    2014-04-01

    In this study, we produced europium-doped yttoria (Y2O3:Eu) nanoparticles and investigated their photoluminescent properties and biocompatibility. The Y2O3:Eu nanoparticles showed excellent photoluminescent properties and cytocompatibility. We also analyzed the photophysical properties of the nanoparticles in PMMA films. When the Y2O3:Eu nanoparticles were incorporated in the polymer film, they showed a strong red emission spectrum, similar to that seen with the particles alone. Energy dispersive X-ray spectroscopy (EDS) measurements indicated that the particles were distributed homogeneously in the PMMA film. Such materials could be applied not only to optoelectronic devices but also to biomedical applications such as bioimaging tools or luminescent medical/dental adhesive materials. PMID:24734706

  18. BSA-directed synthesis of CuS nanoparticles as a biocompatible photothermal agent for tumor ablation in vivo.

    Science.gov (United States)

    Zhang, Cai; Fu, Yan-Yan; Zhang, Xuejun; Yu, Chunshui; Zhao, Yan; Sun, Shao-Kai

    2015-08-01

    Photothermal therapy as a physical therapeutic approach has greatly attracted research interest due to its negligible systemic effects. Among the various photothermal agents, CuS nanoparticles have been widely used due to their easy preparation, low cost, high stability and strong absorption in the NIR region. However, the ambiguous biotoxicity of CuS nanoparticles limited their bio-application. So it is highly desirable to develop biocompatible CuS photothermal agents with the potential of clinical translation. Herein, we report a novel method to synthesize biocompatible CuS nanoparticles for photothermal therapy using bovine serum albumin (BSA) as a template via mimicking biomaterialization processes. Owing to the inherent biocompatibility of BSA, the toxicity assays in vitro and in vivo showed that BSA-CuS nanoparticles possessed good biocompatibility. In vitro and in vivo photothermal therapies were performed and good results were obtained. The bulk of the HeLa cells treated with BSA-CuS nanoparticles under laser irradiation (808 nm) were killed, and the tumor tissues of mice were also successfully eliminated without causing any obvious systemic damage. In summary, a novel strategy for the synthesis of CuS nanoparticles was developed using BSA as the template, and the excellent biocompatibility and efficient photothermal therapy effects of BSA-CuS nanoparticles show great potential as an ideal photothermal agent for cancer treatment.

  19. Biocompatibility assessment of rice husk-derived biogenic silica nanoparticles for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Alshatwi, Ali A., E-mail: alshatwi@ksu.edu.sa; Athinarayanan, Jegan; Periasamy, Vaiyapuri Subbarayan

    2015-02-01

    Synthetic forms of silica have low biocompatibility, whereas biogenic forms have myriad beneficial effects in current toxicological applications. Among the various sources of biogenic silica, rice husk is considered a valuable agricultural biomass material and a cost-effective resource that can provide biogenic silica for biomedical applications. In the present study, highly pure biogenic silica nanoparticles (bSNPs) were successfully harvested from rice husks using acid digestion under pressurized conditions at 120 °C followed by a calcination process. The obtained bSNPs were subjected to phase identification analysis using X-ray diffraction, which revealed the amorphous nature of the bSNPs. The morphologies of the bSNPs were observed using transmission electron microscopy (TEM), which revealed spherical particles 10 to 30 nm in diameter. Furthermore, the biocompatibility of the bSNPs with human lung fibroblast cells (hLFCs) was investigated using a viability assay and assessing cellular morphological changes, intracellular ROS generation, mitochondrial transmembrane potential and oxidative stress-related gene expression. Our results revealed that the bSNPs did not have any significant incompatibility in these in vitro cell-based approaches. These preliminary findings suggest that bSNPs are biocompatible, could be the best alternative to synthetic forms of silica and are applicable to food additive and biomedical applications. - Highlights: • Simple, rapid and convenient process • Amorphous and spherical with 10–30 nm size SiO{sub 2} nanoparticles were fabricated. • Biogenic silica nanoparticles showed biocompatibility. • bSNPs are an alternative to synthetic forms of silica.

  20. Biocompatible Metal-Oxide Nanoparticles: Nanotechnology Improvement of Conventional Prosthetic Acrylic Resins

    Directory of Open Access Journals (Sweden)

    Laura S. Acosta-Torres

    2011-01-01

    Full Text Available Nowadays, most products for dental restoration are produced from acrylic resins based on heat-cured Poly(Methyl MethAcrylate (PMMA. The addition of metal nanoparticles to organic materials is known to increase the surface hydrophobicity and to reduce adherence to biomolecules. This paper describes the use of nanostructured materials, TiO2 and Fe2O3, for simultaneously coloring and/or improving the antimicrobial properties of PMMA resins. Nanoparticles of metal oxides were included during suspension polymerization to produce hybrid metal oxides-alginate-containing PMMA. Metal oxide nanoparticles were characterized by dynamic light scattering, and X-ray diffraction. Physicochemical characterization of synthesized resins was assessed by a combination of spectroscopy, scanning electron microscopy, viscometry, porosity, and mechanical tests. Adherence of Candida albicans cells and cellular compatibility assays were performed to explore biocompatibility and microbial adhesion of standard and novel materials. Our results show that introduction of biocompatible metal nanoparticles is a suitable means for the improvement of conventional acrylic dental resins.

  1. Synthesis, characterization and biocompatibility of ``green'' synthesized silver nanoparticles using tea polyphenols

    Science.gov (United States)

    Moulton, Michael C.; Braydich-Stolle, Laura K.; NadagoudaPresent Address: Pegasus Technical Services, 46 E. Hollister Street, Cincinnati, 45219, Ohio, Usa., Mallikarjuna N.; Kunzelman, Samantha; Hussain, Saber M.; Varma, Rajender S.

    2010-05-01

    Since ancient times, people have taken advantage of the antimicrobial effects of colloidal silver particles. Aside from the medical prospects, silver nanoparticles are found in a wide range of commercially available consumer products ranging from cosmetics to household cleansers. Current synthetic methods for creating silver nanoparticles typically call for potentially hazardous chemicals, extreme heat, and produce environmentally dangerous byproducts. Therefore, it is essential that novel ``green'' synthesis of nanoparticles becomes a reality, and it is imperative to fully analyze the potential toxic effects of these nanoparticles. In this study, we have shown that by reducing silver nitrate in solutions of tea extract or epicatechin of varying concentrations, spherical silver nanoparticles were formed that had controllable size distributions depending on the concentration of tea extract or epicatechin in the samples. Our ultra-resolution microscopy demonstrated that the nanoparticles were in fact interacting with the keratinocytes. Furthermore, evaluation of mitochondrial function (MTS) to assess cell viability and membrane integrity (LDH) in human keratinocytes showed that the silver nanoparticles were nontoxic. These results demonstrated that these nanoparicles are potentially biocompatible and warrant further evaluation in other biological systems.

  2. Synthesis, characterization and biocompatibility of "green" synthesized silver nanoparticles using tea polyphenols.

    Science.gov (United States)

    Moulton, Michael C; Braydich-Stolle, Laura K; Nadagouda, Mallikarjuna N; Kunzelman, Samantha; Hussain, Saber M; Varma, Rajender S

    2010-05-01

    Since ancient times, people have taken advantage of the antimicrobial effects of colloidal silver particles. Aside from the medical prospects, silver nanoparticles are found in a wide range of commercially available consumer products ranging from cosmetics to household cleansers. Current synthetic methods for creating silver nanoparticles typically call for potentially hazardous chemicals, extreme heat, and produce environmentally dangerous byproducts. Therefore, it is essential that novel "green" synthesis of nanoparticles becomes a reality, and it is imperative to fully analyze the potential toxic effects of these nanoparticles. In this study, we have shown that by reducing silver nitrate in solutions of tea extract or epicatechin of varying concentrations, spherical silver nanoparticles were formed that had controllable size distributions depending on the concentration of tea extract or epicatechin in the samples. Our ultra-resolution microscopy demonstrated that the nanoparticles were in fact interacting with the keratinocytes. Furthermore, evaluation of mitochondrial function (MTS) to assess cell viability and membrane integrity (LDH) in human keratinocytes showed that the silver nanoparticles were nontoxic. These results demonstrated that these nanoparicles are potentially biocompatible and warrant further evaluation in other biological systems. PMID:20648322

  3. Biocompatibility of hydrophilic silica-coated CdTe quantum dots and magnetic nanoparticles

    Science.gov (United States)

    Ruan, Jing; Wang, Kan; Song, Hua; Xu, Xin; Ji, Jiajia; Cui, Daxiang

    2011-12-01

    Fluorescent magnetic nanoparticles exhibit great application prospects in biomedical engineering. Herein, we reported the effects of hydrophilic silica-coated CdTe quantum dots and magnetic nanoparticles (FMNPs) on human embryonic kidney 293 (HEK293) cells and mice with the aim of investigating their biocompatibility. FMNPs with 150 nm in diameter were prepared, and characterized by high-resolution transmission electron microscopy and photoluminescence (PL) spectra and magnetometer. HEK293 cells were cultured with different doses of FMNPs (20, 50, and 100μ g/ml) for 1-4 days. Cell viability and adhesion ability were analyzed by CCK8 method and Western blotting. 30 mice were randomly divided into three groups, and were, respectively, injected via tail vein with 20, 60, and 100 μg FMNPs, and then were, respectively, raised for 1, 7, and 30 days, then their lifespan, important organs, and blood biochemical parameters were analyzed. Results show that the prepared water-soluble FMNPs had high fluorescent and magnetic properties, less than 50 μg/ml of FMNPs exhibited good biocompatibility to HEK293 cells, the cell viability, and adhesion ability were similar to the control HEK293 cells. FMNPs primarily accumulated in those organs such as lung, liver, and spleen. Lung exposed to FMNPs displayed a dose-dependent inflammatory response, blood biochemical parameters such as white blood cell count (WBC), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), displayed significant increase when the FMNPs were injected into mice at dose of 100μg. In conclusion, FMNPs exhibit good biocompatibility to cells under the dose of less than 50 μg/ml, and to mice under the dose of less than 2mg/kg body weight. The FMNPs' biocompatibility must be considered when FMNPs are used for in vivo diagnosis and therapy.

  4. Biocompatibility of hydrophilic silica-coated CdTe quantum dots and magnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Ruan Jing

    2011-01-01

    Full Text Available Abstract Fluorescent magnetic nanoparticles exhibit great application prospects in biomedical engineering. Herein, we reported the effects of hydrophilic silica-coated CdTe quantum dots and magnetic nanoparticles (FMNPs on human embryonic kidney 293 (HEK293 cells and mice with the aim of investigating their biocompatibility. FMNPs with 150 nm in diameter were prepared, and characterized by high-resolution transmission electron microscopy and photoluminescence (PL spectra and magnetometer. HEK293 cells were cultured with different doses of FMNPs (20, 50, and 100μ g/ml for 1-4 days. Cell viability and adhesion ability were analyzed by CCK8 method and Western blotting. 30 mice were randomly divided into three groups, and were, respectively, injected via tail vein with 20, 60, and 100 μg FMNPs, and then were, respectively, raised for 1, 7, and 30 days, then their lifespan, important organs, and blood biochemical parameters were analyzed. Results show that the prepared water-soluble FMNPs had high fluorescent and magnetic properties, less than 50 μg/ml of FMNPs exhibited good biocompatibility to HEK293 cells, the cell viability, and adhesion ability were similar to the control HEK293 cells. FMNPs primarily accumulated in those organs such as lung, liver, and spleen. Lung exposed to FMNPs displayed a dose-dependent inflammatory response, blood biochemical parameters such as white blood cell count (WBC, alanine aminotransferase (ALT, and aspartate aminotransferase (AST, displayed significant increase when the FMNPs were injected into mice at dose of 100μg. In conclusion, FMNPs exhibit good biocompatibility to cells under the dose of less than 50 μg/ml, and to mice under the dose of less than 2mg/kg body weight. The FMNPs' biocompatibility must be considered when FMNPs are used for in vivo diagnosis and therapy.

  5. Preparation of Biocompatible Carboxymethyl Chitosan Nanoparticles for Delivery of Antibiotic Drug

    Directory of Open Access Journals (Sweden)

    Liang Zhao

    2013-01-01

    Full Text Available Objective. To prepare biocompatible ciprofloxacin-loaded carboxymethyl chitosan nanoparticles (CCC NPs and evaluate their cell specificity as well as antibacterial activity against Escherichia coli in vitro. Methods. CCC NPs were prepared by ionic cross-linking method and optimized by using Box-Behnken response surface method (BBRSM. Zeta potential, drug encapsulation, and release of the obtained nanoparticles in vitro were thoroughly investigated. Minimum inhibitory concentration (MIC and killing profiles of free or ciprofloxacin-loaded nanoparticles against Escherichia coli were documented. The cytotoicity of blank nanoparticles and cellular uptake of CCC NPs were also investigated. Results. The obtained particles were monodisperse nanospheres with an average hydrated diameter of 151 ± 5.67 nm and surface of charge −22.9 ± 2.21 mV. The MICs of free ciprofloxacin and CCC NPs were 0.16 and 0.08 μg/mL, respectively. Blank nanoparticles showed no obvious cell inhibition within 24 h, and noticeable phagocytosis effect was observed in the presence of CCC NPs. Conclusion. This study shows that CCC NPs have stronger antibacterial activity against Escherichia coli than the free ciprofloxacin because they can easily be uptaken by cells. The obtained CCC NPs have promising prospect in drug delivery field.

  6. Time-dependent biodistribution, clearance and biocompatibility of magnetic fibrin nanoparticles: an in vivo study

    Science.gov (United States)

    Prabu, Periyathambi; Vedakumari, Weslen S.; Sastry, Thotapalli P.

    2015-05-01

    Recently, bioretention and toxicity of injected nanoparticles in the body has drawn much attention in biomedical research. In the present study, 5 mg Fe per kg body weight of magnetic fibrin nanoparticles (MFNPs) were injected into mice intravenously and investigated for their blood clearance profile, biodistribution, haematology and pathology studies for a time period of 28 days. Moderately long circulation of MFNPs in blood was observed with probable degradation and excretion into the bloodstream via monoatomic iron forms. Inductively coupled plasma optical emission spectrometry (ICP-OES) and Prussian blue staining results showed increased accumulation of MFNPs in the liver, followed by spleen and other organs. Body weight, spleen/thymus indexes, haematology, serum biochemistry and histopathology studies demonstrated that MFNPs were biocompatible. These results suggest the feasibility of using MFNPs for drug delivery and imaging applications.

  7. Polyol synthesis, functionalisation, and biocompatibility studies of superparamagnetic iron oxide nanoparticles as potential MRI contrast agents

    Science.gov (United States)

    Hachani, Roxanne; Lowdell, Mark; Birchall, Martin; Hervault, Aziliz; Mertz, Damien; Begin-Colin, Sylvie; Thanh, Nguy&Ecirtil; N. Thi&Cmb. B. Dot; Kim

    2016-02-01

    Iron oxide nanoparticles (IONPs) of low polydispersity were obtained through a simple polyol synthesis in high pressure and high temperature conditions. The control of the size and morphology of the nanoparticles was studied by varying the solvent used, the amount of iron precursor and the reaction time. Compared with conventional synthesis methods such as thermal decomposition or co-precipitation, this process yields nanoparticles with a narrow particle size distribution in a simple, reproducible and cost effective manner without the need for an inert atmosphere. For example, IONPs with a diameter of ca. 8 nm could be made in a reproducible manner and with good crystallinity as evidenced by X-ray diffraction analysis and high saturation magnetization value (84.5 emu g-1). The surface of the IONPs could be tailored post synthesis with two different ligands which provided functionality and stability in water and phosphate buffer saline (PBS). Their potential as a magnetic resonance imaging (MRI) contrast agent was confirmed as they exhibited high r1 and r2 relaxivities of 7.95 mM-1 s-1 and 185.58 mM-1 s-1 respectively at 1.4 T. Biocompatibility and viability of IONPs in primary human mesenchymal stem cells (hMSCs) was studied and confirmed.Iron oxide nanoparticles (IONPs) of low polydispersity were obtained through a simple polyol synthesis in high pressure and high temperature conditions. The control of the size and morphology of the nanoparticles was studied by varying the solvent used, the amount of iron precursor and the reaction time. Compared with conventional synthesis methods such as thermal decomposition or co-precipitation, this process yields nanoparticles with a narrow particle size distribution in a simple, reproducible and cost effective manner without the need for an inert atmosphere. For example, IONPs with a diameter of ca. 8 nm could be made in a reproducible manner and with good crystallinity as evidenced by X-ray diffraction analysis and high

  8. Development of a lauric acid/albumin hybrid iron oxide nanoparticle system with improved biocompatibility.

    Science.gov (United States)

    Zaloga, Jan; Janko, Christina; Nowak, Johannes; Matuszak, Jasmin; Knaup, Sabine; Eberbeck, Dietmar; Tietze, Rainer; Unterweger, Harald; Friedrich, Ralf P; Duerr, Stephan; Heimke-Brinck, Ralph; Baum, Eva; Cicha, Iwona; Dörje, Frank; Odenbach, Stefan; Lyer, Stefan; Lee, Geoffrey; Alexiou, Christoph

    2014-01-01

    The promising potential of superparamagnetic iron oxide nanoparticles (SPIONs) in various nanomedical applications has been frequently reported. However, although many different synthesis methods, coatings, and functionalization techniques have been described, not many core-shell SPION drug delivery systems are available for clinicians at the moment. Here, bovine serum albumin was adsorbed onto lauric acid-stabilized SPIONs. The agglomeration behavior, zeta potential, and their dependence on the synthesis conditions were characterized with dynamic light scattering. The existence and composition of the core-shell-matrix structure was investigated by transmission electron microscopy, Fourier transform infrared spectroscopy, and zeta potential measurements. We showed that the iron oxide cores form agglomerates in the range of 80 nm. Moreover, despite their remarkably low tendency to aggregate even in a complex media like whole blood, the SPIONs still maintained their magnetic properties and were well attractable with a magnet. The magnetic properties were quantified by vibrating sample magnetometry and a superconducting quantum interference device. Using flow cytometry, we further investigated the effects of the different types of nanoparticle coating on morphology, viability, and DNA integrity of Jurkat cells. We showed that by addition of bovine serum albumin, the toxicity of nanoparticles is greatly reduced. We also investigated the effect of the particles on the growth of primary human endothelial cells to further demonstrate the biocompatibility of the particles. As proof of principle, we showed that the hybrid-coated particles are able to carry payloads of up to 800 μg/mL of the cytostatic drug mitoxantrone while still staying colloidally stable. The drug-loaded system exhibited excellent therapeutic potential in vitro, exceeding that of free mitoxantrone. In conclusion, we have synthesized a biocompatible ferrofluid that shows great potential for clinical

  9. Biocompatible PEGylated Fe3O4 Nanoparticles as Photothermal Agents for Near-Infrared Light Modulated Cancer Therapy

    OpenAIRE

    Gang Yuan; Yongjie Yuan; Kan Xu; Qi Luo

    2014-01-01

    In accordance with the World Cancer Report, cancer has become the leading cause of mortality worldwide, and various therapeutic strategies have been developed at the same time. In the present study, biocompatible magnetic nanoparticles were designed and synthesized as high-performance photothermal agents for near-infrared light mediated cancer therapy in vitro. Via a facile one-pot solvothermal method, well-defined PEGylated magnetic nanoparticles (PEG–Fe3O4) were prepared with cheap inhesion...

  10. Synthesis, characterization and biocompatibility of cadmium sulfide nanoparticles capped with dextrin for in vivo and in vitro imaging application

    OpenAIRE

    Reyes-Esparza, Jorge; Martínez-Mena, Alberto; Gutiérrez-Sancha, Ivonne; Rodríguez-Fragoso, Patricia; de la Cruz, Gerardo Gonzalez; Mondragón, R.; Rodríguez-Fragoso, Lourdes

    2015-01-01

    Background The safe use in biomedicine of semiconductor nanoparticles, also known as quantum dots (QDs), requires a detailed understanding of the biocompatibility and toxicity of QDs in human beings. The biological characteristics and physicochemical properties of QDs entail new challenges regarding the management of potential adverse health effects following exposure. At certain concentrations, the synthesis of semiconductor nanoparticles of CdS using dextrin as capping agent, at certain con...

  11. Novel biocompatible hydrogel nanoparticles: generation and size-tuning of nanoparticles by the formation of micelle templates obtained from thermo-responsive monomers mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Khandadash, Raz; Machtey, Victoria [Bar Ilan University, Department of Chemistry (Israel); Shainer, Inbal [Tel-Aviv University, Department of Neurobiology, The George S. Wise Faculty of Life Sciences (Israel); Gottlieb, Hugo E. [Bar Ilan University, Department of Chemistry (Israel); Gothilf, Yoav [Tel-Aviv University, Department of Neurobiology, The George S. Wise Faculty of Life Sciences, and Sagol School of Neuroscience (Israel); Ebenstein, Yuval [Tel Aviv University, Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry (Israel); Weiss, Aryeh [Bar Ilan University, School of Engineering (Israel); Byk, Gerardo, E-mail: gerardo.byk@biu.ac.il [Bar Ilan University, Department of Chemistry (Israel)

    2014-12-15

    Biocompatible hydrogel nanoparticles are prepared by polymerization and cross-linking of N-isopropyl acrylamide in a micelle template formed by block copolymers macro-monomers at high temperature. Different monomer ratios form, at high temperature, well-defined micelles of different sizes which are further polymerized leading to nanoparticles with varied sizes from 20 to 390 nm. Physico-chemical characterization of the nanoparticles demonstrates their composition and homogeneity. The NPs were tested in vitro and in vivo biocompatibility assays, and their lack of toxicity was proven. The NPs can be labeled with fluorescent probes, and their intracellular fate can be visualized and quantified using confocal microscopy. Their uptake by live stem cells and distribution in whole developing animals is reported. On the basis of our results, a mechanism of nanoparticle formation is suggested. The lack of toxicity makes these nanoparticles especially attractive for biological applications such as screening and bio-sensing.

  12. Biocompatibility of magnetic Fe3O4 nanoparticles and their cytotoxic effect on MCF-7 cells

    Directory of Open Access Journals (Sweden)

    Chen DZ

    2012-09-01

    Full Text Available Daozhen Chen,1,3,* Qiusha Tang,2,* Xiangdong Li,3,* Xiaojin Zhou,1 Jia Zang,1 Wen-qun Xue,1 Jing-ying Xiang,1 Cai-qin Guo11Central Laboratory, Wuxi Hospital for Matemaland Child Health Care Affiliated Medical School of Nanjing, Jiangsu Province; 2Department of Pathology and Pathophysiology, Medical College, Southeast University, Jiangsu Province; 3The People’s Hospital of Aheqi County, Xinjiang, China *These authors contributed equally to this workBackground: The objective of this study was to evaluate the synthesis and biocompatibility of Fe3O4 nanoparticles and investigate their therapeutic effects when combined with magnetic fluid hyperthermia on cultured MCF-7 cancer cells.Methods: Magnetic Fe3O4 nanoparticles were prepared using a coprecipitation method. The appearance, structure, phase composition, functional groups, surface charge, magnetic susceptibility, and release in vitro were characterized by transmission electron microscopy, x-ray diffraction, scanning electron microscopy-energy dispersive x-ray spectroscopy, and a vibrating sample magnetometer. Blood toxicity, in vitro toxicity, and genotoxicity were investigated. Therapeutic effects were evaluated by MTT [3-(4, 5-dimethyl-2-thiazolyl-2, 5-diphenyl-2H-tetrazolium bromide] and flow cytometry assays.Results: Transmission electron microscopy revealed that the shapes of the Fe3O4 nanoparticles were approximately spherical, with diameters of about 26.1 ± 5.2 nm. Only the spinel phase was indicated in a comparison of the x-ray diffraction data with Joint Corporation of Powder Diffraction Standards (JCPDS X-ray powder diffraction files. The O-to-Fe ratio of the Fe3O4 was determined by scanning electron microscopy-energy dispersive x-ray spectroscopy elemental analysis, and approximated pure Fe3O4. The vibrating sample magnetometer hysteresis loop suggested that the Fe3O4 nanoparticles were superparamagnetic at room temperature. MTT experiments showed that the toxicity of the material

  13. The Preparation and Biocompatibility Study on Fe2O3 Magnetic Nanoparticles Used in Tumor Hyperthermia

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective:To evaluate the in vitro and in vivo toxicity of self-prepared nanosized Fe2 O3, which has the potential implication in tumor hyperthermia. Methods:Fe2O3 nanoparticles were prepared by improving co-precipitation, which characterization was detected by TEM, XRD, CMIAS, EDS. MTT assay was used to evaluate the in vitro cytotoxicity test; hemolytic test was carried out to estimate whether it has blood toxicity;Fe2O3 suspended in sterile 0.9% NaCl was intraperitoneally injected into Kunming mouse to calculate the LD50; micronucleus (MN) were reckoned to identify whether it is genotoxic. Results :The nanoparticles are brown spherical particles with diameter ranging from 8 to 15 nm, which have good decentralization and stability. The experiments also showed that the toxicity of the material on mouse fibroblast (L-929) cell lines was 0 - 1 degree; it has no hemolysis activity; LD50 arrived at 5.45 g/kg-1 after intraperitoneal injection of 1 ml suspension; micronucleus test showed that it has no genotoxic effects either. Conclusion:The results showed that the Fe2O3 nanoparticles are prepared successfully, the self-prepared nanosized Fe2O3 is a kind of high biocompatibility materials and perhaps it is suitable for further application in tumor hyperthermia.

  14. Biocompatibility study of two diblock copolymeric nanoparticles for biomedical applications by in vitro toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Goñi-de-Cerio, Felipe [GAIKER Technology Centre (Spain); Mariani, Valentina [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Cohen, Dror [Dead Sea Laboratories, AHAVA (Israel); Madi, Lea [Tel-Aviv University, Department of Physiology and Pharmacology, Sackler School of Medicine (Israel); Thevenot, Julie; Oliveira, Hugo [ENSCPB, Université de Bordeaux (France); Uboldi, Chiara; Giudetti, Guido; Coradeghini, Rosella [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Garanger, Elisabeth [ENSCPB, Université de Bordeaux (France); Rossi, François [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Portugal-Cohen, Meital; Oron, Miriam [Dead Sea Laboratories, AHAVA (Israel); Korenstein, Rafi [Tel-Aviv University, Department of Physiology and Pharmacology, Sackler School of Medicine (Israel); Lecommandoux, Sébastien [ENSCPB, Université de Bordeaux (France); Ponti, Jessica [European Commission, Nanobiosciences Unit, Institute for Health and Consumer Protection, Joint Research Centre (Italy); Suárez-Merino, Blanca; Heredia, Pedro, E-mail: heredia@gaiker.es [GAIKER Technology Centre (Spain)

    2013-11-15

    Drugs used for chemotherapy normally carry out adverse, undesired effects. Nanotechnology brings about new horizons to tackle cancer disease with a different strategy. One of the most promising approaches is the use of nanocarriers to transport active drugs. These nanocarriers need to have special properties to avoid immune responses and toxicity, and it is critical to study these effects. Nanocarriers may have different nature, but polypeptide-based copolymers have attracted considerable attention for their biocompatibility, controlled and slow biodegradability as well as low toxicity. Little has been done regarding specific nanocarriers toxicity. In this study, we performed a thorough toxicological study of two different block copolymer nanoparticles (NPs); poly(trimethylene carbonate)-block–poly(l-glutamic acid) (PTMC-b–PGA) and poly(ethylene glycol)-block–poly(γ-benzyl-l-glutamate) (PEG-b–PBLG) with sizes between 113 and 131 nm. Low blood–serum–protein interaction was observed. Moreover, general toxicity assays and other endpoints (apoptosis or necrosis) showed good biocompatibility for both NPs. Reactive oxygen species increased in only two cell lines (HepG2 and TK6) in the presence of PTMC-b–PGA. Cytokine production study showed cytokine induction only in one cell line (A549). We also performed the same assays on human skin organ culture before and after UVB light treatment, with a moderate toxicity after treatment independent of NPs presence or absence. Interleukin 1 induction was also observed due to the combined effect of PEG-b–PBLG and UVB light irradiation. Future in vivo studies for biocompatibility and toxicity will provide more valuable information, but, so far, the findings presented here suggest the possibility of using these two NPs as nanocarriers for nanomedical applications, always taking into account the application procedure and the way in which they are implemented.

  15. Evaluation of the antibacterial activity and biocompatibility for silver nanoparticles immobilized on nano silicate platelets.

    Science.gov (United States)

    Lin, Jiang-Jen; Lin, Wen-Chun; Li, Shing-Da; Lin, Cheng-Yen; Hsu, Shan-hui

    2013-01-23

    Silver nanoparticles (AgNPs) are known for their bactericidal abilities. The antibacterial potency is dependent on the particle size and dispersion status. In this study, we synthesized AgNP/NSP nanohybrids in two different weight ratios (1/99 and 8/92) using the fully exfoliated clay, i.e., nanosilicate platelets (NSP), as a dispersing agent and carrier for AgNPs. Due to the size of NSP, the immobilized AgNPs do not enter cells readily, which may lower the risk associated with the cellular uptake of AgNPs. The biocompatibility, immunological response, and antimicrobial activities of AgNP/NSP hybrids were evaluated. The results revealed that AgNP/NSP hybrids elicited merely mild inflammatory response and retained the outstanding antibacterial activity. The hybrids were further embedded in poly(ether)urethane (PEU) to increase the biocompatibility. At the same silver content (20 ppm), the PEU-AgNP/NSP nanocomposites were nontoxic to mouse skin fibroblasts, while simultaneously exhibiting nearly complete bacterial growth reduction (99.9%). PEU containing the same amount of free AgNPs did not display such an effect. Our results verify the better biosafety of the AgNPs/NSP hybrids and their polymer nanocomposites for further clinical use.

  16. Different Storage Conditions Influence Biocompatibility and Physicochemical Properties of Iron Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jan Zaloga

    2015-04-01

    Full Text Available Superparamagnetic iron oxide nanoparticles (SPIONs have attracted increasing attention in many biomedical fields. In magnetic drug targeting SPIONs are injected into a tumour supplying artery and accumulated inside the tumour with a magnet. The effectiveness of this therapy is thus dependent on magnetic properties, stability and biocompatibility of the particles. A good knowledge of the effect of storage conditions on those parameters is of utmost importance for the translation of the therapy concept into the clinic and for reproducibility in preclinical studies. Here, core shell SPIONs with a hybrid coating consisting of lauric acid and albumin were stored at different temperatures from 4 to 45 °C over twelve weeks and periodically tested for their physicochemical properties over time. Surprisingly, even at the highest storage temperature we did not observe denaturation of the protein or colloidal instability. However, the saturation magnetisation decreased by maximally 28.8% with clear correlation to time and storage temperature. Furthermore, the biocompatibility was clearly affected, as cellular uptake of the SPIONs into human T-lymphoma cells was crucially dependent on the storage conditions. Taken together, the results show that the particle properties undergo significant changes over time depending on the way they are stored.

  17. Porous silicon nanoparticles as biocompatible contrast agents for magnetic resonance imaging

    Science.gov (United States)

    Gongalsky, M. B.; Kargina, Yu. V.; Osminkina, L. A.; Perepukhov, A. M.; Gulyaev, M. V.; Vasiliev, A. N.; Pirogov, Yu. A.; Maximychev, A. V.; Timoshenko, V. Yu.

    2015-12-01

    We propose porous silicon nanoparticles (PSi NPs) with natural oxide coating as biocompatible and bioresorbable contrast agents for magnetic resonant imaging (MRI). A strong shortening of the transversal proton relaxation time (T2) was observed for aqueous suspensions of PSi NPs, whereas the longitudinal relaxation time (T1) changed moderately. The longitudinal and transversal relaxivities are estimated to be 0.03 and 0.4 l/(g.s), respectively, which are promising for biomedical studies. The proton relaxation is suggested to undergo via the magnetic dipole-dipole interaction with Si dangling bonds on surfaces of PSi NPs. MRI experiments with phantoms have revealed the remarkable contrasting properties of PSi NPs for medical diagnostics.

  18. Porous silicon nanoparticles as biocompatible contrast agents for magnetic resonance imaging

    International Nuclear Information System (INIS)

    We propose porous silicon nanoparticles (PSi NPs) with natural oxide coating as biocompatible and bioresorbable contrast agents for magnetic resonant imaging (MRI). A strong shortening of the transversal proton relaxation time (T2) was observed for aqueous suspensions of PSi NPs, whereas the longitudinal relaxation time (T1) changed moderately. The longitudinal and transversal relaxivities are estimated to be 0.03 and 0.4 l/(g·s), respectively, which are promising for biomedical studies. The proton relaxation is suggested to undergo via the magnetic dipole-dipole interaction with Si dangling bonds on surfaces of PSi NPs. MRI experiments with phantoms have revealed the remarkable contrasting properties of PSi NPs for medical diagnostics

  19. Development of a lauric acid/albumin hybrid iron oxide nanoparticle system with improved biocompatibility

    Directory of Open Access Journals (Sweden)

    Zaloga J

    2014-10-01

    interference device. Using flow cytometry, we further investigated the effects of the different types of nanoparticle coating on morphology, viability, and DNA integrity of Jurkat cells. We showed that by addition of bovine serum albumin, the toxicity of nanoparticles is greatly reduced. We also investigated the effect of the particles on the growth of primary human endothelial cells to further demonstrate the biocompatibility of the particles. As proof of principle, we showed that the hybrid-coated particles are able to carry payloads of up to 800 µg/mL of the cytostatic drug mitoxantrone while still staying colloidally stable. The drug-loaded system exhibited excellent therapeutic potential in vitro, exceeding that of free mitoxantrone. In conclusion, we have synthesized a biocompatible ferrofluid that shows great potential for clinical application. The synthesis is straightforward and reproducible and thus easily translatable into a good manufacturing practice environment. Keywords: iron oxide nanoparticles, drug delivery, protein corona, magnetic drug targeting, colloidal stability

  20. Tea nanoparticle, a safe and biocompatible nanocarrier, greatly potentiates the anticancer activity of doxorubicin.

    Science.gov (United States)

    Wang, Yi-Jun; Huang, Yujian; Anreddy, Nagaraju; Zhang, Guan-Nan; Zhang, Yun-Kai; Xie, Meina; Lin, Derrick; Yang, Dong-Hua; Zhang, Mingjun; Chen, Zhe-Sheng

    2016-02-01

    An infusion-dialysis based procedure has been developed as an approach to isolate organic nanoparticles from green tea. Tea nanoparticle (TNP) can effectively load doxorubicin (DOX) via electrostatic and hydrophobic interactions. We established an ABCB1 overexpressing tumor xenograft mouse model to investigate whether TNP can effectively deliver DOX into tumors and bypass the efflux function of the ABCB1 transporter, thereby increasing the intratumoral accumulation of DOX and potentiating the anticancer activity of DOX. MTT assays suggested that DOX-TNP showed higher cytotoxicity toward CCD-18Co, SW620 and SW620/Ad300 cells than DOX. Animal study revealed that DOX-TNP resulted in greater inhibitory effects on the growth of SW620 and SW620/Ad300 tumors than DOX. In pharmacokinetics study, DOX-TNP greatly increased the SW620 and SW620/Ad300 intratumoral concentrations of DOX. But DOX-TNP had no effect on the plasma concentrations of DOX. Furthermore, TNP is a safe nanocarrier with excellent biocompatibility and minimal toxicity. Ex vivo IHC analysis of SW620 and SW620/Ad300 tumor sections revealed evidence of prominent antitumor activity of DOX-TNP. In conclusion, our findings suggested that natural nanomaterials could be useful in combating multidrug resistance (MDR) in cancer cells and potentiating the anticancer activity of chemotherapeutic agents in cancer treatment. PMID:26716507

  1. Capture Efficiency of Biocompatible Magnetic Nanoparticles in Arterial Flow: A Computer Simulation for Magnetic Drug Targeting.

    Science.gov (United States)

    Lunnoo, Thodsaphon; Puangmali, Theerapong

    2015-12-01

    The primary limitation of magnetic drug targeting (MDT) relates to the strength of an external magnetic field which decreases with increasing distance. Small nanoparticles (NPs) displaying superparamagnetic behaviour are also required in order to reduce embolization in the blood vessel. The small NPs, however, make it difficult to vector NPs and keep them in the desired location. The aims of this work were to investigate parameters influencing the capture efficiency of the drug carriers in mimicked arterial flow. In this work, we computationally modelled and evaluated capture efficiency in MDT with COMSOL Multiphysics 4.4. The studied parameters were (i) magnetic nanoparticle size, (ii) three classes of magnetic cores (Fe3O4, Fe2O3, and Fe), and (iii) the thickness of biocompatible coating materials (Au, SiO2, and PEG). It was found that the capture efficiency of small particles decreased with decreasing size and was less than 5 % for magnetic particles in the superparamagnetic regime. The thickness of non-magnetic coating materials did not significantly influence the capture efficiency of MDT. It was difficult to capture small drug carriers (D<200 nm) in the arterial flow. We suggest that the MDT with high-capture efficiency can be obtained in small vessels and low-blood velocities such as micro-capillary vessels. PMID:26515074

  2. Versatile theranostics agents designed by coating ferrite nanoparticles with biocompatible polymers

    Science.gov (United States)

    Zahraei, M.; Marciello, M.; Lazaro-Carrillo, A.; Villanueva, A.; Herranz, F.; Talelli, M.; Costo, R.; Monshi, A.; Shahbazi-Gahrouei, D.; Amirnasr, M.; Behdadfar, B.; Morales, M. P.

    2016-06-01

    Three biocompatible polymers, polyethylene glycol (PEG), dextran and chitosan, have been used in this work to control the colloidal stability of magnetic nanoparticles (14 ± 5 nm in diameter) and to vary the aggregation state in order to study their effect on relaxometric and heating properties. Two different coating strategies have been deeply developed; one based on the formation of an amide bond between citric acid coated nanoparticles (NPs) and amine groups present on the polymer surface and the other based on the NP encapsulation. Relaxometric properties revealed that proton relaxation rates strongly depend on the coating layer hydrophilicity and the aggregation state of the particles due to the presence of magnetic interactions. Thus, while PEG coating reduces particle aggregation by increasing inter-particle spacing leading to reduction of both T1 and T2 relaxation, dextran and chitosan lead to an increase mainly in T2 values due to the aggregation of particles in bigger clusters where they are in close contact. Dextran and chitosan coated NPs have also shown a remarkable heating effect during the application of an alternating magnetic field. They have proved to be potential candidates as theranostic agents for cancer diagnosis and treatment. Finally, cytotoxicity of PEG conjugated NPs, which seem to be ideal for intravenous administration because of their small hydrodynamic size, was investigated resulting in high cell viability even at 0.2 mg Fe ml-1 after 24 h of incubation. This suspension can be used as drug/biomolecule carrier for in vivo applications.

  3. Biocompatible thermoresponsive PEGMA nanoparticles crosslinked with cleavable disulfide-based crosslinker for dual drug release.

    Science.gov (United States)

    Ulasan, Mehmet; Yavuz, Emine; Bagriacik, Emin Umit; Cengeloglu, Yunus; Yavuz, Mustafa Selman

    2015-01-01

    Smart materials have been attracting much attention because of their stimuli responsive nature. We have synthesized biocompatible thermoresponsive crosslinked poly(ethylene glycol) methyl ether methacrylate (PEGMA)-co-vinyl pyrrolidone nanoparticles (PEGMA NPs) using disulfide-based crosslinker by surfactant-free emulsion polymerization method. Particle characterization studies were carried out by dynamic light scattering, and scanning electron microscopy. Polymerization kinetics, effect of crosslinker and initiator concentrations on both average hydrodynamic diameter and polydispersity index were investigated. Hydrodynamic diameters of thermoresponsive PEGMA NPs were decreased from 210 nm to 90 nm upon heating over the lowest critical solution temperature (LCST). Disulfide crosslinked PEGMA NPs were demonstrated as a dual delivery system. Rhodamine B, a model of small-sized drug molecule, and poly(ethylene glycol) (PEG)-alizarin yellow, a model of large drug molecule, were loaded into PEGMA NPs where LCST of these NPs was tuned to 37°C, the body temperature. The rhodamine B was released from PEGMA NPs upon heating to 39°C. Then, PEG-alizarin content was released by subsequent degradation of nanoparticles using dithiothreitol (DTT), which reduces disulfide bonds to thiols. Furthermore, cytotoxicity studies of PEGMA NPs were carried out in 3T3 cells, which resulted in no toxic effect on the cells.

  4. Nanostructured upconverters for improved solar cell performance

    Science.gov (United States)

    MacQueen, Rowan W.; Schulze, Tim F.; Khoury, Tony; Cheng, Yuen Yap; Stannowski, Bernd; Lips, Klaus; Crossley, Maxwel J.; Schmidt, Timothy

    2013-09-01

    Triplet-triplet annihilation photon upconversion (TTA-UC) is a promising candidate for mitigating sub-band gap absorption losses in solar cells. In TTA-UC, sensitiser dyes absorb sub-band gap photons, cross to a triplet state, and transfer triplet excitons to emitter dyes. Two triplet-excited emitters can undergo TTA, raising one emitter to a higher-energy bright singlet state. The quadratic efficiency of TTA-UC at device-relevant light intensities motivates a push towards the higher chromophore densities achievable in the solid phase. We have begun this process by tethering tetrakisquinoxalino palladium porphyrin to 20nm silica nanoparticles using peptide chemistry techniques, achieving a total-volume concentration of 1.5mM. The phosphorescence kinetics of the tethered porphyrins was measured to quantify quenching by rubrene emitter. Upconverter performance was measured in a solar cell enhancement experiment.

  5. Biocompatibility of artificial bone based on vancomycin loaded mesoporous silica nanoparticles and calcium sulfate composites.

    Science.gov (United States)

    Gu, Jisheng; Wang, Teng; Fan, Guoxin; Ma, Junhua; Hu, Wei; Cai, Xiaobing

    2016-04-01

    The aim of this study was to evaluate the in vitro and in vivo biocompatibility of artificial bone based on vancomycin loaded mesoporous silica nanoparticles and calcium sulfate composites. In vitro cytotoxicity tests by cholecystokinin octapeptide (CCK-8) assay showed that the 5%Van-MSN-CaSO4 and Van-CaSO4 bone cements were cytocompatible for mouse osteoblastic cell line MC3T3-E1. The microscopic observation confirmed that MC3T3-E1cells incubated with Van-CaSO4 group and 5%Van-MSN-CaSO4 group exhibited clear spindle-shaped changes, volume increase and maturation, showing that these cements supported adhesion of osteoblastic cells on their surfaces. In addition, the measurement of alkaline phosphatase activity revealed the osteoconductive property of these biomaterials. In order to assess in vivo biocompatibility, synthesized cements were implanted into the distal femur of twelve adult male and female New Zealand rabbits. After implantation in artificial defects of the distal femur, 5%Van-MSN-CaSO4 and Van-CaSO4 bone cements did not damage the function of main organs of rabbits. In addition, the Van-MSN-CaSO4 composite allowed complete repair of bone defects with new bone formation 3 months after implantation. These results show potential application of Van-MSN-CaSO4 composites as bone graft materials for the treatment of open fracture in human due to its mechanical, osteoconductive and potential sustained drug release characteristics and the absence of adverse effects on the body.

  6. Apoferritin Nanoparticle: A Novel and Biocompatible Carrier for Enzyme Immobilization with Enhanced Activity and Stability

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Youyu; Tang, Zhiwen; Wang, Jun; Wu, Hong J.; Lin, Chiann Tso; Lin, Yuehe

    2011-11-01

    Apoferritin is a nanostructured material with a uniform size and spherical structure, and it has excellent bio-compatibility. In this work, we report the use of apoferritin as a novel and biocompatible carrier for stabilizing enzymes and their activities. We used glucose oxidase (GOx) as a model enzyme. GOx was immobilized on the surface of the apoferritin through a green synthetic approach taking advantage of bioaffinity binding between streptavidin and biotin. As a result, a glucose oxidase-biotin/streptavidin/biotin-apoferritin conjugate (Apo-GOx) was prepared using streptavidin as a bridge. The synthesized Apo-GOx was characterized with transmission electron microscopy, ultraviolet, and fluorescence spectroscopy. The activity and stability of GOx on the surface of the apoferritin were studied in different environments, such as temperature, chemicals, and pH, in comparison with the biotinylated GOx (B-GOx). The results showed that the activity of GOx on the apoferritin surface was significantly enhanced. The thermal and chemical stability of the GOx on the apoferritin was also greatly improved compared to free B-GOx in a solution. It was found that the activity of the GOx on the apoferritin only lost 30% in comparison to a 70% loss of free B-GOx after a 2 h incubation at 50oC. There was almost no decrease in activity for the GOx on the apoferritin as compared to an 80% activity decrease for free B-GOx after 30 min incubation in a 5 M urea solution. Glucose detection was used as a model application for the enzyme immobilization method developed in this work. The GOx immobilized apoferritin nanoparticles exhibited high sensitivity for glucose detection with a detection limit of 3 nM glucose. This work offers a novel approach for immobilizing enzymes with enhanced stability and activity, and this method may find a number of applications, such as in enzyme catalysis, DNA assays and immunoassays.

  7. Preparation of Fluorescent Dye-Doped Biocompatible Nanoparticles for Cell Labeling.

    Science.gov (United States)

    Wang, Xiaohui; Peng, Hongshang; Huang, Shihua; You, Fangtian

    2016-04-01

    In this paper, we report a series of fluorescent biocompatible nanoparticles (NPs), prepared by a facile reprecipitation-encapsulation method, for cellular labeling. The as-prepared NPs exhibit a narrow size distribution of 70-110 nm, and a core-shell structure comprised of a hybrid core doped with different dyes and a poly-L-lysine (PLL) shell. With coumarin 6, nile red, and meso- tetraphenylporphyrin as the imaging agents, the fluorescent NPs gave green, orange, and red emissions respectively. Due to the positively charged PLL shell, the fluorescent NPs exhibit neglected cytotoxicity and efficient cellular uptake. After incubation with living cells, the results obtained by laser confocal microscope from green, orange, and red channels all clearly show that the fluores- cent NPs are inhomogenously localized inside the cytoplasm without penetrating into the nucleus. Since such PLL-modified NPs can encapsulate other hydrophobic dyes, a wide spectrum of nanoimaging agents is thus expected. Furthermore, the surface amino groups on the PLL shell afford an anchoring site for further bioconjugation, and targeted imaging is also very promising. PMID:27451673

  8. Biocompatible and colloidally stabilized mPEG-PE/calcium phosphate hybrid nanoparticles loaded with siRNAs targeting tumors.

    Science.gov (United States)

    Gao, Pei; Zhang, Xiangyu; Wang, Hongzhi; Zhang, Qinghong; Li, He; Li, Yaogang; Duan, Yourong

    2016-01-19

    Calcium phosphate nanoparticles are safe and effective delivery vehicles for small interfering RNA (siRNA), as a result of their excellent biocompatibility. In this work, mPEG-PE (polyethylene glycol-L-α-phosphatidylethanolamine) was synthesized and used to prepare nanoparticles composed of mPEG-PE and calcium phosphate for siRNA delivery. Calcium phosphate and mPEG-PE formed the stable hybrid nanoparticles through self-assembly resulting from electrostatic interaction in water. The average size of the hybrid nanoparticles was approximately 53.2 nm with a negative charge of approximately -16.7 mV, which was confirmed by dynamic light scattering (DLS) measurements. The nanoparticles exhibited excellent stability in serum and could protect siRNA from ribonuclease (RNase) degradation. The cellular internalization of siRNA-loaded nanoparticles was evaluated in SMMC-7721 cells using a laser scanning confocal microscope (CLSM) and flow cytometry. The hybrid nanoparticles could efficiently deliver siRNA to cells compared with free siRNA. Moreover, the in vivo distribution of Cy5-siRNA-loaded hybrid nanoparticles was observed after being injected into tumor-bearing nude mice. The nanoparticles concentrated in the tumor regions through an enhanced permeability and retention (EPR) effect based on the fluorescence intensities of tissue distribution. A safety evaluation of the nanoparticles was performed both in vitro and in vivo demonstrating that the hybrid nanoparticle delivery system had almost no toxicity. These results indicated that the mPEG-PE/CaP hybrid nanoparticles could be a stable, safe and promising siRNA nanocarrier for anticancer therapy.

  9. Green chemistry approach for the synthesis and stabilization of biocompatible gold nanoparticles and their potential applications in cancer therapy

    Science.gov (United States)

    Mukherjee, Sudip; Sushma, V.; Patra, Sujata; Barui, Ayan Kumar; Pal Bhadra, Manika; Sreedhar, Bojja; Ranjan Patra, Chitta

    2012-11-01

    The biological approach to synthesis of AuNPs is eco-friendly and an ideal method to develop environmentally sustainable nanoparticles alternative to existing methods. We have developed a simple, fast, clean, efficient, low-cost and eco-friendly single-step green chemistry approach for the synthesis of biocompatible gold nanoparticles (AuNPs) from chloroauric acid (HAuCl4) using a water extract of Eclipta Alba leaves at room temperature. The AuNPs using Eclipta extract have been formed in very short time, even in less than 10 min. The as-synthesized AuNPs were thoroughly characterized by several physico-chemical techniques. The in vitro stability of as-synthesized AuNPs was studied in different buffer solutions. A plausible mechanism for the synthesis of AuNPs by Eclipta extract has been discussed. The biocompatibility of AuNPs was observed by in vitro cell culture assays. Finally, we have designed and developed a AuNPs-based drug delivery system (DDS) (Au-DOX) containing doxorubicin (DOX), a FDA approved anticancer drug. Administration of this DDS to breast cancer cells (MCF-7 and MDA-MB-231) shows significant inhibition of breast cancer cell proliferation compared to pristine doxorubicin. Therefore we strongly believe that the use of Eclipta Alba offers large-scale production of biocompatible AuNPs that can be used as a delivery vehicle for the treatment of cancer diseases.

  10. Synthesis of protein-coated biocompatible methotrexate-loaded PLA-PEG-PLA nanoparticles for breast cancer treatment

    Directory of Open Access Journals (Sweden)

    Salam Massadeh

    2016-06-01

    Full Text Available Background: PLA-PEG-PLA triblock polymer nanoparticles are promising tools for targeted dug delivery. The main aim in designing polymeric nanoparticles for drug delivery is achieving a controlled and targeted release of a specific drug at the therapeutically optimal rate and choosing a suitable preparation method to encapsulate the drug efficiently, which depends mainly on the nature of the drug (hydrophilic or hydrophobic. In this study, methotrexate (MTX-loaded nanoparticles were prepared by the double emulsion method. Method: Biodegradable polymer polyethylene glycol-polylactide acid tri-block was used with poly(vinyl alcohol as emulsifier. The resulting methotrexate polymer nanoparticles were coated with bovine serum albumin in order to improve their biocompatibility. This study focused on particle size distribution, zeta potential, encapsulation efficiency, loading capacity, and in vitro drug release at various concentrations of PVA (0.5%, 1%, 2%, and 3%. Results: Reduced particle size of methotrexate-loaded nanoparticles was obtained using lower PVA concentrations. Enhanced encapsulation efficiency and loading capacity was obtained using 1% PVA. FT-IR characterization was conducted for the void polymer nanoparticles and for drug-loaded nanoparticles with methotrexate, and the protein-coated nanoparticles in solid state showed the structure of the plain PEG-PLA and the drug-loaded nanoparticles with methotrexate. The methotrexate-loaded PLA-PEG-PLA nanoparticles have been studied in vitro; the drug release, drug loading, and yield are reported. Conclusion: The drug release profile was monitored over a period of 168 hours, and was free of burst effect before the protein coating. The results obtained from this work are promising; this work can be taken further to develop MTX based therapies.

  11. Chitosan-tripolyphosphate nanoparticles as Arrabidaea chica standardized extract carrier: synthesis, characterization, biocompatibility, and antiulcerogenic activity.

    Science.gov (United States)

    Servat-Medina, Leila; González-Gómez, Alvaro; Reyes-Ortega, Felisa; Sousa, Ilza Maria Oliveira; Queiroz, Nubia de Cássia Almeida; Zago, Patricia Maria Wiziack; Jorge, Michelle Pedrosa; Monteiro, Karin Maia; de Carvalho, João Ernesto; San Román, Julio; Foglio, Mary Ann

    2015-01-01

    Natural products using plants have received considerable attention because of their potential to treat various diseases. Arrabidaea chica (Humb. & Bonpl.) B. Verlot is a native tropical American vine with healing properties employed in folk medicine for wound healing, inflammation, and gastrointestinal colic. Applying nanotechnology to plant extracts has revealed an advantageous strategy for herbal drugs considering the numerous features that nanostructured systems offer, including solubility, bioavailability, and pharmacological activity enhancement. The present study reports the preparation and characterization of chitosan-sodium tripolyphosphate nanoparticles (NPs) charged with A. chica standardized extract (AcE). Particle size and zeta potential were measured using a Zetasizer Nano ZS. The NP morphological characteristics were observed using scanning electron microscopy. Our studies indicated that the chitosan/sodium tripolyphosphate mass ratio of 5 and volume ratio of 10 were found to be the best condition to achieve the lowest NP sizes, with an average hydrodynamic diameter of 150±13 nm and a zeta potential of +45±2 mV. Particle size decreased with AcE addition (60±10.2 nm), suggesting an interaction between the extract's composition and polymers. The NP biocompatibility was evaluated using human skin fibroblasts. AcE-NP demonstrated capability of maintaining cell viability at the lowest concentrations tested, stimulating cell proliferation at higher concentrations. Antiulcerogenic activity of AcE-NP was also evaluated with an acute gastric ulcer experimental model induced by ethanol and indomethacin. NPs loaded with A. chica extract reduced the ulcerative lesion index using lower doses compared with the free extract, suggesting that extract encapsulation in chitosan NPs allowed for a dose reduction for a gastroprotective effect. The AcE encapsulation offers an approach for further application of the A. chica extract that could be considered a potential

  12. Development of an upconverting chelate assay

    Science.gov (United States)

    Xiao, Xudong; Haushalter, Jeanne P.; Kotz, Kenneth T.; Faris, Gregory W.

    2005-04-01

    We report progress on performing a cell-based assay for the detection of EGFR on cell surfaces by using upconverting chelates. An upconversion microscope has been developed for performing assays and testing optical response. A431 cells are labeled with europium DOTA and imaged using this upconverting microscope.

  13. In-vitro and in-vivo imaging of prostate tumor using NaYF4: Yb, Er up-converting nanoparticles.

    Science.gov (United States)

    Yu, Yongjiang; Huang, Tao; Wu, Yu; Ma, Xiaorong; Yu, Guopeng; Qi, Jun

    2014-04-01

    The aim of this study was to investigate the feasibility of prostate tumor bioimaging both in vitro and in vivo using an upconversion fluorophore, NaYF4: Yb, Er nanoparticles. Luminescent signals of human prostate cancer cells (CWR22R and LNCaP) labeled with NaYF4: Yb, Er nanoparticles were detected by laser scanning confocal microscope, while Cy3 or FITC was used as control probe. Mouse-human prostate cancer model was developed by subcutaneously injecting the CWR22R cells into BALB/c nude mice to investigate the in-vivo imaging properties of NaYF4:Yb, Er nanoparticles. Both CWR22R and LNCaP cells could phagocytose NaYF4:Yb, Er nanoparticles in vitro, and the cellular uptake of CWR22R cells was much higher than that of LNCaP cells (95.42 ± 3.47 % vs. 51.63 ± 6.43 %), which made us choose the former for the further study. CWR22R cells pre-labeled with NaYF4:Yb, Er nanoparticles showed no obvious decrease of fluorescence intensity (P > 0.05) after light exposure, while the fluorescence intensity of Cy3 or FITC labeled cells decreased rapidly with prolonged bleaching (P nanoparticles formed tumors 4 weeks after injection, and the tumor length-diameter of the nanoparticle group and the control group was (10.3 ± 2.0) mm and (9.8 ± 2.5) mm, respectively. Significant upconversion fluorescence signals were observed in the tumors of the nanoparticle group when being excited at 980 nm by a NIR laser. In summary, the results suggest that as an intensive fluorescence imaging label agent, NaYF4:Yb, Er nanoparticles possess unique features and can be used for imaging prostate tumor cells both in vitro and in vivo by phagocytosis.

  14. Polyphosphoric acid capping radioactive/upconverting NaLuF4:Yb,Tm,153Sm nanoparticles for blood pool imaging in vivo.

    Science.gov (United States)

    Peng, Juanjuan; Sun, Yun; Zhao, Lingzhi; Wu, Yongquan; Feng, Wei; Gao, Yanhong; Li, Fuyou

    2013-12-01

    Nanoparticles that circulate in the bloodstream for a prolonged period of time have important biomedicine applications. However, no example of lanthanide-based nanoparticles having a long-term circulation bloodstream has been reported to date. Herein, we report on difunctional radioactive and upconversion nanoparticles (UCNP) coated with polyphosphoric acid ligand, that is ethylenediamine tetramethylenephosphonic acid (EDTMP), for an application in single-photon emission computed tomography (SPECT) blood pool imaging. The structure, size and zeta-potential of the EDTMP-coated nanoparticles (EDTMP-UCNP) are verified using transmission electron microscopy and dynamic light scattering. Injection of radioisotope samarium-153-labeled EDTMP-UCNP (EDTMP-UCNP:(153)Sm) into mice reveal superior circulation time compared to control nanoparticles coated with citric acid (cit-UCNP:(153)Sm) and (153)Sm complex of EDTMP (EDTMP-(153)Sm). The mechanism for the extended circulation time may be attributed to the adhesion of EDTMP-UCNP on the membrane of red blood cells (RBCs). In vivo toxicity results show no toxicity of EDTMP-UCNP at the dose of 100 mg/kg, validating its safety as an agent for blood pool imaging. Our results provide a new strategy of nanoprobe for a long-term circulation bloodstream by introducing polyphosphoric acid as surface ligand.

  15. Enhanced Photovoltaic Performance of Dye-Sensitized Solar Cells by Efficient Near-Infrared Sunlight Harvesting using Upconverting Y2O 3:Er (3+)/Yb (3+) Phosphor Nanoparticles.

    Science.gov (United States)

    Du, Peng; Lim, Joo Ho; Leem, Jung Woo; Cha, Sung Min; Yu, Jae Su

    2015-12-01

    We report the efficiency enhancement in dye-sensitized solar cells (DSSCs) using Er(3+)/Yb(3+)-co-doped Y2O3 (i.e., Y2O3:Er(3+)/Yb(3+)) phosphor nanoparticles, prepared by a simple and cost-effective urea-based homogeneous precipitation method, for efficient near-infrared (NIR) sunlight harvesting. Under the light excitation at a wavelength of 980 nm, the as-prepared samples exhibited strong upconversion emissions at green and red visible wavelengths. To investigate the influence of Y2O3:Er(3+)/Yb(3+) nanoparticles on the photovoltaic performance of DSSCs, the phosphor nanoparticles were incorporated into titanium dioxide films to form a composite photoelectrode. For the resulting DSSCs, the increased power conversion efficiency (PCE) of 6.68 % was obtained mainly by the increased photocurrent of J SC = 13.68 mA/cm(2) due to the light harvesting enhancement via the NIR-to-visible upconversion process (cf., PCE = 5.94 %, J SC = 12.74 mA/cm(2) for the reference DSSCs without phosphor nanoparticles), thus, indicating the PCE increment ratio of ~12.4 %.

  16. Argpyrimidine-tagged rutin-encapsulated biocompatible (ethylene glycol dimers) nanoparticles: Synthesis, characterization and evaluation for targeted drug delivery.

    Science.gov (United States)

    Bhattacherjee, Abhishek; Dhara, Kaliprasanna; Chakraborti, Abhay Sankar

    2016-07-25

    Diabetes mellitus represents a major metabolic disorder affecting millions of people all over the world. Currently available therapeutic treatments are not good enough to control the long-term complications of diabetes. Active targeting via inclusion of a specific ligand on the nanoparticles provides effective therapeutic approach in different diseases. However, such specific drug delivery systems have not been explored much in diabetes due to lack of suitable biological targets in this disorder. Our objective is to synthesize a ligand-tagged drug-loaded nanoparticle for delivery of the drug at specific sites to enhance its therapeutic efficiency in diabetic condition. The nanoparticles have been prepared by using biocompatible ethylene glycol-bis (succinic acid N-hydroxysuccinimide ester) dimers. Although advanced glycation end products (AGEs) are the root causes of diabetic complications, argpyrimidine, an AGE, possesses antioxidant and reducing activities. AGE interacts selectively with its cell surface receptors (RAGE), which are significantly increased in diabetic condition. We have selected RAGE as the target of argpyrimidine, which is tagged on the nanoparticles as a ligand. Rutin, having anti-hyperglycemic and anti-glycating activities, has been used for nanoencapsulation. Rutin-loaded argpyrimidine-tagged nanoparticles have been synthesized and characterized. We have demonstrated the drug releasing capacity and target specificity of the synthesised drug delivery system under ex vivo and in vivo conditions. PMID:27234699

  17. A new methodology for studying nanoparticle interactions in biological systems: Dispersing titania in biocompatible media using chemical stabilisers

    Science.gov (United States)

    Ramirez-Garcia, Sonia; Chen, Lan; Morris, Michael A.; Dawson, Kenneth A.

    2011-11-01

    We report here a highly successful and original protocol for the dispersion of nanoparticles in biocompatible fluids for in vitro and in vivo studies of the nanoparticle-biology interaction. Titania is chosen as a suitable model as it is one of the priority materials listed by the OECD and small particles of the anatase structure are extensively used as e.g. photocatalysts in solar cells. Consequently, its delivery into the environment and its interaction with biological organisms is unavoidable. Therefore, its biological effect needs to be understood. In this work, we prepared stable nanoparticle dispersions of anatase aggregates using citrate stabilisations between 45 and 55 nm at concentrations of up to 10 mg mL-1. The optimum pH for this type of suspension was 7, resulting in ζ-potentials of approximately -50 mV. The stabilised aggregates were the subject of dialysis to produce stable dispersions without the chemical stabiliser, thus allowing studies in the absence of potentially toxic chemicals. Different sizing techniques such as Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA) and Differential Centrifuge Sedimentation (DCS) were used to characterise the different suspensions. The results obtained with each of these techniques are compared and a critical analysis of the suitability of each technique is given.We report here a highly successful and original protocol for the dispersion of nanoparticles in biocompatible fluids for in vitro and in vivo studies of the nanoparticle-biology interaction. Titania is chosen as a suitable model as it is one of the priority materials listed by the OECD and small particles of the anatase structure are extensively used as e.g. photocatalysts in solar cells. Consequently, its delivery into the environment and its interaction with biological organisms is unavoidable. Therefore, its biological effect needs to be understood. In this work, we prepared stable nanoparticle dispersions of anatase aggregates

  18. Design of Au/SPIO composite nanoparticle for facile and biocompatible surface functionalization via Au-S bond

    Energy Technology Data Exchange (ETDEWEB)

    Seino, Satoshi, E-mail: seino@mit.eng.osaka-u.ac.jp; Shibata, Yujin; Yamanaka, Masayuki; Nakagawa, Takashi [Osaka University, Graduate School of Engineering (Japan); Mukai, Yohei; Nakagawa, Shinsaku [Osaka University, Graduate School of Pharmaceutical Sciences and Center for Advanced Medical Engineering and Informatics (Japan); Yamamoto, Takao A. [Osaka University, Graduate School of Engineering (Japan)

    2013-01-15

    Immobilization of Au nanoparticles on super-paramagnetic iron-oxide (SPIO) enables facile and biocompatible surface functionalization via Au-S bond. Au/SPIO composite nanoparticle is easily modified by thiol-modified polyethylene glycol (PEG-SH), and they are successfully applied on MR tumor imaging. However, its large hydrodynamic size ({approx}150 nm) still causes the accumulation to liver in vivo. In this study, we controlled the hydrodynamic size of Au/SPIO by testing different raw SPIOs and stabilizing polymers. As the best candidate, Au/Molday-ION which was synthesized from Molday-ION and polyvinyl alcohol comprised the hydrodynamic size of 56 nm. Moreover, PEGylated Au/Molday-ION showed excellent dispersibility in blood serum, with the hydrodynamic size of 65 nm. This surface functionalization strategy is effective for the constructions of magnetic nanocarriers for in vivo applications.

  19. Enhanced bio-compatibility of ferrofluids of self-assembled superparamagnetic iron oxide-silica core-shell nanoparticles.

    Science.gov (United States)

    Narayanan, T N; Mary, A P Reena; Swalih, P K Anas; Kumar, D Sakthi; Makarov, D; Albrecht, M; Puthumana, Jayesh; Anas, Abdulaziz; Anantharaman, M R

    2011-03-01

    Self-assembled magnetic colloidal suspensions are sought after by material scientists owing to its huge application potential. The biomedical applications of colloidal nanoparticles necessitate that they are biocompatible, non-interacting, monodispersed and hence the synthesis of such nanostructures has great relevance in the realm of nanoscience. Silica-coated superparamagnetic iron oxide nanoparticles based ferrofluids were prepared using polyethylene glycol as carrier fluid by employing a controlled co-precipitation technique followed by a modified sol-gel synthesis. A plausible mechanism for the formation of stable suspension of SiO2-coated Iron Oxide nanoparticles with a size of about 9 nm dispersed in polyethylene glycol (PEG) is proposed. Core-shell nature of the resultant SiO2-Iron Oxide nanocomposite was verified using transmission electron microscopy. Fourier transform-infrared spectroscopy studies were carried out to understand the structure and nature of chemical bonds. The result suggests that Iron Oxide exist in an isolated state inside silica matrix. Moreover, the presence of silanol bonds establishes the hydrophilic nature of silica shell confirming the formation of stable ferrofluid with PEG as carrier fluid. The magnetic characterization reveals the superparamagnetic behavior of the nanoparticles with a rather narrow distribution of blocking temperatures. These properties are not seen in ferrofluids prepared from Iron Oxide nanoparticles without SiO2 coating. The latter suggests the successful tuning of the inter-particle interactions preventing agglomeration of nanoparticles. Cytotoxicity studies on citric acid coated water based ferrofluid and silica-coated PEG-based ferrofluid were evaluated by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium chloride assay and it shows an enhanced compatibility for silica modified nanoparticles. PMID:21449334

  20. Iron oxide nanoparticles surface coating and cell uptake affect biocompatibility and inflammatory responses of endothelial cells and macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Orlando, Antonina [University of Milano-Bicocca, Department of Health Sciences (Italy); Colombo, Miriam; Prosperi, Davide [University of Milano-Bicocca, Department of Biotechnology and Biosciences (Italy); Gregori, Maria; Panariti, Alice; Rivolta, Ilaria; Masserini, Massimo; Cazzaniga, Emanuela, E-mail: emanuela.cazzaniga@unimib.it [University of Milano-Bicocca, Department of Health Sciences (Italy)

    2015-09-15

    Engineered iron oxide nanoparticles (IONP) offer the possibility of a wide range of medical uses, from clinical imaging to magnetically based hyperthermia for tumor treatment. These applications require their systemic administration in vivo. An important property of nanoparticles is their stability in biological media. For this purpose, a multicomponent nanoconstruct combining high colloidal stability and improved physical properties was synthesized and characterized. IONP were coated with an amphiphilic polymer (PMA), which confers colloidal stability, and were pegylated in order to obtain the nanoconstruct PEG-IONP-PMA. The aim of this study was to utilize cultured human endothelial cells (HUVEC) and murine macrophages, taken as model of cells exposed to NP after systemic administration, to assess the biocompatibility of PEG-IONP-PMA (23.1 ± 1.4 nm) or IONP-PMA (15.6 ± 3.4 nm). PEG-IONP-PMA, tested at different concentrations as high as 20 μg mL{sup −1}, exhibited no cytotoxicity or inflammatory responses. By contrast, IONP-PMA showed a concentration-dependent increase of cytotoxicity and of TNF-α production by macrophages and NO production by HUVECs. Cell uptake analysis suggested that after PEGylation, IONP were less internalized either by macrophages or by HUVEC. These results suggest that the choice of the polymer and the chemistry of surface functionalization are a crucial feature to confer to IONP biocompatibility.

  1. Preparation and in vitro evaluation of doxorubicin-loaded Fe3O4 magnetic nanoparticles modified with biocompatible copolymers

    Directory of Open Access Journals (Sweden)

    Akbarzadeh A

    2012-02-01

    modified with PLGA:PEG2000, PLGA:PEG3000, and PLGA:PEG4000 copolymers was 69.5%, 73%, and 78%, respectively, and the release kinetics were controlled. The in vitro cytotoxicity test showed that the Fe3O4-PLGA:PEG4000 magnetic nanoparticles had no cytotoxicity and were biocompatible.Conclusion: There is potential for use of these nanoparticles for biomedical application. Future work includes in vivo investigation of the targeting capability and effectiveness of these nanoparticles in the treatment of lung cancer.Keywords: superparamagnetic iron oxide nanoparticles, triblock copolymer, doxorubicin encapsulation, water uptake, drug encapsulation efficiency

  2. Egg white-mediated green synthesis of silver nanoparticles with excellent biocompatibility and enhanced radiation effects on cancer cells

    Directory of Open Access Journals (Sweden)

    Lu RQ

    2012-04-01

    Full Text Available Renquan Lu1, Dapeng Yang2, Daxiang Cui2, Zhongyang Wang3, Lin Guo11Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, Shanghai, 2Department of Bio-Nano-Science and Engineering, National Key Laboratory of Nano/Micro Fabrication Technology, Key Laboratory for Thin Film and Microfabrication of Ministry of Education, Institute of Micro-Nano Science and Technology, Shanghai Jiao Tong University, Shanghai, 3College of Chemistry and Chemical Engineering, Yantai University, Shan Dong Province, People's Republic of ChinaAbstract: A simple, cost-effective, and environmentally friendly approach to the aqueous-phase synthesis of silver (Ag nanoparticles was demonstrated using silver nitrate (AgNO3 and freshly extracted egg white. The bio-conjugates were characterized by UV-visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and dynamic light scattering. These results indicated that biomolecule-coated Ag nanoparticles are predominantly spherical in shape with an average size of 20 nm. The proteins of egg white, which have different functional groups, played important roles in reducing Ag+ and maintaining product attributes such as stability and dispersity. In vitro cytotoxicity assays showed that these Ag-protein bio-conjugates showed good biocompatibility with mouse fibroblast cell lines 3T3. Furthermore, X-ray irradiation tests on 231 tumor cells suggested that the biocompatible Ag-protein bio-conjugates enhanced the efficacy of irradiation, and thus may be promising candidates for use during cancer radiation therapy.Keywords: green chemistry, biosynthesis, egg white, Ag nanoparticles, X-ray irradiation

  3. Antibacterial and anticancerous biocompatible silver nanoparticles synthesised from the cold-tolerant strain of Spirulina platensis

    Directory of Open Access Journals (Sweden)

    Selvaraj Karthick Raja Namasivayam

    2015-04-01

    Full Text Available Objective: To synthesize silver nanoparticles from the biomass of cold tolerant strain of Spirulina platensis and evalute the synthesized nanoparticles against antibacterial and anticancer activity. Methods: Silver nanoparticles were synthesized by the algal culture and characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy and X ray diffraction studies. Antibacterial activity has been studied with free nanoparticles adopting agar diffusion assay, biofilm inhibition assay and nanoparticles fabricated wound dressing against representative Gram-negative organism Pseudomonas aeruginosa and Gram-positive organism Staphylococcus aureus respectively. The in vitro anticancer activity of silver nanoparticles were screened against human Hep2 cell lines by means of MTT assay. Results: Reduction of silver ions by the algal culture was observed during 72 h of incubation and the synthesized nanoparticles were further characterized. Antibacterial study reveals both the strains were susceptible to free nanoparticles and fabricated wound dressing treatment. The in vitro anticancer activity of silver nanoparticles were screened against human Hep 2 cell lines by means of MTT assay which reveals that cell viability has been reduced as dose dependent manner. Conclusions: The observed results imply that silver nanoparticles synthesized from Spirulina platensis cold tolerant strain can be used as potential antibacterial and anticancerous agent.

  4. Antibacterial and anticancerous biocompatible silver nanoparticles synthesised from the cold-tolerant strain of Spirulina platensis

    Institute of Scientific and Technical Information of China (English)

    Duraisamy Jayakumar; Ramesh Kumar; Rajan SowriArvind Bharani

    2015-01-01

    Objective: To synthesize silver nanoparticles from the biomass of cold tolerant strain of Spirulina platensis and evalute the synthesized nanoparticles against antibacterial and anticancer activity. Methods: Silver nanoparticles were synthesized by the algal culture and characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy and X ray diffraction studies. Antibacterial activity has been studied with free nanoparticles adopting agar diffusion assay, biofilm inhibition assay and nanoparticles fabricated wound dressing against representative Gram-negative organism Pseudomonas aeruginosa and Gram-positive organism Staphylococcus aureus respectively. The in vitro anticancer activity of silver nanoparticles were screened against human Hep2 cell lines by means of MTT assay. Results: Reduction of silver ions by the algal culture was observed during 72 h of incubation and the synthesized nanoparticles were further characterized. Antibacterial study reveals both the strains were susceptible to free nanoparticles and fabricated wound dressing treatment. The in vitro anticancer activity of silver nanoparticles were screened against human Hep 2 cell lines by means of MTT assay which reveals that cell viability has been reduced as dose dependent manner. Conclusions: The observed results imply that silver nanoparticles synthesized from Spirulina platensis cold tolerant strain can be used as potential antibacterial and anticancerous agent.

  5. Biocompatibility of cerium dioxide and silicon dioxide nanoparticles with endothelial cells

    Directory of Open Access Journals (Sweden)

    Claudia Strobel

    2014-10-01

    Full Text Available Cerium dioxide (CeO2 and silicon dioxide (SiO2 nanoparticles are of widespread use in modern life. This means that human beings are markedly exposed to them in their everyday life. Once passing biological barriers, these nanoparticles are expected to interact with endothelial cells, leading to systemic alterations with distinct influences on human health. In the present study we observed the metabolic impact of differently sized CeO2 (8 nm; 35 nm and SiO2 nanoparticles (117 nm; 315 nm on immortalized human microvascular (HMEC-1 and primary macrovascular endothelial cells (HUVEC, with particular focus on the CeO2 nanoparticles. The characterization of the CeO2 nanoparticles in cell culture media with varying serum content indicated a steric stabilization of nanoparticles due to interaction with proteins. After cellular uptake, the CeO2 nanoparticles were localized around the nucleus in a ring-shaped manner. The nanoparticles revealed concentration and time, but no size-dependent effects on the cellular adenosine triphosphate levels. HUVEC reacted more sensitively to CeO2 nanoparticle exposure than HMEC-1. This effect was also observed in relation to cytokine release after nanoparticle treatment. The CeO2 nanoparticles exhibited a specific impact on the release of diverse proteins. Namely, a slight trend towards pro-inflammatory effects, a slight pro-thrombotic impact, and an increase of reactive oxygen species after nanoparticle exposure were observed with increasing incubation time. For SiO2 nanoparticles, concentration- and time-dependent effects on the metabolic activity as well as pro-inflammatory reactions were detectable. In general, the effects of the investigated nanoparticles on endothelial cells were rather insignificant, since the alterations on the metabolic cell activity became visible at a nanoparticle concentration that is by far higher than those expected to occur in the in vivo situation (CeO2 nanoparticles: 100 µg/mL; SiO2

  6. Green synthesis of biocompatible gold nanoparticles using Fagopyrum esculentum leaf extract

    Science.gov (United States)

    Babu, Punuri Jayasekhar; Sharma, Pragya; Kalita, Mohan Chandra; Bora, Utpal

    2011-12-01

    This report describes the use of ethnolic extract of Fagopyrum esculentum leaves for the synthesis of gold nanoparticles. UV-visible spectroscopy analysis indicated the successful formation of gold nanoparticles. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM), high resolution TEM (HRTEM) and were found to be spherical, hexagonal and triangular in shape with an average size of 8.3 nm. The crystalline nature of the gold nanoparticles was confirmed from X-ray diffraction (XRD) and selected-area electron diffraction (SAED) patterns. Fourier transform infrared (FT-IR) and energy-dispersive X-ray analysis (EDX) suggested the presence of organic biomolecules on the surface of the gold nanoparticles. Cytotoxicity tests against human HeLa, MCF-7 and IMR-32 cancer cell lines revealed that the gold nanoparticles were non-toxic and thus have potential for use in various biomedical applications.

  7. Laser-induced breakdown spectroscopy of γ-Fe 2O 3 nanoparticles in a biocompatible alginate matrix

    Science.gov (United States)

    Brown, E.; Rehse, S. J.

    2007-12-01

    An intensive multi-disciplinary research effort is underway at Wayne State University to synthesize and characterize magnetic nanoparticles in a biocompatible matrix for biomedical applications. The particular system being studied consists of 3-10 nm γ-Fe 2O 3 nanoparticles in an alginate matrix, which is being studied for applications in targeted drug delivery, as a magnetic-resonance imaging (MRI) contrast agent, and for hyperthermic treatments of malignant tumors. In the present work we report on our efforts to determine if laser-induced breakdown spectroscopy (LIBS) can offer a more accurate and substantially faster determination of iron content in such nanoparticle-containing materials than competing technologies such as inductively-coupled plasma (ICP). Standardized samples of α-Fe 2O 3 nanoparticles (5-25 nm diameter) and silver micropowder (2-3.5 μm diameter) were created with thirteen precisely known concentrations and pressed hydraulically to create solid "pellets" for LIBS analysis. The ratio of the intensity of an Fe(I) emission line at 371.994 nm to that of an Ag(I) line at 328.069 nm was used to create a calibration curve exhibiting an exponential dependence on Fe mass fraction. Using this curve, an "unknown" γ-Fe 2O 3/alginate/silver pellet was tested, leading to a measurement of the mass fraction of Fe in the nanoparticle/alginate matrix of 51 ± 3 wt.%, which is in very good agreement with expectations and previous determinations of its iron concentration.

  8. Water-soluble and biocompatible MnO@PVP nanoparticles for MR imaging in vitro and in vivo.

    Science.gov (United States)

    Hu, Xiaoqing; Ji, Yuxuan; Wang, Mingliang; Miao, Fei; Ma, Hongmei; Shen, Hebai; Jia, Nengqin

    2013-06-01

    The uniform-sized manganese oxide nanoparticles (the oleic-capped MnO NPs) were synthesized by the thermal decomposition of Mn-oleate complex and were transferred into water with the help of cationic surfactant of cetyltrimethyl ammonium bromide (CTAB), then the poly(vinylpyrrolidone) (PVP) membrane was further coated on to them with the aid of anionic dispersant of poly(styrenesulfonate) (PSS) by layer-by-layer electrostatic assembly to render them water soluble and biocompatible. They were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and MTT assay. In vitro cellular uptake test revealed the MnO@PVP NPs were low cytotoxic, biocompatible and could be used as a T,-positive contrast agent for passive targeting magnetic resonance imaging (MRI). Interestingly, signal enhancement in cerebral spinal fluid (CSF) spaces in vivo experiment suggested that the MnO@PVP NPs can pass through the blood brain barrier (BBB). These results show that MnO@PVP NPs are good candidates as MRI contrast agents with the lack of cytotoxicity and have great potential applications in magnetic nano-device and biomagnetic field. PMID:23858961

  9. One-pot green synthesis of biocompatible arginine-stabilized magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhongjun; Zhu Hui; Wang Xiaolei; Yang Fan; Yang Xiurong, E-mail: xryang@ciac.jl.c [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022 (China)

    2009-11-18

    A green one-step approach has been developed for the synthesis of amino-functionalized magnetite nanoparticles. The synthesis was accomplished by simply mixing FeCl{sub 2} with arginine under ambient conditions. It was found that the Fe{sup 2+}/arginine molar ratio, reaction duration and temperature greatly influence the size, morphology and composition of magnetic nanoparticles. The arginine-stabilized magnetic nanoparticles were characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy techniques. The results show that the prepared nanoparticles are spherically shaped with a nearly uniform size distribution and pure magnetite phase. The presence of arginine on the magnetic nanoparticle surface has been confirmed and the amount of surface arginine varies with the Fe{sup 2+}/arginine molar ratio. The surface amine densities are calculated to be 5.60 and 7.84 {mu}mol mg{sup -1} for magnetic nanoparticles prepared at 1:1 and 1:2 Fe{sup 2+}/arginine molar ratio, respectively. The as-synthesized nanoparticles show superparamagnetic behavior at room temperature and good solubility in water. In addition, using a similar synthesis procedure, we have been able to synthesize superparamagnetic manganese and cobalt ferrite nanoparticles.

  10. One-pot green synthesis of biocompatible arginine-stabilized magnetic nanoparticles

    International Nuclear Information System (INIS)

    A green one-step approach has been developed for the synthesis of amino-functionalized magnetite nanoparticles. The synthesis was accomplished by simply mixing FeCl2 with arginine under ambient conditions. It was found that the Fe2+/arginine molar ratio, reaction duration and temperature greatly influence the size, morphology and composition of magnetic nanoparticles. The arginine-stabilized magnetic nanoparticles were characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy techniques. The results show that the prepared nanoparticles are spherically shaped with a nearly uniform size distribution and pure magnetite phase. The presence of arginine on the magnetic nanoparticle surface has been confirmed and the amount of surface arginine varies with the Fe2+/arginine molar ratio. The surface amine densities are calculated to be 5.60 and 7.84 μmol mg-1 for magnetic nanoparticles prepared at 1:1 and 1:2 Fe2+/arginine molar ratio, respectively. The as-synthesized nanoparticles show superparamagnetic behavior at room temperature and good solubility in water. In addition, using a similar synthesis procedure, we have been able to synthesize superparamagnetic manganese and cobalt ferrite nanoparticles.

  11. Caveolae-mediated endocytosis of biocompatible gold nanoparticles in living Hela cells

    DEFF Research Database (Denmark)

    Hao, Xian; Wu, Jiazhen; Shan, Yuping;

    2012-01-01

    Efficient intracellular delivery of gold nanoparticles (AuNPs) and unraveling the mechanism underlying the intracellular delivery are essential for advancing the applications of AuNPs toward in vivo imaging and therapeutic interventions. We employed fluorescence microscopy to investigate...... the intracellular delivery of small-size nanoparticles for biomedical applications....

  12. Effect of surface coating on the biocompatibility and in vivo MRI detection of iron oxide nanoparticles after intrapulmonary administration.

    Science.gov (United States)

    Al Faraj, Achraf; Shaik, Abjal Pasha; Shaik, Asma Sultana

    2015-01-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) have attracted special attention as novel nanoprobes capable of improving both the therapy and diagnosis of lung diseases. For safe prospective clinical applications, their biocompatibility has to be assessed after intrapulmonary administration. This study was therefore conducted to understand the biological impact of SPIONs and their further surface-functionalization with polyethylene glycol (PEG) having either negative (i.e. carboxyl) or positive (i.e. amine) terminal in a 1-month longitudinal study following acute and sub-acute exposures. Noninvasive free-breathing MR imaging protocols were first optimized to validate SPIONs detection in the lung and investigate possible subsequent systemic translocation to abdominal organs. Pulmonary Magnetic Resonance Imaging (MRI) allowed successful in vivo detection of SPIONs in the lung using ultra-short echo time sequence. Following high-dose lung administration, MR imaging performed on abdominal organs detected transient accumulation of SPIONs in the liver. Iron quantification using Inductive coupled plasma - Mass mass spectroscopy (ICP-MS) confirmed MRI readouts. Oxidative stress induction and genotoxicity were then conducted to evaluate the biocompatibility of SPIONs with their different formulations in a mouse model. A significant increase in lipid peroxidation was observed in both acute and sub-acute sets and found to regress in a time-dependent manner. PEG functionalized SPIONs revealed a lower effect with no difference between both terminal modifications. Genotoxicity assessments revealed an increase in DNA damage and gene expression of CCL-17 and IL-10 biomarkers following SPIONs administration, which was significantly higher than surface-modified nanoparticles and decreased in a time-dependent manner. However, SPIONs with carboxyl terminal showed a slightly prominent effect compared to amine modification. PMID:26356541

  13. Biocompatibility of chitosan-coated iron oxide nanoparticles with osteoblast cells

    Directory of Open Access Journals (Sweden)

    Shi S

    2012-10-01

    Full Text Available Si-Feng Shi,1 Jing-Fu Jia,2 Xiao-Kui Guo,3 Ya-Ping Zhao,2 De-Sheng Chen,1 Yong-Yuan Guo,1 Tao Cheng,1 Xian-Long Zhang11Department of Orthopedic Surgery, Shanghai Sixth People’s Hospital, School of Medicine, 2School of Chemistry and Chemical Technology, 3Department of Medical Microbiology and Parasitology, School of Medicine, Shanghai Jiao Tong University Shanghai, ChinaBackground: Bone disorders (including osteoporosis, loosening of a prosthesis, and bone infections are of great concern to the medical community and are difficult to cure. Therapies are available to treat such diseases, but all have drawbacks and are not specifically targeted to the site of disease. Chitosan is widely used in the biomedical community, including for orthopedic applications. The aim of the present study was to coat chitosan onto iron oxide nanoparticles and to determine its effect on the proliferation and differentiation of osteoblasts.Methods: Nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, x-ray diffraction, zeta potential, and vibrating sample magnetometry. Uptake of nanoparticles by osteoblasts was studied by transmission electron microscopy and Prussian blue staining. Viability and proliferation of osteoblasts were measured in the presence of uncoated iron oxide magnetic nanoparticles or those coated with chitosan. Lactate dehydrogenase, alkaline phosphatase, total protein synthesis, and extracellular calcium deposition was studied in the presence of the nanoparticles.Results: Chitosan-coated iron oxide nanoparticles enhanced osteoblast proliferation, decreased cell membrane damage, and promoted cell differentiation, as indicated by an increase in alkaline phosphatase and extracellular calcium deposition. Chitosan-coated iron oxide nanoparticles showed good compatibility with osteoblasts.Conclusion: Further research is necessary to optimize magnetic nanoparticles for the treatment of bone disease

  14. Monodispersed biocompatible Ag2S nanoparticles: Facile extracellular bio-fabrication using the gamma-proteobacterium, S. oneidensis

    Energy Technology Data Exchange (ETDEWEB)

    Suresh, Anil K [ORNL; Doktycz, Mitchel John [ORNL; Wang, Wei [ORNL; Moon, Ji Won [ORNL; Gu, Baohua [ORNL; Meyer III, Harry M [ORNL; Hensley, Dale K [ORNL; Retterer, Scott T [ORNL; Allison, David P [ORNL; Phelps, Tommy Joe [ORNL; Pelletier, Dale A [ORNL

    2011-01-01

    Interest in engineered metal and semiconductor nanocrystallites continues to grow due to their unique size and or shape dependent optoelectronic, physicochemical and biological properties. Therefore identifying novel non-hazardous nanoparticle synthesis routes that address hydrophilicity, size and shape control and production costs have become a priority. In the present illustration we report for the first time the efficient generation of extracellular Ag2S nanoparticles by the metal reducing bacterium, Shewanella oneidensis. The particles are nearly monodispersed with homogeneous shape distributions and are produced under ambient temperatures and pressures at high yield, 85 % theoretical maximum. UV-vis and Fourier transform infrared spectroscopy, dynamic light scattering, X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy measurements confirmed the formation, optical properties, purity, and crystallinity of the as-synthesized particles. Further characterization revealed that the particles consist of spheres in the size range of 1-22 nm, with an average size of 9 3 nm and are capped by a detachable protein/peptide surface coat. Toxicity assessments of these silver sulfide nanoparticles on Gram-negative Escherichia coli and Shewanella oneidensis and Gram-positive Bacillus subtilis bacterial systems as well as eukaryotic; mouse lung epithelial (C 10) and macrophage (RAW-264.7) cells showed that the particles were non-inhibitory or non-cytotoxic to both these systems. Our results provide a facile, eco-friendly and economical route for the fabrication of technologically important semiconducting Ag2S nanoparticles which are dispersible and biocompatible; thus providing excellent potential for their uses in optical imaging and electronic devices, and solar cell applications.

  15. Biologically Inspired Design of Biocompatible Iron Oxide Nanoparticles for Biomedical Applications

    OpenAIRE

    Demirer, Gözde S.; Okur, Aysu C; Kızılel, Seda

    2015-01-01

    During the last couple of decades considerable research efforts have been directed towards the synthesis and coating of iron oxide nanoparticles (IONPs) for biomedical applications. To address the current limitations, recent studies have focused on the design of new generation nanoparticle systems whose internalization and targeting capabilities have been improved through surface modifications. This review covers the most recent challenges and advances in the development of IONPs with enhance...

  16. Structured superparamagnetic nanoparticles for high performance mediator of magnetic fluid hyperthermia: synthesis, colloidal stability and biocompatibility evaluation.

    Science.gov (United States)

    Thorat, N D; Otari, S V; Bohara, R A; Yadav, H M; Khot, V M; Salunkhe, A B; Phadatare, M R; Prasad, A I; Ningthoujam, R S; Pawar, S H

    2014-09-01

    Core-shell structures with magnetic core and metal/polymer shell provide a new opportunity for constructing highly efficient mediator for magnetic fluid hyperthermia. Herein, a facile method is described for the synthesis of superparamagnetic LSMO@Pluronic F127 core-shell nanoparticles. Initially, the surface of the LSMO nanoparticles is functionalized with oleic acid and the polymeric shell formation is achieved through hydrophobic interactions with oleic acid. Each step is optimized to get good dispersion and less aggregation. This methodology results into core-shell formation, of average diameter less than 40 nm, which was stable under physiological conditions. After making a core-shell formulation, a significant increase of specific absorption rate (up to 300%) has been achieved with variation of the magnetization (Fe3O4. MTT assay is used to evaluate the toxicity of bare and core-shell MNPs. The mechanism of cell death by necrosis and apoptosis is studied with sequential staining of acridine orange and ethidium bromide using fluorescence and confocal microscopy. The present work reports a facile method for the synthesis of core-shell structure which significantly improves SAR and biocompatibility of bare LSMO MNPs, indicating potential application for hyperthermia. PMID:25063164

  17. Biomimetic synthesis of highly biocompatible gold nanoparticles with amino acid-dithiocarbamate as a precursor for SERS imaging

    Science.gov (United States)

    Li, Li; Liu, Jianbo; Yang, Xiaohai; Huang, Jin; He, Dinggeng; Guo, Xi; Wan, Lan; He, Xiaoxiao; Wang, Kemin

    2016-03-01

    Amino acid-dithiocarbamate (amino acid-DTC) was developed as both the reductant and ligand stabilizer for biomimetic synthesis of gold nanoparticles (AuNPs), which served as an excellent surface-enhanced Raman scattering (SERS) contrast nanoprobe for cell imaging. Glycine (Gly), glutamic acid (Glu), and histidine (His) with different isoelectric points were chosen as representative amino acid candidates to synthesize corresponding amino acid-DTC compounds through mixing with carbon disulfide (CS2), respectively. The pyrogenic decomposition of amino acid-DTC initiated the reduction synthesis of AuNPs, and the strong coordinating dithiocarbamate group of amino acid-DTC served as a stabilizer that grafted onto the surface of the AuNPs, which rendered the as-prepared nanoparticles a negative surface charge and high colloidal stability. MTT cell viability assay demonstrated that the biomimetic AuNPs possessed neglectful toxicity to the human hepatoma cell, which guaranteed them good biocompatibility for biomedical application. Meanwhile, the biomimetic AuNPs showed a strong SERS effect with an enhancement factor of 9.8 × 105 for the sensing of Rhodamine 6G, and two distinct Raman peaks located at 1363 and 1509 cm-1 could be clearly observed in the cell-imaging experiments. Therefore, biomimetic AuNPs can be explored as an excellent SERS contrast nanoprobe for biomedical imaging, and the amino acid-DTC mediated synthesis of the AuNPs has a great potential in bio-engineering and biomedical imaging applications.

  18. Synthesis, Surface Modification and Characterisation of Biocompatible Magnetic Iron Oxide Nanoparticles for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Mohamad Zaki Ab Rahman

    2013-06-01

    Full Text Available Superparamagnetic iron oxide nanoparticles (MNPs with appropriate surface chemistry exhibit many interesting properties that can be exploited in a variety of biomedical applications such as magnetic resonance imaging contrast enhancement, tissue repair, hyperthermia, drug delivery and in cell separation. These applications required that the MNPs such as iron oxide Fe3O4 magnetic nanoparticles (Fe3O4 MNPs having high magnetization values and particle size smaller than 100 nm. This paper reports the experimental detail for preparation of monodisperse oleic acid (OA-coated Fe3O4 MNPs by chemical co-precipitation method to determine the optimum pH, initial temperature and stirring speed in order to obtain the MNPs with small particle size and size distribution that is needed for biomedical applications. The obtained nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR, transmission electron microscopy (TEM, scanning electron microscopy (SEM, energy dispersive X-ray fluorescence spectrometry (EDXRF, thermogravimetric analysis (TGA, X-ray powder diffraction (XRD, and vibrating sample magnetometer (VSM. The results show that the particle size as well as the magnetization of the MNPs was very much dependent on pH, initial temperature of Fe2+ and Fe3+ solutions and steering speed. The monodisperse Fe3O4 MNPs coated with oleic acid with size of 7.8 ± 1.9 nm were successfully prepared at optimum pH 11, initial temperature of 45 °C and at stirring rate of 800 rpm. FTIR and XRD data reveal that the oleic acid molecules were adsorbed on the magnetic nanoparticles by chemisorption. Analyses of TEM show the oleic acid provided the Fe3O4 particles with better dispersibility. The synthesized Fe3O4 nanoparticles exhibited superparamagnetic behavior and the saturation magnetization of the Fe3O4 nanoparticles increased with the particle size.

  19. Biocompatible magnetite nanoparticles with varying silica-coating layer for use in biomedicine: physicochemical and magnetic properties, and cellular compatibility.

    Science.gov (United States)

    Singh, Rajendra K; Kim, Tae-Hyun; Patel, Kapil D; Knowles, Jonathan C; Kim, Hae-Won

    2012-07-01

    Magnetic nanoparticles (MNPs) are considered highly useful in therapeutic and diagnostic applications. However, MNPs require surface modification to promote dispersibility in aqueous solutions and thus biocompatibility. In this article, the authors modified MNPs with inorganic silica layer to create silica-coated magnetite nanoparticles (MNP@Si) via sol-gel process. Synthesis involves hydrolysis and condensation steps using tetraethylorthosilicate (TEOS) in methanol/ polyethylene glycol (PEG) solution and ammonia catalyst. Nanoparticles were characterized in terms of morphology, particle size, crystalline phase, chemical-bond structure, surface charge and magnetic properties: in particular, the MNP@Si size was easily tunable through alteration of the Fe(3) O(4) -to-TEOS ratio. As this ratio increased, the MNP@Si size decreased from 270 to 15 nm whilst maintaining core 12-nm MNP particle size, indicating decrease in thickness of the silica coating. All MNP@Si, in direct contrast to uncoated MNPs, showed excellent stability in aqueous solution. The particles' physicochemical and magnetic properties systematically varied with size (coating thickness), and the zeta potential diminished toward negative values, while magnetization increased as the coating thickness decreased. 15-nm MNP@Si showed excellent magnetization (about 64.1 emu/g), almost comparable to that of uncoated MNPs (70.8 emu/g). Preliminary in vitro assays confirmed that the silica layer significantly reduced cellular toxicity as assessed by increase in cell viability and reduction in reactive oxygen species production during 48 h of culture. Newly-developed MNP@Si, with a high capacity for magnetization, water-dispersibility, and diminished cell toxicity, may be potentially useful in diverse biomedical applications, including delivery of therapeutic and diagnostic biomolecules.

  20. Mass magnetophoretic experiment applied to the separation of biocompatible magnetic nanoparticles with potential for magnetohyperthermia

    International Nuclear Information System (INIS)

    A mass magnetophoretic experiment was developed to segregate nanoparticles according to their diameter and size dispersion. The samples were synthesized by the coprecipitation method and characterized using x-ray diffraction, high-resolution transmission electron microscopy and vibrating sample magnetometry. The mean diameter (standard deviation) showed a decrease of nanoparticle size (size dispersion) in the surface of the magnetic fluid sample submitted to the magnetophoretic experiment. Those effects were monitored by time-dependent apparent mass variation data, which could be important for scale-up applications. Magnetohyperthemia experiments were also performed, confirming our findings. (paper)

  1. The effect of laser repetition rate on the LASiS synthesis of biocompatible silver nanoparticles in aqueous starch solution

    Directory of Open Access Journals (Sweden)

    Zamiri R

    2013-01-01

    Full Text Available Reza Zamiri,1 Azmi Zakaria,1,* Hossein Abbastabar Ahangar,2 Majid Darroudi,3 Golnoosh Zamiri,1 Zahid Rizwan,1 Gregor PC Drummen4,* 1Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 2Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Selangor Darul Ehsan, Malaysia; 3Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 4Bionanoscience and Bio-Imaging Program, Cellular Stress and Ageing Program, Bio&Nano-Solutions, Düsseldorf, Germany*These authors contributed to this work equallyAbstract: Laser ablation-based nanoparticle synthesis in solution is rapidly becoming popular, particularly for potential biomedical and life science applications. This method promises one pot synthesis and concomitant bio-functionalization, is devoid of toxic chemicals, does not require complicated apparatus, can be combined with natural stabilizers, is directly biocompatible, and has high particle size uniformity. Size control and reduction is generally determined by the laser settings; that the size and size distribution scales with laser fluence is well described. Conversely, the effect of the laser repetition rate on the final nanoparticle product in laser ablation is less well-documented, especially in the presence of stabilizers. Here, the influence of the laser repetition rate during laser ablation synthesis of silver nanoparticles in the presence of starch as a stabilizer was investigated. The increment of the repetition rate does not negatively influence the ablation efficiency, but rather shows increased productivity, causes a red-shift in the plasmon resonance peak of the silver–starch nanoparticles, an increase in mean particle size and size distribution, and a distinct lack of agglomerate formation. Optimal results were achieved at 10 Hz repetition rate, with a mean particle size of ~10 nm and a

  2. Photocatalytic, Antimicrobial and Biocompatibility Features of Cotton Knit Coated with Fe-N-Doped Titanium Dioxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Miruna Silvia Stan

    2016-09-01

    Full Text Available Our research was focused on the evaluation of the photocatalytic and antimicrobial properties, as well as biocompatibility of cotton fabrics coated with fresh and reused dispersions of nanoscaled TiO2-1% Fe-N particles prepared by the hydrothermal method and post-annealed at 400 °C. The powders were characterized by X-ray diffraction (XRD, Mössbauer spectroscopy and X-ray photoelectron spectroscopy. The textiles coated with doped TiO2 were characterized by scanning electron microscopy and energy dispersive X-ray analyses, and their photocatalytic effect by trichromatic coordinates of the materials stained with methylene blue and coffee and exposed to UV, visible and solar light. The resulting doped TiO2 consists of a mixture of prevailing anatase phase and a small amount (~15%–20% of brookite, containing Fe3+ and nitrogen. By reusing dispersions of TiO2-1% Fe-N, high amounts of photocatalysts were deposited on the fabrics, and the photocatalytic activity was improved, especially under visible light. The treated fabrics exhibited specific antimicrobial features, which were dependent on their composition, microbial strain and incubation time. The in vitro biocompatibility evaluation on CCD-1070Sk dermal fibroblasts confirmed the absence of cytotoxicity after short-term exposure. These results highlight the potential of TiO2-1% Fe-N nanoparticles for further use in the development of innovative self-cleaning and antimicrobial photocatalytic cotton textiles. However, further studies are required in order to assess the long-term skin exposure effects and the possible particle release due to wearing.

  3. The encapsulation effect of UV molecular absorbers into biocompatible lipid nanoparticles

    Science.gov (United States)

    Lacatusu, Ioana; Badea, Nicoleta; Murariu, Alina; Meghea, Aurelia

    2011-12-01

    The efficiency of a cosmetic product depends not only on the active ingredients, but also on the carrier system devoted to improve its bioavailability. This article aims to encapsulate two couples of UV molecular absorbers, with a blocking action on both UV-A and UV-B domains, into efficient lipid nanoparticles. The effect of encapsulation on the specific properties such as sun protection factor and photostability behaviour has been demonstrated. The lipid nanoparticles with size range 30-350 nm and a polydispersity index between 0.217 and 0.244 are obtained using a modified high shear homogenisation method. The nanoparticles had spherical shapes with a single crystallisation form of lipid matrices characteristic for the least ordered crystal structure (α-form). The in vitro determination of photoprotection has led to high SPF ratings, with values of about 20, which assure a good photoprotection and filtering about 95% of UV radiation. The photoprotection effect after irradiation stage was observed to be increased more than twice compared to initial samples as a result of isomerisation phenomena. All the results have shown that good photoprotection effect and improved photostability could be obtained using such sunscreen couples, thus demonstrating that UV absorbers-solid lipid nanoparticles are promising carriers for cosmetic formulations.

  4. The encapsulation effect of UV molecular absorbers into biocompatible lipid nanoparticles

    Directory of Open Access Journals (Sweden)

    Lacatusu Ioana

    2011-01-01

    Full Text Available Abstract The efficiency of a cosmetic product depends not only on the active ingredients, but also on the carrier system devoted to improve its bioavailability. This article aims to encapsulate two couples of UV molecular absorbers, with a blocking action on both UV-A and UV-B domains, into efficient lipid nanoparticles. The effect of encapsulation on the specific properties such as sun protection factor and photostability behaviour has been demonstrated. The lipid nanoparticles with size range 30-350 nm and a polydispersity index between 0.217 and 0.244 are obtained using a modified high shear homogenisation method. The nanoparticles had spherical shapes with a single crystallisation form of lipid matrices characteristic for the least ordered crystal structure (α-form. The in vitro determination of photoprotection has led to high SPF ratings, with values of about 20, which assure a good photoprotection and filtering about 95% of UV radiation. The photoprotection effect after irradiation stage was observed to be increased more than twice compared to initial samples as a result of isomerisation phenomena. All the results have shown that good photoprotection effect and improved photostability could be obtained using such sunscreen couples, thus demonstrating that UV absorbers-solid lipid nanoparticles are promising carriers for cosmetic formulations.

  5. Biocompatibility Assessment of Polyethylene Glycol-Poly L-Lysine-Poly Lactic-Co-Glycolic Acid Nanoparticles In Vitro and In Vivo.

    Science.gov (United States)

    Guo, Liting; Chen, Baoan; Liu, Ran; Xia, Guohua; Wang, Yonglu; Li, Xueming; Wei, Chen; Wang, Xuemei; Jiang, Hulin

    2015-05-01

    The present study was designed to evaluate the biocompatibility of nanoparticles polyethylene glycol (PEG)-poly L-lysine (PLL)-poly lactic-co-glycolic acid copolymer (PLGA) (PEG-PLL-PLGA) before clinical application. We applied some tests to assess the safety of PEG-PLL-PLGA nanoparticles (NPs). There was low cytotoxicity of PEG-PLL-PLGA NPs in vitro as detected by MTT assay. Cell apoptosis and intracellular accumulation of PEG-PLL-PLGA were determined by FCM assay. The apoptotic rate induced by nanoparticles and the fluorescence intensity of intracellular daunorubicin (DNR) demonstrated that DNR-PEG-PLL-PLGA could be taken up by the mouse fibroblast cells (L929 cells). Hemolysis test and micronucleus (MN) assay demonstrated that the nanoparticles have no obviously blood toxicity and genotoxicity. DNR-PEG-PLL-PLGA NPs were injected into mice through tail vein to calculate the median lethal dose (LD50), the results showed that they had a wide safe scale. Blood was taken by removing the eyeball of mice to study the influence of DNR-PEG-PLL-PLGA in hepatic and renal functions. The results revealed that there was no significant difference as compared with the control group. Interestingly, the pathologic changes of heart, liver, spleen, lung and kidney were observed in nanoparticles treated mice. Thus, this study demonstrates that PEG-PLL-PLGA NPs appear to be highly biocompatible and safe nanoparticles that can be suitable for further application in the treatment of tumor.

  6. Gold nanoparticles prepared by laser ablation in aqueous biocompatible solutions: assessment of safety and biological identity for nanomedicine applications

    Directory of Open Access Journals (Sweden)

    Correard F

    2014-11-01

    Full Text Available Florian Correard,1,2 Ksenia Maximova,3 Marie-Anne Estève,1,2 Claude Villard,1 Myriam Roy,4 Ahmed Al-Kattan,3 Marc Sentis,3 Marc Gingras,4 Andrei V Kabashin,3 Diane Braguer1,2 1Aix Marseille Université, INSERM, CR02 UMR_S911, Marseille, France; 2APHM, Hôpital Timone, Marseille, France; 3Aix Marseille Université, CNRS, LP3 UMR 7341, Marseille, France; 4Aix Marseille Université, CNRS, CINAM, UMR 7325 Marseille, France Abstract: Due to excellent biocompatibility, chemical stability, and promising optical properties, gold nanoparticles (Au-NPs are the focus of research and applications in nanomedicine. Au-NPs prepared by laser ablation in aqueous biocompatible solutions present an essentially novel object that is unique in avoiding any residual toxic contaminant. This paper is conceived as the next step in development of laser-ablated Au-NPs for future in vivo applications. The aim of the study was to assess the safety, uptake, and biological behavior of laser-synthesized Au-NPs prepared in water or polymer solutions in human cell lines. Our results showed that laser ablation allows the obtaining of stable and monodisperse Au-NPs in water, polyethylene glycol, and dextran solutions. The three types of Au-NPs were internalized in human cell lines, as shown by transmission electron microscopy. Biocompatibility and safety of Au-NPs were demonstrated by analyzing cell survival and cell morphology. Furthermore, incubation of the three Au-NPs in serum-containing culture medium modified their physicochemical characteristics, such as the size and the charge. The composition of the protein corona adsorbed on Au-NPs was investigated by mass spectrometry. Regarding composition of complement C3 proteins and apolipoproteins, Au-NPs prepared in dextran solution appeared as a promising drug carrier. Altogether, our results revealed the safety of laser-ablated Au-NPs in human cell lines and support their use for theranostic applications. Keywords: protein

  7. Gelatin-based nanoparticles as DNA delivery systems: Synthesis, physicochemical and biocompatible characterization.

    Science.gov (United States)

    Morán, M C; Rosell, N; Ruano, G; Busquets, M A; Vinardell, M P

    2015-10-01

    The rapidly rising demand for therapeutic grade DNA molecules requires associated improvements in encapsulation and delivery technologies. One of the challenges for the efficient intracellular delivery of therapeutic biomolecules after their cell internalization by endocytosis is to manipulate the non-productive trafficking from endosomes to lysosomes, where degradation may occur. The combination of the endosomal acidity with the endosomolytic capability of the nanocarrier can increase the intracellular delivery of many drugs, genes and proteins, which, therefore, might enhance their therapeutic efficacy. Among the suitable compounds, the gelification properties of gelatin as well as the strong dependence of gelatin ionization with pH makes this compound an interesting candidate to be used to the effective intracellular delivery of active biomacromolecules. In the present work, gelatin (either high or low gel strength) and protamine sulfate has been selected to form particles by interaction of oppositely charged compounds. Particles in the absence of DNA (binary system) and in the presence of DNA (ternary system) have been prepared. The physicochemical characterization (particle size, polydispersity index and degree of DNA entrapment) have been evaluated. Cytotoxicity experiments have shown that the isolated systems and the resulting gelatin-based nanoparticles are essentially non-toxic. The pH-dependent hemolysis assay and the response of the nanoparticles co-incubated in buffers at defined pHs that mimic extracellular, early endosomal and late endo-lysosomal environments demonstrated that the nanoparticles tend to destabilize and DNA can be successfully released. It was found that, in addition to the imposed compositions, the gel strength of gelatin is a controlling parameter of the final properties of these nanoparticles. The results indicate that these gelatin-based nanoparticles have excellent properties as highly potent and non-toxic intracellular delivery

  8. A "turn-off" luminescence resonance energy transfer aptamer sensor based on near-infrared upconverting NaYF4∶Yb3+, Tm3+ nanoparticles as donors and gold nanorods as acceptors

    Institute of Scientific and Technical Information of China (English)

    Hong-Qi Chen; Juan Xu; Fei Yuan; Yong Wu; Yi-Yan Zhang; Lun Wang

    2013-01-01

    Near-infrared upconverting NaYF4:Yb3+,Tm3+ nanophosphors modified with poly(acrylic acid) were prepared and characterized by transmission electron microscopy and luminescence spectroscopy.Based on the observed overlap between the emission spectrum of the NaYF4∶Yb3+,Tm3+ nanophosphors and the absorption spectrum of the gold nanorods,we believe that a new "turn-off" luminescence resonance energy transfer aptamer sensor was constructed for sensing thrombin in near-infrared region.

  9. Sodium-22-radiolabeled silica nanoparticles as new radiotracer for biomedical applications: in vivo positron emission tomography imaging, biodistribution, and biocompatibility

    Directory of Open Access Journals (Sweden)

    Al Faraj A

    2015-10-01

    Full Text Available Achraf Al Faraj,1 Basem Alotaibi,2 Abjal Pasha Shaik,3 Khaled Z Shamma,1 Ibrahim Al Jammaz,2 Jürgen Gerl4 1Molecular and Cellular Imaging Lab, Department of Radiological Sciences, College of Applied Medical Sciences, King Saud University, 2Cyclotron and Radiopharmaceutical Department, King Faisal Specialist Hospital and Research Centre, 3Department of Clinical Lab Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 4GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany Abstract: Despite their advantageous chemical properties for nuclear imaging, radioactive sodium-22 (22Na tracers have been excluded for biomedical applications because of their extremely long lifetime. In the current study, we proposed, for the first time, the use of 22Na radiotracers for pre-clinical applications by efficiently loading with silica nanoparticles (SiNPs and thus offering a new life for this radiotracer. Crown-ether-conjugated SiNPs (300 nm; -0.18±0.1 mV were successfully loaded with 22Na with a loading efficacy of 98.1%±1.4%. Noninvasive positron emission tomography imaging revealed a transient accumulation of 22Na-loaded SiNPs in the liver and to a lower extent in the spleen, kidneys, and lung. However, the signal gradually decreased in a time-dependent manner to become not detectable starting from 2 weeks postinjection. These observations were confirmed ex vivo by quantifying 22Na radioactivity using γ-counter and silicon content using inductively coupled plasma-mass spectrometry in the blood and the different organs of interest. Quantification of Si content in the urine and feces revealed that SiNPs accumulated in the organs were cleared from the body within a period of 2 weeks and completely in 1 month. Biocompatibility evaluations performed during the 1-month follow-up study to assess the possibility of synthesized nanocarriers to induce oxidative stress or DNA damage confirmed their safety for

  10. Biocompatibility of ferritin-based nanoparticles as targeted MRI contrast agents.

    Science.gov (United States)

    Charlton, Jennifer R; Pearl, Valeria M; Denotti, Anna R; Lee, Jonathan B; Swaminathan, Sundararaman; Scindia, Yogesh M; Charlton, Nathan P; Baldelomar, Edwin J; Beeman, Scott C; Bennett, Kevin M

    2016-08-01

    Ferritin is a naturally occurring iron storage protein, proposed as a clinically relevant nanoparticle with applications as a diagnostic and therapeutic agent. Cationic ferritin is a targeted, injectable contrast agent to measure kidney microstructure with MRI. Here, the toxicity of horse spleen ferritin is assessed as a step to clinical translation. Adult male mice received cationic, native and high dose cationic ferritin (CF, NF, or HDCF) or saline and were monitored for 3weeks. Transient weight loss occurred in the ferritin groups with no difference in renal function parameters. Ferritin-injected mice demonstrated a lower serum iron 3weeks after administration. In ferritin-injected animals pre-treated with hydrocortisone, there were no structural or weight differences in the kidneys, liver, lung, heart, or spleen. This study demonstrates a lack of significant detrimental effects of horse-derived ferritin-based nanoparticles at MRI-detectable doses, allowing further exploration of these agents in basic research and clinical diagnostics. PMID:27071333

  11. Caveolae-mediated endocytosis of biocompatible gold nanoparticles in living Hela cells

    International Nuclear Information System (INIS)

    Efficient intracellular delivery of gold nanoparticles (AuNPs) and unraveling the mechanism underlying the intracellular delivery are essential for advancing the applications of AuNPs toward in vivo imaging and therapeutic interventions. We employed fluorescence microscopy to investigate the internalization mechanism of small-size AuNPs by living Hela cells. Herein, we found that the caveolae-mediated endocytosis was the dominant pathway for the intracellular delivery of small-size AuNPs. The intracellular delivery was suppressed when we depleted the cholesterol with methyl-β-cyclodextrin (MβCD); in contrast, the sucrose that disrupts the formation of clathrin-mediated endocytosis did not block the endocytosis of AuNPs. Meanwhile, we examined the intracellular localization of AuNPs in endocytic vesicles by fluorescent colocalization. This work would provide a potential technique to study the intracellular delivery of small-size nanoparticles for biomedical applications. (paper)

  12. Enhanced solubility and functionality of valrubicin (AD-32 against cancer cells upon encapsulation into biocompatible nanoparticles

    Directory of Open Access Journals (Sweden)

    Sabnis N, Nair M

    2012-02-01

    Full Text Available Nirupama Sabnis1, Maya Nair1, Mervyn Israel2, Walter J McConathy3, Andras G Lacko11University of North Texas Health Science Center, Fort Worth, TX, 2University of Tennessee Health Science Center, Memphis, TN, 3Texas Tech University Health Sciences Center–Permian Basin, Odessa, TX, USAAbstract: Among numerous drug-delivery approaches, reconstituted high-density lipoprotein (rHDL nanocarriers have proven particularly applicable for delivering highly hydrophobic drugs. In this study, we have investigated the enhancement of the therapeutic impact of valrubicin (AD-32, an antineoplastic agent that has been limited to intravesicular application against bladder cancer, despite the encouraging original preclinical data. Earlier studies validated the superior therapeutic efficacy of AD-32 over doxorubicin. In the present study, rHDL/AD-32 nanoparticles were formulated and characterized with regard to encapsulation efficiency, physicochemical properties, selective toxicity, and receptor-mediated uptake. The half maximal inhibitory concentration values (IC50 for rHDL/AD-32 nanoparticles were 1.8 and 2.6 times lower than the free AD-32 for prostate (PC-3 and ovarian (SKOV-3 cancer cell lines, respectively, whereas nonmalignant cell lines demonstrated 5 and 1.48 times higher IC50 doses with rHDL/AD-32 formulations. The data obtained demonstrated effective receptor-mediated uptake of AD-32 from the rHDL nanocarriers by PC-3 and SKOV-3 cancer cells via a targeted drug-delivery process. The rHDL/AD-32 formulation was stable for 6 months when stored at 4°C or at –20°C, as 92% of the AD-32 was retained in the nanoparticles. The findings from this study show that the rHDL/AD-32 formulation can overcome the solubility barriers of AD-32 and thus serve as an effective systemically administered chemotherapeutic agent.Keywords: AD-32, rHDL, nanoparticles, targeted drug delivery, selective drug delivery

  13. Biocompatibility, endocytosis, and intracellular trafficking of mesoporous silica and polystyrene nanoparticles in ovarian cancer cells: effects of size and surface charge groups

    Science.gov (United States)

    Ekkapongpisit, Maneerat; Giovia, Antonino; Follo, Carlo; Caputo, Giuseppe; Isidoro, Ciro

    2012-01-01

    Background and methods Nanoparticles engineered to carry both a chemotherapeutic drug and a sensitive imaging probe are valid tools for early detection of cancer cells and to monitor the cytotoxic effects of anticancer treatment simultaneously. Here we report on the effect of size (10–30 nm versus 50 nm), type of material (mesoporous silica versus polystyrene), and surface charge functionalization (none, amine groups, or carboxyl groups) on biocompatibility, uptake, compartmentalization, and intracellular retention of fluorescently labeled nanoparticles in cultured human ovarian cancer cells. We also investigated the involvement of caveolae in the mechanism of uptake of nanoparticles. Results We found that mesoporous silica nanoparticles entered via caveolae-mediated endocytosis and reached the lysosomes; however, while the 50 nm nanoparticles permanently resided within these organelles, the 10 nm nanoparticles soon relocated in the cytoplasm. Naked 10 nm mesoporous silica nanoparticles showed the highest and 50 nm carboxyl-modified mesoporous silica nanoparticles the lowest uptake rates, respectively. Polystyrene nanoparticle uptake also occurred via a caveolae-independent pathway, and was negatively affected by serum. The 30 nm carboxyl-modified polystyrene nanoparticles did not localize in lysosomes and were not toxic, while the 50 nm amine-modified polystyrene nanoparticles accumulated within lysosomes and eventually caused cell death. Ovarian cancer cells expressing caveolin-1 were more likely to endocytose these nanoparticles. Conclusion These data highlight the importance of considering both the physicochemical characteristics (ie, material, size and surface charge on chemical groups) of nanoparticles and the biochemical composition of the cell membrane when choosing the most suitable nanotheranostics for targeting cancer cells. PMID:22904626

  14. In vitro and in vivo impact of silica nanoparticle design on biocompatibility

    Science.gov (United States)

    Yu, Tian

    Silica nanoparticles (SiO2) have utility in a wide range of applications, such as biologic delivery platforms, imaging and diagnostic agents, and targeted therapeutic carriers. Recent improvements in regulating the geometry, porosity, and surface characteristics of SiO2 have further facilitated their biomedical applications. Concerns however remain about the toxic effects of SiO2 upon exposure to biological systems. The impacts of geometry, porosity, and surface characteristics of SiO 2 on cellular toxicity and hemolytic activity were explored. It was shown that surface characteristics and porosity govern cellular toxicity. The cellular association of SiO2 increased in the following order: mesoporous SiO2 (aspect ratio 1, 2, 4, 8) in vivo toxicity, biodistribution and pharmacokinetics of SiO2 were mainly influenced by nanoparticle porosity and surface characteristics. The maximum tolerated dose (MTD) increased in the following order: Mesoporous SiO2 (aspect ratio 1, 2, 8) at 30 -- 65 mg/kg < amine-modified mesoporous SiO2 (aspect ratio 1, 2, 8) at 100 -- 150 mg/kg < unmodified or amine-modified nonporous SiO2 at 450 mg/kg. The adverse reactions above MTDs were primarily caused by the mechanical obstruction of SiO2 in the vasculature that led to congestion in multiple vital organs and subsequent organ failure. The nanoparticles were taken up extensively by the liver and spleen. Mesoporous SiO2 exhibited higher accumulation in the lung than nonporous SiO 2 of similar size. This accumulation was reduced by primary amine modification. Increasing the aspect ratio of amine-modified mesoporous SiO2 from 1 to 8 resulted in increased accumulation in the lung. These studies provide critical guidelines in rational design of SiO 2 for nanomedicine applications.

  15. The Effect of Polymeric Nanoparticles on Biocompatibility of Carrier Red Blood Cells.

    Science.gov (United States)

    Pan, Daniel; Vargas-Morales, Omayra; Zern, Blaine; Anselmo, Aaron C; Gupta, Vivek; Zakrewsky, Michael; Mitragotri, Samir; Muzykantov, Vladimir

    2016-01-01

    Red blood cells (RBCs) can be used for vascular delivery of encapsulated or surface-bound drugs and carriers. Coupling to RBC prolongs circulation of nanoparticles (NP, 200 nm spheres, a conventional model of polymeric drug delivery carrier) enabling their transfer to the pulmonary vasculature without provoking overt RBC elimination. However, little is known about more subtle and potentially harmful effects of drugs and drug carriers on RBCs. Here we devised high-throughput in vitro assays to determine the sensitivity of loaded RBCs to osmotic stress and other damaging insults that they may encounter in vivo (e.g. mechanical, oxidative and complement insults). Sensitivity of these tests is inversely proportional to RBC concentration in suspension and our results suggest that mouse RBCs are more sensitive to damaging factors than human RBCs. Loading RBCs by NP at 1:50 ratio did not affect RBCs, while 10-50 fold higher NP load accentuated RBC damage by mechanical, osmotic and oxidative stress. This extensive loading of RBC by NP also leads to RBCs agglutination in buffer; however, addition of albumin diminished this effect. These results provide a template for analyses of the effects of diverse cargoes loaded on carrier RBCs and indicate that: i) RBCs can tolerate carriage of NP at doses providing loading of millions of nanoparticles per microliter of blood; ii) tests using protein-free buffers and mouse RBCs may overestimate adversity that may be encountered in humans. PMID:27003833

  16. The Effect of Polymeric Nanoparticles on Biocompatibility of Carrier Red Blood Cells.

    Directory of Open Access Journals (Sweden)

    Daniel Pan

    Full Text Available Red blood cells (RBCs can be used for vascular delivery of encapsulated or surface-bound drugs and carriers. Coupling to RBC prolongs circulation of nanoparticles (NP, 200 nm spheres, a conventional model of polymeric drug delivery carrier enabling their transfer to the pulmonary vasculature without provoking overt RBC elimination. However, little is known about more subtle and potentially harmful effects of drugs and drug carriers on RBCs. Here we devised high-throughput in vitro assays to determine the sensitivity of loaded RBCs to osmotic stress and other damaging insults that they may encounter in vivo (e.g. mechanical, oxidative and complement insults. Sensitivity of these tests is inversely proportional to RBC concentration in suspension and our results suggest that mouse RBCs are more sensitive to damaging factors than human RBCs. Loading RBCs by NP at 1:50 ratio did not affect RBCs, while 10-50 fold higher NP load accentuated RBC damage by mechanical, osmotic and oxidative stress. This extensive loading of RBC by NP also leads to RBCs agglutination in buffer; however, addition of albumin diminished this effect. These results provide a template for analyses of the effects of diverse cargoes loaded on carrier RBCs and indicate that: i RBCs can tolerate carriage of NP at doses providing loading of millions of nanoparticles per microliter of blood; ii tests using protein-free buffers and mouse RBCs may overestimate adversity that may be encountered in humans.

  17. Poly(trimethylene carbonate)/Poly(malic acid) Amphiphilic Diblock Copolymers as Biocompatible Nanoparticles.

    Science.gov (United States)

    Barouti, Ghislaine; Khalil, Ali; Orione, Clement; Jarnouen, Kathleen; Cammas-Marion, Sandrine; Loyer, Pascal; Guillaume, Sophie M

    2016-02-18

    Amphiphilic polycarbonate-poly(hydroxyalkanoate) diblock copolymers, namely, poly(trimethylene carbonate) (PTMC)-b-poly(β-malic acid) (PMLA), are reported for the first time. The synthetic strategy relies on commercially available catalysts and initiator. The controlled ring-opening polymerization (ROP) of trimethylene carbonate (TMC) catalyzed by the organic guanidine base 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), associated with iPrOH as an initiator, provided iPrO-PTMC-OH, which served as a macroinitiator in the controlled ROP of benzyl β-malolactonate (MLABe) catalyzed by the neodymium triflate salt (Nd(OTf)3). The resulting hydrophobic iPrO-PTMC-b-PMLABe-OH copolymers were then hydrogenolyzed into the parent iPrO-PTMC-b-PMLA-OH copolymers. A range of well-defined copolymers, featuring different sizes of segments (Mn,NMR up to 9300 g mol(-1) ; ÐM =1.28-1.40), were thus isolated in gram quantities, as evidenced by NMR spectroscopy, size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry, and contact angle analyses. Subsequently, PTMC-b-PMLA copolymers with different hydrophilic weight fractions (11-75 %) self-assembled in phosphate-buffered saline upon nanoprecipitation into well-defined nano-objects with Dh =61-176 nm, a polydispersity index nanoparticles demonstrated no significant effect on cell viability at low concentrations, and a very low cytotoxicity at high concentrations only for PTMC-b-PMLA copolymers exhibiting hydrophilic fractions over 47 %, thus illustrating the potential of these copolymers as promising nanoparticles.

  18. Increased cellular uptake of biocompatible superparamagnetic iron oxide nanoparticles into malignant cells by an external magnetic field.

    Science.gov (United States)

    Prijic, Sara; Scancar, Janez; Romih, Rok; Cemazar, Maja; Bregar, Vladimir B; Znidarsic, Andrej; Sersa, Gregor

    2010-07-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) are used as delivery systems for different therapeutics including nucleic acids for magnetofection-mediated gene therapy. The aim of our study was to evaluate physicochemical properties, biocompatibility, cellular uptake and trafficking pathways of the custom-synthesized SPIONs for their potential use in magnetofection. Custom-synthesized SPIONs were tested for size, shape, crystalline composition and magnetic behavior using a transmission electron microscope, X-ray diffractometer and magnetometer. SPIONs were dispersed in different aqueous media to obtain ferrofluids, which were tested for pH and stability using a pH meter and zetameter. Cytotoxicity was determined using the MTS and clonogenic assays. Cellular uptake and trafficking pathways were qualitatively evaluated by transmission electron microscopy and quantitatively by inductively coupled plasma atomic emission spectrometry. SPIONs were composed of an iron oxide core with a diameter of 8-9 nm, coated with a 2-nm-thick layer of silica. SPIONs, dispersed in 0.9% NaCl solution, resulted in a stable ferrofluid at physiological pH for several months. SPIONs were not cytotoxic in a broad range of concentrations and were readily internalized into different cells by endocytosis. Exposure to neodymium-iron-boron magnets significantly increased the cellular uptake of SPIONs, predominantly into malignant cells. The prepared SPIONs displayed adequate physicochemical and biomedical properties for potential use in magnetofection. Their cellular uptake was dependent on the cell type, and their accumulation within the cells was dependent on the duration of exposure to an external magnetic field. PMID:20602230

  19. Biocompatibility, endocytosis, and intracellular trafficking of mesoporous silica and polystyrene nanoparticles in ovarian cancer cells: effects of size and surface charge groups

    Directory of Open Access Journals (Sweden)

    Ekkapongpisit M

    2012-07-01

    Full Text Available Maneerat Ekkapongpisit,1 Antonino Giovia,1 Carlo Follo,1 Giuseppe Caputo,2,3 Ciro Isidoro11Laboratory of Molecular Pathology and Nanobioimaging, Department of Health Sciences, Università del Piemonte Orientale “A Avogadro”, Novara, 2Dipartimento di Chimica dell’Università di Torino, Torino, 3Cyanine Technology SpA, Torino, ItalyBackground and methods: Nanoparticles engineered to carry both a chemotherapeutic drug and a sensitive imaging probe are valid tools for early detection of cancer cells and to monitor the cytotoxic effects of anticancer treatment simultaneously. Here we report on the effect of size (10–30 nm versus 50 nm, type of material (mesoporous silica versus polystyrene, and surface charge functionalization (none, amine groups, or carboxyl groups on biocompatibility, uptake, compartmentalization, and intracellular retention of fluorescently labeled nanoparticles in cultured human ovarian cancer cells. We also investigated the involvement of caveolae in the mechanism of uptake of nanoparticles.Results: We found that mesoporous silica nanoparticles entered via caveolae-mediated endocytosis and reached the lysosomes; however, while the 50 nm nanoparticles permanently resided within these organelles, the 10 nm nanoparticles soon relocated in the cytoplasm. Naked 10 nm mesoporous silica nanoparticles showed the highest and 50 nm carboxyl-modified mesoporous silica nanoparticles the lowest uptake rates, respectively. Polystyrene nanoparticle uptake also occurred via a caveolae-independent pathway, and was negatively affected by serum. The 30 nm carboxyl-modified polystyrene nanoparticles did not localize in lysosomes and were not toxic, while the 50 nm amine-modified polystyrene nanoparticles accumulated within lysosomes and eventually caused cell death. Ovarian cancer cells expressing caveolin-1 were more likely to endocytose these nanoparticles.Conclusion: These data highlight the importance of considering both the

  20. Heating ability and biocompatibility study of silica-coated magnetic nanoparticles as heating mediators for magnetic hyperthermia and magnetically triggered drug delivery systems

    Indian Academy of Sciences (India)

    Meysam Soleymani; Mohammad Edrissi

    2015-10-01

    The aim of this study is to prepare core–shell La0.73Sr0.27MnO3 –silica nanoparticles and evaluating their heat generation ability under the safe alternating magnetic field ( = 100 kHz and = 10–20 kA m−1) for potential applications in magnetic fluid hyperthermia and magnetically triggered drug delivery systems. The magnetic cores of La0.73Sr0.27MnO3 with an average particle size of 54 nm were synthesized by the citrate–gel method. Then, the Stober method was applied to encapsulate nanoparticles with 5-nm-thick silica shell. The core–shell structure of nanoparticles was confirmed by X-ray diffraction, fourier transform infrared spectroscopy and transmission electron microscopy analyses. Cytotoxicity of bare and silica-coated nanoparticles was evaluated by methyl thiazol tetrazolium bromide assay with MCF-7 cell line. The results revealed that the both samples have negligible toxicity below 500 g ml−1 and silica coating can improve the biocompatibility of nanoparticle. In addition, calorimetric measurements were used to determine the heating efficiency of the core–shell nanostructures in aqueous medium. The results showed that the heat generated of the prepared sample could be safely controlled in the range of 40–60°C which is suitable for biomedical applications.

  1. Chitosan–tripolyphosphate nanoparticles as Arrabidaea chica standardized extract carrier: synthesis, characterization, biocompatibility, and antiulcerogenic activity

    Directory of Open Access Journals (Sweden)

    Servat-Medina L

    2015-06-01

    and polymers. The NP biocompatibility was evaluated using human skin fibroblasts. AcE-NP demonstrated capability of maintaining cell viability at the lowest concentrations tested, stimulating cell proliferation at higher concentrations. Antiulcerogenic activity of AcE-NP was also evaluated with an acute gastric ulcer experimental model induced by ethanol and indomethacin. NPs loaded with A. chica extract reduced the ulcerative lesion index using lower doses compared with the free extract, suggesting that extract encapsulation in chitosan NPs allowed for a dose reduction for a gastroprotective effect. The AcE encapsulation offers an approach for further application of the A. chica extract that could be considered a potential candidate for ulcer-healing pharmaceutical systems. Keywords: natural product, Arrabidaea chica, chitosan, nanoparticle, plant extract, herbal drug, ulcer healing

  2. Surface modification of silica particles and upconverting particles using click chemistry

    OpenAIRE

    Mader, Heike Sabine

    2010-01-01

    Upconverting nanoparticles (UCNPs) of the NaYF4 type with narrow size distribution from 60 to 90 nm, were prepared using the established co-precipitation method. The particles were codoped using Yb3+ as the sensitizer ion, Er3+, Tm3+ or Ho3+, respectively as the emitting activator ions. Erbium doped particles displayed the brightest luminescence (green and red). A dopant ratio of 25% Yb3+ and 2% Er3+ proved to be the best composition to enable a partial phase transfer from the cubic alpha-NaY...

  3. Preparation and in vitro evaluation of Methotrexate-loaded magnetic nanoparticles modified with biocompatible copolymers.

    Science.gov (United States)

    Jahangiri, Sahar; Akbarzadeh, Abolfazl

    2016-11-01

    Superparamagnetic iron oxide nanoparticles (SPION) are attractive materials that have been widely used in medicine for drug delivery, diagnostic imaging and therapeutic applications. In our study, SPION and the anticancer drug, Methotrexate, were encapsulated into polycaprolactone-polyethylene glycol (PCL-PEG) nanoparticles for local treatment. The magnetic properties conferred by SPION could help to maintain the nanoparticles in the joint with an external magnet. The drug encapsulation efficiency achieved for Fe3O4 magnetic nanoparticles modified with PCL-PEG copolymer was 92.36%. There is potential for use of these nanoparticles for biomedical application. PMID:26479846

  4. Biocompatible micro-sized cell culture chamber for the detection of nanoparticle-induced IL8 promoter activity on a small cell population

    Directory of Open Access Journals (Sweden)

    Oostingh Gertie

    2011-01-01

    Full Text Available Abstract In most conventional in vitro toxicological assays, the response of a complete cell population is averaged, and therefore, single-cell responses are not detectable. Such averaging might result in misinterpretations when only individual cells within a population respond to a certain stimulus. Therefore, there is a need for non-invasive in vitro systems to verify the toxicity of nanoscale materials. In the present study, a micro-sized cell culture chamber with a silicon nitride membrane (0.16 mm2 was produced for cell cultivation and the detection of specific cell responses. The biocompatibility of the microcavity chip (MCC was verified by studying adipogenic and neuronal differentiation. Thereafter, the suitability of the MCC to study the effects of nanoparticles on a small cell population was determined by using a green fluorescence protein-based reporter cell line. Interleukin-8 promoter (pIL8 induction, a marker of an inflammatory response, was used to monitor immune activation. The validation of the MCC-based method was performed using well-characterized gold and silver nanoparticles. The sensitivity of the new method was verified comparing the quantified pIL8 activation via MCC-based and standard techniques. The results proved the biocompatibility and the sensitivity of the microculture chamber, as well as a high optical quality due to the properties of Si3N4. The MCC-based method is suited for threshold- and time-dependent analysis of nanoparticle-induced IL8 promoter activity. This novel system can give dynamic information at the level of adherent single cells of a small cell population and presents a new non-invasive in vitro test method to assess the toxicity of nanomaterials and other compounds. PACS: 85.35.Be, 81.16.Nd, 87.18.Mp

  5. Biocompatible micro-sized cell culture chamber for the detection of nanoparticle-induced IL8 promoter activity on a small cell population

    Science.gov (United States)

    Kohl, Yvonne; Oostingh, Gertie J.; Sossalla, Adam; Duschl, Albert; von Briesen, Hagen; Thielecke, Hagen

    2011-08-01

    In most conventional in vitro toxicological assays, the response of a complete cell population is averaged, and therefore, single-cell responses are not detectable. Such averaging might result in misinterpretations when only individual cells within a population respond to a certain stimulus. Therefore, there is a need for non-invasive in vitro systems to verify the toxicity of nanoscale materials. In the present study, a micro-sized cell culture chamber with a silicon nitride membrane (0.16 mm2) was produced for cell cultivation and the detection of specific cell responses. The biocompatibility of the microcavity chip (MCC) was verified by studying adipogenic and neuronal differentiation. Thereafter, the suitability of the MCC to study the effects of nanoparticles on a small cell population was determined by using a green fluorescence protein-based reporter cell line. Interleukin-8 promoter (pIL8) induction, a marker of an inflammatory response, was used to monitor immune activation. The validation of the MCC-based method was performed using well-characterized gold and silver nanoparticles. The sensitivity of the new method was verified comparing the quantified pIL8 activation via MCC-based and standard techniques. The results proved the biocompatibility and the sensitivity of the microculture chamber, as well as a high optical quality due to the properties of Si3N4. The MCC-based method is suited for threshold- and time-dependent analysis of nanoparticle-induced IL8 promoter activity. This novel system can give dynamic information at the level of adherent single cells of a small cell population and presents a new non-invasive in vitro test method to assess the toxicity of nanomaterials and other compounds. PACS: 85.35.Be, 81.16.Nd, 87.18.Mp

  6. Research on optical biosensor with up-converting phosphor marker

    Institute of Scientific and Technical Information of China (English)

    Yongkai Zhao; Xiangzhao Wang; Lei Zhou; Jing Wang; Lihua Huang; Zhongqiang Yan; Huijie Huang; Ruifu Yang; Lei Liu; Bingqiang Ren

    2006-01-01

    @@ An optical biosensor with up-converting phosphor (UCP) marker is developed for the sensitive rapid immunoassay to the specific biomolecule. UCP can emit visible light when excited by infrared light.

  7. Synthesis of protein-coated biocompatible methotrexate-loaded PLA-PEG-PLA nanoparticles for breast cancer treatment

    OpenAIRE

    Salam Massadeh; Manal Alaamery; Shatha Al-Qatanani; Saqer Alarifi; Shahad Bawazeer; Yusra Alyafee

    2016-01-01

    Background: PLA-PEG-PLA triblock polymer nanoparticles are promising tools for targeted dug delivery. The main aim in designing polymeric nanoparticles for drug delivery is achieving a controlled and targeted release of a specific drug at the therapeutically optimal rate and choosing a suitable preparation method to encapsulate the drug efficiently, which depends mainly on the nature of the drug (hydrophilic or hydrophobic). In this study, methotrexate (MTX)-loaded nanoparticles were prepared...

  8. Development of Up-Converting Phosphor Immunochromatography Test for Quantitative Detection of Enrofloxacin

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An up-converting phosphor (UCP) immunochromatography test was developed for the detection of enrofloxacin (ENR). The anti-ENR monoclonal was conjugated to the up-converting phosphor particles while the ENR-BSA immobilized on the nitrocellulose membrane

  9. Development of Up-Converting Phosphor Immunochromatography Test for Quantitative Detection of Sulfadiazin

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An up-converting phosphor (UCP) immunochromatography test was developed for the detection of sulfadiazine (SD). The anti-SD monoclonal was conjugated to the up-converting phosphor particles while the SD-BSA immobilized on the

  10. Enhanced bio-compatibility of ferrofluids of self-assembled superparamagnetic iron oxide-silica core-shell nanoparticles

    Digital Repository Service at National Institute of Oceanography (India)

    Narayanan, T.N; Mary, A; Swalih, P.K.A; Kumar, D.S.; Makarov, D.; Albrecht, M.; Puthumana, J.; Anas, A; Anantharaman, A

    -interacting, monodispersed and hence the synthesis of such nanostructures has great relevance in the realm of nanoscience. Silica-coated superparamagnetic iron oxide nanoparticles based ferrofluids were prepared using polyethylene glycol as carrier fluid by employing a...

  11. Plasmon enhanced upconversion luminescence near gold nanoparticles - Simulation and analysis of the interactions

    CERN Document Server

    Fischer, Stefan; von Plessen, Gero; Krämer, Karl W; Biner, Daniel; Steinkemper, Heiko; Hermle, Martin; Goldschmidt, Jan C

    2011-01-01

    We investigate plasmon resonances in gold nanoparticles to enhance the quantum yield of upconverting materials. For this purpose, we use a rate equation model that describes the upconversion of trivalent erbium based upconverters. Changes of the optical field acting on the upconverter and the changes to the transition probabilities of the upconverter in the proximity of a gold nanoparticle are calculated using Mie theory and exact electrodynamic theory. With this data, the influence on the luminescence of the upconverter is determined using the rate equation model. The results show that upconversion luminescence can be increased in the proximity of a spherical gold nanoparticle due to the change in the optical field and the modification of the transition rates.

  12. Biocompatible synthesis of silver nanoparticles (AgNPs using marine Vibrio sp. and study their pharmacological applications

    Directory of Open Access Journals (Sweden)

    M. Surya

    2015-09-01

    Full Text Available This report presents a rapid and a green biogenic approach for the biosynthesis of silver nanoparticles using marine bacteria such as Vibrio sp. The bioactive compounds of Vibrio sp. induced the reduction of Ag+ ions from AgNO3, which resulted in the formation of bacterial mediated silver nanoparticles (AgNPs. The reduction of Ag+ ions to elemental silver was characterized by UV-vis spectroscopy, Fourier transform infra-red spectroscopy (FTIR, Scanning electron microscopy (SEM and Dynamic light scattering (DLS. The nanoparticles show maximum absorbance at 421 nm on ultraviolet-visible spectra. The presence of biomolecules were identified by Fourier transform–infrared spectroscopy. The bioactive compounds and nanoparticles were found to direct different shape and sized and their size/ shape were varied. The silver nanoparticle synthesized were spherical, in the range of 40-80 nm in size. In antimicrobial screening, all the pathogens were fairly affected and nil effect was not observed in the test samples, In bacteria, the test sample was most effective against Enterococcus faecalis B2 and Salmonella typhimurium B5. In fungi, which was effective against Candida albicans F1, Microsporum canis F3 and Trichophyton rubrum F4.

  13. Single particle optical investigation of gold shell enhanced upconverted fluorescence emission

    Science.gov (United States)

    Green, Kory; Lim, Shuang Fang; Hallen, Hans

    2014-03-01

    Upconverting nanoparticles (UCNPs) excited in the near IR offer novel advantages as fluorescent contrast agents, allowing for background free bio-imaging. However, their fluorescence brightness is hampered by low quantum efficiency due to the low absorption cross section of Ytterbium and Erbium ions in the near IR. We enhance the efficiency of these particles by investigating the plasmonic coupling of 30nm diameter core NaYF4: Yb, Er upconverting particles (UCNPs) with a gold shell coating. An enhancement of green emission by a factor of five and a three times overall increase in emission intensity has been achieved for single particle spectra. UV-Vis absorption has confirmed the surface plasmon resonance (SPR) of the gold shell to the near IR and transmission electron microscope (TEM) images demonstrates successful growth of a gold shell around the upconversion particle. Time-resolved spectroscopy shows that gold shell coupling changes the lifetime of the energy levels of the Erbium ion that are relevant to the emission process.

  14. Anthelmintic Effect of Biocompatible Zinc Oxide Nanoparticles (ZnO NPs on Gigantocotyle explanatum, a Neglected Parasite of Indian Water Buffalo.

    Directory of Open Access Journals (Sweden)

    Yasir Akhtar Khan

    Full Text Available Helminth parasites of veterinary importance cause huge revenue losses to agrarian economy worldwide. With the emergence of drug resistance against the current formulations, there is a need to focus on the alternative approaches in order to control this menace. In the present study, biocompatible zinc oxide nanoparticles (ZnO NPs were used to see their in vitro effect on the biliary amphistomes, Gigantocotyle explanatum, infecting Bubalus bubalis because these nanoparticles are involved in generation of free radicals that induce oxidative stress, resulting in disruption of cellular machinery. The ZnO NPs were synthesized by using egg albumin as a biotemplate and subsequently characterized by Scanning Electron Microscopy (SEM, Transmission Electron Microscopy (TEM, X-ray Diffraction and Spectrophotometrical, which showed that ZnO NPs were highly purified wurtzite type polycrystals, with a mean size of 16.7 nm. When the parasites were treated with lower concentrations (0.004% and 0.008% of the ZnO NPs, the worms mounted a protective response by stimulating the antioxidant system but the treatment of G. explanatum with 0.012% ZnO NPs produced significant inhibition of the antioxidant enzymes like superoxide dismutase (SOD (p< 0.05 and glutathione S- transferase (GST (p<0.01, while the level of malondialdehyde (MDA, a lipid peroxidation marker, was significantly (p< 0.01 elevated. SEM and histopathology revealed pronounced tegumental damage showing the disruption of surface papillae and the annulations, particularly in the posterior region near acetabulum. The under expression of a number of polypeptides, loss of worm motility in a time dependent manner, further reflect strong anthelmintic potential of ZnO NPs. It can be concluded that the anthelmintic effect might be due to the production of reactive oxygen species that target a variety of macromolecules such as nucleic acid, protein and lipids which are involved in different cellular processes.

  15. pH-Sensitive Biocompatible Nanoparticles of Paclitaxel-Conjugated Poly(styrene-co-maleic acid) for Anticancer Drug Delivery in Solid Tumors of Syngeneic Mice.

    Science.gov (United States)

    Dalela, Manu; Shrivastav, T G; Kharbanda, Surender; Singh, Harpal

    2015-12-01

    In the present study, we have synthesized poly(styrene-co-maleic anhydride), a biocompatible copolymer that was further conjugated with paclitaxel (PTX) via ester linkage and self-assembled to form poly(styrene-co-maleic acid)-paclitaxel (PSMAC-PTX) nanoparticles (NPs). The in vitro release of PTX from PSMAC-PTX NPs showed a higher release at lower pH than at the physiological pH of 7.4, confirming its pH-dependent release. The cell viability of PSMAC-PTX nanoparticles was evaluated using MTT assay. IC50 values of 9.05-18.43 ng/mL of PTX equivalent were observed in various cancer cell lines after 72 h of incubation. Confocal microscopy, Western blotting, and Flow cytometry results further supported that the cellular uptake and apoptosis of cancer cells with PSMAC-PTX NPs. Pharmacokinetic studies revealed that the conjugation of PTX to the PSMAC co-polymer not only increased the plasma and tumor C(max) of PTX but also prolonged its plasma half-life and retention in tumor via enhanced permeability and retention (EPR) effect. Administration of PSMAC-PTX NPs showed significant tumor growth inhibition with improved apoptosis effects in vivo on Ehrlich Ascites Tumor (EAT)-bearing BALB/c syngeneic mice in comparison with Taxol, without showing any cytotoxicity. On the basis of preliminary results, no subacute toxicity was observed in major organs, tissues and hematological system up to a dosage of 60 mg/kg body weight in mice. Therefore, PSMAC-PTX NPs may be considered as an alternative nanodrug delivery system for the delivery of PTX in solid tumors. PMID:26528585

  16. Synthesis of biocompatible poly(ε-caprolactone-block-poly(propylene adipate copolymers appropriate for drug nanoencapsulation in the form of core-shell nanoparticles

    Directory of Open Access Journals (Sweden)

    Nanaki SG

    2011-11-01

    Full Text Available Stavroula G Nanaki1, Kostas Pantopoulos2, Dimitrios N Bikiaris11Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Macedonia, Greece; 2Lady Davis Institute for Medical Research and Department of Medicine, McGill University, Montreal, Quebec, CanadaAbstract: Poly(propylene adipate-block-poly(ε-caprolactone copolymers were synthesized using a combination of polycondensation and ring-opening polymerization of ε-caprolactone in the presence of poly(propylene adipate. Gel permeation chromatography was used for molecular weight determination, whereas hydrogen-1 nuclear magnetic resonance and carbon-13 nuclear magnetic resonance spectroscopy were employed for copolymer characterization and composition evaluation. The copolymers were found to be block while their composition was similar to the feeding ratio. They formed semicrystalline structures, while only poly(ε-caprolactone formed crystals, as shown by wide angle X-ray diffraction. Differential scanning calorimetry data suggest that the melting point and heat of fusion of copolymers decreased by increasing the poly(propylene adipate amount. The synthesized polymers exhibited low cytotoxicity and were used to encapsulate desferrioxamine, an iron-chelating drug. The desferrioxamine nanoparticles were self-assembled into core shell structures, had mean particle size <250 nm, and the drug remained in crystalline form. Further studies revealed that the dissolution rate was mainly related to the melting temperature, as well as to the degree of crystallinity of copolymers.Keywords: biocompatible polyesters, poly(ε-caprolactone, poly(propylene adipate, drug encapsulation, desferrioxamine

  17. Label-free immunosensor based on one-step electrodeposition of chitosan-gold nanoparticles biocompatible film on Au microelectrode for determination of aflatoxin B1 in maize.

    Science.gov (United States)

    Ma, Haihua; Sun, Jizhou; Zhang, Yuan; Bian, Chao; Xia, Shanhong; Zhen, Tong

    2016-06-15

    Gold nanoparticles (AuNPs) embedded in chitosan (CHI) film, well-dispersed and smaller in size (about 10 nm), were fabricated by one-step electrodeposion on Au microelectrode in solution containing chitosan and chloride trihydrate. The nano-structure CHI-AuNPs composite film offers abundant amine groups, good conductivity, excellent biocompatibility and stability for antibody immobilization. The combination of aflatoxin B1 (AFB1) with immobilized antibody introduces a barrier to electron transfer, resulting in current decreasement. The morphologies and characterizations of modified microelectrodes were investigated by scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). The proposed non-enzyme and label-free immunosensor exhibited high sensitive amperometric response to AFB1 concentration in two linear ranges of 0.1 to 1 ng mL(-1) and 1 to 30 ng mL(-1), with the detection limit of 0.06 ng mL(-1) (S/N=3). The immunoassay was also applied for analysis of maize samples spiked with AFB1. Considering the sample extraction procedure, the linear range and limit of detection were assessed to be 1.6-16 ng mL(-1) and 0.19 ng mL(-1) respectively. The simple method showed good fabrication controllability and reproducibility for immunosensor design. PMID:26851579

  18. CLAVATA3 dodecapeptide modified CdTe nanoparticles: a biocompatible quantum dot probe for in vivo labeling of plant stem cells.

    Directory of Open Access Journals (Sweden)

    Guanghui Yu

    Full Text Available CLAVATA3 (CLV3 dodecapeptides function in plant stem cell maintenance, but CLV3 function in cell-cell communication remains less clear. Here, we coupled CLV3 dodecapeptides to synthesized CdTe nanoparticles to track their bioactivity on stem cells in the root apical meristem. To achieve this, we first synthesized CdTe quantum dots (QDs using a one-pot method, and then evaluated the cytotoxicity of the QDs in BY-2 cells. The results showed that QDs in plant cells must be used at low concentrations and for short treatment time. To make biocompatible probes to track stem cell fate, we conjugated CLV3 dodecapeptides to the QDs by the zero-coupling method; this modification greatly reduced the cytotoxicity of the QDs. Furthermore, we detected CLV3-QDs localized on the cell membrane, consistent with the known localization of CLV3. Our results indicate that using surface-modified QDs at low concentrations and for short time treatment can improve their utility for plant cell imaging.

  19. Bare and protein-conjugated Fe3O4 ferromagnetic nanoparticles for utilization in magnetically assisted hemodialysis: biocompatibility with human blood cells

    Science.gov (United States)

    Stamopoulos, D.; Manios, E.; Gogola, V.; Benaki, D.; Bouziotis, P.; Niarchos, D.; Pissas, M.

    2008-12-01

    Magnetically assisted hemodialysis is a development of conventional hemodialysis and is based on the circulation of ferromagnetic nanoparticle-targeted binding substance conjugates (FN-TBS Cs) in the bloodstream of the patient and their eventual removal by means of a 'magnetic dialyzer'. Presented here is an in vitro investigation on the biocompatibility of bare Fe3O4 FNs and Fe3O4-bovine serum albumin Cs with blood cells, namely red blood cells (RBCs), white blood cells (WBCs) and platelets (Plts). Atomic force microscopy (AFM) and optical microscopy (OM) enabled the examination of blood cells at the nanometer and micrometer level, respectively. The observations made on FN- and C-maturated blood samples are contrasted to those obtained on FN- and C-free reference blood samples subjected to exactly the same maturation procedure. Qualitatively, both AFM and OM revealed no changes in the overall shape of RBCs, WBCs and Plts. Incidents where bare FNs or Cs were bound onto the surface of RBCs or internalized by WBCs were very rare. Detailed examination by means of OM proved that impaired coagulation of Plts is not initiated/promoted either by FNs or Cs. Quantitatively, the statistical analysis of the obtained AFM images from RBC surfaces clearly revealed that the mean surface roughness of RBCs maturated with bare FNs or Cs was identical to the one of reference RBCs.

  20. Fine tuning of magnetite nanoparticle size distribution using dissymmetric potential pulses in the presence of biocompatible surfactants and the electrochemical characterization of the nanoparticles.

    Science.gov (United States)

    Rodríguez-López, A; Cruz-Rivera, J J; Elías-Alfaro, C G; Betancourt, I; Ruiz-Silva, H; Antaño-López, R

    2015-01-01

    The effects of varying the surfactant concentration and the anodic pulse potential on the properties and electrochemical behaviors of magnetite nanoparticles were investigated. The nanoparticles were synthesized with an electrochemical method based on applying dissymmetric potential pulses, which offers the advantage that can be used to tune the particle size distribution very precisely in the range of 10 to 50 nm. Under the conditions studied, the surfactant concentration directly affects the size distribution, with higher concentrations producing narrower distributions. Linear voltammetry was used to characterize the electrochemical behavior of the synthesized nanoparticles in both the anodic and cathodic regions, which are attributed to the oxidation of Fe(2+) and the reduction of Fe(3+); these species are part of the spinel structure of magnetite. Electrochemical impedance spectroscopy data indicated that the reduction and oxidation reactions of the nanoparticles are not controlled by the mass transport step, but by the charge transfer step. The sample with the highest saturation magnetization was that synthesized in the presence of polyethylene glycol.

  1. Biocompatible hybrid nanomaterials involving polymers and hydrogels interfaced with phosphorescent complexes and toxin-free metallic nanoparticles for biomedical applications

    Science.gov (United States)

    Marpu, Sreekar B.

    The major topics discussed are all relevant to interfacing brightly phosphorescent and non-luminescent coinage metal complexes of [Ag(I) and Au(I)] with biopolymers and thermoresponsive gels for making hybrid nanomaterials with an explanation on syntheses, characterization and their significance in biomedical fields. Experimental results and ongoing work on determining outreaching consequences of these hybrid nanomaterials for various biomedical applications like cancer therapy, bio-imaging and antibacterial abilities are described. In vitro and in vivo studies have been performed on majority of the discussed hybrid nanomaterials and determined that the cytotoxicity or antibacterial activity are comparatively superior when compared to analogues in literature. Consequential differences are noticed in photoluminescence enhancement from hybrid phosphorescent hydrogels, phosphorescent complex ability to physically crosslink, Au(I) sulfides tendency to form NIR (near-infrared) absorbing AuNPs compared to any similar work in literature. Syntheses of these hybrid nanomaterials has been thoroughly investigated and it is determined that either metallic nanoparticles syntheses or syntheses of phosphorescent hydrogels can be carried in single step without involving any hazardous reducing agents or crosslinkers or stabilizers that are commonly employed during multiple step syntheses protocols for syntheses of similar materials in literature. These astounding results that have been discovered within studies of hybrid nanomaterials are an asset to applications ranging from materials development to health science and will have striking effect on environmental and green chemistry approaches.

  2. In vivo Biocompatibility, Biodistribution and Therapeutic Efficiency of Titania Coated Upconversion Nanoparticles for Photodynamic Therapy of Solid Oral Cancers.

    Science.gov (United States)

    Lucky, Sasidharan Swarnalatha; Idris, Niagara Muhammad; Huang, Kai; Kim, Jaejung; Li, Zhengquan; Thong, Patricia Soo Ping; Xu, Rong; Soo, Khee Chee; Zhang, Yong

    2016-01-01

    Despite the advantages of using photodynamic therapy (PDT) for the treatment of head and neck tumors, it can only be used to treat early stage flat lesions due to the limited tissue penetration ability of the visible light. Here, we developed near-infrared (NIR) excitable upconversion nanoparticle (UCN) based PDT agent that can specifically target epithelial growth factor receptor (EGFR) overexpressing oral cancer cells, in a bid to widen the application of PDT against thick and solid advanced or recurrent head and neck cancers. In vivo studies using the synthesized anti-EGFR-PEG-TiO2-UCNs following systemic administration displayed no major sub-acute or long term toxic effects in terms of blood biochemical, hematological or histopathological changes at a concentration of 50 mg/kg. NIR-PDT even in the presence of a 10 mm tissue phantom placed over the xenograft tumor, showed significant delay in tumor growth and improved survival rate compared to conventional chlorin-e6 (Ce6) PDT using 665 nm red light. Our work, one of the longest study till date in terms of safety (120 d), PDT efficacy (35 d) and survival (60 d), demonstrates the usefulness of UCN based PDT technology for targeted treatment of thick and bulky head and neck tumors.

  3. Green and ecofriendly synthesis of silver nanoparticles: Characterization, biocompatibility studies and gel formulation for treatment of infections in burns.

    Science.gov (United States)

    Jadhav, Kiran; Dhamecha, Dinesh; Bhattacharya, Debdutta; Patil, Mrityunjaya

    2016-02-01

    The current study summarizes a unique green process for the synthesis of silver nanoparticles (AgNPs) by simple treatment of silver nitrate with aqueous extract of Ammania baccifera. Phytosynthesized AgNPs were characterized by various advanced analytical methods and studied for its use against infections associated with burns. Formation of AgNPs was observed by visual color change from colorless to dark brown and confirmed by UV-visible characteristic peak at 436 nm. Zeta potential, particle size and polydispersity index of nano-silver were found to be -33.1 ± 1.12, 112.6 ± 6.8 nm and 0.3 ± 0.06 respectively. XRD spectra revealed crystalline nature of AgNPs whereas TEM confirmed the presence of mixed morphology of AgNPs. The overall approach designated in the present research investigation for the synthesis of AgNPs is based on all 12 principles of green chemistry, in which no man-made chemical other than the silver nitrate was used. Synthesized nano-silver colloidal dispersion was initially tested for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against a panel of organisms involved in infections associated with burns (Pseudomonas aeruginosa (PA), Staphylococcus aureus (SA) and methicillin resistant S. aureus (MRSA)). MIC and MBC were found to be in range of 0.992 to 7.93 and 7.93 to 31.75 μg/mL respectively. MBC was used for formulation of AgNP gel and tested for its efficacy using agar well diffusion method against PA, SA and MRSA. Comparative bactericidal efficacy of formulated gel (0.03% w/w) and marked formulation Silverex™ ionic (silver nitrate gel 0.2% w/w) showed equal zone of inhibition against all pathogenic bacteria. Formulated AgNP gel consisting of 95% lesser concentration of silver compared to marketed formulation was found to be equally effective against all organisms. Hence, the formulated AgNP gel could serve as a better alternative with least toxicity towards the treatment presently available for

  4. Determining the 3D orientation of optically trapped upconverting nanorods by in situ single-particle polarized spectroscopy

    Science.gov (United States)

    Rodríguez-Sevilla, Paloma; Labrador-Páez, Lucía; Wawrzyńczyk, Dominika; Nyk, Marcin; Samoć, Marek; Kar, Ajoy Kumar; MacKenzie, Mark D.; Paterson, Lynn; Jaque, Daniel; Haro-González, Patricia

    2015-12-01

    An approach to unequivocally determine the three-dimensional orientation of optically manipulated NaYF4:Er3+,Yb3+ upconverting nanorods (UCNRs) is demonstrated. Long-term immobilization of individual UCNRs inside single and multiple resonant optical traps allow for stable single UCNR spectroscopy studies. Based on the strong polarization dependent upconverted luminescence of UCNRs it is possible to unequivocally determine, in real time, their three-dimensional orientation when optically trapped. In single-beam traps, polarized single particle spectroscopy has concluded that UCNRs orientate parallel to the propagation axis of the trapping beam. On the other hand, when multiple-beam optical tweezers are used, single particle polarization spectroscopy demonstrated how full spatial control over UCNR orientation can be achieved by changing the trap-to-trap distance as well as the relative orientation between optical traps. All these results show the possibility of real time three-dimensional manipulation and tracking of anisotropic nanoparticles with wide potential application in modern nanobiophotonics.An approach to unequivocally determine the three-dimensional orientation of optically manipulated NaYF4:Er3+,Yb3+ upconverting nanorods (UCNRs) is demonstrated. Long-term immobilization of individual UCNRs inside single and multiple resonant optical traps allow for stable single UCNR spectroscopy studies. Based on the strong polarization dependent upconverted luminescence of UCNRs it is possible to unequivocally determine, in real time, their three-dimensional orientation when optically trapped. In single-beam traps, polarized single particle spectroscopy has concluded that UCNRs orientate parallel to the propagation axis of the trapping beam. On the other hand, when multiple-beam optical tweezers are used, single particle polarization spectroscopy demonstrated how full spatial control over UCNR orientation can be achieved by changing the trap-to-trap distance as well as

  5. Upconverting PAAm/PNIPAM/NaYF{sub 4}:Yb:Er hydrogel with enhanced luminescence temperature sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jiachang; He, Benzhao; Cheng, Zehong; Zhou, Li, E-mail: zhouli@glut.edu.cn

    2015-04-15

    We present a one-step approach to combine the functional features of upconverting NaYF{sub 4}:Yb:Er nanoparticles and thermosensitive poly(N-isopropylacrylamide) (PNIPAM) for luminescence thermometry. Dual-functional hydrogel that simultaneously possesses strong upconversion luminescence (UL) and temperature responsibility was fabricated based on the crosslinking of poly(acrylamide) in the presence of PNIPAM and NaYF{sub 4}:Yb:Er nanoparticles. The obtained hydrogel exhibited reversibly temperature-dependent UL and highly enhanced sensibility. The luminescence temperature sensitivity reached 1.9% per °C and 0.7% per °C in the range of 27–33 °C and 35–45 °C, respectively. The maximum sensitivity could even reach 26.5% per °C in the range of 33–35 °C. Considering the facile fabrication process and fine luminescence thermometry performance, this study thus opens up new opportunities for preparing highly sensitive temperature sensors. - Highlights: • One-step fabrication of upconverting and thermosensitve PAAm/PNIPAM/NaYF{sub 4}:Yb:Er hydrogel is reported. • The combination of functional features of NaYF{sub 4}:Yb:Er upconversion nanoparticles (UCNPs) and thermosensitve PNIPAM can efficiently enhance the luminescence temperature sensitivity of UCNPs. • The luminescence temperature sensitivity of hydrogel can respectively reach 1.9% per °C and 0.7% per °C in the range of 27–33 °C and 35–45 °C. • The maximum sensitivity can even reach 26.5% per °C in range of 33–35 °C.

  6. One-pot synthesis of biocompatible boronic acid-functionalized poly(methyl methacrylate) nanoparticles at sub-100 nm scale for glucose sensing

    Energy Technology Data Exchange (ETDEWEB)

    Sakalak, Huseyin [Selcuk University, Metallurgy and Materials Engineering (Turkey); Ulasan, Mehmet; Yavuz, Emine [Selcuk University, Advanced Technology Research and Application Center (Turkey); Camli, Sevket Tolga, E-mail: tolgacamli@gmail.com [Biyotez Machinery Chemistry R& D Co. Ltd. (Turkey); Yavuz, Mustafa Selman, E-mail: selmanyavuz@selcuk.edu.tr [Selcuk University, Metallurgy and Materials Engineering (Turkey)

    2014-12-15

    Poly(methyl methacrylate) nanoparticles containing 4-vinylphenyl boronic acid were synthesized in one pot by surfactant-free emulsion polymerization. The nanoparticles were characterized by scanning electron microscopy and dynamic light scattering. Boron content in the nanoparticles was confirmed by electron-dispersive X-ray spectroscopy. In polymerization process, several co-monomer ratios were studied in order to obtain optimum nanoparticle size. Average hydrodynamic diameter and polydispersity index of nanoparticles versus variation of acetone percentage in the solvent mixture and total monomer concentration were investigated. The effect of boronic acid concentration in the monomer mixture on nanoparticle size and size distribution was also reported. Without further functionalization to the nanoparticles, the catechol dye, alizarin red S, was bound to boronic acid-containing nanoparticles. These nanoparticles behave as a nanosensor by which glucose or fructose can be easily detected. Dye-containing nanoparticles were undertaken displacement reaction by glucose or fructose. The glucose or fructose content was also monitored by UV–Visible spectrophotometer. Furthermore, cytotoxicity studies of boronic acid-carrying poly(methyl methacrylate) nanoparticles were carried out in 3T3 cells, which showed no toxicity effect on the cells.

  7. Multiphoton up-converting phosphors for use in rapid immunoassays

    Science.gov (United States)

    Niedbala, R. Sam; Vail, Timothy L.; Feindt, Hans; Li, S.; Burton, Jarrett L.

    2000-04-01

    There exists increasing demand for rapid in-vitro diagnostic test capable of detecting pathogens, disease markers, and drugs. Many currently marketed technologies are limiting due to their analytical sensitivity or the number of analytes detected in a single assay. Presented is the use of up- converting phosphors as reporters in rapid point-of-care diagnostic assays using a lateral flow format in a nitrocellulose matrix. Up-converting Phosphor Technology (UPT) utilizes lanthanide-doped ceramic particles that possess anti-Stokes shift emission. These material absorb multiple IR photons and emit dopant-dependent spectra in the visible range. Their signature spectra allow the development of sensitive, multi-analyte diagnostic test. Because no biological matrix up-converts in the IR, the sensitivity of the assay is enhanced, being determined by the affinity of the biological constituents and the level of non-specific binding of the particle reporter. Feasibility data presented below represent a wide range of molecular weight analytes, including drugs of abuse, proteins such as cardiac markers, and pathogenic microorganisms.

  8. A new biosensor for glucose determination in serum based on up-converting fluorescence resonance energy transfer.

    Science.gov (United States)

    Peng, Jianhong; Wang, Yuhui; Wang, Jialan; Zhou, Xin; Liu, Zhihong

    2011-10-15

    In this work, a new glucose sensor based on up-converting fluorescence resonance energy transfer (UC-FRET) was developed. Up-converting phosphors (UCPs, NaYF(4): Yb, Er), which were covalently labeled with Concanavalin A (ConA), were used as the energy donor with thiolated β-cyclodextrins (SH-β-CDs) functionalized gold nanoparticles as the energy acceptor. Due to the combination between ConA and SH-β-CDs, the energy donor and the acceptor were brought to close proximity, resulting in the quenching of the fluorescence of UCPs by gold nanoparticles. In the presence of glucose which competed with SH-β-CDs towards the binding sites of ConA, the biosensor (UCPs-ConA-SH-β-CDs-Au) was decomposed and the energy donor was separated from the acceptor. Therefore, the fluorescence of UCPs was restored dependent on the concentration of glucose. The increase of UCPs fluorescence intensity was proportional to glucose concentration within the range from 0.4 μM to 10μM in aqueous buffer, with a limit of detection (LOD) of 0.043 μM. A same linear range of glucose concentration was obtained in a human serum matrix (which was pretreated and thus contained no glucose) with a slightly higher LOD (0.065 μM). The glucose sensor was applied to real human serum samples with the results consistent with that of a classic hexokinase (HK) method, indicating that the UC-FRET biosensor was competent for directly sensing glucose in serum samples without optical interference, which benefited from the near infrared (NIR) excitation nature of UCPs. The results of this work suggested that the UC-FRET technique could be a promising alternative for detecting biomolecules in complex biological sample matrixes for diagnostic purposes. PMID:21852101

  9. Terbium doped SnO2 nanoparticles as white emitters and SnO2:5Tb/Fe3O4 magnetic luminescent nanohybrids for hyperthermia application and biocompatibility with HeLa cancer cells.

    Science.gov (United States)

    Singh, Laishram Priyobarta; Singh, Ningthoujam Premananda; Srivastava, Sri Krishna

    2015-04-14

    SnO2:5Tb (SnO2 doped with 5 at% Tb(3+)) nanoparticles were synthesised by a polyol method and their luminescence properties at different annealing temperatures were studied. Characterization of nanomaterials was done by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). XRD studies indicate that the prepared nanoparticles were of tetragonal structures. Upon Tb(3+) ion incorporation into SnO2, Sn(4+) changes to Sn(2+) and, on annealing again at higher temperature, Sn(2+) changes to Sn(4+). The prepared nanoparticles were spherical in shape. Sn-O vibrations were found from the FTIR studies. In photoluminescence studies, the intensity of the emission peaks of Tb(3+) ions increases with the increase of annealing temperature, and emission spectra lie in the region of white emission in the CIE diagram. CCT calculations show that the SnO2:5Tb emission lies in cold white emission. Quantum yields up to 38% can be obtained for 900 °C annealed samples. SnO2:5Tb nanoparticles were well incorporated into the PVA polymer and such a material incorporated into the polymer can be used for display devices. The SnO2:5Tb/Fe3O4 nanohybrid was prepared and investigated for hyperthermia applications at different concentrations of the nanohybrid. This achieves a hyperthermia temperature (42 °C) under an AC magnetic field. The hybrid nanomaterial SnO2:5Tb/Fe3O4 was found to exhibit biocompatibility with HeLa cells (human cervical cancer cells) at concentrations up to 74% for 100 μg L(-1). Also, this nanohybrid shows green emission and thus it will be helpful in tracing magnetic nanoparticles through optical imaging in vivo and in vitro application. PMID:25747103

  10. Cathodic-controlled and near-infrared organic upconverter for local blood vessels mapping

    Science.gov (United States)

    Yuan, Chih-Hsien; Lee, Chih-Chien; Liu, Chun-Fu; Lin, Yun-Hsuan; Su, Wei-Cheng; Lin, Shao-Yu; Chen, Kuan-Ting; Li, Yan-De; Chang, Wen-Chang; Li, Ya-Ze; Su, Tsung-Hao; Liu, Yu-Hsuan; Liu, Shun-Wei

    2016-08-01

    Organic materials are used in novel optoelectronic devices because of the ease and high compatibility of their fabrication processes. Here, we demonstrate a low-driving-voltage cathodic-controlled organic upconverter with a mapping application that converts near-infrared images to produce images of visible blood vessels. The proposed upconverter has a multilayer structure consisting of a photosensitive charge-generation layer (CGL) and a phosphorescent organic light-emitting diode (OLED) for producing clear images with a high resolution of 600 dots per inch. In this study, temperature-dependent electrical characterization was performed to analyze the interfacial modification of the cathodic-controlled upconverter. The result shows that the upconverter demonstrated a high conversion efficiency of 3.46% because of reduction in the injection barrier height at the interface between the CGL and the OLED.

  11. Femtosecond upconverted photocurrent spectroscopy of InAs quantum nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Yasuhiro [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Tex, David M.; Kanemitsu, Yoshihiko, E-mail: kanemitu@scl.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Japan Science and Technology Agency, CREST, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kamiya, Itaru [Toyota Technological Institute, Nagoya, Aichi 468-8511 (Japan)

    2015-07-06

    The carrier upconversion dynamics in InAs quantum nanostructures are studied for intermediate-band solar-cell applications via ultrafast photoluminescence and photocurrent (PC) spectroscopy based on femtosecond excitation correlation (FEC) techniques. Strong upconverted PC-FEC signals are observed under resonant excitation of quantum well islands (QWIs), which are a few monolayer-thick InAs quantum nanostructures. The PC-FEC signal typically decays within a few hundred picoseconds at room temperature, which corresponds to the carrier lifetime in QWIs. The photoexcited electron and hole lifetimes in InAs QWIs are evaluated as functions of temperature and laser fluence. Our results provide solid evidence for electron–hole–hole Auger process, dominating the carrier upconversion in InAs QWIs at room temperature.

  12. Simultaneous synthesis and functionalization of water-soluble up-conversion nanoparticles for in-vitro cell and nude mouse imaging

    Science.gov (United States)

    Wang, Zhen-Ling; Hao, Jianhua; Chan, Helen L. W.; Law, Ga-Lai; Wong, Wing-Tak; Wong, Ka-Leung; Murphy, Margaret B.; Su, T.; Zhang, Z. H.; Zeng, S. Q.

    2011-05-01

    Water-solubility and biocompatibility are prerequisites for rare-earth up-converting nanophosphors applied to biological imaging. In this work, we have developed a facile and one-step synthesis technique, through which water-soluble NaYF4: Yb3+, Er3+ nanoparticles (NPs) with functional groups including 3-mercaptopropionic acid, 6-aminocaproic acid and poly(ethylene glycol)methyl ether on their surface can be directly prepared without any further surface treatment. Some inorganic salts will be selected as starting materials, water and some low toxic organic agents have been used as reaction media, which differs from earlier works. Structural and up-converting fluorescence are characterized by a variety of techniques. Cell uptake and in-vitro imaging of the as-synthesized NPs have been investigated using a multiphoton con-focal laser scanning microscope with a near-infrared excitation source. Internalization of the bare and functionalized NPs in human lung carcinoma A549 and human cervical carcinoma HeLa cells are studied at a nanoparticle loading of 10 µg mL-1 over an exposure period from 30 min to 24 h. The cytotoxicity of modified NPs in HeLa cells is found to be low. In addition, the feasibility of the NPs in animal imaging has been demonstrated by subcutaneously injecting these NPs into nude mouse. The results indicated that our directly synthesized NPs coated with various functional groups are promising as bio-imaging agents due to their easy uptake, long lasting, low cytotoxicity, emissive in various human carcinoma cell lines and small animals through up-conversion with near-infrared excitation.

  13. A biocompatible magnetic film: synthesis and characterization

    Science.gov (United States)

    Chatterjee, Jhunu; Haik, Yousef; Chen, Ching Jen

    2004-01-01

    Background Biotechnology applications of magnetic gels include biosensors, targeted drug delivery, artificial muscles and magnetic buckles. These gels are produced by incorporating magnetic materials in the polymer composites. Methods A biocompatible magnetic gel film has been synthesized using polyvinyl alcohol. The magnetic gel was dried to generate a biocompatible magnetic film. Nanosized iron oxide particles (γ-Fe2O3, ~7 nm) have been used to produce the magnetic gel. Results The surface morphology and magnetic properties of the gel films were studied. The iron oxide particles are superparamagnetic and the gel film also showed superparamagnetic behavior. Conclusion Magnetic gel made out of crosslinked magnetic nanoparticles in the polymer network was found to be stable and possess the magnetic properties of the nanoparticles. PMID:14761251

  14. Inulin as a novel biocompatible coating: evaluation of surface affinities toward CaHPO4, α-Fe2O3, ZnO, CaHPO4@ZnO and α-Fe2O3@ZnO nanoparticles.

    Science.gov (United States)

    Santillán-Urquiza, E; Arteaga-Cardona, F; Hernandez-Herman, E; Pacheco-García, P F; González-Rodríguez, R; Coffer, J L; Mendoza-Alvarez, M E; Vélez-Ruiz, J F; Méndez-Rojas, M A

    2015-12-15

    The introduction of biocompatible coatings onto nanoparticle surfaces can be synthetically challenging. In this work, calcium phosphate (brushite, CaHPO4⋅2H2O), iron oxide (hematite, α-Fe2O3), zinc oxide (ZnO), and CaHPO4@ZnO and α-Fe2O3@ZnO nanoparticles were synthesized and treated with the biocompatible, biodegradable, polysaccharide inulin {(2R,3S,4S,5R)-2-[[(2R,3S,4S,5R)-3,4-dihydroxy-2,5-bis(hydroxymethyl)oxolan-2-yl]oxymethyl]-5-(hydroxymethyl)oxolane-2,3,4-triol} under mild conditions. The products were fully characterized by Fourier transforms infrared (FTIR) spectroscopy, energy dispersive spectroscopy (EDS), dynamic light scattering (DLS), differential thermogravimetric/differential thermal analysis (TGA/DTA), transmission electron microscopy (TEM) and powder X-ray diffraction (XRD). Surface interactions among hematite and brushite with inulin are weak, but coating the nanoparticle surface with ZnO increased the affinity toward the polysaccharide. Inulin adsorption on the nanoparticle surface was confirmed by thermal and spectroscopic analyses. The nanoparticles had diameters ranging from 50 to 80nm, with nearly spherical morphology. The nanoparticles sizes, stability and solubility in water could make them useful as components for enriched foods.

  15. One-step synthesis of highly-biocompatible spherical gold nanoparticles using [i]Artocarpus heterophyllus[/i] Lam. (jackfruit) fruit extract and its effect on pathogens

    OpenAIRE

    Nagaraj Basavegowda; Gowri Dhanya Kumar; Bozena Tyliszczak; Zbigniew Wzorek; Agnieszka Sobczak-Kupiec

    2015-01-01

    [b]Introduction[/b]. Novel approaches for the synthesis of gold nanoparticles (AuNPs) are of great importance due to its vast spectrum of applications in diverse fields, including medical diagnostics and therapeutics. Te presented study reports the successful AuNPs’ synthesis using [i]Artocarpus heterophyllus[/i] Lam. extract, and provides detailed characterization and evaluation of its antibacterial potential. [b]Objective[/b]. The aim was to develop a cost-effective and environmentall...

  16. One-step synthesis of highly-biocompatible spherical gold nanoparticles using [i]Artocarpus heterophyllus[/i] Lam. (jackfruit fruit extract and its effect on pathogens

    Directory of Open Access Journals (Sweden)

    Nagaraj Basavegowda

    2015-02-01

    Full Text Available [b]Introduction[/b]. Novel approaches for the synthesis of gold nanoparticles (AuNPs are of great importance due to its vast spectrum of applications in diverse fields, including medical diagnostics and therapeutics. Te presented study reports the successful AuNPs’ synthesis using [i]Artocarpus heterophyllus[/i] Lam. extract, and provides detailed characterization and evaluation of its antibacterial potential. [b]Objective[/b]. The aim was to develop a cost-effective and environmentally friendly synthesis method of gold nanoparticles using aqueous fruit extract of [i]Artocarpus heterophyllus[/i] Lam. as a reducing and capping agent, which has proven activity against human pathogens, such as microbial species [i]E.coli[/i] and [i]Streptobacillus[/i] sps. [b]Materials and method[/b]. Characterizations were carried out using ultraviolet-visible (UV-Vis spectrophotometry, scanning electron microscopy (SEM, energy dispersive X-ray and Fourier-Transform infra-red spectroscopy (FT-IR. [b]Results[/b]. SEM images showed the formation of gold nanoparticles with an average size of 20–25 nm. Spectra collected while infra-red analysis contained broad peaks in ranges from 4000–400 cm -1 . [b]Conclusions[/b]. It can be concluded that the fruit of [i]Artocarpus heterophyllus[/i] Lam. can be good source for synthesis of gold nanoparticles which showed antimicrobial activity against investigated microbes, in particul [i]E. coli[/i], and [i]Streptobacillus[/i]. An important outcome of this study will be the development of value-added products from the medicinal plant [i]Artocarpus heterophyllus[/i] Lam. for the biomedical and nanotechnology-based industries.

  17. Optical property measurements of a novel type of upconverting reporter

    Science.gov (United States)

    Xiao, Xudong; Herring, Michael E.; Haushalter, Jeanne; Lee, Seonkyung; Kalogerakis, Kostas S.; Faris, Gregory W.

    2003-07-01

    We have recently developed a new type of reporter (upconverting chelate) for biomedical diagnostics. For this reporter, the light is absorbed and emitted by a lanthanide ion, rather than an organic molecule, as is the case for a typical fluorescent dye. These materials do not photobleach and have no autofluorescent background. We focus in this paper on neodymium ions complexed with the familiar chelating agents, EDTA, DPA, DTPA and DOTA. We have performed experimental measurements with one- and two-color laser light excitation for different chelate compounds. The samples are excited using two Nd:YAG-pumped dye laser systems that provide laser light near 587 nm and 800 nm. For one-color excitation, the emitted light depends quadratically on the incident laser power, as expected. Three strongly emitting lines are observed, located near 360 nm, 387 nm, and 417 nm. We observed more efficient upconversion in EDTA although the DPA chelates show comparable ground state absorbance. We have studied the influence of temporal delay between the two laser pulses and obtained the decay lifetime of the first intermediate state in the various chelated compounds.

  18. Compact upconverting phosphor detection system for wick assays

    Science.gov (United States)

    Riris, Haris; Van der Laan, Jan E.; Cooper, David E.; Nashold, Karen M.; Carlisle, Clinton B.; Schneider, Luke V.

    1997-05-01

    We describe an integrated detection system based on upconverting phosphor particles bound to capture sites on the inside surfaces of rectangular wick capillaries. This deice can be used with either antibody or nucleic acid to detect specific micro-organisms. The system uses a high- power, 980 nm, semiconductor diode laser to illuminate 200 X 300 X 20 micrometers capture surfaces. The rectangular capillary wicks are held in a tray that is inserted into the detection system, positioning the capture surface at the object plane of the optical system. Phosphorescent light emitted from the capture surface is collected by a high numerical aperture microscope objective and directed through a series of filters onto either a CCD camera or a photomultiplier. A combination of band-reject filters attenuates the 980 nm laser excitation light and its harmonic at 490 nm, and a tunable liquid crystal filter provides for rapid scanning from 400 to 750 nm. The data acquisition and control is controlled by a laptop PC with a custom GUI interface developed using LabWindows/CVI. The system can detect a single phosphor particle bound to a capture surface.

  19. Antibacterial activity and biocompatibility of three-dimensional nanostructured porous granules of hydroxyapatite and zinc oxide nanoparticles--an in vitro and in vivo study.

    Science.gov (United States)

    Grenho, L; Salgado, C L; Fernandes, M H; Monteiro, F J; Ferraz, M P

    2015-08-01

    Ceramic scaffolds are widely studied in the bone tissue engineering field due to their potential in regenerative medicine. However, adhesion of microorganisms on biomaterials with subsequent formation of antibiotic-resistant biofilms is a critical factor in implant-related infections. Therefore, new strategies are needed to address this problem. In the present study, three-dimensional and interconnected porous granules of nanostructured hydroxyapatite (nanoHA) incorporated with different amounts of zinc oxide (ZnO) nanoparticles were produced using a simple polymer sponge replication method. As in vitro experiments, granules were exposed to Staphylococcus aureus and Staphylococcus epidermidis and, after 24 h, the planktonic and sessile populations were assessed. Cytocompatibility towards osteoblast-like cells (MG63 cell line) was also evaluated for a period of 1 and 3 days, through resazurin assay and imaging flow cytometry analysis. As in vivo experiments, nanoHA porous granules with and without ZnO nanoparticles were implanted into the subcutaneous tissue in rats and their inflammatory response after 3, 7 and 30 days was examined, as well as their antibacterial activity after 1 and 3 days of S. aureus inoculation. The developed composites proved to be especially effective at reducing bacterial activity in vitro and in vivo for a weight percentage of 2% ZnO, with a low cell growth inhibition in vitro and no differences in the connective tissue growth and inflammatory response in vivo. Altogether, these results suggest that nanoHA-ZnO porous granules have a great potential to be used in orthopaedic and dental applications as a template for bone regeneration and, simultaneously, to restrain biomaterial-associated infections. PMID:26180062

  20. Antibacterial activity and biocompatibility of three-dimensional nanostructured porous granules of hydroxyapatite and zinc oxide nanoparticles--an in vitro and in vivo study.

    Science.gov (United States)

    Grenho, L; Salgado, C L; Fernandes, M H; Monteiro, F J; Ferraz, M P

    2015-08-01

    Ceramic scaffolds are widely studied in the bone tissue engineering field due to their potential in regenerative medicine. However, adhesion of microorganisms on biomaterials with subsequent formation of antibiotic-resistant biofilms is a critical factor in implant-related infections. Therefore, new strategies are needed to address this problem. In the present study, three-dimensional and interconnected porous granules of nanostructured hydroxyapatite (nanoHA) incorporated with different amounts of zinc oxide (ZnO) nanoparticles were produced using a simple polymer sponge replication method. As in vitro experiments, granules were exposed to Staphylococcus aureus and Staphylococcus epidermidis and, after 24 h, the planktonic and sessile populations were assessed. Cytocompatibility towards osteoblast-like cells (MG63 cell line) was also evaluated for a period of 1 and 3 days, through resazurin assay and imaging flow cytometry analysis. As in vivo experiments, nanoHA porous granules with and without ZnO nanoparticles were implanted into the subcutaneous tissue in rats and their inflammatory response after 3, 7 and 30 days was examined, as well as their antibacterial activity after 1 and 3 days of S. aureus inoculation. The developed composites proved to be especially effective at reducing bacterial activity in vitro and in vivo for a weight percentage of 2% ZnO, with a low cell growth inhibition in vitro and no differences in the connective tissue growth and inflammatory response in vivo. Altogether, these results suggest that nanoHA-ZnO porous granules have a great potential to be used in orthopaedic and dental applications as a template for bone regeneration and, simultaneously, to restrain biomaterial-associated infections.

  1. β-cyclodextrin functionalized poly (5-amidoisophthalicacid) grafted Fe3O4 magnetic nanoparticles: A novel biocompatible nanocomposite for targeted docetaxel delivery

    Science.gov (United States)

    Tarasi, Roghayeh; Khoobi, Mehdi; Niknejad, Hassan; Ramazani, Ali; Ma'mani, Leila; Bahadorikhalili, Saeed; Shafiee, Abbas

    2016-11-01

    Thiol-lactam initiated radical polymerization (TLIRP) was successfully employed to prepare poly-N-5-acrylamidoisophthalicacid grafted onto Fe3O4 magnetic nanoparticles (MNPs@PAIP). β-Cyclodextrin (CD) was then conjugated to the carboxylic groups of the prepared MNPs via carbodiimide activation. Subsequently, tumor-targeting folic acid (FA) was attached to the hydroxyl groups of CD on the surface of the latter MNPs to increase the site-specific intracellular delivery. The prepared MNPs were fully characterized by FTIR, VSM, TGA, XRD, FE-SEM and TEM. Docetaxel (DTX) as hydrophobic anticancer drug was loaded via host-guest inclusion complexation with CD and the release profile of the system was studied at different pH. The effect of MNPs on the cell viability was evaluated for the human embryonic kidney normal cell line (HEK293) as well as HeLa and MDA-MB-231 cancerous cell lines and the results did not show any apparent cytotoxic effect. In comparison, DTX loaded MNPs reduced the growth of HeLa and MDA-MB-231 cells more than free DTX. Intracellular uptake ability of DTX loaded MNPs was also studied using fluorescent microscopy and showed cellular uptake about 90% after 4 h treatment.

  2. Biocompatibility of Dental Amalgams

    OpenAIRE

    Yurdanur Uçar; Brantley, William A.

    2011-01-01

    Objective. The purpose of this review paper is to review the literature regarding the toxicology of mercury from dental amalgam and evaluate current statements on dental amalgam. Materials and Methods. Two key-words “dental amalgam” and “toxicity” were used to search publications on dental amalgam biocompatibility published in peer-reviewed journals written in English. Manual search was also conducted. The most recent declarations and statements were evaluated using information available on ...

  3. Biocompatibility of Niobium Coatings

    OpenAIRE

    René Olivares-Navarrete; Jhon Jairo Olaya; Claudia Ramírez; Sandra Elizabeth Rodil

    2011-01-01

    Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS) substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainles...

  4. Biocompatibility of composite resins

    Directory of Open Access Journals (Sweden)

    Sayed Mostafa Mousavinasab

    2011-01-01

    Full Text Available Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concerns about their degradation and substances which may be segregated into oral cavity.

  5. Improved efficiency of organic/inorganic hybrid near-infrared light upconverter by device optimization.

    Science.gov (United States)

    Chu, Xinbo; Guan, Min; Li, Linsen; Zhang, Yang; Zhang, Feng; Li, Yiyang; Zhu, Zhanping; Wang, Baoqiang; Zeng, Yiping

    2012-09-26

    An organic/inorganic hybrid up-conversion device was demonstrated in this work, which can convert near-infrared light (NIR) to visible green at high conversion efficiency. The upconverter was fabricated by integrating an In(0.12)Ga(0.88)As/GaAs multiquantum wells (MQWs) photodetector (PD) with an organic light emitting diode (OLED). The up-conversion efficiency of 4.0 W/W % was obtained at 20 V under NIR illumination of 1 mW/mm(2) at room temperature by optimizing the structure of the PD unit and adding MoO(3) doped perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as interfacial layer of OLED. Meanwhile, the green light output induced by NIR achieved 6050 cd/m(2), which proves that the organic/inorganic hybrid upconverter an excellent candidate that can be applied in light converter field. PMID:22931090

  6. Biocompatibility of Niobium Coatings

    Directory of Open Access Journals (Sweden)

    René Olivares-Navarrete

    2011-09-01

    Full Text Available Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainless steel substrates and tissue culture plastic were also studied, in order to give comparative information. No toxic response was observed for any of the surfaces, indicating that the Nb coatings act as a biocompatible, bioinert material. Cell morphology was also studied by immune-fluorescence and the results confirmed the healthy state of the cells on the Nb surface. X-ray diffraction analysis of the coating shows that the film is polycrystalline with a body centered cubic structure. The surface composition and corrosion resistance of both the substrate and the Nb coating were also studied by X-ray photoelectron spectroscopy and potentiodynamic tests. Water contact angle measurements showed that the Nb surface is more hydrophobic than the SS substrate.

  7. Dynamics of a mechanical frequency up-converted device for wave energy harvesting

    Science.gov (United States)

    Lin, Zheng; Zhang, Yongliang

    2016-04-01

    This paper proposes a novel mechanical impact-driven frequency up-converted device for wave energy harvesting, which could bridge a gap between waves of frequency 0.03-1 Hz and electrical generators of operation frequency hundreds hertz. The device mainly consists of a cylindrical buoy, beams and teeth. A mathematical model for the dynamics of such a device is presented, which incorporates the fluid-structure interaction between the wave and the buoy, and the structural interactions between the beams and the teeth. The momentum balance method and the coefficient of restitution are employed, which give rise to piecewise nonlinear equations governing the motions of the buoy and the beams. Experimental tests carried out in a wave flume validate the model and prove the effectiveness of frequency up-converted method in wave energy harvesting. The characteristics of frequency up-converted transformation from buoy motion to beams oscillation for wave energy harvesting are probed, and the effects of beam Young's modulus, beam number, wave period and wave height on strain power of the beams are explored.

  8. Biocompatibility of fluorescent nanoparticles NaYF4:Yb,Er as imaging media%荧光纳米颗粒NaYF4:Yb,Er作为显像介质的生物相容性

    Institute of Scientific and Technical Information of China (English)

    虞永江; 马晓荣; 于国鹏; 高同斌; 齐隽; 陈方

    2011-01-01

    Objective To investigate the biocompatibility of upconversion fluorescent nanoparticles in vivo and in vitro, and verify its safety as imaging media.Methods Mouse bone mesenchymal stem cells (BMSC), mouse embryonic fibroblasts (NIH/3T3) and primary myoblasts (C2C12) were incubated with different concentrations of NaYF4: Yb, Er (0, 10, 50, 100 and 200 μg/mL).Cell proliferation was determined by MTT assay, and the formation of myotube cells from C2C12 myoblasts was detected.DMEM with NaYF4: Yb, Er nanoparticles were injected into C57BL/6 mice, and liver function and renal function were examined.HE staining was performed for main body organs, and toxicity was detected.Results MTT assay revealed that the cytotoxicity of NaYF4: Yb, Er on NIH/3T3 and C2C12 was positively correlated with incubation dose and time ( NIH/3T3: r =0.974, P <0.05; C2C12: r =0.996, P <0.05), while the same result was not found for BMSC ( r = - 0.218, P > 0.05).The formation of myotube cells from C2C12 myoblasts was not significantly affected by incubation with NaYF4: Yb, Er for 48 h.No obvious damage of liver and renal function and main body organs was observed after injection of DMEM with NaYF4: Yb, Er nanoparticles in mice.Conclusion As biological luminescent labels with strong intensity, NaYF4: Yb, Er has less toxicity both in vivo and in vitro to the requirement of imaging, and is an ideal biological imaging media.%目的 检测上转频荧光纳米颗粒的生物学体内、外相容性,证实其作为显像介质的生物安全性.方法 将培育后的小鼠骨髓间充质干细胞(BMSC)、胚胎成纤维细胞(NIH/3T3)及成肌细胞(C2C12)分别与不同浓度(0、10、50、100、200μg/mL)的NaYF4:Yb,Er共孵育,采用MTT法检测细胞的增殖活性,并测定C2C12成肌细胞形成肌管细胞的功能.将NaYF4:Yb,Er纳米颗粒DMEM混悬液注射入C57BL/6小鼠,行小鼠肝肾功能测定;并对重要脏器行HE组织学染色,检测小鼠的体内毒性.结果 MTT法细

  9. Electrospinning of Biocompatible Nanofibers

    Science.gov (United States)

    Coughlin, Andrew J.; Queen, Hailey A.; McCullen, Seth D.; Krause, Wendy E.

    2006-03-01

    Artificial scaffolds for growing cells can have a wide range of applications including wound coverings, supports in tissue cultures, drug delivery, and organ and tissue transplantation. Tissue engineering is a promising field which may resolve current problems with transplantation, such as rejection by the immune system and scarcity of donors. One approach to tissue engineering utilizes a biodegradable scaffold onto which cells are seeded and cultured, and ideally develop into functional tissue. The scaffold acts as an artificial extracellular matrix (ECM). Because a typical ECM contains collagen fibers with diameters of 50-500 nm, electrostatic spinning (electrospinning) was used to mimic the size and structure of these fibers. Electrospinning is a novel way of spinning a nonwoven web of fibers on the order of 100 nm, much like the web of collagen in an ECM. We are investigating the ability of several biocompatible polymers (e.g., chitosan and polyvinyl alcohol) to form defect-free nanofiber webs and are studying the influence of the zero shear rate viscosity, molecular weight, entanglement concentration, relaxation time, and solvent on the resulting fiber size and morphology.

  10. Image quality of up-converted 2D video from frame-compatible 3D video

    Science.gov (United States)

    Speranza, Filippo; Tam, Wa James; Vázquez, Carlos; Renaud, Ronald; Blanchfield, Phil

    2011-03-01

    In the stereoscopic frame-compatible format, the separate high-definition left and high-definition right views are reduced in resolution and packed to fit within the same video frame as a conventional two-dimensional high-definition signal. This format has been suggested for 3DTV since it does not require additional transmission bandwidth and entails only small changes to the existing broadcasting infrastructure. In some instances, the frame-compatible format might be used to deliver both 2D and 3D services, e.g., for over-the-air television services. In those cases, the video quality of the 2D service is bound to decrease since the 2D signal will have to be generated by up-converting one of the two views. In this study, we investigated such loss by measuring the perceptual image quality of 1080i and 720p up-converted video as compared to that of full resolution original 2D video. The video was encoded with either a MPEG-2 or a H.264/AVC codec at different bit rates and presented for viewing with either no polarized glasses (2D viewing mode) or with polarized glasses (3D viewing mode). The results confirmed a loss of video quality of the 2D video up-converted material. The loss due to the sampling processes inherent to the frame-compatible format was rather small for both 1080i and 720p video formats; the loss became more substantial with encoding, particularly for MPEG-2 encoding. The 3D viewing mode provided higher quality ratings, possibly because the visibility of the degradations was reduced.

  11. Nanoclusters of iron oxide: effect of core composition on structure, biocompatibility and cell labeling efficacy

    OpenAIRE

    van Tilborg, Geralda A. F.; Cormode, David P.; Jarzyna, Peter A.; van der Toorn, Annette; van der Pol, Susanne M. A.; van Bloois, Louis; Fayad, Zahi A.; Storm, Gert; Mulder, Willem J. M.; de Vries, Helga E.; Dijkhuizen, Rick M.

    2012-01-01

    Inorganic nanocrystals have a variety of applications in medicine. They may serve as contrast agents, therapeutics and for in vitro diagnostics. Frequently, the synthesis route yields hydrophobically capped nanocrystals, which necessitates their subsequent coating to render a water-soluble and biocompatible probe. Biocompatibility is crucial for cellular imaging applications, which require large quantities of diagnostically active nanoparticles to be loaded into cells. We have previously repo...

  12. Preorganized Chromophores Facilitate Triplet Energy Migration, Annihilation and Upconverted Singlet Energy Collection.

    Science.gov (United States)

    Mahato, Prasenjit; Yanai, Nobuhiro; Sindoro, Melinda; Granick, Steve; Kimizuka, Nobuo

    2016-05-25

    Photon upconversion (UC) based on triplet-triplet annihilation (TTA) has the potential to enhance significantly photovoltaic and photocatalytic efficiencies by harnessing sub-bandgap photons, but the progress of this field is held back by the chemistry problem of how to preorganize multiple chromophores for efficient UC under weak solar irradiance. Recently, the first maximization of UC quantum yield at solar irradiance was achieved using fast triplet energy migration (TEM) in metal-organic frameworks (MOFs) with ordered acceptor arrays, but at the same time, a trade-off between fast TEM and high fluorescence efficiency was also found. Here, we provide a solution for this trade-off issue by developing a new strategy, triplet energy migration, annihilation and upconverted singlet energy collection (TEM-UPCON). The porous structure of acceptor-based MOF crystals allows triplet donor molecules to be accommodated without aggregation. The surface of donor-doped MOF nanocrystals is modified with highly fluorescent energy collectors through coordination bond formation. Thanks to the higher fluorescence quantum yield of surface-bound collectors than parent MOFs, the implementation of the energy collector greatly improves the total UC quantum yield. The UC quantum yield maximization behavior at ultralow excitation intensity was retained because the TTA events take place only in the MOF acceptors. The TEM-UPCON concept may be generalized to collectors with various functions and would lead to quantitative harvesting of upconverted energy, which is difficult to achieve in common molecular diffusion-based systems.

  13. Biopolymeric nanoparticles

    Directory of Open Access Journals (Sweden)

    Sushmitha Sundar, Joydip Kundu and Subhas C Kundu

    2010-01-01

    Full Text Available This review on nanoparticles highlights the various biopolymers (proteins and polysaccharides which have recently revolutionized the world of biocompatible and degradable natural biological materials. The methods of their fabrication, including emulsification, desolvation, coacervation and electrospray drying are described. The characterization of different parameters for a given nanoparticle, such as particle size, surface charge, morphology, stability, structure, cellular uptake, cytotoxicity, drug loading and drug release, is outlined together with the relevant measurement techniques. Applications in the fields of medicine and biotechnology are discussed along with a promising future scope.

  14. Multi-modality nanoparticles having optically responsive shape

    Science.gov (United States)

    Chen, Fanqing; Bouchard, Louis-Serge

    2015-05-19

    In certain embodiments novel nanoparticles (nanowontons) are provided that are suitable for multimodal imaging and/or therapy. In one embodiment, the nanoparticles include a first biocompatible (e.g., gold) layer, an inner core layer (e.g., a non-biocompatible material), and a biocompatible (e.g., gold) layer. The first gold layer includes a concave surface that forms a first outer surface of the layered nanoparticle. The second gold layer includes a convex surface that forms a second outer surface of the layered nanoparticle. The first and second gold layers encapsulate the inner core material layer. Methods of fabricating such nanoparticles are also provided.

  15. nanoparticles

    Science.gov (United States)

    Andreu-Cabedo, Patricia; Mondragon, Rosa; Hernandez, Leonor; Martinez-Cuenca, Raul; Cabedo, Luis; Julia, J. Enrique

    2014-10-01

    Thermal energy storage (TES) is extremely important in concentrated solar power (CSP) plants since it represents the main difference and advantage of CSP plants with respect to other renewable energy sources such as wind, photovoltaic, etc. CSP represents a low-carbon emission renewable source of energy, and TES allows CSP plants to have energy availability and dispatchability using available industrial technologies. Molten salts are used in CSP plants as a TES material because of their high operational temperature and stability of up to 500°C. Their main drawbacks are their relative poor thermal properties and energy storage density. A simple cost-effective way to improve thermal properties of fluids is to dope them with nanoparticles, thus obtaining the so-called salt-based nanofluids. In this work, solar salt used in CSP plants (60% NaNO3 + 40% KNO3) was doped with silica nanoparticles at different solid mass concentrations (from 0.5% to 2%). Specific heat was measured by means of differential scanning calorimetry (DSC). A maximum increase of 25.03% was found at an optimal concentration of 1 wt.% of nanoparticles. The size distribution of nanoparticle clusters present in the salt at each concentration was evaluated by means of scanning electron microscopy (SEM) and image processing, as well as by means of dynamic light scattering (DLS). The cluster size and the specific surface available depended on the solid content, and a relationship between the specific heat increment and the available particle surface area was obtained. It was proved that the mechanism involved in the specific heat increment is based on a surface phenomenon. Stability of samples was tested for several thermal cycles and thermogravimetric analysis at high temperature was carried out, the samples being stable.

  16. Fabrication of a LRET-based upconverting hybrid nanocomposite for turn-on sensing of H2O2 and glucose

    Science.gov (United States)

    Wu, Shuang; Kong, Xiang-Juan; Cen, Yao; Yuan, Jing; Yu, Ru-Qin; Chu, Xia

    2016-04-01

    Blood glucose detecting has aroused considerable attention because diabetes mellitus has become a worldwide publish health problem. Herein, we construct an exceptionally simple upconverting hybrid nanocomposite, composed of DNA-templated Ag nanoparticles (DNA-AgNPs) and NaYF4:Yb/Tm@NaYF4 core-shell upconversion nanoparticles (UCNPs), for the sensing of H2O2 and glucose. In this design, UCNPs with bared surface act as the donor, and DNA-AgNPs serve as efficient quenchers. DNA-AgNPs can be directly assembled on the bared surface of UCNPs, which further decreases the distance of donor-to-acceptor. The formation of DNA-AgNPs/UCNP nanocomposite results in luminescence quenching of UCNP by DNA-AgNPs through luminescence resonance energy transfer (LRET). Upon H2O2 addition, AgNPs can be etched and transformed into Ag+, leading to inhibition of the LRET process and causing the recovery of upconversion luminescence. Based on the conversion of glucose into H2O2 by glucose oxidase, the DNA-AgNPs/UCNP nanocomposite can also be exploited for glucose sensing. Moreover, due to the non-autofluorescence offered by UCNPs, the approach developed can be applied to monitor glucose levels in human serum samples with satisfactory results.Blood glucose detecting has aroused considerable attention because diabetes mellitus has become a worldwide publish health problem. Herein, we construct an exceptionally simple upconverting hybrid nanocomposite, composed of DNA-templated Ag nanoparticles (DNA-AgNPs) and NaYF4:Yb/Tm@NaYF4 core-shell upconversion nanoparticles (UCNPs), for the sensing of H2O2 and glucose. In this design, UCNPs with bared surface act as the donor, and DNA-AgNPs serve as efficient quenchers. DNA-AgNPs can be directly assembled on the bared surface of UCNPs, which further decreases the distance of donor-to-acceptor. The formation of DNA-AgNPs/UCNP nanocomposite results in luminescence quenching of UCNP by DNA-AgNPs through luminescence resonance energy transfer (LRET). Upon H

  17. Adhesion of biocompatible and biodegradable micropatterned surfaces

    NARCIS (Netherlands)

    Kaiser, J.S.; Kamperman, M.M.G.; Souza, E.J.; Schick, B.; Arzt, E.

    2011-01-01

    We studied the effects of pillar dimensions and stiffness of biocompatible and biodegradable micropatterned surfaces on adhesion on different compliant substrates. The micropatterned adhesives were based on biocompatible polydimethylsiloxane (PDMS) and biodegradable poly(lactic-co-glycolic) acid (PL

  18. Biocompatible Collagen Paramagnetic Scaffold for Controlled Drug Release.

    Science.gov (United States)

    Bettini, Simona; Bonfrate, Valentina; Syrgiannis, Zois; Sannino, Alessandro; Salvatore, Luca; Madaghiele, Marta; Valli, Ludovico; Giancane, Gabriele

    2015-09-14

    A porous collagen-based hydrogel scaffold was prepared in the presence of iron oxide nanoparticles (NPs) and was characterized by means of infrared spectroscopy and scanning electron microscopy. The hybrid scaffold was then loaded with fluorescein sodium salt as a model compound. The release of the hydrosoluble species was triggered and accurately controlled by the application of an external magnetic field, as monitored by fluorescence spectroscopy. The biocompatibility of the proposed matrix was also tested by the MTT assay performed on 3T3 cells. Cell viability was only slightly reduced when the cells were incubated in the presence of the collagen-NP hydrogel, compared to controls. The economicity of the chemical protocol used to obtain the paramagnetic scaffolds as well as their biocompatibility and the safety of the external trigger needed to induce the drug release suggest the proposed collagen paramagnetic matrices for a number of applications including tissue engeneering and drug delivery. PMID:26270197

  19. Plasmon-enhanced random lasing in bio-compatible networks of cellulose nanofibers

    Science.gov (United States)

    Zhang, R.; Knitter, S.; Liew, S. F.; Omenetto, F. G.; Reinhard, B. M.; Cao, H.; Dal Negro, L.

    2016-01-01

    We report on plasmon-enhanced random lasing in bio-compatible light emitting Hydroxypropyl Cellulose (HPC) nanofiber networks doped with gold nanoparticles. HPC nanofibers with a diameter of 260 ± 30 nm were synthesized by a one step, cost-effective and facile electrospinning technique from a solution-containing Rhodamine 6G and Au nanoparticles. Nanoparticles of controlled diameters from 10 nm to 80 nm were dispersed inside the nanofibers and optically characterized using photoluminescence, dark-field spectroscopy, and coherent backscattering measurements. Plasmon-enhanced random lasing was demonstrated with a lower threshold than that in dye-doped identical HPC networks without Au nanoparticles. These findings provide an effective approach for plasmon-enhanced random lasers based on a bio-compatible host matrix that is particularly attractive for biophotonic applications such as fluorescence sensing, optical tagging, and detection.

  20. An up-converting phosphor technology based lateral flow assay for rapid detection of Listeria monocytogenes%基于上转发光免疫层析技术快速检测单核细胞增生李斯特菌

    Institute of Scientific and Technical Information of China (English)

    刘旭; 李春凤; 王晓英; 冯娜; 杨瑞馥; 王成彬; 周蕾

    2014-01-01

    Objective To develop an up-converting phosphor technology-based lateral-flow ( UPT-LF) assay for rapid detection of Listeria monocytogenes, named LM -UPT-LF.Methods Monoclonal antibodies against p 60, which was the specific virulence factor of L.monocytogenes,were prepared and covalently conjugated with up-converting phosphor nanopar-ticles (UCP-NPs) as bio-label.Then, LM-UPT-LF was established with double-antibody sandwich mode-based LF assay. Detection performance , including sensitivity and specificity , was evaluated .Results The samples with absolute contamina-ted amount of L.monocytogenes cells <10, 10-99, and 100-1000 cfu could be significantly detected as positive after in-cubation at 20 h, 18 h, and 16 h, respectively.Other 13 kinds of food-borne pathogens with concentration of 109 cfu/ml did not caused any non-specific reaction .Conclusion The established LM-UPT-LF assay could detect L.monocytogenes with high sensitivity , specificity and simplicity and provides an alternative method for food safety control .%目的:建立可快速检测单核细胞增生李斯特菌( Listeria monocytogenes, LM)的上转发光免疫层析技术( up-converting phosphor technology based lateral flow assay , UPT-LF),即LM-UPT-LF。方法针对LM特异的p60蛋白制备单克隆抗体,并与上转发光纳米颗粒( up-converting phosphor nanoparticles , UCP-NPs)共价偶联作为结合物,采用双抗体夹心免疫层析模式建立LM-UPT-LF,并对其敏感性与特异性进行评价。结果建立了可快速检测LM的LM-UPT-LF平台,在样本<10 cfu、10~99 cfu、100~1000 cfu绝对LM污染量条件下可分别在培养20、18、16 h检出阳性。其他13种食源性致病菌在高浓度(109 cfu/ml)时无非特异性交叉。结论所建立的LM-UPT-LF操作简便快速,具有良好的敏感性和特异性,适用于一线病原调查与检测。

  1. [Magnetic nanoparticles and intracellular delivery of biopolymers].

    Science.gov (United States)

    Kornev, A A; Dubina, M V

    2014-03-01

    The basic methods of intracellular delivery of biopolymers are present in this review. The structure and synthesis of magnetic nanoparticles, their stabilizing surfactants are described. The examples of the interaction of nanoparticles with biopolymers such as nucleic acids and proteins are considered. The final part of the review is devoted to problems physiology and biocompatibility of magnetic nanoparticles.

  2. Nanoparticles in forensic science

    Science.gov (United States)

    Cantu, Antonio A.

    2008-10-01

    Nanoparticles appear in several areas of forensic science including security documents, paints, inks, and reagents that develop latent prints. One reagent (known as the silver physical developer) that visualizes the water insoluble components of latent print residue is based on the formation of highly charged silver nanoparticles. These attach to and grow on the residue and generate a silver image. Another such reagent involves highly charged gold nanoparticles. These attach to the residue forming a weak gold image which can be amplified with a silver physical developer. Nanoparaticles are also used in items such as paints, printing inks, and writing inks. Paints and most printing inks consist of nano-sized pigments in a vehicle. However, certain modern ink jet printing inks now contain nano-sized pigments to improve their light fastness and most gel inks are also based on nano scale pigments. These nanoparticlecontaining materials often appear as evidence and are thus subject to forensic characterization. Both luminescent (quantum dots), up-converting nano scale phosphors, and non luminescent nanoparticles are used as security tags to label product, add security to documents, and as anti counterfeiting measures. These assist in determining if an item is fraudulently made.

  3. Development of novel biocompatible hybrid nanocomposites based on polyurethane-silica prepared by sol gel process.

    Science.gov (United States)

    Rashti, Ali; Yahyaei, Hossein; Firoozi, Saman; Ramezani, Sara; Rahiminejad, Ali; Karimi, Roya; Farzaneh, Khadijeh; Mohseni, Mohsen; Ghanbari, Hossein

    2016-12-01

    Due to high biocompatibility, polyurethane has found many applications, particularly in development of biomedical devices. A new nanocomposite based on thermoset polyurethane and silica nanoparticles was synthesized using sol-gel method. Sol-gel process was fulfilled in two acidic and basic conditions by using tetraethylorthosilicate (TEOS) and trimethoxyisocyanatesilane as precursors. The hybrid films characterized for mechanical and surface properties using tensile strength, contact angle, ATR-FTIR and scanning electron microscopy. Biocompatibility and cytotoxicity of the hybrids were assessed using standard MTT, LDH and TUNEL assays. The results revealed that incorporation of silica nanoparticles was significantly improved tensile strength and mechanical properties of the hybrids. Based on the contact angle results, silica nanoparticles increased hydrophilicity of the hybrids. Biocompatibility by using human lung epithelial cell line (MRC-5) demonstrated that the hybrids were significantly less cytotoxic compared to pristine polymer as tested by MTT and LDH assays. TUNEL assay revealed no signs of apoptosis in all tested samples. The results of this study demonstrated that incorporation of silica nanoparticles into polyurethane lead to the enhancement of biocompatibility, indicating that these hybrids could potentially be used in biomedical field in particular as a new coating for medical implants. PMID:27612823

  4. Biocompatible polysaccharide-based cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Reichelt, Senta, E-mail: senta.reichelt@iom-leipzig.de [Leibniz Institute of Surface Modification, Permoserstr. 15, 04318 Leipzig (Germany); Becher, Jana; Weisser, Jürgen [Innovent e.V., Pruessingstr. 27B, 07745 Jena (Germany); Prager, Andrea; Decker, Ulrich [Leibniz Institute of Surface Modification, Permoserstr. 15, 04318 Leipzig (Germany); Möller, Stephanie; Berg, Albrecht; Schnabelrauch, Matthias [Innovent e.V., Pruessingstr. 27B, 07745 Jena (Germany)

    2014-02-01

    This study focuses on the development of novel biocompatible macroporous cryogels by electron-beam assisted free-radical crosslinking reaction of polymerizable dextran and hyaluronan derivatives. As a main advantage this straightforward approach provides highly pure materials of high porosity without using additional crosslinkers or initiators. The cryogels were characterized with regard to their morphology and their basic properties including thermal and mechanical characteristics, and swellability. It was found that the applied irradiation dose and the chemical composition strongly influence the material properties of the resulting cryogels. Preliminary cytotoxicity tests illustrate the excellent in vitro-cytocompatibility of the fabricated cryogels making them especially attractive as matrices in tissue regeneration procedures. - Graphical abstract: Electron-beam initiated synthesis of biocompatible cryogels based on natural polymers. - Highlights: • Successful electron-beam induced synthesis of dextran and hyaluronan cryogels. • Mechanical and thermal stable cryogels were obtained. • Excellent cytocompatibility of the materials was proven. • Promising materials for tissue engineering were developed.

  5. Biocompatible and Bioeliminable Hydrophilic Polymers

    Institute of Scientific and Technical Information of China (English)

    Paolo; FerrutiUniversità

    2007-01-01

    1 Introduction This presentation will report on some recent results obtained in Milan on two polymer families of biomedical interest, namely poly(N-vinyl-2-pyrrolidinone) and polyamidoamines. 2 Results and DiscussionPoly(N-vinyl-2-pyrrolidinone) (PVP) is a well known bioactive and biocompatible polymer. In its soluble form, it is largely used as excipient of oral pharmaceutical formulations, especially for its high water solubilising power.In its crosslinked form, it plays a relevant role as biomateria...

  6. Biocompatible polyurethane/thiacalix[4]arenes functionalized Fe3O4 magnetic nanocomposites: Synthesis and properties.

    Science.gov (United States)

    Mohammadi, Abbas; Barikani, Mehdi; Lakouraj, Moslem Mansour

    2016-09-01

    In this study, a series of magnetic polyurethane/Fe3O4 elastomer nanocomposites were prepared by covalently embedding novel thiacalix[4]arenes (TC4As) functionalized Fe3O4 nanoparticles (TC4As-Fe3O4) which contain macrocycles with reactive hydroxyl groups. Surface functionalization of Fe3O4 nanoparticles with TC4As macrocycles as unique reactive surface modifier not only gives specific characteristics to Fe3O4 nanoparticles but also improves the interphase interaction between nanoparticles and the polyurethane matrices through covalent attachment of polymer chains to nanoparticle surfaces. The novel synthesized TC4As-Fe3O4 nanoparticles were characterized by FTIR, XRD, TGA, VSM and SEM analysis. Furthermore, the effect of functionalization of Fe3O4 nanoparticles on the various properties of resulting nanocomposites was studied by XRD, TGA, DMTA, SEM, and a universal tensile tester. It was found that the functionalization of nanoparticles with TC4As affords better mechanical and thermal properties to polyurethane nanocomposites in comparison with unmodified nanoparticles. The SEM analysis showed finer dispersion of TC4As-Fe3O4 nanoparticles than unmodified Fe3O4 nanoparticles within the polyurethane matrices, which arising from formation of covalent bonding between TC4As functionalized Fe3O4 nanoparticles and polyurethane matrices. Moreover, the investigation of in vitro biocompatibility of novel nanocomposites showed that these samples are excellent candidate for biomedical use. PMID:27207044

  7. 3D Printing of Biocompatible Supramolecular Polymers and their Composites.

    Science.gov (United States)

    Hart, Lewis R; Li, Siwei; Sturgess, Craig; Wildman, Ricky; Jones, Julian R; Hayes, Wayne

    2016-02-10

    A series of polymers capable of self-assembling into infinite networks via supramolecular interactions have been designed, synthesized, and characterized for use in 3D printing applications. The biocompatible polymers and their composites with silica nanoparticles were successfully utilized to deposit both simple cubic structures, as well as a more complex twisted pyramidal feature. The polymers were found to be not toxic to a chondrogenic cell line, according to ISO 10993-5 and 10993-12 standard tests and the cells attached to the supramolecular polymers as demonstrated by confocal microscopy. Silica nanoparticles were then dispersed within the polymer matrix, yielding a composite material which was optimized for inkjet printing. The hybrid material showed promise in preliminary tests to facilitate the 3D deposition of a more complex structure.

  8. 3D Printing of Biocompatible Supramolecular Polymers and their Composites.

    Science.gov (United States)

    Hart, Lewis R; Li, Siwei; Sturgess, Craig; Wildman, Ricky; Jones, Julian R; Hayes, Wayne

    2016-02-10

    A series of polymers capable of self-assembling into infinite networks via supramolecular interactions have been designed, synthesized, and characterized for use in 3D printing applications. The biocompatible polymers and their composites with silica nanoparticles were successfully utilized to deposit both simple cubic structures, as well as a more complex twisted pyramidal feature. The polymers were found to be not toxic to a chondrogenic cell line, according to ISO 10993-5 and 10993-12 standard tests and the cells attached to the supramolecular polymers as demonstrated by confocal microscopy. Silica nanoparticles were then dispersed within the polymer matrix, yielding a composite material which was optimized for inkjet printing. The hybrid material showed promise in preliminary tests to facilitate the 3D deposition of a more complex structure. PMID:26766139

  9. A rheological and microscopical characterization of biocompatible ferrofluids

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, J., E-mail: johannes.nowak@tu-dresden.de [Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, 01069 Germany (Germany); Wolf, D. [Triebenberg Laboratory, Technische Universität Dresden, 01328 Germany (Germany); Odenbach, S. [Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, 01069 Germany (Germany)

    2014-03-15

    There is an increasing interest in suspensions of magnetic nanoparticles in the biomedical area. Those ferrofluids are e.g. used for magnetic resonance imaging and emerging research focuses on employing the fluids for magnetic drug targeting or magnetic particle heating as a potential treatment for cancer. For these applications the knowledge of the suspensions' thermophysical properties is of major interest to guarantee a safe and effective application. Therefore the flow behavior cannot be neglected as it might significantly influence the execution of the aforementioned applications. In this experimental study two biocompatible ferrofluids were investigated. Rheological measurements were carried out using rotational rheometry. To allow an interpretation of the fluids' behavior the microscopic make-up was investigated using dynamic light scattering and transmission electron microscopy. Measurements of diluted ferrofluids were carried out as a first step to simulate the rheological behavior reflecting the concentration of magnetic nanoparticles found in blood flow for most biomedical applications of such fluids. The detected strong effects show the potential to significantly influence application and handling of the biocompatible ferrofluids in the medical area and should therefore be taken into account for further research as well as for the application of such fluids. - Highlights: • The rheology of biocompatible multicore ferrofluids is influenced by magnetic fields. • The flow curves can be described by the Herschel–Bulkley model. • A connection between the magnetoviscous effect and the particle size is found. • The strong magnetoviscous effect exists even if the fluids are diluted. • The connection between the effect and the dilution is mathematically described.

  10. Biocompatibility of plasma nanostructured biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Slepičková Kasálková, N. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Slepička, P., E-mail: petr.slepicka@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Bačáková, L. [Institute of Physiology, Academy of Sciences of the Czech Republic 142 20 Prague (Czech Republic); Sajdl, P. [Department of Power Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Švorčík, V. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic)

    2013-07-15

    Many areas of medicine such as tissue engineering requires not only mastery of modification techniques but also thorough knowledge of the interaction of cells with solid state substrates. Plasma treatment can be used to effective modification, nanostructuring and therefore can significantly change properties of materials. In this work the biocompatibility of the plasma nanostructured biopolymers substrates was studied. Changes in surface chemical structure were studied by X-ray photoelectron spectroscopy (XPS). The morphology pristine and modified samples were determined using atomic force microscopy (AFM). The surface wettability was determined by goniometry from contact angle. Biocompatibility was determined by in vitro tests, the rat vascular smooth muscle cells (VSMCs) were cultivated on the pristine and plasma modified biopolymer substrates. Their adhesion, proliferation, spreading and homogeneous distribution on polymers was monitored. It was found that the plasma treatment leads to rapid decrease of contact angle for all samples. Contact angle decreased with increasing time of modification. XPS measurements showed that plasma treatment leads to changes in ratio of polar and non-polar groups. Plasma modification was accompanied by a change of surface morphology. Biological tests found that plasma treatment have positive effect on cells adhesion and proliferation cells and affects the size of cell’s adhesion area. Changes in plasma power or in exposure time influences the number of adhered and proliferated cells and their distribution on biopolymer surface.

  11. The Biocompatibility of Wool Keratin

    Institute of Scientific and Technical Information of China (English)

    LIU Mei; YU Wei-dong; WANG Xue-lei

    2007-01-01

    Keratin is the major structural fibrous protein providing outer covering such as hair, wool, feathers, etc. When being used as a kind of biomaterials, the biocompatibility of wool keratin is one of the most critical questions. By now, there has not been systemic study on the biocompatibiiity of keratin. Therefore, in this article we used the procedures of skin irritation, haemolysis and subcutaneous implantation according to ISO 10993 to study it. Moreover, the Fourier transform-infrared (FTIR) spectroscopy was utilized to analyse the impurity and structure modification of wool keratin film. The part of the animal tests showed that the wool keratin films prepared by authors were biocompatible. But the residual of sodium dodecyi sulfate (SDS) affected the results of other tests. Consequently, the wool keratin membrane is one kind of favourable and promising biomaterial for biomedical and histological utilization. The residual SDS used as an agent should be eliminated from the keratin solution or membrane completely if for biological usage. In conclusion, wool keratin, as a kind of natural protein, prospectively could be applied in biomedical materials and scaffolds of tissue engineering.

  12. Bioglass: A novel biocompatible innovation

    Directory of Open Access Journals (Sweden)

    Vidya Krishnan

    2013-01-01

    Full Text Available Advancement of materials technology has been immense, especially in the past 30 years. Ceramics has not been new to dentistry. Porcelain crowns, silica fillers in composite resins, and glass ionomer cements have already been proved to be successful. Materials used in the replacement of tissues have come a long way from being inert, to compatible, and now regenerative. When hydroxyapatite was believed to be the best biocompatible replacement material, Larry Hench developed a material using silica (glass as the host material, incorporated with calcium and phosphorous to fuse broken bones. This material mimics bone material and stimulates the regrowth of new bone material. Thus, due to its biocompatibility and osteogenic capacity it came to be known as "bioactive glass-bioglass." It is now encompassed, along with synthetic hydroxyapatite, in the field of biomaterials science known as "bioactive ceramics." The aim of this article is to give a bird′s-eye view, of the various uses in dentistry, of this novel, miracle material which can bond, induce osteogenesis, and also regenerate bone.

  13. Electromechanical behavior of a pendulum-based piezoelectric frequency up-converting energy harvester

    Science.gov (United States)

    Ramezanpour, Reza; Nahvi, Hassan; Ziaei-Rad, Saeed

    2016-05-01

    In the present study, the possibility to extract more vibrational energy by utilizing a high number of magnets on the proof mass of a piezoelectric frequency up-converting energy harvester is investigated. Due to magnetic interaction, the beam is actuated whenever the proof mass passes over its tip. It is observed that several peaks occur in the voltage signal of PZT beam when the angular velocity of the proof mass increases linearly. It is shown that the peaks locations which found to be dependent on the natural frequency of the PZT beam as well as the number of rotating magnets can be estimated by a mathematical formulation. Considering the effects of magnetic interactions on the pendulum dynamics, the generated power of the harvester is obtained for harmonic excitations. Although the determination of exact optimum number of magnets that can lead to the best generated power in all excitation characteristics is impossible, it is found that by applying an appropriate number of rotating magnets (e.g. six, seven or eight magnets), the extracted power from high amplitude excitations can be enhanced. It is noteworthy that, at some particular cases, it is possible that the generated power be increased to even more than ten times. At the end, by conducting some experiments, the validity of the mathematical modeling as well as the applied numerical method is examined.

  14. Superparamagnetic iron oxide/chitosan core/shells for hyperthermia application: Improved colloidal stability and biocompatibility

    Science.gov (United States)

    Patil, R. M.; Shete, P. B.; Thorat, N. D.; Otari, S. V.; Barick, K. C.; Prasad, A.; Ningthoujam, R. S.; Tiwale, B. M.; Pawar, S. H.

    2014-04-01

    Superparamagnetic magnetite nanoparticles are of great interest due to their potential biomedical applications. In the present investigation, Fe3O4 magnetic nanoparticles were prepared by alkaline precipitation using ferrous chloride as the sole source. An amphiphilic polyelectrolyte with the property of biocompatibility and functional carboxyl groups was used as a stabilizer to prepare a well-dispersed suspension of superparamagnetic Fe3O4 nanoparticles. The final material composed of Fe3O4 core and chitosan (CH) shell was produced. The amino groups of CH coated on Fe3O4 nanoparticles were further cross linked using glutaraldehyde (GLD) for stable coating. FTIR spectra, XPS and TGA confirmed the coating of CH/GLD on the surface of Fe3O4 nanoparticles. XRD patterns indicate the pure phase Fe3O4 with a spinel structure. The nanoparticles were superparamagnetic at room temperature with saturation magnetization values for bare and coated nanoparticles which were 51.68 emu/g and 48.60 emu/g, respectively. Zeta potential values showed higher colloidal stability of coated nanoparticles than the bare one. Cytotoxicity study up to 2 mg mL-1 concentration showed no drastic change in cell viability of nanoparticles after coating. Also, coated nanoparticles showed increased SAR value, making them suitable for hyperthermia therapy application.

  15. The use of upconverting phosphors in point-of-care (POC) testing

    Science.gov (United States)

    Tanke, Hans J.; Zuiderwijk, Michel; Wiesmeijer, Karien C.; Breedveld, Robert N.; Abrams, William R.; de Dood, Claudia J.; Tjon Kon Fat, Elisa M.; Corstjens, Paul L. A. M.

    2014-03-01

    Point-of-care (POC) testing is increasingly applied as a cost effective alternative to many diagnostic tests. Key in POC testing is to create sufficient assay sensitivity with relatively low cost reagents and equipment. For this purpose we have employed a unique reporter, upconverting phosphor (UCP) particles, in combination with lateral flow (LF) assays. UCPs, submicron ceramic particles doped with rare earth ions (lanthanides), convert infrared to visible light and do not suffer from autofluorescence which limits conventional fluorescence based assays. Low cost handheld readers and microfluidics were evaluated in various applications. Designed assays are well suited for applications outside diagnostic laboratories, in resource poor settings, and can even be used by patients at home. Using two distinctly different UCP-LF assay formats, we focussed on assays for infectious diseases based on the detection of pathogen-specific antibodies and/or antigens including nucleic acids to demonstrate active infection with HIV. Only minor adaptation of the standard UCP-LF assay format is needed to render the format suitable for applications involving low affinity capture antibodies (e.g. in the detection of neurotoxin, botulism), capture of small molecules (e.g. detection of melatonin, a key hormone in chronopharmacology) or the use of dry UCP reagents (e.g. detection of protein based fruit-ripening markers, of economic interest in agriculture). Finally, we anticipate on developments in healthcare (personalized medicine) by discussing the potential of one of the UCP-LF assay formats to measure serum trough levels of immunodrugs (e.g. infliximab or adalimumab) in patients treated for inflammatory bowel disease and rheumatoid arthritis.

  16. Translational Applications of Nanodiamonds: From Biocompatibility to Theranostics

    Science.gov (United States)

    Moore, Laura Kent

    Nanotechnology marks the next phase of development for drug delivery, contrast agents and gene therapy. For these novel systems to achieve success in clinical translation we must see that they are both effective and safe. Diamond nanoparticles, also known as nanodiamonds (NDs), have been gaining popularity as molecular delivery vehicles over the last decade. The uniquely faceted, carbon nanoparticles possess a number of beneficial properties that are being harnessed for applications ranging from small-molecule drug delivery to biomedical imaging and gene therapy. In addition to improving the effectiveness of a variety of therapeutics and contrast agents, initial studies indicate that NDs are biocompatible. In this work we evaluate the translational potential of NDs by demonstrating efficacy in molecular delivery and scrutinizing particle tolerance. Previous work has demonstrated that NDs are effective vehicles for the delivery of anthracycline chemotherapeutics and gadolinium(III) based contrast agents. We have sought to enhance the gains made in both areas through the addition of active targeting. We find that ND-mediated targeted delivery of epirubicin to triple negative breast cancers induces tumor regression and virtually eliminates drug toxicities. Additionally, ND-mediated delivery of the MRI contrast agent ProGlo boosts the per gadolinium relaxivity four fold, eliminates water solubility issues and effectively labels progesterone receptor expressing breast cancer cells. Both strategies open the door to the development of targeted, theranostic constructs based on NDs, capable of treating and labeling breast cancers at the same time. Although we have seen that NDs are effective vehicles for molecular delivery, for any nanoparticle to achieve clinical utility it must be biocompatible. Preliminary research has shown that NDs are non-toxic, however only a fraction of the ND-subtypes have been evaluated. Here we present an in depth analysis of the cellular

  17. Biocompatibility of chemical-vapour-deposited diamond.

    Science.gov (United States)

    Tang, L; Tsai, C; Gerberich, W W; Kruckeberg, L; Kania, D R

    1995-04-01

    The biocompatibility of chemical-vapour-deposited (CVD) diamond surfaces has been assessed. Our results indicate that CVD diamond is as biocompatible as titanium (Ti) and 316 stainless steel (SS). First, the amount of adsorbed and 'denatured' fibrinogen on CVD diamond was very close to that of Ti and SS. Second, both in vitro and in vivo there appears to be less cellular adhesion and activation on the surface of CVD diamond surfaces compared to Ti and SS. This evident biocompatibility, coupled with the corrosion resistance and notable mechanical integrity of CVD diamond, suggests that diamond-coated surfaces may be highly desirable in a number of biomedical applications. PMID:7654876

  18. Biocompatible magnetic core-shell nanocomposites for engineered magnetic tissues

    Science.gov (United States)

    Rodriguez-Arco, Laura; Rodriguez, Ismael A.; Carriel, Victor; Bonhome-Espinosa, Ana B.; Campos, Fernando; Kuzhir, Pavel; Duran, Juan D. G.; Lopez-Lopez, Modesto T.

    2016-04-01

    The inclusion of magnetic nanoparticles into biopolymer matrixes enables the preparation of magnetic field-responsive engineered tissues. Here we describe a synthetic route to prepare biocompatible core-shell nanostructures consisting of a polymeric core and a magnetic shell, which are used for this purpose. We show that using a core-shell architecture is doubly advantageous. First, gravitational settling for core-shell nanocomposites is slower because of the reduction of the composite average density connected to the light polymer core. Second, the magnetic response of core-shell nanocomposites can be tuned by changing the thickness of the magnetic layer. The incorporation of the composites into biopolymer hydrogels containing cells results in magnetic field-responsive engineered tissues whose mechanical properties can be controlled by external magnetic forces. Indeed, we obtain a significant increase of the viscoelastic moduli of the engineered tissues when exposed to an external magnetic field. Because the composites are functionalized with polyethylene glycol, the prepared bio-artificial tissue-like constructs also display excellent ex vivo cell viability and proliferation. When implanted in vivo, the engineered tissues show good biocompatibility and outstanding interaction with the host tissue. Actually, they only cause a localized transitory inflammatory reaction at the implantation site, without any effect on other organs. Altogether, our results suggest that the inclusion of magnetic core-shell nanocomposites into biomaterials would enable tissue engineering of artificial substitutes whose mechanical properties could be tuned to match those of the potential target tissue. In a wider perspective, the good biocompatibility and magnetic behavior of the composites could be beneficial for many other applications.The inclusion of magnetic nanoparticles into biopolymer matrixes enables the preparation of magnetic field-responsive engineered tissues. Here we

  19. Aspartame-stabilized gold-silver bimetallic biocompatible nanostructures with plasmonic photothermal properties, antibacterial activity, and long-term stability.

    Science.gov (United States)

    Fasciani, Chiara; Silvero, M Jazmin; Anghel, Maria Alexandra; Argüello, Gerardo A; Becerra, Maria Cecilia; Scaiano, Juan C

    2014-12-17

    Gold-silver core-shell nanoparticles stabilized with a common sweetener, aspartame (AuNP@Ag@Asm), combine the antimicrobial properties of silver with the photoinduced plasmon-mediated photothermal effects of gold. The particles were tested with several bacterial strains, while biocompatibility was verified with human dermal fibroblasts.

  20. In vivo bone biocompatibility and degradation of porous fumarate-based polymer/alumoxane nanocomposites for bone tissue engineering.

    NARCIS (Netherlands)

    Mistry, A.S.; Pham, Q.P.; Schouten, C.; Yeh, T.; Christenson, E.M.; Mikos, A.G.; Jansen, J.A.

    2010-01-01

    The objective of this study was to determine how the incorporation of surface-modified alumoxane nanoparticles into a biodegradable fumarate-based polymer affects in vivo bone biocompatibility (characterized by direct bone contact and bone ingrowth) and in vivo degradability. Porous scaffolds were f

  1. A capillary viscometer designed for the characterization of biocompatible ferrofluids

    Science.gov (United States)

    Nowak, J.; Odenbach, S.

    2016-08-01

    Suspensions of magnetic nanoparticles are receiving a growing interest in biomedical research. These ferrofluids can, e.g., be used for the treatment of cancer, making use of the drug targeting principle or using an artificially induced heating. To enable a safe application the basic properties of the ferrofluids have to be well understood, including the viscosity of the fluids if an external magnetic field is applied. It is well known that the viscosity of ferrofluids rises if a magnetic field is applied, where the rise depends on shear rate and magnetic field strength. In case of biocompatible ferrofluids such investigations proved to be rather complicated as the experimental setup should be close to the actual application to allow justified predictions of the effects which have to be expected. Thus a capillary viscometer, providing a flow situation comparable to the flow in a blood vessel, has been designed. The glass capillary is exchangeable and different inner diameters can be used. The range of the shear rates has been adapted to the range found in the human organism. The application of an external magnetic field is enabled with two different coil setups covering the ranges of magnetic field strengths required on the one hand for a theoretical understanding of particle interaction and resulting changes in viscosity and on the other hand for values necessary for a potential biomedical application. The results show that the newly designed capillary viscometer is suitable to measure the magnetoviscous effect in biocompatible ferrofluids and that the results appear to be consistent with data measured with rotational rheometry. In addition, a strong change of the flow behaviour of a biocompatible ferrofluid was proven for ranges of the shear rate and the magnetic field strength expected for a potential biomedical application.

  2. 980-nm laser-driven photovoltaic cells based on rare-earth up-converting phosphors for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhigang [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering, Donghua University Shanghai (China); Max Planck Institute for Colloids and Interfaces, Potsdam (Germany); Zhang, Lisha [Department of Biology, Chinese University of Hong Kong Shatin, NT, Hong Kong SAR (China); Sun, Yangang; Hu, Junqing [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering, Donghua University Shanghai (China); Wang, Dayang [Max Planck Institute for Colloids and Interfaces, Potsdam (Germany)

    2009-12-09

    A prerequisite for designing and constructing wireless biological nanorobots is to obtain an electrical source that is continuously available in the operational biological environment. Herein the first preparation of 980-nm laser-driven photovoltaic cells (980LD-PVCs) by introducing of a film of rare-earth up-converting nanophosphors in conventional dye-sensitized solar cells is reported. Under the irradiation of a 980-nm laser with a power of 1 W, the visible up-converting luminescence of rare-earth nanophosphors can be efficiently absorbed by the dyes in 980LD-PVCs so that they exhibit a maximal output power of 0.47 mW. In particular, after being covered with 1 to 6 layers of pig intestines (thickness: ca. 1 mm per layer) as a model of biological tissues, 980LD-PVCs still possess a maximal output power of between 0.28 and 0.02 mW, which is efficient enough to drive many kinds of biodevices. This research opens up the possibility of preparing and/or developing novel electrical sources for wireless biological nanorobots and many other biodevices. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  3. All optical up-converted signal generation with high dispersion tolerance using frequency quadrupling technique for radio over fiber system

    Science.gov (United States)

    Gu, Yiying; Zhao, Jiayi; Hu, Jingjing; Kang, Zijian; Zhu, Wenwu; Fan, Feng; Han, Xiuyou; Zhao, Mingshan

    2016-05-01

    A novel all optical up-converted signal generation scheme with optical single-sideband (OSSB) technique for radio over fiber (RoF) application is presented and experimentally demonstrated using low-bandwidth devices. The OSSB signal is generated by one low-bandwidth intensity LiNbO3 Mach-Zehnder modulator (LN-MZM) under frequency quadrupling modulation scheme and one low-bandwidth LN-MZM under double sideband carrier suppressed modulation (DSB-CS) scheme. The proposed all OSSB generation scheme is capable of high tolerance of fiber chromatic dispersion induced power fading (DIPF) effect. Benefiting from this novel OSSB generation scheme, a 26 GHz radio frequency (RF) signal up-conversion is realized successfully when one sideband of the optical LO signal is reused as the optical carrier for intermediate frequency (IF) signal modulation. The received vector signal transmission over long distance single-mode fiber (SMF) shows negligible DIPF effect with the error vector magnitude (EVM) of 15.7% rms. In addition, a spurious free dynamic range (SFDR) of the OSSB up-converting system is measured up to 81 dB Hz2/3. The experiment results indicate that the proposed system may find potential applications in future wireless communication networks, especially in microcellular personal communication system (MPCS).

  4. Biomimetic, Mild Chemical Synthesis of CdTe-GSH Quantum Dots with Improved Biocompatibility

    OpenAIRE

    Pérez-Donoso, José M.; Monrás, Juan P; Denisse Bravo; Adam Aguirre; Quest, Andrew F.; Igor O Osorio-Román; Aroca, Ricardo F.; Chasteen, Thomas G.; Vásquez, Claudio C.

    2012-01-01

    Multiple applications of nanotechnology, especially those involving highly fluorescent nanoparticles (NPs) or quantum dots (QDs) have stimulated the research to develop simple, rapid and environmentally friendly protocols for synthesizing NPs exhibiting novel properties and increased biocompatibility. In this study, a simple protocol for the chemical synthesis of glutathione (GSH)-capped CdTe QDs (CdTe-GSH) resembling conditions found in biological systems is described. Using only CdCl(2), K(...

  5. Broadband photonic single sideband frequency up-converter based on the cross polarization modulation effect in a semiconductor optical amplifier for radio-over-fiber systems.

    Science.gov (United States)

    Lee, Seung-Hun; Kim, Hyoung-Jun; Song, Jong-In

    2014-01-13

    A broadband photonic single sideband (SSB) frequency up-converter based on the cross polarization modulation (XPolM) effect in a semiconductor optical amplifier (SOA) is proposed and experimentally demonstrated. An optical radio frequency (RF) signal in the form of an optical single sideband (OSSB) is generated by the photonic SSB frequency up-converter to solve the power fading problem caused by fiber chromatic dispersion. The generated OSSB RF signal has almost identical optical carrier power and optical sideband power. This SSB frequency up-conversion scheme shows an almost flat electrical RF power response as a function of the RF frequency in a range from 31 GHz to 75 GHz after 40 km single mode fiber (SMF) transmission. The photonic SSB frequency up-conversion technique shows negligible phase noise degradation. The phase noise of the up-converted RF signal at 49 GHz for an offset of 10 kHz is -93.17 dBc/Hz. Linearity analysis shows that the photonic SSB frequency up-converter has a spurious free dynamic range (SFDR) value of 79.51 dB · Hz(2/3). PMID:24514980

  6. Hydrothermal synthesis of hexagonal-phase NaYF4: Er, Yb with different shapes for application as photovoltaic up-converters

    Institute of Scientific and Technical Information of China (English)

    Wang Dong-Feng; Zhang Xiao-Dan; Liu Yong-Juan; Wu Chun-Ya; Zhang Cun-Shan; Wei Chang-Chun; Zhao Ying

    2013-01-01

    Hexagonalβ-NaYF4 co-doped with Yb3+ and Er3+ is directly synthesized under mild conditions using a hydrothermal method.The variation of the ratio of Ln3+ to F and ethylenediaminetetraacetic acid (EDTA) causes the shape of the microcrystal to change from microplate to microcolumn.The NaYF4 powder is mixed with polydimethylsiloxane (PDMS)to create an up-converter for thin film amorphous silicon solar cells so as to evaluate the effectiveness of the synthesized material as an up-converter.In order to overcome the difficulty in measuring the effectiveness of up-conversion material,a new method of using near infrared illumination to measure the short circuit current densities of solar cells both with and without up-converters is developed.An up-converter with pure hexagonal NaYF4:yb3+/Er3+ microcrystal produces a high current output.Emission intensity data obtained by photoluminescence suggest that pure hexagonal NaYF4:yb3+/Er3+ microcrystals are more efficient than nanocrystals when used as up-converting phosphors.

  7. A biocompatible magnetic film: synthesis and characterization

    OpenAIRE

    Chatterjee, Jhunu; Haik, Yousef; Chen, Ching Jen

    2004-01-01

    Background Biotechnology applications of magnetic gels include biosensors, targeted drug delivery, artificial muscles and magnetic buckles. These gels are produced by incorporating magnetic materials in the polymer composites. Methods A biocompatible magnetic gel film has been synthesized using polyvinyl alcohol. The magnetic gel was dried to generate a biocompatible magnetic film. Nanosized iron oxide particles (γ-Fe2O3, ~7 nm) have been used to produce the magnetic gel. Results The surface ...

  8. Biocompatible medical implant materials with binding sites for a biodegradable drug-delivery system

    Directory of Open Access Journals (Sweden)

    Al-Dubai H

    2011-10-01

    Full Text Available Haifa Al-Dubai1, Gisela Pittner1, Fritz Pittner1, Franz Gabor21Max F Perutz Laboratories, Department of Biochemistry, University of Vienna, Vienna, Austria; 2Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Life Sciences, University of Vienna, Vienna, AustriaAbstract: Feasibility studies have been carried out for development of a biocompatible coating of medical implant materials allowing the binding of biodegradable drug-delivery systems in a way that their reloading might be possible. These novel coatings, able to bind biodegradable nanoparticles, may serve in the long run as drug carriers to mediate local pharmacological activity. After biodegradation of the nanoparticles, the binding sites could be reloaded with fresh drug-delivering particles. As a suitable receptor system for the nanoparticles, antibodies are anchored. The design of the receptor is of great importance as any bio- or chemorecognitive interaction with other components circulating in the blood has to be avoided. Furthermore, the binding between receptor and the particles has to be strong enough to keep them tightly bound during their lifetime, but on the other hand allow reloading after final degradation of the particles. The nanoparticles suggested as a drug-delivery system for medical implants can be loaded with different pharmaceuticals such as antibiotics, growth factors, or immunosuppressives. This concept may enable the changing of medication, even after implantation of the medical device, if afforded by patients’ needs.Keywords: antibody immobilization, biocompatible coating, chitosan nanoparticles, drug targeting, medical device

  9. Synthetic cornea: biocompatibility and optics

    Science.gov (United States)

    Parel, Jean-Marie A.; Kaminski, Stefan; Fernandez, Viviana; Alfonso, E.; Lamar, Peggy; Lacombe, Emmanuel; Duchesne, Bernard; Dubovy, Sander; Manns, Fabrice; Rol, Pascal O.

    2002-06-01

    Purpose. Experimentally find a method to provide a safe surgical technique and an inexpensive and long lasting mesoplant for the restoration of vision in patients with bilateral corneal blindness due to ocular surface and stromal diseases. Methods. Identify the least invasive and the safest surgical technique for synthetic cornea implantation. Identify the most compatible biomaterials and the optimal shape a synthetic cornea must have to last a long time when implanted in vivo. Results. Penetrating procedures were deemed too invasive, time consuming, difficult and prone to long term complications. Therefore a non-penetrating delamination technique with central trephination was developed to preserve the integrity of Descemet's membrane and the anterior segment. Even though this approach limits the number of indications, it is acceptable since the majority of patients only have opacities in the stroma. The prosthesis was designed to fit in the removed tissue plane with its skirt fitted under the delaminated stroma. To improve retention, the trephination wall was made conical with the smallest opening on the anterior surface and a hat-shaped mesoplant was made to fit. The skirt was perforated in its perimeter to allow passage of nutrients and tissues ingrowths. To simplify the fabrication procedure, the haptic and optic were made of the same polymer. The intrastromal biocompatibility of several hydrogels was found superior to current clinically used PMMA and PTFE materials. Monobloc mesoplants made of 4 different materials were implanted in rabbits and followed weekly until extrusion occurred. Some remained optically clear allowing for fundus photography. Conclusions. Hydrogel synthetic corneas can be made to survive for periods longer than 1 year. ArF excimer laser photoablation studies are needed to determine the refractive correction potential of these mesoplants. A pilot FDA clinical trial is needed to assess the mesoplant efficacy and very long-term stability.

  10. Superparamagnetic iron oxide/chitosan core/shells for hyperthermia application: Improved colloidal stability and biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Patil, R.M.; Shete, P.B.; Thorat, N.D.; Otari, S.V. [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India); Barick, K.C.; Prasad, A.; Ningthoujam, R.S. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, MS (India); Tiwale, B.M. [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India); Pawar, S.H., E-mail: pawar_s_h@yahoo.com [Center for Interdisciplinary Research, D.Y. Patil University, Kolhapur 416006, MS (India)

    2014-04-15

    Superparamagnetic magnetite nanoparticles are of great interest due to their potential biomedical applications. In the present investigation, Fe{sub 3}O{sub 4} magnetic nanoparticles were prepared by alkaline precipitation using ferrous chloride as the sole source. An amphiphilic polyelectrolyte with the property of biocompatibility and functional carboxyl groups was used as a stabilizer to prepare a well-dispersed suspension of superparamagnetic Fe{sub 3}O{sub 4} nanoparticles. The final material composed of Fe{sub 3}O{sub 4} core and chitosan (CH) shell was produced. The amino groups of CH coated on Fe{sub 3}O{sub 4} nanoparticles were further cross linked using glutaraldehyde (GLD) for stable coating. FTIR spectra, XPS and TGA confirmed the coating of CH/GLD on the surface of Fe{sub 3}O{sub 4} nanoparticles. XRD patterns indicate the pure phase Fe{sub 3}O{sub 4} with a spinel structure. The nanoparticles were superparamagnetic at room temperature with saturation magnetization values for bare and coated nanoparticles which were 51.68 emu/g and 48.60 emu/g, respectively. Zeta potential values showed higher colloidal stability of coated nanoparticles than the bare one. Cytotoxicity study up to 2 mg mL{sup −1} concentration showed no drastic change in cell viability of nanoparticles after coating. Also, coated nanoparticles showed increased SAR value, making them suitable for hyperthermia therapy application. - Highlights: • Fe{sub 3}O{sub 4} nanoparticles were synthesized from FeCl{sub 2} as the sole source by alkaline precipitation. • Coating of Fe{sub 3}O{sub 4} nanoparticles was done with chitosan by simple ultrasonication. • Chitosan cross-linked with glutaraldehyde. • High colloidal stability was observed. • Increased SAR value and least cytotoxicity were observed.

  11. High Resolution Fluorescence Imaging of Cancers Using Lanthanide Ion-Doped Upconverting Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Naccache, Rafik; Rodríguez, Emma Martín; Bogdan, Nicoleta [Department of Chemistry and Biochemistry, Concordia University, Montreal H4B 1R6 (Canada); Sanz-Rodríguez, Francisco [Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Cruz, Maria del Carmen Iglesias de la [Departamento de Fisiología. Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029 (Spain); Fuente, Ángeles Juarranz de la [Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Vetrone, Fiorenzo [Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes J3X 1S2 (Canada); Jaque, Daniel; Solé, José García, E-mail: jose.garcia_sole@uam.es [Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Capobianco, John A., E-mail: jose.garcia_sole@uam.es [Department of Chemistry and Biochemistry, Concordia University, Montreal H4B 1R6 (Canada)

    2012-10-22

    During the last decade inorganic luminescent nanoparticles that emit visible light under near infrared (NIR) excitation (in the biological window) have played a relevant role for high resolution imaging of cancer. Indeed, semiconductor quantum dots (QDs) and metal nanoparticles, mostly gold nanorods (GNRs), are already commercially available for this purpose. In this work we review the role which is being played by a relatively new class of nanoparticles, based on lanthanide ion doped nanocrystals, to target and image cancer cells using upconversion fluorescence microscopy. These nanoparticles are insulating nanocrystals that are usually doped with small percentages of two different rare earth (lanthanide) ions: The excited donor ions (usually Yb{sup 3+} ion) that absorb the NIR excitation and the acceptor ions (usually Er{sup 3+}, Ho{sup 3+} or Tm{sup 3+}), that are responsible for the emitted visible (or also near infrared) radiation. The higher conversion efficiency of these nanoparticles in respect to those based on QDs and GNRs, as well as the almost independent excitation/emission properties from the particle size, make them particularly promising for fluorescence imaging. The different approaches of these novel nanoparticles devoted to “in vitro” and “in vivo” cancer imaging, selective targeting and treatment are examined in this review.

  12. High Resolution Fluorescence Imaging of Cancers Using Lanthanide Ion-Doped Upconverting Nanocrystals

    International Nuclear Information System (INIS)

    During the last decade inorganic luminescent nanoparticles that emit visible light under near infrared (NIR) excitation (in the biological window) have played a relevant role for high resolution imaging of cancer. Indeed, semiconductor quantum dots (QDs) and metal nanoparticles, mostly gold nanorods (GNRs), are already commercially available for this purpose. In this work we review the role which is being played by a relatively new class of nanoparticles, based on lanthanide ion doped nanocrystals, to target and image cancer cells using upconversion fluorescence microscopy. These nanoparticles are insulating nanocrystals that are usually doped with small percentages of two different rare earth (lanthanide) ions: The excited donor ions (usually Yb3+ ion) that absorb the NIR excitation and the acceptor ions (usually Er3+, Ho3+ or Tm3+), that are responsible for the emitted visible (or also near infrared) radiation. The higher conversion efficiency of these nanoparticles in respect to those based on QDs and GNRs, as well as the almost independent excitation/emission properties from the particle size, make them particularly promising for fluorescence imaging. The different approaches of these novel nanoparticles devoted to “in vitro” and “in vivo” cancer imaging, selective targeting and treatment are examined in this review

  13. Conjugated polymer nanoparticles

    Science.gov (United States)

    Tuncel, Dönüs; Demir, Hilmi Volkan

    2010-04-01

    Conjugated polymer nanoparticles are highly versatile nano-structured materials that can potentially find applications in various areas such as optoelectronics, photonics, bio-imaging, bio-sensing and nanomedicine. Their straightforward synthesis in desired sizes and properties, biocompatibility and non-toxicity make these materials highly attractive for the aforementioned applications. This feature article reviews the recent developments in the synthesis, characterization, properties and application of these exciting nanostructured materials.

  14. Nanoparticles from Renewable Polymers

    Directory of Open Access Journals (Sweden)

    Frederik Roman Wurm

    2014-07-01

    Full Text Available The use of polymers from natural resources can bring many benefits for novel polymeric nanoparticle systems. Such polymers have a variety of beneficial properties such as biodegradability and biocompatibility, they are readily available on large scale and at low cost. As the amount of fossil fuels decrease, their application becomes more interesting even if characterization is in many cases more challenging due to structural complexity, either by broad distribution of their molecular weights polysaccharides, polyesters, lignin or by complex structure (proteins, lignin. This review summarizes different sources and methods for the preparation of biopolymer-based nanoparticle systems for various applications.

  15. Irradiation stability and cytotoxicity of gold nanoparticles for radiotherapy

    OpenAIRE

    Zhang, Xiao-Dong; Guo, Mei-Li; Wu, Hong-Ying; Sun, Yuan-Ming; Ding, Yan-Qiu; Feng, Xin; Zhang, Liang-An

    2009-01-01

    Gold nanoparticles are promising as a kind of novel radiosensitizer in radiotherapy. If gold nanoparticles are shown to have good irradiation stability and biocompatibility, they would play an important role in radiotherapy. In this work, we investigated irradiation effects of gold nanoparticles under 2–10 kR gamma irradiation and cytotoxicity of gold nanoparticles with human K562 cells by using Cell Titre-Glo™ luminescent cell viability assay. The results revealed that gamma irradiation had ...

  16. Extracting Short Rise-Time Velocity Profiles with Digital Down-Shift Analysis of Optically Up-Converted PDV Data

    International Nuclear Information System (INIS)

    This work describes the digital down-shift (DDS) technique, a new method of extracting short rise-time velocity profiles in the analysis of optically up-converted PDV data. The DDS technique manipulates the PDV data by subtracting a constant velocity (i.e., the DDS velocity νDDS) from the velocity profile. DDS exploits the simple fact that the optically up-converted data ride on top of a base velocity (ν0, the apparent velocity at no motion) with a rapid rise to a high velocity (νf) of a few km/s or more. Consequently, the frequency content of the signal must describe a velocity profile that increases from ν0 to ν0 + νf. The DDS technique produces velocity reversals in the processed data before shock breakout when ν0 < νDDS < ν0 + νf. The DDS analysis process strategically selects specific DDS velocities (velocity at which the user down shifts the data) that produce anomalous reversals (maxima and/or minima), which are predictable and easy to identify in the mid-range of the data. Additional analysis determines when these maxima and minima occur. By successive application of the DDS technique and iterative analysis, velocity profiles are extracted as time as a function of velocity rather than as a function of time as it would be in a conventional velocity profile. Presented results include a description of DDS, velocity profiles extracted from laser-driven shock data with rise times of 200 ps or less, and a comparison with other techniques.

  17. Extracting Short Rise-Time Velocity Profiles with Digital Down-Shift Analysis of Optically Up-Converted PDV Data

    Energy Technology Data Exchange (ETDEWEB)

    Abel Diaz, Nathan Riley, Cenobio Gallegos, Matthew Teel, Michael Berninger, Thomas W. Tunnell

    2010-09-08

    This work describes the digital down-shift (DDS) technique, a new method of extracting short rise-time velocity profiles in the analysis of optically up-converted PDV data. The DDS technique manipulates the PDV data by subtracting a constant velocity (i.e., the DDS velocity νDDS) from the velocity profile. DDS exploits the simple fact that the optically up-converted data ride on top of a base velocity (ν0, the apparent velocity at no motion) with a rapid rise to a high velocity (νf) of a few km/s or more. Consequently, the frequency content of the signal must describe a velocity profile that increases from ν0 to ν0 + νf. The DDS technique produces velocity reversals in the processed data before shock breakout when ν0 < νDDS < ν0 + νf. The DDS analysis process strategically selects specific DDS velocities (velocity at which the user down shifts the data) that produce anomalous reversals (maxima and/or minima), which are predictable and easy to identify in the mid-range of the data. Additional analysis determines when these maxima and minima occur. By successive application of the DDS technique and iterative analysis, velocity profiles are extracted as time as a function of velocity rather than as a function of time as it would be in a conventional velocity profile. Presented results include a description of DDS, velocity profiles extracted from laser-driven shock data with rise times of 200 ps or less, and a comparison with other techniques.

  18. A multifunctional upconverting nanoparticle incorporated polycationic hydrogel for near-infrared triggered and synergistic treatment of drug-resistant bacteria

    Science.gov (United States)

    Yin, Meili; Li, Zhenhua; Zhou, Li; Dong, Kai; Ren, Jinsong; Qu, Xiaogang

    2016-03-01

    Recently, antibiotic drug-resistant therapies have become very important due to the emergence of antibiotic-resistant bacterial strains. The development of novel antibacterial materials has received significant attention. Here, quaternized chitosan hydrogels incorporated with NaYF4:Er/Yb/Mn@photosensitizer-doped silica (UCNPs/MB) were synthesized for effective killing of both gram-positive oxacillin-resistant S. aureus (DR-S. aureus) and gram-negative kanamyclin-resistant E. coli (DR-E. coli) bacteria upon near-infrared (NIR) laser irradiation. In this system, the cationic macroporous nature of the hydrogel acts as a molecular ‘anion sponge’, which sucks the outer part of the anionic microbe membrane into the gel interior voids and causes microbe membrane disruption. By incorporating UCNPs/MB-doped silica into the hydrogel, we have combined photodynamic therapy (PDT) with quaternized chitosan to obtain a high therapeutic index via a synergistic effect. In vitro experiments have demonstrated that our system had excellent antibacterial efficiency to both DR-S. aureus and DR-E. coli bacteria. More importantly, our new synergistic treatment modality provided an excellent therapy platform for drug-resistant bacteria, which could improve antimicrobial efficiency.

  19. Microemulsion Synthesis of Nanoparticles

    Directory of Open Access Journals (Sweden)

    Gotić, M.

    2013-11-01

    toxicity of the nanoparticles and increase their biocompatibility, and the functional groups on the surface enable specific applications in biomedicine. Microemulsion synthesis is convenient both for organic and polymer particles. Polymerization or crosslinking reactions may be initiated in the water core of microaggregates by using chemicals, UV or ionizing radiation (Fig. 3. Microemulsion polymerization is advantageous due to fast reactions, uniform particle size, great stability and high polymerization degree. Magnetite nanoparticles induce great interest due to biomedical applications. Magnetite is a biocompatible material that may be prepared in the form of well-dispersed nanoparticles smaller than 4 nm, which are not recognized by the immune system. The authors’ own approach for the synthesis of magnetite nanoparticles using g-irradiation assisted microemulsion technique is described (Figs. 5–10.

  20. Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization.

    Science.gov (United States)

    Landgraf, Lisa; Müller, Ines; Ernst, Peter; Schäfer, Miriam; Rosman, Christina; Schick, Isabel; Köhler, Oskar; Oehring, Hartmut; Breus, Vladimir V; Basché, Thomas; Sönnichsen, Carsten; Tremel, Wolfgang; Hilger, Ingrid

    2015-01-01

    In the research field of nanoparticles, many studies demonstrated a high impact of the shape, size and surface charge, which is determined by the functionalization, of nanoparticles on cell viability and internalization into cells. This work focused on the comparison of three different nanoparticle types to give a better insight into general rules determining the biocompatibility of gold, Janus and semiconductor (quantum dot) nanoparticles. Endothelial cells were subject of this study, since blood is the first barrier after intravenous nanoparticle application. In particular, stronger effects on the viability of endothelial cells were found for nanoparticles with an elongated shape in comparison to spherical ones. Furthermore, a positively charged nanoparticle surface (NH2, CyA) leads to the strongest reduction in cell viability, whereas neutral and negatively charged nanoparticles are highly biocompatible to endothelial cells. These findings are attributed to a rapid internalization of the NH2-functionalized nanoparticles in combination with the damage of intracellular membranes. Interestingly, the endocytotic pathway seems to be a size-dependent process whereas nanoparticles with a size of 20 nm are internalized by caveolae-mediated endocytosis and nanoparticles with a size of 40 nm are taken up by clathrin-mediated internalization and macropinocytosis. Our results can be summarized to formulate five general rules, which are further specified in the text and which determine the biocompatibility of nanoparticles on endothelial cells. Our findings will help to design new nanoparticles with optimized properties concerning biocompatibility and uptake behavior with respect to the respective intended application. PMID:25821668

  1. Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

    Directory of Open Access Journals (Sweden)

    Lisa Landgraf

    2015-01-01

    Full Text Available In the research field of nanoparticles, many studies demonstrated a high impact of the shape, size and surface charge, which is determined by the functionalization, of nanoparticles on cell viability and internalization into cells. This work focused on the comparison of three different nanoparticle types to give a better insight into general rules determining the biocompatibility of gold, Janus and semiconductor (quantum dot nanoparticles. Endothelial cells were subject of this study, since blood is the first barrier after intravenous nanoparticle application. In particular, stronger effects on the viability of endothelial cells were found for nanoparticles with an elongated shape in comparison to spherical ones. Furthermore, a positively charged nanoparticle surface (NH2, CyA leads to the strongest reduction in cell viability, whereas neutral and negatively charged nanoparticles are highly biocompatible to endothelial cells. These findings are attributed to a rapid internalization of the NH2-functionalized nanoparticles in combination with the damage of intracellular membranes. Interestingly, the endocytotic pathway seems to be a size-dependent process whereas nanoparticles with a size of 20 nm are internalized by caveolae-mediated endocytosis and nanoparticles with a size of 40 nm are taken up by clathrin-mediated internalization and macropinocytosis. Our results can be summarized to formulate five general rules, which are further specified in the text and which determine the biocompatibility of nanoparticles on endothelial cells. Our findings will help to design new nanoparticles with optimized properties concerning biocompatibility and uptake behavior with respect to the respective intended application.

  2. Biocompatibility and Stability of Polysaccharide Polyelectrolyte Complexes Aimed at Respiratory Delivery

    Directory of Open Access Journals (Sweden)

    Susana Rodrigues

    2015-08-01

    Full Text Available Chitosan (CS and chondroitin sulfate (CHS are natural polymers with demonstrated applicability in drug delivery, while nanoparticles are one of the most explored carriers for transmucosal delivery of biopharmaceuticals. In this work we have prepared CS/CHS nanoparticles and associated for the first time the therapeutic protein insulin. Fluorescein isothiocyanate bovine serum albumin (FITC-BSA was also used to enable comparison of behaviors regarding differences in molecular weight (5.7 kDa versus 67 kDa. Nanoparticles of approximately 200 nm and positive zeta potential around +20 mV were obtained. These parameters remained stable for up to 1 month at 4 °C. Proteins were associated with efficiencies of more than 50%. The release of FITC-BSA in PBS pH 7.4 was more sustained (50% in 24 h than that of insulin (85% in 24 h. The biocompatibility of nanoparticles was tested in Calu-3 and A549 cells by means of three different assays. The metabolic assay MTT, the determination of lactate dehydrogenase release, and the quantification of the inflammatory response generated by cell exposure to nanoparticles have indicated an absence of overt toxicity. Overall, the results suggest good indications on the application of CS/CHS nanoparticles in respiratory transmucosal protein delivery, but the set of assays should be widened to clarify obtained results.

  3. Preparation of 2 nm gold nanoparticles for in vitro and in vivo applications

    OpenAIRE

    Moyano, Daniel F.; Duncan, Bradley; Rotello, Vincent M.

    2013-01-01

    Gold nanoparticles have been a versatile tool in recent years for the exploration of biological systems. However, challenges with purification and adequate surface coverage limit the biocompatibility of gold nanoparticles. Here, we describe a detailed procedure for the synthesis, purification, and functionalization of biologically compatible gold nanoparticles for in vitro and in vivo studies.

  4. In vivo biocompatibility of porous silicon biomaterials for drug delivery to the heart.

    Science.gov (United States)

    Tölli, Marja A; Ferreira, Mónica P A; Kinnunen, Sini M; Rysä, Jaana; Mäkilä, Ermei M; Szabó, Zoltán; Serpi, Raisa E; Ohukainen, Pauli J; Välimäki, Mika J; Correia, Alexandra M R; Salonen, Jarno J; Hirvonen, Jouni T; Ruskoaho, Heikki J; Santos, Hélder A

    2014-09-01

    Myocardial infarction (MI), commonly known as a heart attack, is the irreversible necrosis of heart muscle secondary to prolonged ischemia, which is an increasing problem in terms of morbidity, mortality and healthcare costs worldwide. Along with the idea to develop nanocarriers that efficiently deliver therapeutic agents to target the heart, in this study, we aimed to test the in vivo biocompatibility of different sizes of thermally hydrocarbonized porous silicon (THCPSi) microparticles and thermally oxidized porous silicon (TOPSi) micro and nanoparticles in the heart tissue. Despite the absence or low cytotoxicity, both particle types showed good in vivo biocompatibility, with no influence on hematological parameters and no considerable changes in cardiac function before and after MI. The local injection of THCPSi microparticles into the myocardium led to significant higher activation of inflammatory cytokine and fibrosis promoting genes compared to TOPSi micro and nanoparticles; however, both particles showed no significant effect on myocardial fibrosis at one week post-injection. Our results suggest that THCPSi and TOPSi micro and nanoparticles could be applied for cardiac delivery of therapeutic agents in the future, and the PSi biomaterials might serve as a promising platform for the specific treatment of heart diseases.

  5. Nanotoxicology and nanoparticle safety in biomedical designs

    Directory of Open Access Journals (Sweden)

    Ai J

    2011-05-01

    Full Text Available Jafar Ai1, Esmaeil Biazar2, Mostafa Jafarpour3, Mohamad Montazeri4, Ali Majdi5, Saba Aminifard5, Mandana Zafari5, Hanie Akbari R6, Hadi Rad Gh71Department of Tissue Engineering, Faculty of Advanced Technologies, Tehran University of Medical Sciences, Tehran; 2Department of Chemistry, Islamic Azad University – Tonekabon Branch, Mazandaran; 3Department of Microbiology, Faculty of Science, Islamic Azad University – Tonekabon Branch, Mazandaran; 4Faculty of Medical Sciences, Babol University of Medical Sciences; 5Young Researchers Club – Islamic Azad University, Tonekabon Branch, Mazandaran; 6Faculty of Medical Sciences, Islamic Azad University – North branch, Tehran; 7Faculty of Medical Sciences, Islamic Azad University – Tonekabon Branch, Mazandaran, IranAbstract: Nanotechnology has wide applications in many fields, especially in the biological sciences and medicine. Nanomaterials are applied as coating materials or in treatment and diagnosis. Nanoparticles such as titania, zirconia, silver, diamonds, iron oxides, carbon nanotubes, and biodegradable polymers have been studied in diagnosis and treatment. Many of these nanoparticles may have toxic effects on cells. Many factors such as size, inherent properties, and surface chemistry may cause nanoparticle toxicity. There are methods for improving the performance and reducing toxicity of nanoparticles in medical design, such as biocompatible coating materials or biodegradable/biocompatible nanoparticles. Most metal oxide nanoparticles show toxic effects, but no toxic effects have been observed with biocompatible coatings. Biodegradable nanoparticles are also used in the efficient design of medical materials, which will be reviewed in this article.Keywords: nanotechnology, nanotoxicology, nanomaterials, nanobiomaterials

  6. Cellular interactions of lauric acid and dextran-coated magnetite nanoparticles

    Science.gov (United States)

    Pradhan, Pallab; Giri, Jyotsnendu; Banerjee, Rinti; Bellare, Jayesh; Bahadur, Dhirendra

    2007-04-01

    In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.

  7. Cellular interactions of lauric acid and dextran-coated magnetite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, Pallab [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Giri, Jyotsnendu [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400076 (India); Banerjee, Rinti [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Bellare, Jayesh [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Bahadur, Dhirendra [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400076 (India)]. E-mail: dhirenb@iitb.ac.in

    2007-04-15

    In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.

  8. Responsive foams for nanoparticle delivery.

    Science.gov (United States)

    Tang, Christina; Xiao, Edward; Sinko, Patrick J; Szekely, Zoltan; Prud'homme, Robert K

    2015-09-01

    We have developed responsive foam systems for nanoparticle delivery. The foams are easy to make, stable at room temperature, and can be engineered to break in response to temperature or moisture. Temperature-responsive foams are based on the phase transition of long chain alcohols and could be produced using medical grade nitrous oxide as a propellant. These temperature-sensitive foams could be used for polyacrylic acid (PAA)-based nanoparticle delivery. We also discuss moisture-responsive foams made with soap pump dispensers. Polyethylene glycol (PEG)-based nanoparticles or PMMA latex nanoparticles were loaded into Tween 20 foams and the particle size was not affected by the foam formulation or foam break. Using biocompatible detergents, we anticipate this will be a versatile and simple approach to producing foams for nanoparticle delivery with many potential pharmaceutical and personal care applications. PMID:26091943

  9. Biocompatibility of prosthodontic materials and test methods

    OpenAIRE

    İrem Türkcan; Asude Dilek Nalbant

    2016-01-01

    Various materials with different features and content are widely used in dentistry. While fulfilling their aesthetic and functional tasks, these materials are in contact with oral tissues and fluids. Therefore, besides physical and mechanical properties, biocompatibility also is a required property for these materials. Biomaterials are non-vital materials placed on or inside the human body, and interact with biological systems. Dental materials placed in the mouth are also considered as bioma...

  10. Biocompatibility and osteogenic properties of porous tantalum

    OpenAIRE

    Wang, Qian; Zhang, Hui; LI, QIJIA; Ye,Lei; GAN, HONGQUAN; Liu, Yingjie; Wang, Hui; Wang, Zhiqiang

    2015-01-01

    Porous tantalum has been reported to be a promising material for use in bone tissue engineering. In the present study, the biocompatibility and osteogenic properties of porous tantalum were studied in vitro and in vivo. The morphology of porous tantalum was observed using scanning electron microscopy (SEM). Osteoblasts were cultured with porous tantalum, and cell morphology, adhesion and proliferation were investigated using optical microscopy and SEM. In addition, porous tantalum rods were i...

  11. Carbon nanoparticles downregulate expression of basic fibroblast growth factor in the heart during embryogenesis

    DEFF Research Database (Denmark)

    Wierzbicki, Mateusz; Sawosz, Ewa; Grodzik, Marta;

    2013-01-01

    Carbon nanoparticles, with their high biocompatibility and low toxicity, have recently been considered for biomedical applications, including antiangiogenic therapy. Critical to normal development and tumor formation, angiogenesis is the process of forming capillary blood vessels from preexisting...

  12. Large-scale production and characterization of biocompatible colloidal nanoalumina.

    Science.gov (United States)

    Razali, W A W; Sreenivasan, V K A; Goldys, E M; Zvyagin, A V

    2014-12-23

    The rapid uptake of nanomaterials in life sciences calls for the development of universal, high-yield techniques for their production and interfacing with biomolecules. Top-down methods take advantage of the existing variety of bulk and thin-film solid-state materials for improved prediction and control of the resultant nanomaterial properties. We demonstrate the power of this approach using high-energy ball milling (HEBM) of alumina (Al2O3). Nanoalumina particles with a mean size of 25 nm in their most stable α-crystallographic phase were produced in gram quantities, suitable for biological and biomedical applications. Nanomaterial contamination from zirconia balls used in HEBM was reduced from 19 to 2% using a selective acid etching procedure. The biocompatibility of the milled nanomaterial was demonstrated by forming stable colloids in water and physiological buffers, corroborated by zeta potentials of +40 mV and -40 mV and characterized by in vitro cytotoxicity assays. Finally, the feasibility of a milled nanoalumina surface in anchoring a host of functional groups and biomolecules was demonstrated by the functionalization of their surface using facile silane chemistry, resulting in the decoration of the nanoparticle surface with amino groups suitable for further conjugation of biomolecules. PMID:25434921

  13. Plasma polymerized carvone as an antibacterial and biocompatible coating.

    Science.gov (United States)

    Chan, Yuen Wah; Siow, Kim Shyong; Ng, Pei Yuen; Gires, Usup; Yeop Majlis, Burhanuddin

    2016-11-01

    Antibacterial coating is important to prevent the colonization of medical devices by biofilm forming bacteria that would cause infection and sepsis in patients. Current coating techniques such as immobilization of antimicrobial compounds, time-releasing antibiotic agents and silver nanoparticles, require multiple processing steps, and they have low efficacy and low stability. We proposed a single-step plasma polymerization of an essential oil known as carvone to produce a moderately hydrophobic antibacterial coating (ppCar) with an average roughness of static water contact angle of 78°, even after 10days of air aging and it maintained its stability throughout 24h of LB broth immersion. ppCar showed promising results in the live-dead fluorescence assay and crystal violet assay. The biofilm assay showed an effective reduction of E. coli and S. aureus bacteria by 86% and 84% respectively. ppCar is also shown to rupture the bacteria membrane for its bactericidal effects. The cytotoxicity test indicated that the coating is not cytotoxic to the human cell line. This study would be of interest to researcher keen on producing a bacteria-resistance and biocompatible coating on different substrates in a cost-effective manner. PMID:27524089

  14. A handy-motion driven, frequency up-converted hybrid vibration energy harvester using PZT bimorph and nonmagnetic ball

    Science.gov (United States)

    Halim, M. A.; Cho, H. O.; Park, J. Y.

    2014-11-01

    We have presented a frequency up-converted hybrid type (Piezoelectric and Electromagnetic) vibration energy harvester that can be used in powering portable and wearable smart devices by handy motion. A transverse impact mechanism has been employed for frequency up-conversion. Use of two transduction mechanisms increases the output power as well as power density. The proposed device consists of a non-magnetic spherical ball (freely movable at handy motion frequency) to impact periodically on the parabolic top of a piezoelectric (PZT) cantilevered mass by sliding over it, allowing it to vibrate at its higher resonant frequency and generates voltage by virtue of piezoelectric effect. A magnet attached to the cantilever vibrates along with it at the same frequency and a relative motion between the magnet and a coil placed below it, induces emf voltage across the coil terminals as well. A macro-scale prototype of the harvester has been fabricated and tested by handy motion. With an optimum magnet-coil overlap, a maximum 0.98mW and 0.64mW peak powers have been obtained from the piezoelectric and the electromagnetic transducers of the proposed device while shaken, respectively. It offers 84.4μWcm-3 peak power density.

  15. Giant Two-Photon Absorption Coefficient and Frequency Up-Converted Luminescence in Monolayer MoS2

    CERN Document Server

    Li, Yuanxin; Zhang, Saifeng; Zhang, Xiaoyan; Feng, Yanyan; Wang, Kangpeng; Zhang, Long; Wang, Jun

    2015-01-01

    Strong two-photon absorption (TPA) in monolayer MoS2 is demonstrated in contrast to saturable absorption (SA) in multilayer MoS2 under the excitation of femtosecond laser pulses in the near infrared region. MoS2 in the forms of monolayer single crystal and multilayer triangular islands are grown on either quartz or SiO2/Si by employing the seeding method through chemistry vapor deposition. The nonlinear transmission measurements reveal that monolayer MoS2 possesses a giant nonsaturation TPA coefficient, larger than that of conventional semiconductors. As a result of TPA, two-photon pumped frequency up-converted luminescence is observed directly in the monolayer MoS2. For the multilayer MoS2, the SA response is demonstrated with the ratio of the excited-state absorption cross section to ground-state cross section of 0.18. In addition, the laser damage threshold of the monolayer MoS2 is 97 GW/cm2, larger than that of the multilayer MoS2 of 78 GW/cm2.

  16. Up-converted ultraviolet luminescence of Er3+:BaGd2ZnO5 phosphors for healthy illumination

    Science.gov (United States)

    Zhang, Ya; Cui, Qingzhi; Wang, Zhanyong; Liu, Gan; Tian, Tian; Xu, Jiayue

    2016-09-01

    Moderate level of exposure to the solar irradiation containing UV component is essential for health care. To incorporate the UV-emitting phosphors into the commercial YAG-based white light-emitting diode introduces the possibilities of healthy illumination to individuals' daily lives. 1 mol.% Er3+-doped BaGd2ZnO5 (BGZ) particles were synthesized via sol-gel method and efficient up-converted luminescence peaked at 380 nm was detected under 480 nm excitation. The mixed phosphors with varied mass ratio of Er3+:BGZ and Ce3+:YAG particles were encapsulated to form LEDs. The study of the LEDs indicated that the introduction of BGZ component favored the enhancement of color-rendering index and the neutralization of the white light emitting. The WLED with the BGZ/YAG ratio of 8:2 was recommendable for its excellent overall white light luminous performances and UV intensity of 84.55 mW/cm2. The UV illumination dose of the WLEDs with mixed YAG and BGZ was controllable by adjusting the ratio, the illumination distance and the illumination time. Er3+:BGZ phosphors are promising UVemitting phosphors for healthy indoor illumination.

  17. In vivo biocompatibility, clearance, and biodistribution of albumin vehicles for pulmonary drug delivery.

    Science.gov (United States)

    Woods, A; Patel, A; Spina, D; Riffo-Vasquez, Y; Babin-Morgan, A; de Rosales, R T M; Sunassee, K; Clark, S; Collins, H; Bruce, K; Dailey, L A; Forbes, B

    2015-07-28

    The development of clinically acceptable albumin-based nanoparticle formulations for use in pulmonary drug delivery has been hindered by concerns about the toxicity of nanomaterials in the lungs combined with a lack of information on albumin nanoparticle clearance kinetics and biodistribution. In this study, the in vivo biocompatibility of albumin nanoparticles was investigated following a single administration of 2, 20, and 390μg/mouse, showing no inflammatory response (TNF-α and IL-6, cellular infiltration and protein concentration) compared to vehicle controls at the two lower doses, but elevated mononucleocytes and a mild inflammatory effect at the highest dose tested. The biodistribution and clearance of (111)In labelled albumin solution and nanoparticles over 48h following a single pulmonary administration to mice was investigated by single photon emission computed tomography and X-ray computed tomography imaging and terminal biodistribution studies. (111)In labelled albumin nanoparticles were cleared more slowly from the mouse lung than (111)In albumin solution (64.1±8.5% vs 40.6±3.3% at t=48h, respectively), with significantly higher (P24h indicating that small amounts of activity were cleared from the lungs both by translocation across the lung mucosal barrier, as well as mucociliary clearance. This study provides important information on the fate of albumin vehicles in the lungs, which may be used to direct future formulation design of inhaled nanomedicines.

  18. Biomimetic, mild chemical synthesis of CdTe-GSH quantum dots with improved biocompatibility.

    Directory of Open Access Journals (Sweden)

    José M Pérez-Donoso

    Full Text Available Multiple applications of nanotechnology, especially those involving highly fluorescent nanoparticles (NPs or quantum dots (QDs have stimulated the research to develop simple, rapid and environmentally friendly protocols for synthesizing NPs exhibiting novel properties and increased biocompatibility. In this study, a simple protocol for the chemical synthesis of glutathione (GSH-capped CdTe QDs (CdTe-GSH resembling conditions found in biological systems is described. Using only CdCl(2, K(2TeO(3 and GSH, highly fluorescent QDs were obtained under pH, temperature, buffer and oxygen conditions that allow microorganisms growth. These CdTe-GSH NPs displayed similar size, chemical composition, absorbance and fluorescence spectra and quantum yields as QDs synthesized using more complicated and expensive methods.CdTe QDs were not freely incorporated into eukaryotic cells thus favoring their biocompatibility and potential applications in biomedicine. In addition, NPs entry was facilitated by lipofectamine, resulting in intracellular fluorescence and a slight increase in cell death by necrosis. Toxicity of the as prepared CdTe QDs was lower than that observed with QDs produced by other chemical methods, probably as consequence of decreased levels of Cd(+2 and higher amounts of GSH. We present here the simplest, fast and economical method for CdTe QDs synthesis described to date. Also, this biomimetic protocol favors NPs biocompatibility and helps to establish the basis for the development of new, "greener" methods to synthesize cadmium-containing QDs.

  19. The biocompatibility of fluorescent nanodiamonds and their mechanism of cellular uptake

    Science.gov (United States)

    Vaijayanthimala, Vairakkannu; Tzeng, Yan-Kai; Chang, Huan-Cheng; Li, Chung-Leung

    2009-10-01

    The labeling of cells with fluorescent nanoparticles is promising for various biomedical applications. The objective of this study is to evaluate the biocompatibility and the mechanism of the cellular uptake of fluorescent nanodiamonds (FNDs) in cancer cells (HeLa) and pre-adipocytes (3T3-L1). With flow cytometry and the use of a battery of metabolic and cytoskeletal inhibitors, we found that the mechanism of the FND uptake in both cells is by energy-dependent clathrin-mediated endocytosis. In addition, the surface charge of FND influences its cellular uptake, as the uptake of poly-L-lysine-coated FNDs is better than that of oxidative-acid-purified FNDs at the same concentration in regular medium with or without serum. We also confirm that the proliferative potential of FND-treated and untreated cells does not exhibit any significant differences when measured at bulk cultures, and more stringently at clonal cell density. Further biocompatibility studies indicate that the in vitro differentiation of 3T3-L1 pre-adipocytes and 489-2 osteoprogenitors is not affected by the FND treatment. Our results show that FNDs are biocompatible and ideal candidates for potential applications in human stem cell research.

  20. Safety of Nanoparticles in Medicine.

    Science.gov (United States)

    Wolfram, Joy; Zhu, Motao; Yang, Yong; Shen, Jianliang; Gentile, Emanuela; Paolino, Donatella; Fresta, Massimo; Nie, Guangjun; Chen, Chunying; Shen, Haifa; Ferrari, Mauro; Zhao, Yuliang

    2015-01-01

    Nanomedicine involves the use of nanoparticles for therapeutic and diagnostic purposes. During the past two decades, a growing number of nanomedicines have received regulatory approval and many more show promise for future clinical translation. In this context, it is important to evaluate the safety of nanoparticles in order to achieve biocompatibility and desired activity. However, it is unwarranted to make generalized statements regarding the safety of nanoparticles, since the field of nanomedicine comprises a multitude of different manufactured nanoparticles made from various materials. Indeed, several nanotherapeutics that are currently approved, such as Doxil and Abraxane, exhibit fewer side effects than their small molecule counterparts, while other nanoparticles (e.g. metallic and carbon-based particles) tend to display toxicity. However, the hazardous nature of certain nanomedicines could be exploited for the ablation of diseased tissue, if selective targeting can be achieved. This review discusses the mechanisms for molecular, cellular, organ, and immune system toxicity, which can be observed with a subset of nanoparticles. Strategies for improving the safety of nanoparticles by surface modification and pretreatment with immunomodulators are also discussed. Additionally, important considerations for nanoparticle safety assessment are reviewed. In regards to clinical application, stricter regulations for the approval of nanomedicines might not be required. Rather, safety evaluation assays should be adjusted to be more appropriate for engineered nanoparticles. PMID:26601723

  1. Chemical sensing and imaging based on photon upconverting nano- and microcrystals: a review

    Science.gov (United States)

    Christ, Simon; Schäferling, Michael

    2015-09-01

    The demand for photostable luminescent reporters that absorb and emit light in the red to near-infrared (NIR) spectral region continues in biomedical research and bioanalysis. In recent years, classical organic fluorophores have increasingly been displaced by luminescent nanoparticles. These consist of either polymer or silica based beads that are loaded with luminescent dyes, conjugated polymers, or inorganic nanomaterials such as semiconductor nanocrystals (quantum dots), colloidal clusters of silver and gold, or carbon dots. Among the inorganic materials, photon upconversion nanocrystals exhibit a high potential for application to bioimaging or biomolecular assays. They offer an exceptionally high photostability, can be excited in the NIR, and their anti-Stokes emission enables luminescence detection free of background and perturbing scatter effects even in complex biological samples. These lanthanide doped inorganic crystals have multiple emission lines that can be tuned by the selection of the dopants. This review article is focused on the applications of functionalized photon upconversion nanoparticles (UCNPs) to chemical sensing. This is a comparatively new field of research activity and mainly directed at the sensing and imaging of ubiquitous chemical analytes in biological samples, particularly in living cells. For this purpose, the particles have to be functionalized with suitable indicator dyes or recognition elements, as they do not show an intrinsic or specific luminescence response to most of these analytes (e.g. pH, oxygen, metal ions). We describe the strategies for the design of such responsive nanocomposites utilizing either luminescence resonance energy transfer or emission-reabsorption (inner filter effect) mechanisms and also highlight examples for their use either immobilized in sensor layers or directly as nanoprobes for intracellular sensing and imaging.

  2. Titanium nanostructural surface processing for improved biocompatibility

    International Nuclear Information System (INIS)

    X-ray photoelectron spectroscopy, grazing incident x-ray diffraction, transmission electron microscopy, and scanning electron microscopy were conducted to evaluate the effect of titanium hydride on the formation of nanoporous TiO2 on Ti during anodization. Nano-titanium-hydride was formed cathodically before anodizing and served as a sacrificial nanoprecipitate during anodization. Surface oxidation occurred and a multinanoporous structure formed after cathodic pretreatments followed by anodization treatment. The sacrificial nanoprecipitate is directly dissolved and the Ti transformed to nanoporous TiO2 by anodization. The formation of sacrificial nanoprecipitates by cathodic pretreatment and of the multinanostructure by anodization is believed to improve biocompatibility, thereby promoting osseointegration

  3. Fluorescent nanoparticles based on AIE fluorogens for bioimaging

    Science.gov (United States)

    Yan, Lulin; Zhang, Yan; Xu, Bin; Tian, Wenjing

    2016-01-01

    Fluorescent nanoparticles (FNPs) have recently attracted increasing attention in the biomedical field because of their unique optical properties, easy fabrication and outstanding performance in imaging. Compared with conventional molecular probes including small organic dyes and fluorescent proteins, FNPs based on aggregation-induced emission (AIE) fluorogens have shown significant advantages in tunable emission and brightness, good biocompatibility, superb photo- and physical stability, potential biodegradability and facile surface functionalization. In this review, we summarize the latest advances in the development of fluorescent nanoparticles based on AIE fluorogens including polymer nanoparticles and silica nanoparticles over the past few years, and the various biomedical applications based on these fluorescent nanoparticles are also elaborated.

  4. Biomedical Nanoparticles: Overview of Their Surface Immune-Compatibility

    OpenAIRE

    Olimpia Gamucci; Alice Bertero; Mariacristina Gagliardi; Giuseppe Bardi

    2014-01-01

    Diagnostic- and therapeutic release-aimed nanoparticles require the highest degree of biocompatibility. Some physical and chemical characteristics of such nanomaterials are often at odds with this requirement. For instance, metals with specific features used as contrast agents in magnetic resonance imaging need particular coatings to improve their blood solubility and increase their biocompatibility. Other examples come from the development of nanocarriers exploiting the different characteris...

  5. Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

    OpenAIRE

    Lisa Landgraf; Ines Müller; Peter Ernst; Miriam Schäfer; Christina Rosman; Isabel Schick; Oskar Köhler; Hartmut Oehring; Breus, Vladimir V; Thomas Basché; Carsten Sönnichsen; Wolfgang Tremel; Ingrid Hilger

    2015-01-01

    In the research field of nanoparticles, many studies demonstrated a high impact of the shape, size and surface charge, which is determined by the functionalization, of nanoparticles on cell viability and internalization into cells. This work focused on the comparison of three different nanoparticle types to give a better insight into general rules determining the biocompatibility of gold, Janus and semiconductor (quantum dot) nanoparticles. Endothelial cells were subject of this study, since ...

  6. Biocompatible Peritoneal Dialysis Fluids: Clinical Outcomes

    Directory of Open Access Journals (Sweden)

    Yeoungjee Cho

    2012-01-01

    Full Text Available Peritoneal dialysis (PD is a preferred home dialysis modality and has a number of added advantages including improved initial patient survival and cost effectiveness over haemodialysis. Despite these benefits, uptake of PD remains relatively low, especially in developed countries. Wider implementation of PD is compromised by higher technique failure from infections (e.g., PD peritonitis and ultrafiltration failure. These are inevitable consequences of peritoneal injury, which is thought to result primarily from continuous exposure to PD fluids that are characterised by their “unphysiologic” composition. In order to overcome these barriers, a number of more biocompatible PD fluids, with neutral pH, low glucose degradation product content, and bicarbonate buffer have been manufactured over the past two decades. Several preclinical studies have demonstrated their benefit in terms of improvement in host cell defence, peritoneal membrane integrity, and cytokine profile. This paper aims to review randomised controlled trials assessing the use of biocompatible PD fluids and their effect on clinical outcomes.

  7. Biocompatibility of polymethylmethacrylate resins used in dentistry.

    Science.gov (United States)

    Gautam, Rupali; Singh, Raghuwar D; Sharma, Vinod P; Siddhartha, Ramashanker; Chand, Pooran; Kumar, Rakesh

    2012-07-01

    Biocompatibility or tissue compatibility describes the ability of a material to perform with an appropriate host response when applied as intended. Poly-methylmethacrylate (PMMA) based resins are most widely used resins in dentistry, especially in fabrication of dentures and orthodontic appliances. They are considered cytotoxic on account of leaching of various potential toxic substances, most common being residual monomer. Various in vitro and in vivo experiments and cell based studies conducted on acrylic based resins or their leached components have shown them to have cytotoxic effects. They can cause mucosal irritation and tissue sensitization. These studies are not only important to evaluate the long term clinical effect of these materials, but also help in further development of alternate resins. This article reviews information from scientific full articles, reviews, or abstracts published in dental literature, associated with biocompatibility of PMMA resins and it is leached out components. Published materials were searched in dental literature using general and specialist databases, like the PubMED database. PMID:22454327

  8. Synthesis and energy transfer within carbon-based fluorescent rare earth nanoparticles and nanocomposites (Conference Presentation)

    Science.gov (United States)

    Yust, Brian G.; Chipara, Mircea; Saenz, Aaron

    2016-03-01

    Recently, there has been a great deal of interest in fluorescent and upconverting rare earth-based nanoparticles for biomedical imaging and photodynamic therapy applications. While many of the widely explored upconverting contrast agents are comprised of fluoride or oxide crystal structures, very little work has been done to investigate the up- and downconversion emission in rare earth-doped carbon nanocomposites. Of particular interest, graphene-UCNP nanocomposites and sesquicarbide nanoparticles may offer a wide range of new applications when coupled with the extraordinary optical properties of rare earth-doped systems, such as potential use as nano-transducers. Carbon-based nanocomposites and sesquicarbides doped with rare earth elements were synthesized using the microwave and solvothermal methods with additional brief high temperature heat treatments. They were then characterized by XRD, visible and NIR excitation and emission spectroscopy, as well as Raman spectrsocopy. Tuning of the emission manifold ratios was explored through different compositions and size. Also, energy transfer between the emitting ions and the electronic states of the host structure was explored. Finally, cytotoxicity was tested, and cellular uptake of these nanomaterials was performed with confocal microscopy.

  9. Feasibility of a lateral flow test for neurocysticercosis using novel up-converting nanomaterials and a lightweight strip analyzer.

    Directory of Open Access Journals (Sweden)

    Paul L A M Corstjens

    2014-07-01

    Full Text Available Neurocysticercosis is a frequent parasitic infection of the human brain, occurring in most of the world, and requires imaging of the brain to diagnose. To determine the burden of disease and to simplify diagnosis, a field-friendly rapid lateral flow (LF based antibody screening test was developed. The assay utilizes novel nano-sized up-converting phosphor (UCP reporter particles in combination with a portable lightweight analyzer and detects antibodies in serum samples reactive with bacterial-expressed recombinant (r T24H, a marker for detecting neurocysticercosis cases. Three sequential flow steps allow enrichment of antibodies on the Test (T line and consecutive binding of protein-A coated UCP reporter particles. Antibody binding was determined by measuring 550 nm emission after excitation of the UCP label with a 980 nm infrared (IR diode. Clinical sensitivity and specificity of the assay to detect cases of human neurocysticercosis with 2 or more viable brain cysts were 96% and 98%, respectively, using a sample set comprised of sera from 63 confirmed cases and 170 healthy parasite-naïve non-endemic controls.Proof-of-principle, of a rapid UCP-LF screening assay for neurocysticercosis was demonstrated. The assay utilized bacterial-expressed rT24H as a potential alternative for baculovirus-expressed rT24H. Performance of the UCP-LF assay was excellent, although further studies need to confirm that bacterial expressed antigen can entirely replace previously used baculovirus antigen. In addition, the increasing availability of commercial sources for UCP reporter materials as well as the accessibility of affordable semi-handheld scanners may allow UCP-based bioanalytical systems for point-of-care to evolve at an even faster pace.

  10. Rapid detection of abrin in foods with an up-converting phosphor technology-based lateral flow assay

    Science.gov (United States)

    Liu, Xiao; Zhao, Yong; Sun, Chongyun; Wang, Xiaochen; Wang, Xinrui; Zhang, Pingping; Qiu, Jingfu; Yang, Ruifu; Zhou, Lei

    2016-01-01

    Abrin is a natural plant toxin found in the seeds of Abrus precatorius. It may be used for food poisoning or bioterrorism, seriously endangering public health. In this study, a reliable method for the rapid detection of abrin in foods was developed, based on an up-converting phosphor technology-based lateral flow assay (abrin-UPT-LFA). Nine high-affinity monoclonal antibodies (mAbs) against abrin were prepared, and the optimum mAbs (mAb-6F4 and mAb-10E11) were selected for use in the assay in double-antibody-sandwich mode. The assay was confirmed to be specific for abrin, with a detection sensitivity of 0.1 ng mL−1 for standard abrin solutions. Good linearity was observed for abrin quantitation from 0.1 to 1000 ng mL−1 (r = 0.9983). During the analysis of various abrin-spiked food samples, the assay showed strong sample tolerance and a satisfactory limit of detection for abrin (0.5–10 ng g−1 for solid and powdered samples; 0.30–0.43 ng mL−1 for liquid samples). The analysis of suspected food samples, from sample treatment to result feed-back, could be completed by non-professionals within 20 min. Therefore, the abrin-UPT-LFA is a rapid, sensitive, and reliable method for the on-site detection of abrin in foods. PMID:27703269

  11. Upconverting core-shell nanocrystals with high quantum yield under low irradiance: On the role of isotropic and thick shells

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Stefan; Goldschmidt, Jan Christoph [Fraunhofer Institute for Solar Energy Systems, Heidenhofstraße 2, 79110 Freiburg (Germany); Johnson, Noah J. J.; Pichaandi, Jothirmayanantham; Veggel, Frank C. J. M. van [Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia V8W 3V6 (Canada)

    2015-11-21

    Colloidal upconverter nanocrystals (UCNCs) that convert near-infrared photons to higher energies are promising for applications ranging from life sciences to solar energy harvesting. However, practical applications of UCNCs are hindered by their low upconversion quantum yield (UCQY) and the high irradiances necessary to produce relevant upconversion luminescence. Achieving high UCQY under practically relevant irradiance remains a major challenge. The UCQY is severely limited due to non-radiative surface quenching processes. We present a rate equation model for migration of the excitation energy to show that surface quenching does not only affect the lanthanide ions directly at the surface but also many other lanthanide ions quite far away from the surface. The average migration path length is on the order of several nanometers and depends on the doping as well as the irradiance of the excitation. Using Er{sup 3+}-doped β-NaYF{sub 4} UCNCs, we show that very isotropic and thick (∼10 nm) β-NaLuF{sub 4} inert shells dramatically reduce the surface-related quenching processes, resulting in much brighter upconversion luminescence at simultaneously considerably lower irradiances. For these UCNCs embedded in poly(methyl methacrylate), we determined an internal UCQY of 2.0% ± 0.2% using an irradiance of only 0.43 ± 0.03 W/cm{sup 2} at 1523 nm. Normalized to the irradiance, this UCQY is 120× higher than the highest values of comparable nanomaterials in the literature. Our findings demonstrate the important role of isotropic and thick shells in achieving high UCQY at low irradiances from UCNCs. Additionally, we measured the additional short-circuit current due to upconversion in silicon solar cell devices as a proof of concept and to support our findings determined using optical measurements.

  12. Ferrite Nanoparticles in Pharmacological Modulation of Angiogenesis

    Science.gov (United States)

    Deshmukh, Aparna; Radha, S.; Khan, Y.; Tilak, Priya

    2011-07-01

    Nanoparticles are being explored in the targeted drug delivery of pharmacological agents : angiogenesis being one such novel application which involves formation of new blood vessels or branching of existing ones. The present study involves the use of ferrite nanoparticles for precise therapeutic modulation of angiogenesis. The ferrite nanoparticles synthesized by co-precipitation of ferrous and ferric salts by a suitable base, were found to be 10-20 nm from X-ray diffraction and TEM measurements. The magnetization measurements showed superparamagnetic behavior of the uncoated nanoparticles. These ferrite nanoparticles were found to be bio-compatible with lymphocytes and neural cell lines from the biochemical assays. The chick chorioallantoic membrane(CAM) from the shell of fertile white Leghorn eggs was chosen as a model to study angiogenic activity. An enhancement in the angiogenic activity in the CAM due to addition of uncoated ferrite nanoparticles was observed.

  13. Encapsulation of selenium in chitosan nanoparticles improves selenium availability and protects cells from selenium-induced DNA damage response

    Science.gov (United States)

    Selenium, an essential mineral, plays important roles in optimizing human health. Chitosan is an effective, naturally oriented material for synthesizing nanoparticles with polyanions and exhibit preferable properties such as biocompatibility, biodegradation and resistance to certain enzymes. We have...

  14. Biocompatible KMnF3 nanoparticular contrast agent with proper plasma retention time for in vivo magnetic resonance imaging.

    Science.gov (United States)

    Liu, Zhi-jun; Song, Xiao-xia; Xu, Xian-zhu; Tang, Qun

    2014-04-18

    Nanoparticular MRI contrast agents are rapidly becoming suitable for use in clinical diagnosis. An ideal nanoparticular contrast agent should be endowed with high relaxivity, biocompatibility, proper plasma retention time, and tissue-specific or tumor-targeting imaging. Herein we introduce PEGylated KMnF3 nanoparticles as a new type of T1 contrast agent. Studies showed that the nanoparticular contrast agent revealed high bio-stability with bovine serum albumin in PBS buffer solution, and presented excellent biocompatibility (low cytotoxicity, undetectable hemolysis and hemagglutination). Meanwhile the new contrast agent possessed proper plasma retention time (circulation half-life t1/2 is approximately 2 h) in the body of the administrated mice. It can be delivered into brain vessels and maintained there for hours, and is mostly cleared from the body within 48 h, as demonstrated by time-resolved MRI and Mn-biodistribution analysis. Those distinguishing features make it suitable to obtain contrast-enhanced brain magnetic resonance angiography. Moreover, through the process of passive targeting delivery, the T1 contrast agent clearly illuminates a brain tumor (glioma) with high contrast image and defined shape. This study demonstrates that PEGylated KMnF3 nanoparticles represent a promising biocompatible vascular contrast agent for magnetic resonance angiography and can potentially be further developed into an active targeted tumor MRI contrast agent.

  15. Preparation of biocompatible magnetite-carboxymethyl cellulose nanocomposite: Characterization of nanocomposite by FTIR, XRD, FESEM and TEM

    Science.gov (United States)

    Habibi, Neda

    2014-10-01

    The preparation and characterization of magnetite-carboxymethyl cellulose nano-composite (M-CMC) material is described. Magnetite nano-particles were synthesized by a modified co-precipitation method using ferrous chloride tetrahydrate and ferric chloride hexahydrate in ammonium hydroxide solution. The M-CMC nano-composite particles were synthesized by embedding the magnetite nanoparticles inside carboxymethyl cellulose (CMC) using a freshly prepared mixture of Fe3O4 with CMC precursor. Morphology, particle size, and structural properties of magnetite-carboxymethyl cellulose nano-composite was accomplished using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) and field emission scanning electron microscopy (FESEM) analysis. As a result, magnetite nano-particles with an average size of 35 nm were obtained. The biocompatible Fe3O4-carboxymethyl cellulose nano-composite particles obtained from the natural CMC polymers have a potential range of application in biomedical field.

  16. Jet blown PTFE for control of biocompatibility

    Science.gov (United States)

    Leibner, Evan Scott

    The development of fully hemocompatible cardiovascular biomaterials will have a major impact on the practice of modern medicine. Current artificial surfaces, unlike native vascular surfaces, are not able to control clot and thrombus formation. Protein interactions are an important component in hemocompatibility and can result in decreased patency due to thrombus formation or surface passivation which can improve endothelization. It is believed that controlling these properties, specifically the nanometer sizes of the fibers on the material's surface, will allow for better control of biological responses. The biocompatibility of Teflon, a widely used polymer for vascular grafts, would be improved with nanostructured control of surface features. Due to the difficultly in processing polytetrafluoroethylene (PTFE), it has not been possible to create nanofibrous PTFE surfaces. The novel technique of Jet Blowing allows for the formation of nanostructured PTFE (nPTFE). A systematic investigation into controlling polymer properties by varying the processing conditions of temperature, pressure, and gas used in the Jet Blowing allows for an increased understanding of the effects of plasticization on the material's properties. This fundamental understanding of the material science behind the Jet Blowing process has enabled control of the micro and nanoscale structure of nPTFE. While protein adsorption, a key component of biocompatibility, has been widely studied, it is not fully understood. Major problems in the field of biomaterials include a lack of standard protocols to measure biocompatibility, and inconstant literature on protein adsorption. A reproducible protocol for measuring protein adsorption onto superhydrophobic surfaces (ePTFE and nPTFE) has been developed. Both degassing of PBS buffer solutions and evacuation of the air around the expanded PTFE (ePTFE) prior to contact with protein solutions are essential. Protein adsorption experiments show a four

  17. Biostability and biocompatibility of modified polyurethane elastomers

    Science.gov (United States)

    Christenson, Elizabeth Marie

    Several strategies have been employed to increase the biostability of medical grade polyurethanes while maintaining the desirable properties of current poly(ether urethanes). It was hypothesized that polyurethane surface chemistry controls biodegradation/biostability that can lead to ultimate failure/success of these materials in clinical applications. Chemical modification or replacement of the susceptible soft segment was evaluated as a design strategy to increase the biostability of medical grade polyurethanes. The effect of soft segment chemistry on the phase morphology, mechanical properties and in vivo response of commercial polyurethanes were compared. Poly(ether urethane) (PEU), silicone-modified poly(ether urethane) (PEU-S), poly(carbonate urethane) (PCU) and silicone-modified poly(carbonate urethane) (PCU-S) elastomers were investigated. AFM phase imaging indicated that the overall two-phase morphology of poly(ether urethanes), necessary for its thermoplastic elastomeric properties, was not disrupted by changing the soft segment chemistry. All of the polyurethanes exhibited thermoplastic elastomeric behavior similar to that of the poly(ether urethane). Following material characterization, the biocompatibility of the polyurethane elastomers was evaluated using a subcutaneous cage implant protocol. All of the polyurethanes tested retained the excellent biocompatibility typical of poly(ether urethane) elastomers. Overall, the candidate polyurethanes were concluded to be suitable replacements of current poly(ether urethane) elastomers in medical applications. The results from the cage implant study and cell culture experiments indicated that monocytes adhere, differentiate and fuse to form foreign body giant cells (FBGCs) on all of the polyurethane specimens. It is now generally accepted that the reactive oxygen species released by these adherent macrophages and FBGCs initiate PEU biodegradation. ATR-FTIR analysis of explanted samples provided evidence of

  18. Effect of Surface Modification on Microbiol Polyhydroxyalkanoate Films on Biocompatibility

    Institute of Scientific and Technical Information of China (English)

    杨霰霜; 赵锴; 陈金春; 夏彩虹; 陈国强

    2001-01-01

    The purpose of this study was to investigate in vitro biocompatibility of a new type of polymer, polyhydroxybutyrate-co-hexanoate (PHBHHx). The hydrophilicity and biocompatibility were studied with two kinds of enzymes, amylase BAN480L and lipase Novozym388. The degree of hydrophilicity was observed using contact angle measurements. In vitro biocompatibility evaluations were carried out by direct incubation of mouse fibroblast cell line L929 on the polyhydroxyalkanoate (PHA) films. The samples treated with BAN480L showed that the PHA biocompatibility increased while the hydrophilicity decreased. Relative to untreated samples, the number of cells on the Novozym388 modified PHBHHx significant decrease as the hydrophilicity also decreased. The results indicated that other surface characteristics besides hydrophilicity influence the biocompatibility of PHBHHx films.

  19. Surface-treated biocompatible ZnS quantum dots: Synthesis, photo-physical and microstructural properties

    Science.gov (United States)

    Taherian, M.; Sabbagh Alvani, A. A.; Shokrgozar, M. A.; Salimi, R.; Moosakhani, S.; Sameie, H.; Tabatabaee, F.

    2014-03-01

    In the present study, the ZnS semiconductor quantum dots were successfully synthesized via an aqueous method utilizing glutathione (GSH), thioglycolic acid (TGA) and polyvinyl pyrrolidone (PVP) as capping agents. The structural, morphological and photo-physical properties and biocompatibility were investigated using comprehensive characterization techniques such as x-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), dynamic light scattering (DLS), Fourier transform infrared spectrometry (FT-IR), UV-Vis optical absorption, photoluminescence (PL) spectrometer and MTT assay. The XRD patterns showed a cubic zinc blende crystal structure and a crystallite size of about 2-3 nm using Scherrer's equation confirmed by the electron micrographs and Effective Mass Approximation (EMA). The DLS and zeta-potential results revealed that GSH capped ZnS nanoparticles have the narrowest size distribution with an average size of 27 nm and relatively good colloidal stability. Also, the FT-IR spectrum confirmed the interaction of the capping agent groups with ZnS nanoparticles. According to the UV-Vis absorption results, optical bandgap of the spherical capped nanoparticles is higher compared to the uncapped sample and could be wider than 3.67 eV (corresponding to the bulk ZnS), which is due to the quantum confinement effect. From photoluminescence spectra, it was found that the emission becomes more intensive and shifts towards the shorter wavelengths in the presence of the capping agent. Moreover, the emission mechanism of uncapped and capped ZnS was discussed in detail. Finally, the MTT results revealed the satisfactory (>94%) biocompatibility of GSH capped ZnS quantum dots which would be a promising candidate applicable in fluorescent biological labels.

  20. Preparation of monoclonal antibodies against ricin toxin and development of up-converting phosphor technology-based lateral flow assay for its quantitative detection%蓖麻毒素单抗制备及上转发光免疫层析定量检测方法研究

    Institute of Scientific and Technical Information of China (English)

    王晓晨; 周蕾; 孙崇云; 赵勇; 王鑫蕊; 张平平; 杨瑞馥; 马馨

    2016-01-01

    Objective To develop an up-converting phosphor technology based lateral flow assay ( UPT-LF) to detect ricin toxin ( RT) quickly, accurately and quantitatively.Methods Ricin-monoclonal antibodies were prepared and their affinity was evaluated before four types of monoclonal antibodies with the highest titer were applied to couple with the up-converting phosphor nano-particles ( UCP-NPs) as the bio-conjugate and disperse on the analysis membrane as the test line, respectively.Following systematic optimization to establish the RT-UPT-LF strip, the sensitivity, precision, quantita-tive ability and specificity of RT-UPT-LF were evaluated.Results The detection could be accomplished within 15 min and the detection limit of the RT-UPT-LF assay could reach 0.5 ng/ml within the quantitative detection range of 0.5-1000 ng/ml.Other non-specific toxins at a concentration of 1000 ng/ml did not cause any non-specific reactions.Conclusion The developed RT-UPT-LF strip provides a new means for on-site quantitative detection of ricin toxin.%目的:建立一种可快速、精确地对蓖麻毒素( RT)进行定量检测的上转发光免疫检测技术( UPT-LF),即RT-UPT-LF。方法采用杂交瘤细胞技术制备蓖麻毒素单克隆抗体并对效价进行评价;采用效价最高的4种单抗分别与上转发光纳米颗粒( UCP-NP)共价偶联,分别作为检测带,进而两两配伍,确定最优的配伍组合条件建立RT-UPT-LF方法;对RT-UPT-LF的敏感性、精密性、定量能力和特异性进行评价。结果与结论所建立的RT-UPT-LF方法可在15 min内完成对蓖麻毒素的检测,灵敏度可达0.5 ng/ml,定量范围为0.5~1000 ng/ml,与其他高浓度毒素无非特异反应,该法为蓖麻毒素检测提供了一种新手段。

  1. Evaluation of cytotoxicity of polypyrrole nanoparticles synthesized by oxidative polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Vaitkuviene, Aida [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Kaseta, Vytautas [Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Voronovic, Jaroslav [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Ramanauskaite, Giedre; Biziuleviciene, Gene [Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Ramanaviciene, Almira [NanoTechnas–Center of Nanotechnology and Material Science at Department of Analytical and Environmental Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, 03225 Vilnius (Lithuania); Ramanavicius, Arunas, E-mail: Arunas.Ramanavicius@chf.vu.lt [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Laboratory of BioNanoTechnology, Department of Materials Science and Electronics, Institute of Semiconductor Physics, State Scientific Research Institute Centre for Physical Sciences and Technology, A. Gostauto 11, LT-01108 Vilnius (Lithuania)

    2013-04-15

    Highlights: ► Polypyrrole nanoparticles synthesized by environmentally friendly polymerization at high concentrations are cytotoxic. ► Primary mouse embryonic fibroblast, mouse hepatoma and human T lymphocyte Jurkat cell lines were treated by Ppy nanoparticles. ► Polypyrrole nanoparticles at high concentrations inhibit cell proliferation. -- Abstract: Polypyrrole (Ppy) is known as biocompatible material, which is used in some diverse biomedical applications and seeming to be a very promising for advanced biotechnological applications. In order to increase our understanding about biocompatibility of Ppy, in this study pure Ppy nanoparticles (Ppy-NPs) of fixed size and morphology were prepared by one-step oxidative polymerization and their cyto-compatibility was evaluated. The impact of different concentration of Ppy nanoparticles on primary mouse embryonic fibroblasts (MEF), mouse hepatoma cell line (MH-22A), and human T lymphocyte Jurkat cell line was investigated. Cell morphology, viability/proliferation after the treatment by Ppy nanoparticles was evaluated. Obtained results showed that Ppy nanoparticles at low concentrations are biocompatible, while at high concentrations they became cytotoxic for Jurkat, MEF and MH-22A cells, and it was found that cytotoxic effect is dose-dependent.

  2. Ultrasmall lanthanide oxide nanoparticles for biomedical imaging and therapy

    CERN Document Server

    Lee, Gang Ho

    2014-01-01

    Most books discuss general and broad topics regarding molecular imagings. However, Ultrasmall Lanthanide Oxide Nanoparticles for Biomedical Imaging and Therapy, will mainly focus on lanthanide oxide nanoparticles for molecular imaging and therapeutics. Multi-modal imaging capabilities will discussed, along with up-converting FI by using lanthanide oxide nanoparticles. The synthesis will cover polyol synthesis of lanthanide oxide nanoparticles, Surface coatings with biocompatible and hydrophilic ligands will be discussed and TEM images and dynamic light scattering (DLS) patterns will be

  3. FABRICATION AND BIOCOMPATIBILITY OF CELL OUTER MEMBRANE MIMETIC SURFACES

    Institute of Scientific and Technical Information of China (English)

    Ming-ming Zong; Yong-kuan Gong

    2011-01-01

    The surface design used for improving biocompatibility is one of the most important issues for the fabrication of medical devices. For mimicking the ideal surface structure of cell outer membrane, a large number of polymers bearing phosphorylcholine (PC) groups have been employed to modify the surfaces of biomaterials and medical devices. It has been demonstrated that the biocompatibility of the modified materials whose surface is required to interact with a living organism has been obviously improved by introducing PC groups. In this review, the fabrication strategies of cell outer membrane mimetic surfaces and their resulted biocompatibilities were summarized.

  4. Overview of Stabilizing Ligands for Biocompatible Quantum Dot Nanocrystals

    Directory of Open Access Journals (Sweden)

    Aaron Clapp

    2011-11-01

    Full Text Available Luminescent colloidal quantum dots (QDs possess numerous advantages as fluorophores in biological applications. However, a principal challenge is how to retain the desirable optical properties of quantum dots in aqueous media while maintaining biocompatibility. Because QD photophysical properties are directly related to surface states, it is critical to control the surface chemistry that renders QDs biocompatible while maintaining electronic passivation. For more than a decade, investigators have used diverse strategies for altering the QD surface. This review summarizes the most successful approaches for preparing biocompatible QDs using various chemical ligands.

  5. Chain formation and aging process in biocompatible polydisperse ferrofluids: experimental investigation and Monte Carlo simulations.

    Science.gov (United States)

    Bakuzis, Andris Figueiroa; Branquinho, Luis César; e Castro, Leonardo Luiz; e Eloi, Marcos Tiago de Amaral; Miotto, Ronei

    2013-05-01

    We review the use of Monte Carlo simulations in the description of magnetic nanoparticles dispersed in a liquid carrier. Our main focus is the use of theory and simulation as tools for the description of the properties of ferrofluids. In particular, we report on the influence of polydispersity and short-range interaction on the self-organization of nanoparticles. Such contributions are shown to be extremely important for systems characterized by particles with diameters smaller than 10nm. A new 3D polydisperse Monte Carlo implementation for biocompatible magnetic colloids is proposed. As an example, theoretical and simulation results for an ionic-surfacted ferrofluid dispersed in a NaCl solution are directly compared to experimental data (transmission electron microscopy - TEM, magneto-transmissivity, and electron magnetic resonance - EMR). Our combined theoretical and experimental results suggest that during the aging process two possible mechanisms are likely to be observed: the nanoparticle's grafting decreases due to aggregate formation and the Hamaker constant increases due to oxidation. In addition, we also briefly discuss theoretical agglomerate formation models and compare them to experimental data. PMID:23360743

  6. Tribological study of lubricious DLC biocompatible coatings.

    Science.gov (United States)

    Brizuela, M; Garcia-Luis, A; Viviente, J L; Braceras, I; Oñate, J I

    2002-12-01

    DLC (diamond-like carbon) coatings have remarkable tribological properties due mainly to their good frictional behavior. These coatings can be applied in many industrial and biomedical applications, where sliding can generate wear and frictional forces on the components, such as orthopaedic metal implants. This work reports on the development and tribological characterization of functionally gradient titanium alloyed DLC coatings. A PVD-magnetron sputtering technique has been used as the deposition method. The aim of this work was to study the tribological performance of the DLC coating when metal to metal contact (cobalt chromium or titanium alloys) takes place under dry and lubricated test conditions. Prior work by the authors demonstrates that the DLC coating reduced considerably the wear of the ultra-high-molecular-weight polyethylene (UHMWPE). The DLC coating during mechanical testing exhibited a high elastic recovery (65%) compared to the values obtained from Co-Cr-Mo (15%) and Ti-6Al-4V (23%). The coating exhibited an excellent tribo-performance against the Ti-6Al-4V and Co-Cr-Mo alloys, especially under dry conditions presenting a friction value of 0.12 and almost negligible wear. This coating has passed biocompatibility tests for implant devices on tissue/bone contact according to international standards (ISO 10993). PMID:15348654

  7. Eicosanoid release as laboratory indicator of biocompatibility.

    Science.gov (United States)

    Mahiout, A; Jörres, A; Schultze, G; Meinhold, H; Kessel, M

    1989-06-01

    Biocompatibility evaluation of extracorporeal devices requires the establishment of sensitive indicators of blood cells/surface interactions. Among others, arachidonic acid derivatives, such as prostaglandins and thromboxanes, play an important role in the cell control systems. Hence, the release of eicosanoids during blood exposure to dialyzer membranes was investigated. Experiments included in vitro incubation of human blood with flat membranes (FM), as well as ex vivo perfusion of hollow fiber membranes (HFM) with blood from healthy volunteers in single-pass fashion. In both models, a significant release of prostaglandin E2 (PGE2) and thromboxane B2 (TXB2) was detected. In addition, the amount of eicosanoid release depended on the type of membrane tested. After a 10-min FM incubation with fresh blood, plasma concentrations of TXB2 and PGE2 were pronounced by polycarbonate when compared to Cuprophan and polyacrylonitrile. During 10 min of open loop perfusion of HFM, polymethylmethacrylate was the most active biomaterial, whereas the reactivity of Cuprophan was significantly lower. Among HFM, Hemophan was by far the less active. These results indicate that the release of eicosanoids represents a sensitive parameter of blood cells/membrane reactivity. Thus, the question arises as to whether or not the extracorporeal process of cyclooxygenase activity could contribute to the clinical side effects of chronical hemodialysis.

  8. Forsterite Nanopowder: Structural Characterization and Biocompatibility Evaluation

    Institute of Scientific and Technical Information of China (English)

    M.A.Naghiu; M.Gorea; E.Mutch; F.Kristaly; M.Tomoaia-Cotisel

    2013-01-01

    Forsterite,a new biocompatible material was synthesized from Mg(NO3)2·6H20 and TEOS by using the sol-gel method.The material was then heated at 800,900 and 1000 ℃.The forsterite was noticed as the main crystalline phase in the material fired at 900 and 1000 ℃,while periclase (MgO) was present in all the samples.The tests confirm that in the first two samples forsterite is present as crystallites <60 nm,while in the sample synthesized at 1000 ℃ it forms aggregates of micrometre-sized grains.In vitro test was performed by immersing the forsterite powder in the simulating body fluids (SBF) and hydroxyapatite formation on the surface was investigated.We could evidence the formation of hydroxyapatite on the forsterite surface after 7 days of immersion.The MTT test confirmed that forsterite powders dissolution promote osteoblast proliferation of the human-type osteoblasts with no significant cytotoxicity effects.

  9. Biocompatible 3D Matrix with Antimicrobial Properties

    Directory of Open Access Journals (Sweden)

    Alberto Ion

    2016-01-01

    Full Text Available The aim of this study was to develop, characterize and assess the biological activity of a new regenerative 3D matrix with antimicrobial properties, based on collagen (COLL, hydroxyapatite (HAp, β-cyclodextrin (β-CD and usnic acid (UA. The prepared 3D matrix was characterized by Scanning Electron Microscopy (SEM, Fourier Transform Infrared Microscopy (FT-IRM, Transmission Electron Microscopy (TEM, and X-ray Diffraction (XRD. In vitro qualitative and quantitative analyses performed on cultured diploid cells demonstrated that the 3D matrix is biocompatible, allowing the normal development and growth of MG-63 osteoblast-like cells and exhibited an antimicrobial effect, especially on the Staphylococcus aureus strain, explained by the particular higher inhibitory activity of usnic acid (UA against Gram positive bacterial strains. Our data strongly recommend the obtained 3D matrix to be used as a successful alternative for the fabrication of three dimensional (3D anti-infective regeneration matrix for bone tissue engineering.

  10. Material Biocompatibility for PCR Microfluidic Chips

    KAUST Repository

    Kodzius, Rimantas

    2010-04-23

    As part of the current miniaturization trend, biological reactions and processes are being adapted to microfluidics devices. PCR is the primary method employed in DNA amplification, its miniaturization is central to efforts to develop portable devices for diagnostics and testing purposes. A problem is the PCR-inhibitory effect due to interaction between PCR reagents and the surrounding environment, which effect is increased in high-surface-are-to-volume ration microfluidics. In this study, we evaluated the biocompatibility of various common materials employed in the fabrication of microfluidic chips, including silicon, several kinds of silicon oxide, glasses, plastics, wax, and adhesives. Two-temperature PCR was performed with these materials to determine their PCR-inhibitory effect. In most of the cases, addition of bovine serum albumin effectively improved the reaction yield. We also studied the individual PCR components from the standpoint of adsorption. Most of the materials did not inhibit the DNA, whereas they did show noticeable interaction with the DNA polymerase. Our test, instead of using microfluidic devices, can be easily conducted in common PCR tubes using a standard bench thermocycler. Our data supports an overview of the means by which the materials most bio-friendly to microfluidics can be selected.

  11. Size-engineered biocompatible polymeric nanophotosensitizer for locoregional photodynamic therapy of cancer.

    Science.gov (United States)

    Jeong, Keunsoo; Park, Solji; Lee, Yong-Deok; Kang, Chi Soo; Kim, Hyun Jun; Park, Hyeonjong; Kwon, Ick Chan; Kim, Jungahn; Park, Chong Rae; Kim, Sehoon

    2016-08-01

    Current approaches in use of water-insoluble photosensitizers for photodynamic therapy (PDT) of cancer often demand a nano-delivery system. Here, we report a photosensitizer-loaded biocompatible nano-delivery formulation (PPaN-20) whose size was engineered to ca. 20nm to offer improved cell/tissue penetration and efficient generation of cytotoxic singlet oxygen. PPaN-20 was fabricated through the physical assembly of all biocompatible constituents: pyropheophorbide-a (PPa, water-insoluble photosensitizer), polycaprolactone (PCL, hydrophobic/biodegradable polymer), and Pluronic F-68 (clinically approved polymeric surfactant). Repeated microemulsification/evaporation method resulted in a fine colloidal dispersion of PPaN-20 in water, where the particulate PCL matrix containing well-dispersed PPa molecules inside was stabilized by the Pluronic corona. Compared to a control sample of large-sized nanoparticles (PPaN-200) prepared by a conventional solvent displacement method, PPaN-20 revealed optimal singlet oxygen generation and efficient cellular uptake by virtue of the suitably engineered size and constitution, leading to high in vitro phototoxicity against cancer cells. Upon administration to tumor-bearing mice by peritumoral route, PPaN-20 showed efficient tumor accumulation by the enhanced cell/tissue penetration evidenced by in vivo near-infrared fluorescence imaging. The in vivo PDT treatment with peritumorally administrated PPaN-20 showed significantly enhanced suppression of tumor growth compared to the control group, demonstrating great potential as a biocompatible photosensitizing agent for locoregional PDT treatment of cancer. PMID:27107384

  12. Histopathology of biocompatible hydroxylapatite-polyethylene composite in ossiculoplasty

    NARCIS (Netherlands)

    Meijer, AGW; Segenhout, HM; Albers, FWJ; van de Want, HJL

    2002-01-01

    The biocompatibility of hydroxylapatite-polyethylene composite implants (HAPEX, Smith and Nephew) was investigated in this study. Eleven middle ear prostheses, removed during revision surgery, have been examined by light microscopy, transmission electron microscopy and scanning electron microscopy.

  13. Hydroxyapatite-magnetite-MWCNT nanocomposite as a biocompatible multifunctional drug delivery system for bone tissue engineering

    Science.gov (United States)

    Pistone, Alessandro; Iannazzo, Daniela; Panseri, Silvia; Montesi, Monica; Tampieri, Anna; Galvagno, Signorino

    2014-10-01

    New magnetic hydroxyapatite-based nanomaterials as bone-specific systems for controlled drug delivery have been synthesized. The synthesized hydroxyapatite, HA, decorated with magnetite nanoparticles by a deposition method (HA/Fe3O4) and the nanocomposite system obtained using magnetic multi-walled carbon nanotubes (HA/MWCNT/Fe3O4) as a filler for HA have been characterized by chemical and morphological analyses, and their biological behavior was investigated. The systems have also been doped with clodronate in order to combine the effect of bone biomineralization induced by hydroxyapatite-based composites with the decrease of osteoclast formation induced by the drug. An analysis of the preosteoclastic RAW264.7 cell proliferation by MTT assay confirmed the high biocompatibility of the three systems. TRAP staining of RAW 264.7 conditioned with sRAKL to induce osteoclastogenesis, cultured in the presence of the systems doped and undoped with clodronate, showed the inhibitory effect of clodronate after we counted the MNC TRAP+cells but only in the osteoclast formation; in particular, the system HA/Fe3O4-Clo exerted a high inhibitory effect compared to the drug alone. These results demonstrate that the synthesized nanocomposites are a biocompatible magnetic drug delivery system and can represent a useful multimodal platform for applications in bone tissue engineering.

  14. Preparation and Characterization of Biocompatible Polymer Particles as Potential Nanocarriers for Inhalation Therapy

    Directory of Open Access Journals (Sweden)

    Katarzyna Jabłczyńska

    2015-01-01

    Full Text Available Aim. Investigation of the possibility of manufacturing biocompatible polymer particles which have the required properties for pulmonary delivery via inhalation and simultaneously act as vehicles of nanotherapeutics. Methods. Nanostructures were obtained from biocompatible polysaccharides by successive oxidation and reactive coiling in the aqueous phase. The resultant nanosuspensions of PAD (polyaldehyde dextran and DACMC (dialdehyde carbomethylcellulose were used as precursors in spray drying production of powders at variable process conditions. The resultant dry microparticles were characterized by SEM observations, and their properties related to delivery by inhalation were determined by laser diffraction spectrometry following the dispersion in the commercial inhaler. Finally, the possibility of the reconstitution of nanosuspensions by powders rehydration was evaluated. Results. Synthesized nanoparticles had size of 120–170 nm. Microparticles after drying had size of 0.5–5 µm and different surface morphology. Aerosolized particles obtained from powder dispersion in the inhaler had the volumetric median diameter of ~2 and ~1 µm for PAD and DACMC, respectively. Hydration of powders led to restoring the nanosuspensions with the average particle size similar to the precursor. Conclusions. PAD and DACMC can be used to obtain nanostructures which, after processing, take a form suitable for effective delivery to the lungs via inhalation.

  15. Green and red upconverted emission of hydrothermal synthesized Y2O3: Er3+-Yb3+ nanophosphors using different solvent ratio conditions

    International Nuclear Information System (INIS)

    The solvent effect on the green and red upconversion luminescence of hydrothermal synthesized Y2O3: Er3+-Yb3+ nanophosphors is analyzed. To that purpose, five different ethanol/water solvent ratios 1:3, 1:4, 1:5, 1:6 and 1:10 with 1 mol% of Er3+ and 2 mol% of Yb3+, were considered. According to results, the intensity of the visible emission depends on the SR synthesis conditions; the highest intensity of green and red emission, from a 970 nm excitation, is presented by the sample obtained using a 1:5 solvent ratio. In order to explain the results, an analysis of decaying times was done, the influence of the solvent effect on the material structure was investigated by a diffuse reflectance characterization and the upconverted emission mechanism was derived from a power pumping study. Characterization data indicated that the solvent ratio influences the luminescence properties of nanostructured materials.

  16. Nanoparticle-mediated interplay of chitosan and melatonin for improved wound epithelialisation.

    Science.gov (United States)

    Blažević, Filip; Milekić, Tamara; Romić, Marieta Duvnjak; Juretić, Marina; Pepić, Ivan; Filipović-Grčić, Jelena; Lovrić, Jasmina; Hafner, Anita

    2016-08-01

    Herein, we propose an innovative approach to improving wound healing. Our strategy is to deliver melatonin locally at the wound site by means of lecithin/chitosan nanoparticles. We used four types of chitosan that differed in terms of molecular weight and/or deacetylation degree. Melatonin encapsulation efficiency, nanoparticle size, zeta potential, biocompatibility and in vitro drug release were studied as a function of the type of chitosan used in preparation. The nanoparticles were evaluated in terms of their potential to promote wound epithelialisation via an in vitro scratch assay using a human keratinocyte (HaCaT) monolayer. The model wounds were treated with nanoparticle suspensions at a chitosan concentration of 5μgml(-1), which was based on preceding cell biocompatibility studies. Nanoparticles prepared with different types of chitosan showed similar effect on the keratinocyte proliferation/migration. Nanoparticle-mediated interplay of chitosan and melatonin was shown to be crucial for improved wound epithelialisation. PMID:27112895

  17. Development of nanostars as a biocompatible tumor contrast agent: toward in vivo SERS imaging

    Science.gov (United States)

    D’Hollander, Antoine; Mathieu, Evelien; Jans, Hilde; Vande Velde, Greetje; Stakenborg, Tim; Van Dorpe, Pol; Himmelreich, Uwe; Lagae, Liesbet

    2016-01-01

    The need for sensitive imaging techniques to detect tumor cells is an important issue in cancer diagnosis and therapy. Surface-enhanced Raman scattering (SERS), realized by chemisorption of compounds suitable for Raman spectroscopy onto gold nanoparticles, is a new method for detecting a tumor. As a proof of concept, we studied the use of biocompatible gold nanostars as sensitive SERS contrast agents targeting an ovarian cancer cell line (SKOV3). Due to a high intracellular uptake of gold nanostars after 6 hours of exposure, they could be detected and located with SERS. Using these nanostars for passive targeting after systemic injection in a xenograft mouse model, a detectable signal was measured in the tumor and liver in vivo. These signals were confirmed by ex vivo SERS measurements and darkfield microscopy. In this study, we established SERS nanostars as a highly sensitive contrast agent for tumor detection, which opens the potential for their use as a theranostic agent against cancer. PMID:27536107

  18. Optimization of PAMAM-gold nanoparticle conjugation for gene therapy

    OpenAIRE

    Figueroa, Elizabeth R.; Lin, Adam Y.; Yan, Jiaxi; Luo, Laureen; Foster, Aaron E.; Drezek, Rebekah A.

    2013-01-01

    The development of efficient and biocompatible non-viral vectors for gene therapy remains a great challenge, and exploiting the properties of both nanoparticle carriers and cationic polymers is an attractive approach. In this work, we have developed gold nanoparticle (AuNP) polyamidoamine (PAMAM) conjugates for use as non-viral transfection agents. AuPAMAM conjugates were prepared by crosslinking PAMAM dendrimers to carboxylic-terminated AuNPs via EDC and sulfo-NHS chemistry. EDC and sulfo-NH...

  19. Fibrous scaffolds fabricated by emulsion electrospinning: from hosting capacity to in vivo biocompatibility

    Science.gov (United States)

    Spano, F.; Quarta, A.; Martelli, C.; Ottobrini, L.; Rossi, R. M.; Gigli, G.; Blasi, L.

    2016-04-01

    Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post-implantation.Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post

  20. Biocompatible Nanocomplexes for Molecular Targeted MRI Contrast Agent

    Science.gov (United States)

    Chen, Zhijin; Yu, Dexin; Wang, Shaojie; Zhang, Na; Ma, Chunhong; Lu, Zaijun

    2009-07-01

    Accurate diagnosis in early stage is vital for the treatment of Hepatocellular carcinoma. The aim of this study was to investigate the potential of poly lactic acid-polyethylene glycol/gadolinium-diethylenetriamine-pentaacetic acid (PLA-PEG/Gd-DTPA) nanocomplexes using as biocompatible molecular magnetic resonance imaging (MRI) contrast agent. The PLA-PEG/Gd-DTPA nanocomplexes were obtained using self-assembly nanotechnology by incubation of PLA-PEG nanoparticles and the commercial contrast agent, Gd-DTPA. The physicochemical properties of nanocomplexes were measured by atomic force microscopy and photon correlation spectroscopy. The T1-weighted MR images of the nanocomplexes were obtained in a 3.0 T clinical MR imager. The stability study was carried out in human plasma and the distribution in vivo was investigated in rats. The mean size of the PLA-PEG/Gd-DTPA nanocomplexes was 187.9 ± 2.30 nm, and the polydispersity index was 0.108, and the zeta potential was -12.36 ± 3.58 mV. The results of MRI test confirmed that the PLA-PEG/Gd-DTPA nanocomplexes possessed the ability of MRI, and the direct correlation between the MRI imaging intensities and the nano-complex concentrations was observed ( r = 0.987). The signal intensity was still stable within 2 h after incubation of the nanocomplexes in human plasma. The nanocomplexes gave much better image contrast effects and longer stagnation time than that of commercial contrast agent in rat liver. A dose of 0.04 mmol of gadolinium per kilogram of body weight was sufficient to increase the MRI imaging intensities in rat livers by five-fold compared with the commercial Gd-DTPA. PLA-PEG/Gd-DTPA nanocomplexes could be prepared easily with small particle sizes. The nanocomplexes had high plasma stability, better image contrast effect, and liver targeting property. These results indicated that the PLA-PEG/Gd-DTPA nanocomplexes might be potential as molecular targeted imaging contrast agent.

  1. Biocompatible Nanocomplexes for Molecular Targeted MRI Contrast Agent

    Directory of Open Access Journals (Sweden)

    Yu Dexin

    2009-01-01

    Full Text Available Abstract Accurate diagnosis in early stage is vital for the treatment of Hepatocellular carcinoma. The aim of this study was to investigate the potential of poly lactic acid–polyethylene glycol/gadolinium–diethylenetriamine-pentaacetic acid (PLA–PEG/Gd–DTPA nanocomplexes using as biocompatible molecular magnetic resonance imaging (MRI contrast agent. The PLA–PEG/Gd–DTPA nanocomplexes were obtained using self-assembly nanotechnology by incubation of PLA–PEG nanoparticles and the commercial contrast agent, Gd–DTPA. The physicochemical properties of nanocomplexes were measured by atomic force microscopy and photon correlation spectroscopy. The T1-weighted MR images of the nanocomplexes were obtained in a 3.0 T clinical MR imager. The stability study was carried out in human plasma and the distribution in vivo was investigated in rats. The mean size of the PLA–PEG/Gd–DTPA nanocomplexes was 187.9 ± 2.30 nm, and the polydispersity index was 0.108, and the zeta potential was −12.36 ± 3.58 mV. The results of MRI test confirmed that the PLA–PEG/Gd–DTPA nanocomplexes possessed the ability of MRI, and the direct correlation between the MRI imaging intensities and the nano-complex concentrations was observed (r = 0.987. The signal intensity was still stable within 2 h after incubation of the nanocomplexes in human plasma. The nanocomplexes gave much better image contrast effects and longer stagnation time than that of commercial contrast agent in rat liver. A dose of 0.04 mmol of gadolinium per kilogram of body weight was sufficient to increase the MRI imaging intensities in rat livers by five-fold compared with the commercial Gd–DTPA. PLA–PEG/Gd–DTPA nanocomplexes could be prepared easily with small particle sizes. The nanocomplexes had high plasma stability, better image contrast effect, and liver targeting property. These results indicated that the PLA–PEG/Gd–DTPA nanocomplexes might be potential as molecular

  2. Metal Oxide Nanoparticles for Contrast Enhancement in Magnetic Resonance Imaging : Synthesis, Functionalization and Characterization

    OpenAIRE

    Ahrén, Maria

    2013-01-01

    This thesis work focuses on the design and production of nanoparticle based contrast agents for signal enhancement in magnetic resonance imaging (MRI). Three different synthesis routes are explored, primarily to produce crystalline gadolinium oxide (Gd2O3) nanoparticles, and surface modification is done to obtain stable, dispersible, biocompatible probes inducing high proton relaxivities. In Paper I and II we utilized the polyol synthesis method and nanoparticle purification was performed wit...

  3. Spectroscopic studies on the interaction of cysteine capped CuS nanoparticles with tyrosine

    Energy Technology Data Exchange (ETDEWEB)

    Prasanth, S.; Raj, D. Rithesh; Kumar, T. V. Vineesh; Sudarsanakumar, C. [School of Pure and Applied Physics, Mahatma Gandhi University Kottayam, Kerala (India)

    2015-06-24

    Biocompatible cysteine coated CuS nanoparticles were synthesized by a simple aqueous solution method. Hexagonal phase of the samples were confirmed from X-ray diffraction and particle size found to be 9 nm. The possible interaction between the bioactive cysteine capped CuS nanoparticles and tyrosine were investigated using spectroscopic techniques such as UV-Visible absorption and fluorescence spectroscopy. It is observed that the luminescence intensity of tyrosine molecule enhanced by the addition CuS nanoparticles.

  4. PH-Responsive mechanised nanoparticles gated by semirotaxanes

    KAUST Repository

    Khashab, Niveen M.

    2009-01-01

    A [2]pseudorotaxane-based mechanised nanoparticle system, which operates within an aqueous acidic environment, has been prepared and characterised; this integrated system affords both water-soluble stalk and ring components in an effort to improve the biocompatibility of these promising new drug delivery vehicles. © The Royal Society of Chemistry 2009.

  5. Nano-lipoidal carriers of tretinoin with enhanced percutaneous absorption, photostability, biocompatibility and anti-psoriatic activity.

    Science.gov (United States)

    Raza, Kaisar; Singh, Bhupinder; Lohan, Shikha; Sharma, Gajanand; Negi, Poonam; Yachha, Yukhti; Katare, Om Prakash

    2013-11-01

    Tretinoin (TRE) is a widely used retinoid for the topical treatment of acne, psoriasis, skin cancer and photoaging. Despite unmatchable efficacy, it is associated with several vexatious side effects like marked skin erythema, peeling and irritation, eventually leading to poor patient compliance. Its photo-instability and high lipophilicity also pose challenges in the development of a suitable topical product. The present study, therefore, aims to develop biocompatible lipid-based nanocarriers of TRE to improve its skin delivery, photostability, biocompatibility and pharmacodynamic efficacy. The TRE-loaded liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanostructured lipidic carriers (NLCs) were prepared and characterized for micromeritics, surface charge, percent drug efficiency and morphology. Bioadhesive hydrogels of the developed systems were also evaluated for rheological characterization, photostability, ex vivo skin permeation and retention employing porcine skin, and anti-psoriatic activity in mouse tail model. Nanoparticulate carriers (SLNs, NLCs) offered enhanced photostability, skin transport and anti-psoriatic activity vis-à-vis the vesicular carriers (liposomes, ethosomes) and the marketed product. However, all the developed nanocarriers were found to be more biocompatible and effective than the marketed product. These encouraging findings can guide in proper selection of topical carriers among diversity of such available carriers systems. PMID:23973754

  6. Nano-lipoidal carriers of tretinoin with enhanced percutaneous absorption, photostability, biocompatibility and anti-psoriatic activity.

    Science.gov (United States)

    Raza, Kaisar; Singh, Bhupinder; Lohan, Shikha; Sharma, Gajanand; Negi, Poonam; Yachha, Yukhti; Katare, Om Prakash

    2013-11-01

    Tretinoin (TRE) is a widely used retinoid for the topical treatment of acne, psoriasis, skin cancer and photoaging. Despite unmatchable efficacy, it is associated with several vexatious side effects like marked skin erythema, peeling and irritation, eventually leading to poor patient compliance. Its photo-instability and high lipophilicity also pose challenges in the development of a suitable topical product. The present study, therefore, aims to develop biocompatible lipid-based nanocarriers of TRE to improve its skin delivery, photostability, biocompatibility and pharmacodynamic efficacy. The TRE-loaded liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanostructured lipidic carriers (NLCs) were prepared and characterized for micromeritics, surface charge, percent drug efficiency and morphology. Bioadhesive hydrogels of the developed systems were also evaluated for rheological characterization, photostability, ex vivo skin permeation and retention employing porcine skin, and anti-psoriatic activity in mouse tail model. Nanoparticulate carriers (SLNs, NLCs) offered enhanced photostability, skin transport and anti-psoriatic activity vis-à-vis the vesicular carriers (liposomes, ethosomes) and the marketed product. However, all the developed nanocarriers were found to be more biocompatible and effective than the marketed product. These encouraging findings can guide in proper selection of topical carriers among diversity of such available carriers systems.

  7. Physicochemical properties and biocompatibility of a polymer-paclitaxel conjugate for cancer treatment

    Directory of Open Access Journals (Sweden)

    Yang D

    2011-10-01

    Full Text Available Danbo Yang1, Sang Van2, Jian Liu2, Jing Wang1, Xinguo Jiang3, Yiting Wang1, Lei Yu1,2 1Biomedical Engineering and Technology Institute, Institutes for Advanced Interdisciplinary Research, East China Normal University, Shanghai, China; 2Biomedical Group, Nitto Denko Technical Corporation, Oceanside, CA; 3School of Pharmacy, Fudan University, Shanghai, ChinaBackground: Poly(L-γ-glutamylglutamine paclitaxel (PGG-PTX conjugate is a non-diblock polymeric drug nanoparticle intended to improve the therapeutic index of paclitaxel. The purpose of the present study was to elucidate further the physicochemical properties of PGG-PTX in order to proceed with its clinical development.Methods and results: PGG-PTX was designed by integration of a hydrophobic paclitaxel conjugate through an added hydrophilic glutamic acid onto poly(L-glutamic acid. The addition of a flexible glutamic linker between PGA and paclitaxel resulted in spontaneous self-assembly of a PGG-PTX conjugate into nanoparticles. The PGG-PTX conjugate was stable as a lyophilized solid form. An in vitro viability experiment showed that PGG-PTX was effective after a longer incubation period, the same trend as Taxol. In vitro studies using NCI-H460 and B16F0 cancer cells demonstrated significantly high cellular uptake after 30 minutes of incubation. The in vivo biocompatibility of PGG-PTX conjugate was evaluated in the NCI-H460 tumor model, the assessment of tissue seemed to be normal after 21 days of treatment.Conclusion: These results are encouraging for further development of non-block polymeric paclitaxel nanoparticles for treatment of cancer.Keywords: polymer conjugate, paclitaxel, poly(L-γ-glutamylglutamine, drug delivery, physicochemical properties, nanoparticles

  8. [Study on biocompatibility of titanium alloys].

    Science.gov (United States)

    Kodama, T

    1989-06-01

    The biocompatibility of two different titanium alloys, Ti-6Al-4V ELI and Ti-5Al-2, 5Fe, and pure titanium were evaluated. The results were as follows: 1) Titanium alloys were implanted into the dorsal subcutaneous tissues of the Hartley guinea-pig for 12 weeks, immersed in calf serum or in Ringer's solution for 8 weeks. The surface changes of the titanium alloys were observed by SEM and the chemical composition was analyzed by XMA. No evident surface changes were found. 2) Three hundred mg, 200 mg and 100 mg of the powders of the tested materials were immersed in 2ml of Eagle's MEM, incubated for 1-7 days, 8-21 days and 22-70 days at 37 C degrees. The amount of metallic elements dissolved in the solutions was measured by ICP and AAS. The detected corrosion rates of V and Al contained in the solution, in which Ti-6Al-4V ELI 100 mg was immersed for 1-7 days, were 194.3 +/- 17.6 and 73.0 +/- 28, 1 pg/mg alloy/day, respectively. V was released more than Al. The amount of Ti was below the detectable limit. The solution Ti-5Al-2.5 Fe 100 mg immersed for 1-7 days contained 31.9 +/- 34.4 pg/mg alloy/day Fe and 25.7 +/- 6.3 pg/mg alloy/day Al. Only in the solution 300 mg immersed for 1-7 days was Ti detected at 1.4 pg/mg alloy/day. 3) By the bacterial mutation assay of Salmonella typhimurium TA 98, Salmonella typhimurium TA 100 and Escherichia coli WP2 uvrA, the solutions, in which the tested materials were immersed, were not found to be mutagenic. 4) By the UDS assay, the grain counts on autoradiography with the solutions, in which the tested materials were immersed, were not greater than the negative control. The results suggest an excellent corrosion resistance of the titanium alloys. Mutagenicity was negative by these mutation assays, indicating that the tested alloys and pure titanium are safe for humans and animals.

  9. Local heating with titanium nitride nanoparticles

    DEFF Research Database (Denmark)

    Guler, Urcan; Ndukaife, Justus C.; Naik, Gururaj V.;

    2013-01-01

    We investigate the feasibility of titanium nitride (TiN) nanoparticles as local heat sources in the near infrared region, focusing on biological window. Experiments and simulations provide promising results for TiN, which is known to be bio-compatible.......We investigate the feasibility of titanium nitride (TiN) nanoparticles as local heat sources in the near infrared region, focusing on biological window. Experiments and simulations provide promising results for TiN, which is known to be bio-compatible....

  10. Facile preparation of boronic acid functionalized Fe-core/Au-shell magnetic nanoparticles for covalent immobilization of adenosine

    NARCIS (Netherlands)

    Pham, Tuan Anh; Kumar, Nanjundan Ashok; Jeong, Yeon Tae

    2010-01-01

    The synthesis of biocompatible magnetic nanoparticles is one of the important topics in nanoscience because such materials have potential biomedical applications. Herein, we report a facile approach for surface functionalization of magnetic nanoparticles (MNPs) with boronic acid and their use for th

  11. A New Method for the Synthesis of Selenium Nanoparticles and the Application to Construction of H2O2 Biosensor

    Institute of Scientific and Technical Information of China (English)

    Juan ZHANG; Sheng Yi ZHANG; Jing Juan XU; Hong Yuan CHEN

    2004-01-01

    The well-distributed, stable selenium nanoparticles (10 nm) with good adhesive ability and biocompatibility were successfully synthesized by using the template of chitosan cross-linked with glutaradehyde. The resulting selenium nanoparticles were used as a new carrier for horseradish peroxidase to construct H2O2 biosensors with good performances.

  12. An estimate of the prevalence of biocompatible and habitable planets.

    Science.gov (United States)

    Fogg, M J

    1992-01-01

    A Monte Carlo computer model of extra-solar planetary formation and evolution, which includes the planetary geochemical carbon cycle, is presented. The results of a run of one million galactic disc stars are shown where the aim was to assess the possible abundance of both biocompatible and habitable planets. (Biocompatible planets are defined as worlds where the long-term presence of surface liquid water provides environmental conditions suitable for the origin and evolution of life. Habitable planets are those worlds with more specifically Earthlike conditions). The model gives an estimate of 1 biocompatible planet per 39 stars, with the subset of habitable planets being much rarer at 1 such planet per 413 stars. The nearest biocompatible planet may thus lie approximately 14 LY distant and the nearest habitable planet approximately 31 LY away. If planets form in multiple star systems then the above planet/star ratios may be more than doubled. By applying the results to stars in the solar neighbourhood, it is possible to identify 28 stars at distances of < 22 LY with a non-zero probability of possessing a biocompatible planet.

  13. The immunomodulatory effects of titanium dioxide and silver nanoparticles.

    Science.gov (United States)

    Lappas, Courtney M

    2015-11-01

    Due to their characteristic physical, chemical and optical properties, titanium dioxide and silver nanoparticles are attractive tools for use in a wide range of applications. The use of nanoparticles for biological applications is, however, dependent upon their biocompatibility with living cells. Because of the importance of inflammation as a modulator of human health, the safe and efficacious in vivo use of titanium dioxide and silver nanoparticles is inherently linked to a favorable interaction with immune system cells. However, both titanium dioxide and silver nanoparticles have demonstrated potential to exert immunomodulatory and immunotoxic effects. Titanium dioxide and silver nanoparticles are readily internalized by immune system cells, may accumulate in peripheral lymphoid organs, and can influence multiple manifestations of immune cell activity. Although the factors influencing the biocompatibility of titanium dioxide and silver nanoparticles with immune system cells have not been fully elucidated, nanoparticle core composition, size, concentration and the duration of cell exposure seem to be important. Because titanium dioxide and silver nanoparticles are widely utilized in pharmaceutical, commercial and industrial products, it is vital that their effects on human health and immune system function be more thoroughly evaluated.

  14. In vitro and in vivo CT imaging using bismuth sulfide modified with a highly biocompatible Pluronic F127

    Science.gov (United States)

    Chen, Jun; Yang, Xiao-Quan; Meng, Yuan-Zheng; Huang, Huan-Huan; Qin, Meng-Yao; Yan, Dong-Mei; Zhao, Yuan-Di; Ma, Zhi-Ya

    2014-07-01

    Probe bismuth sulfide modified with Pluronic F127 (Bi2S3-PF127), which has high biocompatibility and dispersibility, is synthesized using triblock copolymer Pluronic F127 to modify hydrophobic Bi2S3 nanoparticles that are prepared by a hot injection method. TEM results show that most of the probe has a length of about 14.85 ± 1.70 nm and a breadth of about 4.79 ± 0.63 nm. After injected into the tail vein of a mouse, the probe has obvious CT contrast enhancement capability from x-ray CT imaging results. Meanwhile, the probe’s in vivo toxicity is also studied. It is found that hematoxylin and eosin stains of major organs have no change. A biochemical analysis (alanine aminotransferase and aspartate aminotransferase) prove the probe has no adverse effects. The results of a blood analysis (white blood cell count, red blood cell count, hemoglobin, and platelet count) are also normal. The biological distribution of Bi by ICP-AES shows that most of nanoparticles are cleaned out after injection 48 h, and the circulation half-life of the probe is 5.0 h, suggesting that Bi2S3-PF127 has a long circulation and indicating that the Bi2S3-PF127 probe has good biocompatibility and safety.

  15. Nano-CeO2 decorated graphene based chitosan nanocomposites as enzymatic biosensing platform: fabrication and cellular biocompatibility assessment.

    Science.gov (United States)

    De, Sriparna; Mohanty, Smita; Nayak, Sanjay Kumar

    2015-09-01

    The present study summarizes the designing of a green transducer phase based on nano-cerium oxide (CeO2) decorated reduced graphene oxide (RGO) reinforced chitosan nanocomposites as an effective enzyme immobilizer and bio-sensing matrix for glucose analyte. Also, it scrutinizes the biocompatibility and cell viability of the synthesized nanohybrid with human fibroblastic macrophage cell line. CeO2 nanoparticles (NPs) were successfully grown on graphene nanosheet in the presence of cationic surfactant followed by facile hydrothermal treatment. The eventual growth of synthesized CeO2 nanocrystals on the graphene layer was confirmed from X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman analysis. The biocompatibility of the synthesized nanohybrid was also evident from the MTT assay. Glucose oxidase (GOx) was employed on the green polymer nanocomposites modified FTO electrode to fabricate an enzymatic bioelectrode. The electroanalytical response of the GOx/nano-CeO2/RGO/CS/FTO bioelectrode towards electrooxidation of glucose analyte was investigated by electrochemical impedance (EIS) and cyclic voltammetry (CV) study. The resulting biosensor exhibited a good electrochemical response to glucose within the linear detection range of 0.05-6.5 mM with a low detection limit of 2 μM and a sensitivity of 7.198 μA mM(-1) cm(-2). The bioelectrode also showed good shelf life (~10 weeks) and negligible interfering ability under controlled environment. The obtained results indicate that nano-CeO2/RGO nanohybrid based chitosan nanocomposites achieve a biocompatible biosensing platform for effective enzyme immobilization due to the excellent synergistic effects between the CeO2 nanoparticles and graphene sheet.

  16. Solubility of dense CO2 in two biocompatible acrylate copolymers

    Directory of Open Access Journals (Sweden)

    A. R. C. Duarte

    2006-06-01

    Full Text Available Biocompatible polymers and copolymers are frequently being used as part of controlled delivery systems. These systems can be prepared using a "clean and environment friendly" technology like supercritical fluids. One great advantage of this process is that compressed carbon dioxide has excellent plasticizing properties and can swell most biocompatible polymeric matrixes, thus promoting drug impregnation processes. Mass sorption of two acrylate biocompatible copolymers contact with supercritical carbon dioxide is reported. Equilibrium solubility of dense carbon dioxide in poly(methylmethacrylate-co-ethylhexylacrylate and poly(methylmethacrylate-co-ethylhexylacrylate-co-ethyleneglycoldimethacrylate was studied by a static method at 10.0 MPa and 313 K. The reticulated copolymer had Fickean behavior and its diffusion coefficient was calculated, under operating conditions.

  17. BIOCOMPATIBILITY EVALUATION OF XANTHAN/CHONDROITIN SULFATE HYDROGELS

    Directory of Open Access Journals (Sweden)

    Ana-Maria Oprea

    2012-03-01

    Full Text Available The in vitro and in vivo biocompatibility of xanthan/chondroitin sulfate hydrogels (X/CS in differentmixing ratios was investigated. The in vitro biocompatibility evaluation was performed by a chemiluminescent assayusing microorganisms such as Saccharomyces pombe. The cellular growth of S. pombe in presence of thexanthan/chondroitin sulfate hydrogels containing up to 20 % chondroitin sulfate was examinated comparatively withxanthan hydrogel.The in vivo evaluation was performed by toxicity test and subcutaneously implantation in rats. It has been establisheda lethal dose (LD50 bigger than 3200 mg/kg for all studied hydrogels, therefore they are nontoxic materials.The in vivo 30 days testing performed by subcutaneous implantation showed that the X/CS matrices were easilyabsorbed without side-effects, demonstrating their biocompatibility and effectiveness as potential drug delivery systems.

  18. Green fabrication of agar-conjugated Fe{sub 3}O{sub 4} magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, S; Huang, B Y; Lin, P Y; Chang, C W [Department of Chemistry and Center for Nanoscience and Nanotechnology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China); Hsieh, S L [Department of Seafood Science, National Kaohsiung Marine University, Kaohsiung 81157, Taiwan (China); Wu, C C [Department of Nutrition and Health Sciences, Chang Jung Christian University, Tainan 71101, Taiwan (China); Wu, C H [Department of Computer Science and Information Engineering, National University of Kaohsiung, Kaohsiung 80811, Taiwan (China); Huang, Y S, E-mail: shsieh@facmail.NSYSU.edu.tw [Department of Food Science and Technology, Tajen University, Pingtung 90741, Taiwan (China)

    2010-11-05

    Magnetic nanoparticles are of great interest both for fundamental research and emerging applications. In the biomedical field, magnetite (Fe{sub 3}O{sub 4}) has shown promise as a hyperthermia-based tumor therapeutic. However, preparing suitable solubilized magnetite nanoparticles is challenging, primarily due to aggregation and poor biocompatibility. Thus methods for coating Fe{sub 3}O{sub 4} NPs with biocompatible stabilizers are required. We report a new method for preparing Fe{sub 3}O{sub 4} nanoparticles by co-precipitation within the pores of agar gel samples. Permeated agar gels were then dried and ground into a powder, yielding agar-conjugated Fe{sub 3}O{sub 4} nanoparticles. Samples were characterized using XRD, FTIR, TGA, TEM and SQUID. This method for preparing agar-coated Fe{sub 3}O{sub 4} nanoparticles is environmentally friendly, inexpensive and scalable.

  19. Cysteine modified polyaniline films improve biocompatibility for two cell lines

    International Nuclear Information System (INIS)

    This work focuses on one of the most exciting application areas of conjugated conducting polymers, which is cell culture and tissue engineering. To improve the biocompatibility of conducting polymers we present an easy method that involves the modification of the polymer backbone using L-cysteine. In this publication, we show the synthesis of polyaniline (PANI) films supported onto Polyethylene terephthalate (PET) films, and modified using cysteine (PANI-Cys) in order to generate a biocompatible substrate for cell culture. The PANI-Cys films are characterized by Fourier Transform infrared and UV–visible spectroscopy. The changes in the hydrophilicity of the polymer films after and before the modification were tested using contact angle measurements. After modification the contact angle changes from 86° ± 1 to 90° ± 1, suggesting a more hydrophylic surface. The adhesion properties of LM2 and HaCaT cell lines on the surface of PANI-Cys films in comparison with tissue culture plastic (TCP) are studied. The PANI-Cys film shows better biocompatibility than PANI film for both cell lines. The cell morphologies on the TCP and PANI-Cys film were examined by florescence and Atomic Force Microscopy (AFM). Microscopic observations show normal cellular behavior when PANI-Cys is used as a substrate of both cell lines (HaCaT and LM2) as when they are cultured on TCP. The ability of these PANI-Cys films to support cell attachment and growth indicates their potential use as biocompatible surfaces and in tissue engineering. - Highlights: • A new surface PANI-Cys was produced on films of polyethylene terephthalate. • The relationship between surface characteristics and biocompatibility is analyzed. • The PANI-Cys film presents good biocompatibility for two cell lines

  20. Cysteine modified polyaniline films improve biocompatibility for two cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Yslas, Edith I., E-mail: eyslas@exa.unrc.edu.ar [Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Agencia Postal Nro3, X580BYA Río Cuarto (Argentina); Cavallo, Pablo; Acevedo, Diego F.; Barbero, César A. [Departamento de Química, Universidad Nacional de Río Cuarto, Agencia Postal Nro3, X580BYA Río Cuarto (Argentina); Rivarola, Viviana A. [Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Agencia Postal Nro3, X580BYA Río Cuarto (Argentina)

    2015-06-01

    This work focuses on one of the most exciting application areas of conjugated conducting polymers, which is cell culture and tissue engineering. To improve the biocompatibility of conducting polymers we present an easy method that involves the modification of the polymer backbone using L-cysteine. In this publication, we show the synthesis of polyaniline (PANI) films supported onto Polyethylene terephthalate (PET) films, and modified using cysteine (PANI-Cys) in order to generate a biocompatible substrate for cell culture. The PANI-Cys films are characterized by Fourier Transform infrared and UV–visible spectroscopy. The changes in the hydrophilicity of the polymer films after and before the modification were tested using contact angle measurements. After modification the contact angle changes from 86° ± 1 to 90° ± 1, suggesting a more hydrophylic surface. The adhesion properties of LM2 and HaCaT cell lines on the surface of PANI-Cys films in comparison with tissue culture plastic (TCP) are studied. The PANI-Cys film shows better biocompatibility than PANI film for both cell lines. The cell morphologies on the TCP and PANI-Cys film were examined by florescence and Atomic Force Microscopy (AFM). Microscopic observations show normal cellular behavior when PANI-Cys is used as a substrate of both cell lines (HaCaT and LM2) as when they are cultured on TCP. The ability of these PANI-Cys films to support cell attachment and growth indicates their potential use as biocompatible surfaces and in tissue engineering. - Highlights: • A new surface PANI-Cys was produced on films of polyethylene terephthalate. • The relationship between surface characteristics and biocompatibility is analyzed. • The PANI-Cys film presents good biocompatibility for two cell lines.

  1. The quantification of biocompatibility: toward a new definition

    Science.gov (United States)

    Ratner, Buddy

    2008-03-01

    Implantable medical devices, and the biomaterials that comprise them, form a 100B business worldwide. Medical devices save lives and/or improve the quality of life for millions. Tissue engineering also makes extensive use of biomaterials -- biomaterials are an enabling technology for tissue engineering. A central word to understanding the effectiveness of such materials and devices is biocompatibility. The word ``biocompatible'' is widely used in reference to biomaterials and medical devices and most everyone has some value understanding of its meaning. Many formal definitions have been proposed for this word, but it is still largely used in an imprecise manner. Four descriptions or definitions of biocompatibility will be reviewed: a widely adopted definition from a consensus conference, a surgeon's perspective on this word, the regulatory agency view and the factors that clearly influence biocompatibility. In this talk, the classical definition of biocompatibility will be contrasted to a newer definition embracing molecular concepts and the understanding of normal wound healing. The biological data on the in vivo healing responses of mammals to implants will be described. A strategy to improve the healing of biomaterials will be presented. It is based upon surface molecular engineering. First, non-specific protein adsorption must be inhibited. Strategies to achieve this design parameter will be presented. Then methods to deliver the specific protein signals will be addressed. Matricellular proteins such as osteopontin, thrombospondin 2 and SPARC will be introduced with an emphasis on exploiting the special reactivity of such proteins. A discussion of the influence of surface textures and porosities will also be presented. Finally a new scheme based upon macrophage phenotypic pathways will be proposed that may allow a quantitative measure of extent of biocompatibility.

  2. NIR photoregulated chemo- and photodynamic cancer therapy based on conjugated polyelectrolyte-drug conjugate encapsulated upconversion nanoparticles

    Science.gov (United States)

    Yuan, Youyong; Min, Yuanzeng; Hu, Qinglian; Xing, Bengang; Liu, Bin

    2014-09-01

    The design of nanoplatforms with target recognition and near-infrared (NIR) laser photoregulated chemo- and photodynamic therapy is highly desirable but remains challenging. In this work, we have developed such a system by taking advantage of a conjugated polyelectrolyte (CPE)-drug conjugate and upconversion nanoparticles (UCNPs). The poly(ethylene glycol) (PEG) grafted CPE not only serves as a polymer matrix for UCNP encapsulation, but also as a fluorescent imaging agent, a photosensitizer as well as a carrier for chemotherapeutic drug doxorubicin (DOX) through a UV-cleavable ortho-nitrobenzyl (NB) linker. Upon 980 nm laser irradiation, the UCNPs emit UV and visible light. The up-converted UV light is utilized for controlled drug release through the photocleavage of the ortho-nitrobenzyl linker, while the up-converted visible light is used to initiate the polymer photosensitizer to produce reactive oxygen species (ROS) for photodynamic therapy. The NIR photo-regulated UCNP@CPE-DOX showed high efficiency of ROS generation and controlled drug release in cancer cells upon single laser irradiation. In addition, the combination therapy showed enhanced inhibition of U87-MG cell growth as compared to sole treatments. As two light sources with different wavelengths are always needed for traditional photodynamic therapy and photoregulated drug release, the adoption of UCNPs as an NIR light switch is highly beneficial to combined chemo- and photodynamic therapy with enhanced therapeutic effects.

  3. Synthesis of biocompatible polymers by plasma

    International Nuclear Information System (INIS)

    In this work biocompatible polymers were synthesized by plasma based on pyrrole, ethyleneglycol and allylamine. These monomers are biologically important because they contain oxygen and nitrogen in their structure and they form bonding like; N-H, C-N, C-O and O-H that are also in the human system. The polymers were synthesized with splendor electric discharges to 13.5 MHz, among 10 and 100 W, resistive coupling, pressure of 10-1 mbar and 180 minutes of reaction. The interaction of the biological systems with biomaterials depends in many cases of the properties that present the surfaces, because the rough and/or porous surfaces favor the adherence of cells. The results indicate that the ruggedness of the polymers can be controlled with the synthesis energy, since when modifying it flat and/or rough surfaces they are obtained. The compatibility of water with other solutions that it is a form of increasing the adhesion of cells with biopolymers. The affinity with water and solutions is evaluated calculating the contact angle of the polymers surface with drops of concentration solutions and similar composition to the extracellular liquid of the spinal marrow of the human body. The solutions that were proven were based on NaCl, NaCl-MgSO4, and a mixture Krebs-Ringer that has chemical composition and similar concentration to that of the fluids of the spinal marrow. In the Poly pyrrole (PPy)/Polyethyleneglycol (PEG) copolymer, the biggest angles corresponded to the Krebs-Ringer solution, in the interval of 18 to 14 degrees and those lowest to the NaCl solution, of 14.5 at 11 degrees. The Poly allylamine had the more high values with water in the interval of 16.5 to 12.5 degrees and those lowest with the NaCl solution, of 13 at 9.5 degrees. On the other hand, in the derived polymers of pyrrole the more high values corresponded to the treatment with water, until 37, and those lowest to the NaCl-MgSO4 solution, up to 10. The solutions where participated NaCl its produced the

  4. Functional biocompatible magnetite-cellulose nanocomposite fibrous networks: Characterization by fourier transformed infrared spectroscopy, X-ray powder diffraction and field emission scanning electron microscopy analysis

    Science.gov (United States)

    Habibi, Neda

    2015-02-01

    The preparation and characterization of functional biocompatible magnetite-cellulose nano-composite fibrous material is described. Magnetite-cellulose nano-composite was prepared by a combination of the solution-based formation of magnetic nano-particles and subsequent coating with amino celluloses. Characterization was accomplished using X-ray powder diffraction (XRD), fourier transformed infrared (FTIR) and field emission scanning electron microscopy (FESEM) analysis. The peaks of Fe3O4 in the XRD pattern of nanocomposite confirm existence of the nanoparticles in the amino cellulose matrix. Magnetite-cellulose particles exhibit an average diameter of roughly 33 nm as demonstrated by field emission scanning electron microscopy. Magnetite nanoparticles were irregular spheres dispersed in the cellulose matrix. The vibration corresponding to the Nsbnd CH3 functional group about 2850 cm-1 is assigned in the FTIR spectra. Functionalized magnetite-cellulose nano-composite polymers have a potential range of application as targeted drug delivery system in biomedical field.

  5. Size-Dependent Accumulation of PEGylated Silane-Coated Magnetic Iron Oxide Nanoparticles in Murine Tumors

    DEFF Research Database (Denmark)

    Larsen, Esben Kjær Unmack; Nielsen, T.; Wittenborn, T.;

    2009-01-01

    Magnetic nanoparticles (MNP) can be used as contrast-enhancing agents to visualize tumors by magnetic resonance imaging (MRI). Here we describe an easy synthesis method of magnetic nanoparticles coated with polyethylene glycol (PEG) and demonstrate size-dependent accumulation in murine tumors...... following intravenous injection. Biocompatible iron oxide MNPs coated with PEG were prepared by replacing oleic acid with a biocompatible and commercially available silane-PEG to provide an easy and effective method for chemical coating. The colloidal stable PEGylated MNPs were magnetically separated...

  6. Synthesis and characterization of biocompatible hydroxyapatite coated ferrite

    Indian Academy of Sciences (India)

    S Deb; J Giri; S Dasgupta; D Datta; D Bahadur

    2003-12-01

    Ferrite particles coated with biocompatible phases can be used for hyperthermia treatment of cancer. We have synthesized substituted calcium hexaferrite, which is not stable on its own but is stabilized with small substitution of La. Hexaferrite of chemical composition (CaO)0.75(La2O3)0.20(Fe2O3)6 was prepared using citrate gel method. Hydroxyapatite was prepared by precipitating it from aqueous solution of Ca(NO3)2 and (NH4)2HPO4 maintaining pH above 11. Four different methods were used for coating of hydroxyapatite on ferrite particles. SEM with EDX and X-ray diffraction analysis shows clear evidence of coating of hydroxy-apatite on ferrite particles. These coated ferrite particles exhibited coercive field up to 2 kOe, which could be made useful for hysteresis heating in hyperthermia. Studies by culturing BHK-21 cells and WBC over the samples show evidence of biocompatibility. SEM micrographs and cell counts give clear indication of cell growth on the surface of the sample. Finally coated ferrite particle was implanted in Kasaulli mouse to test its biocompatibility. The magnetic properties and biocompatibility studies show that these hydroxyapatite coated ferrites could be useful for hyperthermia.

  7. In vivo biocompatibility of nanostructured Chitosan/Peo membranes

    Directory of Open Access Journals (Sweden)

    V.A.S. Vulcani

    2015-08-01

    Full Text Available Electrospinning is a technique that allows the preparation of nanofibers from various materials. Chitosan is a natural and abundant easily obtained polymer, which, in addition to those features, proved to be biocompatible. This work used nanostructured chitosan and polyoxyethylene membranes as subcutaneous implants in Wistar rats to evaluate the biocompatibility of the material. Samples of the material and tissues adjacent to the implant were collected 7, 15, 30, 45 and 60 days post-implantation. Macroscopic integration of the material to the tissues was observed in the samples and slides for histopathological examination that were prepared. It was noticed that the material does not stimulate the formation of adherences to the surrounding tissues and that there is initial predominance of neutrophilia and lymphocytosis, with a declining trend according to the increase of time, featuring a non-persistent acute inflammatory process. However, the material showed fast degradation, impairing the macroscopic observation after fifteen days of implantation. It was concluded that the material is biocompatible and that new studies should be conducted, modifying the time of degradation by changes in obtaining methods and verifying the biocompatibility in specific tissues for biomedical applications.

  8. Biocompatibility of phosphorylcholine coated stents in normal porcine coronary arteries

    NARCIS (Netherlands)

    D.M. Whelan (Deirdre); S.C. Krabbendam; P.D. Verdouw (Pieter); P.W.J.C. Serruys (Patrick); E.A. van Vliet (Erwin); W.J. van der Giessen (Wim); H.M.M. van Beusekom (Heleen)

    2000-01-01

    textabstractOBJECTIVE: To improve the biocompatibility of stents using a phosphorylcholine coated stent as a form of biomimicry. INTERVENTIONS: Implantation of phosphorylcholine coated (n = 20) and non-coated (n = 21) stents was performed in the coronary arteries of 25 pigs. The an

  9. Biocompatibility studies of polyacrylonitrile membranes modified with carboxylated polyetherimide

    Energy Technology Data Exchange (ETDEWEB)

    Senthilkumar, S.; Rajesh, S.; Jayalakshmi, A.; Mohan, D., E-mail: mohantarun@gmail.com

    2013-10-15

    Poly (ether-imide) (PEI) was carboxylated and used as the hydrophilic modification agent for the preparation of polyacrylonitrile (PAN) membranes. Membranes were prepared with different blend compositions of PAN and CPEI by diffusion induced precipitation. The modified membranes were characterized by thermo gravimetric analysis (TGA), mechanical analysis, scanning electron microscopy (SEM) and contact angle measurement to understand the influence of CPEI on the properties of the membranes. The biocompatibility studies exhibited reduced plasma protein adsorption, platelet adhesion and thrombus formation on the modified membrane surface. The complete blood count (CBC) results of CPEI incorporated membranes showed stable CBC values and significant decrease in the complement activation were also observed. In addition to good cytocompatibility, monocytes cultured on these modified membranes exhibited improved functional profiles in 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. Thus it could be concluded that PAN/CPEI membranes with excellent biocompatibility can be useful for hemodialysis. Highlights: • Carboxylated PEI was prepared and utilized as hydrophilic modification agent. • CPEI incorporated into PAN to improved biocompatibility and cyto compatibility • Biocompatibility of membranes was correlated with morphology and hydrophilicity. • Antifouling studies of the PAN/CPEI membranes was studied by BSA as model foulant.

  10. [Biocompatibility of dental materials: Part 2. Materials with mucosal contact].

    Science.gov (United States)

    Klötzer, W T; Reuling, N

    1990-08-01

    Dental materials which are supposed to contact the oral, mucous membranes during their intended dental use may affect our patients health in different ways. Their local and systemic toxicity, and their allergenic and tumorigenic potential are reviewed and methods of biocompatibility testing discussed. Special emphasis is placed on impression materials, denture base resins and dental alloys. PMID:2269166

  11. Novel POSS-PCU Nanocomposite Material as a Biocompatible Coating for Quantum Dots.

    Science.gov (United States)

    Rizvi, Sarwat B; Yang, Shi Yu; Green, Mark; Keshtgar, Mo; Seifalian, Alexander M

    2015-12-16

    Quantum dots (QDs) are fluorescent nanoparticles with unique photophysical properties that enable them to potentially replace traditional organic dyes and fluorescent proteins in various bioimaging applications. However, the inherent toxicity of their cores based on cadmium salts limits their widespread biomedical use. We have developed a novel nanocomposite polymer emulsion based on polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) that can be used to coat quantum dots to nullify their toxicity and enhance photostability. Here we report the synthesis and characterization of a novel POSS-PCU nanocomposite polymer emulsion and describe its application for coating QDs for biological application. The polymer was synthesized by a process of emulsion polymerization and formed stable micelles of ∼33 nm in diameter. CdTe/CdS/ZnS QDs were efficiently stabilized by the polymer emulsion through encapsulation within the polymer micelles. Characterization studies showed no significant change in the unique photophysical properties of QDs after coating. The polymer was biocompatible to HepG2, HUVECs, and mouse skeletal muscle cells at 2.5% after 24 h exposure on in vitro testing. Polymer encapsulated QDs showed enhanced photostability on exposure to high degrees of UV irradiation and air as well as significantly reduced cytotoxicity on exposure to HepG2 cells at 30 μg/mL for 24 h. We have therefore concluded that the POSS-PCU polymer emulsion has the potential to make a biocompatible and photostable coating for QDs enabling a host of biomedical applications to take this technology to the next level. PMID:26439600

  12. Biocompatibility of mineral trioxide aggregate and three new endodontic cements: An animal study

    Directory of Open Access Journals (Sweden)

    Mohammad-Ghasem Aminozarbian

    2012-01-01

    Conclusion: According to the results of the current study, biocompatibility of CAAC and WOLCA cement were comparable with that of MTA, but CAAC Plus induced an inflammatory response higher than MTA, therefore is not biocompatible.

  13. Biocompatibility of acrylic resin after being soaked in sodium hypochlorite

    Directory of Open Access Journals (Sweden)

    Nike Hendrijatini

    2009-06-01

    Full Text Available Background: Acrylic resin as basic material for denture will stay on oral mucosa for a very long time. The polymerization of acrylic resin can be performed by conventional method and microwave, both produce different residual monomer at different toxicity. Acrylic resin can absorb solution, porous and possibly absorb disinfectantt as well, that may have toxic reaction with the tissue. Sodium Hypochlorite as removable denture disinfectant can be expected to be biocompatible to human body. The problem is how biocompatible acrylic resin which has been processed by conventional method and microwave method after being soaked in sodium hypochlorite solution. Purpose: The aim of this study was to understand in vitro biocompatibility of acrylic resin which has polimerated by conventional method and microwave after being soaked in sodium hypochlorite using tissue culture. Methods: Four groups of acrylic resin plate were produced, the first group was acrylic resin plate with microwave polymeration and soaked in sodium hypochlorite, the second group was acrylic resin plate with microwave polymeration but not soaked, the thirdwas one with conventional method and soaked and the last group was one with conventional method but not soaked, and in 1 control group. Each group consists of 7 plates. Biocompatibility test was performed in-vitro on each material using fibroblast tissue culture (BHK-21 cell-line. Result: The percentage between living cells and dead cells from materials which was given acrylic plate was wounted. The data was analyzed statistically with T test. Conclusion: The average value of living cells is higher in acrylic resin poimerization using microwave method compared to conventional method, in both soaked and non soaked (by sodium hypochlorite group. This means that sodium hypochlorite 0.5% was biocompatible to the mouth mucosa as removable denture disinfectant for 10 minutes soaking and washing afterwards.

  14. Biosynthesis of gold nanoparticles: A green approach.

    Science.gov (United States)

    Ahmed, Shakeel; Annu; Ikram, Saiqa; Yudha S, Salprima

    2016-08-01

    Nanotechnology is an immensely developing field due to its extensive range of applications in different areas of technology and science. Different types of methods are employed for synthesis of nanoparticles due to their wide applications. The conventional chemical methods have certain limitations with them either in the form of chemical contaminations during their syntheses procedures or in later applications and use of higher energy. During the last decade research have been focussed on developing simple, clean, non-toxic, cost effective and eco-friendly protocols for synthesis of nanoparticles. In order to get this objective, biosynthesis methods have been developed in order to fill this gap. The biosynthesis of nanoparticles is simple, single step, eco-friendly and a green approach. The biochemical processes in biological agents reduce the dissolved metal ions into nano metals. The various biological agents like plant tissues, fungi, bacteria, etc. are used for biosynthesis for metal nanoparticles. In this review article, we summarised recent literature on biosynthesis of gold nanoparticles which have revolutionised technique of synthesis for their applications in different fields. Due to biocompatibility of gold nanoparticles, it has find its applications in biomedical applications. The protocol and mechanism of biosynthesis of gold nanoparticles along with various applications have also been discussed. PMID:27236049

  15. Ion mediated targeting of cells with nanoparticles

    Science.gov (United States)

    Maheshwari, Vivek; Fu, Jinlong

    2010-03-01

    In eukaryotic cells, Ca^2+ ions are necessary for intracellular signaling, in activity of mitochondria and a variety of other cellular process that have been linked to cell apoptosis, proteins synthesis and cell-cycle regulation. Here we show that Ca^2+ ions, serving as the bio-compatible interface can be used to target Saccharomyces cerevisiae (SaC, baker's yeast), a model eukaryotic cell, with Au nanoparticles (10 nm). The Ca^2+ ions bind to the carboxylic acid groups in the citrate functionalized Au nanoparticles. This transforms the nanoparticles into micron long 1-D branched chain assemblies due to inter-particle dipole-dipole interaction and inter-particle bonding due to the divalent nature of the Ca^2+ ion. A similar transformation is observed with the use of divalent ions Mg^2+, Cd^2+ and Fe^2+. The 1-D assembly aids the interfacing of ion-nanoparticles on the cell by providing multiple contact points. Further monovalent ions such as Na^+ are also effective for the targeting of the cell with nanoparticles. However Na-Au nanoparticles are limited in their deposition as they exist in solution as single particles. The cells remain alive after the deposition process and their vitality is unaffected by the interfacing with ion-nanoparticles.

  16. Intelligent hydrophilic nanoparticles fabricated via alkaline hydrolysis of crosslinked polyacrylonitrile nanoparticles

    International Nuclear Information System (INIS)

    Crosslinked polyacrylonitrile (PAN) nanolatex, with an average hydrodynamic diameter of 84 nm and a polydispersity index of 0.06, was successfully synthesized at a high monomer concentration and low surfactant content via a modified emulsion polymerization. Three measurements were adopted to control the nucleation and growth processes. Taking advantage of the chemical activity of nitrile groups, intelligent hydrophilic polymeric nanoparticles were fabricated via simple alkaline hydrolysis treatment of the crosslinked PAN nanolatex. Dynamic light scattering, electrophoretic light scattering, FT-IR spectroscopy, elemental analysis, and TEM observations were used to monitor the changes in the composition, structure, and morphology of the nanoparticles during the hydrolysis process. The sizes, chemical composition, morphology, and pH-responsive behavior of the intelligent hydrophilic nanoparticles could be adjusted by simply changing the hydrolysis time. As the hydrolysis was prolonged, the following nanoparticles could be obtained, crosslinked PAN nanoparticles with hydrophilic surfaces, amphiphilic nanoparticles with a hydrophobic PAN core and a hydrophilic polymeric shell composed of acrylamide and acrylic acid units, or carboxylic polyacrylamide nanoparticles. These modified nanoparticles all display good hydrophilicity, good biocompatibility, pH-sensitivity, as well as carboxyl functional groups, and thus are ideal candidates for various biomedical applications

  17. Intelligent hydrophilic nanoparticles fabricated via alkaline hydrolysis of crosslinked polyacrylonitrile nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y., E-mail: zhyw@dhu.edu.cn; Wu, Q.; Zhang, H.; Zhao, J. [Donghua University, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Material Science and Engineering, Chemical Fibers Research Institute (China)

    2013-07-15

    Crosslinked polyacrylonitrile (PAN) nanolatex, with an average hydrodynamic diameter of 84 nm and a polydispersity index of 0.06, was successfully synthesized at a high monomer concentration and low surfactant content via a modified emulsion polymerization. Three measurements were adopted to control the nucleation and growth processes. Taking advantage of the chemical activity of nitrile groups, intelligent hydrophilic polymeric nanoparticles were fabricated via simple alkaline hydrolysis treatment of the crosslinked PAN nanolatex. Dynamic light scattering, electrophoretic light scattering, FT-IR spectroscopy, elemental analysis, and TEM observations were used to monitor the changes in the composition, structure, and morphology of the nanoparticles during the hydrolysis process. The sizes, chemical composition, morphology, and pH-responsive behavior of the intelligent hydrophilic nanoparticles could be adjusted by simply changing the hydrolysis time. As the hydrolysis was prolonged, the following nanoparticles could be obtained, crosslinked PAN nanoparticles with hydrophilic surfaces, amphiphilic nanoparticles with a hydrophobic PAN core and a hydrophilic polymeric shell composed of acrylamide and acrylic acid units, or carboxylic polyacrylamide nanoparticles. These modified nanoparticles all display good hydrophilicity, good biocompatibility, pH-sensitivity, as well as carboxyl functional groups, and thus are ideal candidates for various biomedical applications.

  18. Aggregation behaviour of gold nanoparticles in presence of chitosan

    International Nuclear Information System (INIS)

    Chitosan (CS) is a biocompatible polysaccharide with positive charge that is widely used as a coating agent for negatively charged nanoparticles. However, the types of structures that emerge by combining CS and nanoparticles as well as their behaviour are still poorly understood. In this work, we characterize the nanocomposites formed by gold nanoparticles (AuNPs) and CS and study the influence of CS in the expected aggregation process that should experience those nanoparticles under the favourable conditions of low pH and high ionic strength. Thus, at the working CS concentration, we observe the existence of CS structures that quickly trap the AuNPs and avoid the formation of nanoparticle aggregates in environmental conditions that, otherwise, would lead to such an aggregation

  19. Aggregation behaviour of gold nanoparticles in presence of chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Collado-González, Mar; Fernández Espín, Vanesa [University of Murcia, Department of Physical Chemistry (Spain); Montalbán, Mercedes G. [University of Murcia, Department of Chemical Engineering (Spain); Pamies, Ramón [Technical University of Cartagena, Department of Material Engineering and Manufacturing (Spain); Hernández Cifre, José Ginés; Díaz Baños, F. Guillermo, E-mail: fgb@um.es [University of Murcia, Department of Physical Chemistry (Spain); Víllora, Gloria [University of Murcia, Department of Chemical Engineering (Spain); García de la Torre, José [University of Murcia, Department of Physical Chemistry (Spain)

    2015-06-15

    Chitosan (CS) is a biocompatible polysaccharide with positive charge that is widely used as a coating agent for negatively charged nanoparticles. However, the types of structures that emerge by combining CS and nanoparticles as well as their behaviour are still poorly understood. In this work, we characterize the nanocomposites formed by gold nanoparticles (AuNPs) and CS and study the influence of CS in the expected aggregation process that should experience those nanoparticles under the favourable conditions of low pH and high ionic strength. Thus, at the working CS concentration, we observe the existence of CS structures that quickly trap the AuNPs and avoid the formation of nanoparticle aggregates in environmental conditions that, otherwise, would lead to such an aggregation.

  20. Physiologically important metal nanoparticles and their toxicity.

    Science.gov (United States)

    Sengupta, Jayeeta; Ghosh, Sourav; Datta, Poulami; Gomes, Aparna; Gomes, Antony

    2014-01-01

    Nanotechnology has been setting benchmarks for the last two decades, but the origins of this technology reach back to ancient history. Today, nanoparticles of both metallic and non-metallic origin are under research and development for applications in various fields of biology/therapeutics. Physiologically important metals are of concern because they are compatible with the human system in terms of absorption, assimilation, excretion, and side effects. There are several physiologically inorganic metals that are present in the human body with a wide range of biological activities. Some of these metals are magnesium, chromium, manganese, iron, cobalt, copper, zinc, selenium and molybdenum. These metals are synthesized in the form of nanoparticles by different physical and chemical methods. Physiologically important nanoparticles are currently under investigation for their bio-medical applications as well as for therapeutics. Along with the applicative aspects of nanoparticles, another domain that is of great concern is the risk assessment of these nanoparticles to avoid unnecessary hazards. It has been seen that these nanoparticles have been shown to possess toxicity in biological systems. Conventional physical and chemical methods of metal nanoparticle synthesis may be one possible reason for nanoparticle toxicity that can be overcome by synthesis of nanoparticles from biological sources. This review is an attempt to establish metal nanoparticles of physiological importance to be the best candidates for future nanotechnological tools and medicines, owing to the acceptability and safety in the human body. This can only be successful if these particles are synthesized with a better biocompatibility and low or no toxicity.

  1. 基于上转发光免疫层析技术的常见食源性致病菌快速检测方法研究与评价%Development of up-converting phosphor technology based lateral flow assay for quan-titative detection of foodborne pathogens

    Institute of Scientific and Technical Information of China (English)

    李春凤; 赵勇; 王晓英; 张平平; 刘晓; 孙崇云; 杨瑞馥; 王成彬; 周蕾

    2015-01-01

    Objective To develop an up-converting phosphor technology based lateral flow (UPT-LF) assay for rapid detection of Salmonella paratyphi A, S.paratyphi B, Escherichia coli O157 ∶H7 and Vibrio parahaemolyticus. Methods With up-converting phosphor nano-particles ( UCP-NPs ) as the bio-marker, four double-antibody-sandwich mode based UPT-LF strips for detecting the above mentioned four pathogens were prepared respectively and their sensitivi-ty, accuracy, linearity and specificity were evaluated .Furthermore, the feasibility of detecting bacteria in food samples was evaluated by different food samples artificially contaminated with less than 10 CFU target pathogens .Results The sensitivi-ty of UPT-LF assays for four pathogens was 105 ~106 CFU/ml with excellent specificity .The four strips had a good linear response with the linear fitting coefficient of determination (r) for each target pathogen ranging from 0.985 to 0.996.The positive rate of detecting pathogens from samples was acceptable .Conclusion The four developed UPT-LF strips provide a new choice for rapid , specific and sensitive and quantitative detection of S.paratyphi A , S.paratyphi B, E.coli O157∶H7 and V.parahemolyticus.%目的:研制针对4种常见食源性致病菌:甲型副伤寒沙门菌( Salmonella paratyphi A)、乙型副伤寒沙门菌(Salmonella paratyphi B)、大肠埃希菌O157∶H7(Escherichia coli O157∶H7)、副溶血弧菌(Vibrio parahaemolyticus)的基于上转发光免疫层析技术( UPT-LF)的快速定量检测试纸,并对其检测性能进行评价。方法以上转发光纳米颗粒( UCP-NPs)作为示踪物,基于双抗体夹心检测模型,研制针对上述4种靶标菌的UPT-LF试纸;以4种靶标菌的系列浓度标准菌悬液作为标准样品,评价试纸的敏感性、特异性、线性和精密性,并进行模拟染菌食品的检测,评价模拟样品阳性检出率。结果针对4种靶标菌的UPT-LF试纸均具

  2. Facile Synthesis of Uniform-Sized Bismuth Nanoparticles for CT Visualization of Gastrointestinal Tract in Vivo.

    Science.gov (United States)

    Wei, Boxiong; Zhang, Xuejun; Zhang, Cai; Jiang, Ying; Fu, Yan-Yan; Yu, Chunshui; Sun, Shao-Kai; Yan, Xiu-Ping

    2016-05-25

    High-performance and biocompatible contrast agents are the key to accurate diagnosis of various diseases in vivo via CT imaging. Fabrication of pure Bi nanoparticles is the best way to maximize X-ray absorption efficiency due to the ultrahigh X-ray attenuation ability of Bi and 100% content of Bi element. However, high-quality Bi nanoparticles prepared through a facile strategy are still lacking. Herein, we report a simple noninjection method to fabricate uniformly sized pure Bi nanoparticles using only two commercial reagents by simply heating the mixture of raw materials in a short time. The obtained Bi nanoparticles owned highly uniform size, excellent monodispersity, and impressive antioxidant capacity. After being modified with oligosaccharide, the "sweet" Bi nanoprobe with comfortable patient experience and favorable biocompatibility was successfully used in CT visualization of gastrointestinal tract in detail.

  3. A broadband-sensitive upconverter La(Ga{sub 0.5}Sc{sub 0.5})O{sub 3}:Er,Ni,Nb for crystalline silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Yasuhiko, E-mail: takeda@mosk.tytlabs.co.jp; Mizuno, Shintaro; Luitel, Hom Nath; Tani, Toshihiko [Toyota Central Research and Development Laboratories, Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

    2016-01-25

    We have developed an upconverter that significantly broadens the sensitive range, to overcome the shortcoming that conventional Er{sup 3+}-doped upconverters used for crystalline silicon solar cells can utilize only a small portion of the solar spectrum at around 1.55 μm. We have designed the combination of the sensitizers and host material to utilize photons not absorbed by silicon or Er{sup 3+} ions. Ni{sup 2+} ions have been selected as the sensitizers that absorb photons in the wavelength range between the silicon absorption edge (1.1 μm) and the Er{sup 3+} absorption band and transfer the energies to the Er{sup 3+} emitters, with La(Ga,Sc)O{sub 3} as the host material. The Ga to Sc ratio has been optimized to tune the location of the Ni{sup 2+} absorption band for sufficient energy transfer. Co-doping with Nb{sup 5+} ions is needed for charge balance to introduce divalent Ni{sup 2+} ions into the trivalent Ga{sup 3+} and Sc{sup 3+} sites. In addition to 1.45–1.58 μm photons directly absorbed by the Er{sup 3+} ions, we have demonstrated upconversion of 1.1–1.35 μm photons in the Ni{sup 2+} absorption band to 0.98 μm photons, using 10% Er, 0.5% Ni, and 0.5% Nb-doped La(Ga{sub 0.5}Sc{sub 0.5})O{sub 3}. The broadband-sensitive upconverter developed here can improve conversion efficiency of crystalline silicon solar cells more notably than conventional ones.

  4. Biodegradable/biocompatible coated metal implants for orthopedic applications.

    Science.gov (United States)

    Saleh, Mohamed M; Touny, A H; Al-Omair, Mohammed A; Saleh, M M

    2016-05-12

    Biocompatible metals have been suggested as revolutionary biomaterials for bone-grafting therapies. Although metals and their alloys are widely and successfully used in producing biomedical implants due to their good mechanical properties and corrosion resistance, they have a lack in bioactivity. Therefore coating of the metal surface with calcium phosphates (CaP) is a benign way to achieve well bioactivity and get controlled corrosion properties. The biocompatibility and bioactivity calcium phosphates (CaP) in bone growth were guided them to biomedical treatment of bone defects and fractures. Many techniques have been used for fabrication of CaP coatings on metal substrates such as magnesium and titanium. The present review will focus on the synthesis of CaP and their relative forms using different techniques especially electrochemical techniques. The latter has always been known of its unique way of optimizing the process parameters that led to a control in the structure and characteristics of the produced materials. PMID:27175470

  5. High concentration honey chitosan electrospun nanofibers: biocompatibility and antibacterial effects.

    Science.gov (United States)

    Sarhan, Wessam A; Azzazy, Hassan M E

    2015-05-20

    Honey nanofibers represent an attractive formulation with unique medicinal and wound healing advantages. Nanofibers with honey concentrations of chitosan and honey (H) were cospun with polyvinyl alcohol (P) allowing the fabrication of nanofibers with high honey concentrations up to 40% and high chitosan concentrations up to 5.5% of the total weight of the fibers using biocompatible solvents (1% acetic acid). The fabricated nanofibers were further chemically crosslinked, by exposure to glutaraldehyde vapor, and physically crosslinked by heating and freezing/thawing. The new HP-chitosan nanofibers showed pronounced antibacterial activity against Staphylococcus aureus but weak antibacterial activity against Escherichia coli. The developed HP-chitosan nanofibers revealed no cytotoxicity effects on cultured fibroblasts. In conclusion, biocompatible, antimicrobial crosslinked honey/polyvinyl alcohol/chitosan nanofibers were developed which hold potential as effective wound dressing. PMID:25817652

  6. Biocompatibility of Compounds of Extracellular Matrix and Thermally Reversible Hydrogel

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new scaffold material composed of extracellular matrix (ECM) and thermal sensitive hydrogel (HG), and evaluated its biocompatibility were investigated. We cultured bladder smooth muscle cells with this compound material, and then observed with phase contrast microscopy and scanning electron microscope (SEM) to assess the cell growth and morphology. The cell adhesion and proliferation were detected with MTT assay and cell count. Results show the ECM/HG compounds appeared as a net-like and red-stained construction with enough meshes and without any cellular fragments. 6 h after implantation, cells were observed adhere on the compounds and extend spurious along the fibers 12 h later. Under SEM even some ECM was observed to be secreted. MTT assay shows there was obvious statistic difference among 3 groups (P<0.05).ECM/HG compound materials show a good biocompatibility, which confirms that it would be an ideal tissue engineering scaffolds.

  7. BIOCOMPATIBLE FLUORESCENT MICROSPHERES: SAFE PARTICLES FOR MATERIAL PENETRATION STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Farquar, G; Leif, R

    2009-07-15

    Biocompatible polymers with hydrolyzable chemical bonds have been used to produce safe, non-toxic fluorescent microspheres for material penetration studies. The selection of polymeric materials depends on both biocompatibility and processability, with tailored fluorescent properties depending on specific applications. Microspheres are composed of USFDA-approved biodegradable polymers and non-toxic fluorophores and are therefore suitable for tests where human exposure is possible. Micropheres were produced which contain unique fluorophores to enable discrimination from background aerosol particles. Characteristics that affect dispersion and adhesion can be modified depending on use. Several different microsphere preparation methods are possible, including the use of a vibrating orifice aerosol generator (VOAG), a Sono-Tek atomizer, an emulsion technique, and inkjet printhead. Applications for the fluorescent microspheres include challenges for biodefense system testing, calibrants for biofluorescence sensors, and particles for air dispersion model validation studies.

  8. [IN VIVO EVALUATION OF POLYCAPROLACTONE-HYDROXYAPATITE SCAFFOLD BIOCOMPATIBILITY].

    Science.gov (United States)

    Ivanov, A N; Kozadaev, M N; Bogomolova, N V; Matveeva, O V; Puchinyan, D M; Norkin, I A; Sal'kovskii, Yu E; Lyubun, G P

    2015-01-01

    Biocompatibility is one of the main and very important properties for scaffolds. The aim of the present study was to investigate cells population dynamics in vivo in the process of original polycaprolactone-hydroxyapatite scaffold colonization, as well as tissue reactions to the implantation to assess the biocompatibility of the matrix. It has been found that tissue reactive changes in white rats subside completely up to the 21st day after subcutaneous polycaprolactone-hydroxyapatite scaffold implantation. Matrix was actively colonized by connective tissue cells in the period from the 7th to the 21st day of the experiment. However, intensive scaffold vascularization started from the 14th day after implantation. These findings suggest a high degree of the polycaprolactone-hydroxyapatite scaffold biocompatiblilitye.

  9. Biocompatibility studies of polyacrylonitrile membranes modified with carboxylated polyetherimide.

    Science.gov (United States)

    Senthilkumar, S; Rajesh, S; Jayalakshmi, A; Mohan, D

    2013-10-01

    Poly (ether-imide) (PEI) was carboxylated and used as the hydrophilic modification agent for the preparation of polyacrylonitrile (PAN) membranes. Membranes were prepared with different blend compositions of PAN and CPEI by diffusion induced precipitation. The modified membranes were characterized by thermo gravimetric analysis (TGA), mechanical analysis, scanning electron microscopy (SEM) and contact angle measurement to understand the influence of CPEI on the properties of the membranes. The biocompatibility studies exhibited reduced plasma protein adsorption, platelet adhesion and thrombus formation on the modified membrane surface. The complete blood count (CBC) results of CPEI incorporated membranes showed stable CBC values and significant decrease in the complement activation were also observed. In addition to good cytocompatibility, monocytes cultured on these modified membranes exhibited improved functional profiles in 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. Thus it could be concluded that PAN/CPEI membranes with excellent biocompatibility can be useful for hemodialysis. PMID:23910257

  10. Biocompatibility of intracortical microelectrodes: current status and future prospects

    Directory of Open Access Journals (Sweden)

    Cristina Marin

    2010-05-01

    Full Text Available Rehabilitation of sensory and/or motor functions in patients with neurological diseases is more and more dealing with artificial electrical stimulation and recording from populations of neurons using biocompatible chronic implants. As more and more patients have benefited from these approaches, the interest in neural interfaces has grown significantly. However an important problem reported with all available microelectrodes to date is long-term viability and biocompatibility. Therefore it is essential to understand the signals that lead to neuroglial activation and create a targeted intervention to control the response, reduce the adverse nature of the reactions and maintain an ideal environment for the brain-electrode interface. We discuss some of the exciting opportunities and challenges that lie in this intersection of neuroscience research, bioengineering, neurology and biomaterials.

  11. Interfacing Microbial Styrene Production with a Biocompatible Cyclopropanation Reaction**

    OpenAIRE

    Wallace, Stephen; Balskus, Emily P.

    2015-01-01

    Introducing new reactivity into living organisms is a major challenge in synthetic biology. Despite an increasing interest in both developing aqueous-compatible small molecule catalysts and engineering enzymes to perform new chemistry in vitro, the integration of non-native reactivity into metabolic pathways for small molecule production has been underexplored. Herein we report a biocompatible iron(III) phthalocyanine catalyst capable of efficient olefin cyclopropanation in the presence of a ...

  12. Physical and technological principles of creating biocompatible superparamagnetic particles.

    Science.gov (United States)

    Levitin, Yevgen; Koval, Alla; Vedernikova, Irina; Ol'khovik, Larissa; Tkachenko, Mykola

    2011-01-01

    Nanodisperse powder of zinc-substituted magnetite has been developed. Functional characteristics (biocompatibility, dispersion, magnetic state) allow to recommend it for approbation in medical and biologic technologies. The character of the temperature dependences of magnetization investigated in the magnetic fields lower than the anisotropy field indicates that transfer from the magnetically stable state into the superparamagnetic state was realized for particles of 3-13 nm in the temperature range of 4.2-150 K. It reflects specificity of small particles magnetism.

  13. Biocompatible polymer microarrays for cellular high-content screening

    OpenAIRE

    Pernagallo, Salvatore

    2010-01-01

    The global aim of this thesis was to study the use of microarray technology for the screening and identification of biocompatible polymers, to understand physiological phenomena, and the design of biomaterials, implant surfaces and tissue-engineering scaffolds. This work was based upon the polymer microarray platform developed by the Bradley group. Polymer microarrays were successfully applied to find the best polymer supports for: (i) mouse fibroblast cells and used to eval...

  14. Biomolecular modification of zirconia surfaces for enhanced biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Shih-Kuang; Hsu, Hsueh-Chuan [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China); Ho, Wen-Fu [Department of Chemical and Materials Engineering, National University of Kaohsiung, Taiwan, ROC (China); Yao, Chun-Hsu [Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung 40402, Taiwan, ROC (China); Chang, Pai-Ling [Taoyuan General Hospital, Taoyuan 33004, Taiwan, ROC (China); Wu, Shih-Ching, E-mail: scwu@ctust.edu.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China)

    2014-12-01

    Yttria-tetragonal zirconia polycrystal (Y-TZP) is a preferred biomaterial due to its good mechanical properties. In order to improve the biocompatibility of zirconia, RGD-peptide derived from extracellular matrix proteins was employed to modify the surface of Y-TZP to promote cell adhesion in this study. The surface of Y-TZP specimens was first modified using a hydrothermal method for different lengths of time. The topographies of modified Y-TZP specimens were analyzed by contact angle, XRD, FTIR, AFM, and FE-SEM. The mechanical properties were evaluated using Vickers hardness and three point bending strength. Then, the RGD-peptide was immobilized on the surface of the Y-TZP by chemical treatment. These RGD-peptide immobilized Y-TZP specimens were characterized by FTIR and AFM, and then were cocultured with MG-63 osteoblast cells for biocompatibility assay. The cell morphology and proliferation were evaluated by SEM, WST-1, and ALP activity assay. The XRD results indicated that the phase transition, from tetragonal phase to monoclinic phase, was increased with a longer incubation time of hydrothermal treatment. However, there were no significant differences in mechanical strengths after RGD-peptide was successfully grafted onto the Y-TZP surface. The SEM images showed that the MG-63 cells appeared polygonal, spindle-shaped, and attached on the RGD-peptide immobilized Y-TZP. The proliferation and cellular activities of MG-63 cells on the RGD-peptide immobilized Y-TZP were better than that on the unmodified Y-TZP. From the above results, the RGD-peptide can be successfully grafted onto the hydrothermal modified Y-TZP surface. The RGD-peptide immobilized Y-TZP can increase cell adhesion, and thus, improve the biocompatibility of Y-TZP. - Highlights: • Covalent bonding between peptide and Y-TZP was proposed. • Stable biomimetic structures produced on the surface of zirconia. • The biocompatibility was improved.

  15. Nanocellulose for Biomedical Applications : Modification, Characterisation and Biocompatibility Studies

    OpenAIRE

    Hua, Kai

    2015-01-01

    In the past decade there has been increasing interest in exploring the use of nanocellulose in medicine. However, the influence of the physicochemical properties of nanocellulose on the material´s biocompatibility has not been fully investigated.  In this thesis, thin films of nanocellulose from wood (NFC) and from Cladophora algae (CC) were modified by the addition of charged groups on their surfaces and the influence of these modifications on the material´s physicochemical properties and on...

  16. Drug loading and release on tumor cells using silk fibroin–albumin nanoparticles as carriers

    International Nuclear Information System (INIS)

    Polymeric and biodegradable nanoparticles are frequently used in drug delivery systems. In this study silk fibroin–albumin blended nanoparticles were prepared using the desolvation method without any surfactant. These nanoparticles are easily internalized by the cells, reside within perinuclear spaces and act as carriers for delivery of the model drug methotrexate. Methotrexate loaded nanoparticles have better encapsulation efficiency, drug loading ability and less toxicity. The in vitro release behavior of methotrexate from the nanoparticles suggests that about 85% of the drug gets released after 12 days. The encapsulation and loading of a drug would depend on factors such as size, charge and hydrophobicity, which affect drug release. MTT assay and conjugation of particles with FITC demonstrate that the silk fibroin–albumin nanoparticles do not affect the viability and biocompatibility of cells. This blended nanoparticle, therefore, could be a promising nanocarrier for the delivery of drugs and other bioactive molecules. (paper)

  17. Biocompatible two-layer tantalum/titania-polymer hybrid coating.

    Science.gov (United States)

    Cortecchia, Elisa; Pacilli, Annalisa; Pasquinelli, Gianandrea; Scandola, Mariastella

    2010-09-13

    Using a two-step procedure, radiopaque and biocompatible coatings were obtained, consisting of a tantalum layer deposited by sputtering technique and of an upper organic-inorganic hybrid layer synthesized via sol-gel. As shown by radiographic images, tantalum confers to plastic substrates good X-ray visibility, adjustable via control of deposition time, but its adhesion to the substrate is poor and manipulation easily damages the metal layer. Polymer-titania hybrid coatings, synthesized using poly-ε-caprolactone (PCL) or carboxy-terminated polydimethylsiloxane (PDMS) as organic precursors, were applied on the metal layer as biocompatible protective coatings. Biocompatibility is demonstrated by cytotoxicity tests conducted using vascular wall resident-mesenchymal stem cells (VW-MSCs). Both coatings show very good adhesion to the substrate, showing no sign of detachment upon large substrate deformations. Under such conditions, SEM observations show that the PCL-containing hybrid forms cracks, whereas the PDMS-based hybrid does not crack, suggesting possible applications of the latter material as a protective layer of sputtered tantalum radiopaque markers for flexible medical devices. PMID:20831278

  18. A biodegradable and biocompatible gecko-inspired tissue adhesive.

    Science.gov (United States)

    Mahdavi, Alborz; Ferreira, Lino; Sundback, Cathryn; Nichol, Jason W; Chan, Edwin P; Carter, David J D; Bettinger, Chris J; Patanavanich, Siamrut; Chignozha, Loice; Ben-Joseph, Eli; Galakatos, Alex; Pryor, Howard; Pomerantseva, Irina; Masiakos, Peter T; Faquin, William; Zumbuehl, Andreas; Hong, Seungpyo; Borenstein, Jeffrey; Vacanti, Joseph; Langer, Robert; Karp, Jeffrey M

    2008-02-19

    There is a significant medical need for tough biodegradable polymer adhesives that can adapt to or recover from various mechanical deformations while remaining strongly attached to the underlying tissue. We approached this problem by using a polymer poly(glycerol-co-sebacate acrylate) and modifying the surface to mimic the nanotopography of gecko feet, which allows attachment to vertical surfaces. Translation of existing gecko-inspired adhesives for medical applications is complex, as multiple parameters must be optimized, including: biocompatibility, biodegradation, strong adhesive tissue bonding, as well as compliance and conformability to tissue surfaces. Ideally these adhesives would also have the ability to deliver drugs or growth factors to promote healing. As a first demonstration, we have created a gecko-inspired tissue adhesive from a biocompatible and biodegradable elastomer combined with a thin tissue-reactive biocompatible surface coating. Tissue adhesion was optimized by varying dimensions of the nanoscale pillars, including the ratio of tip diameter to pitch and the ratio of tip diameter to base diameter. Coating these nanomolded pillars of biodegradable elastomers with a thin layer of oxidized dextran significantly increased the interfacial adhesion strength on porcine intestine tissue in vitro and in the rat abdominal subfascial in vivo environment. This gecko-inspired medical adhesive may have potential applications for sealing wounds and for replacement or augmentation of sutures or staples.

  19. Sputtered Gum metal thin films showing bacterial inactivation and biocompatibility.

    Science.gov (United States)

    Achache, S; Alhussein, A; Lamri, S; François, M; Sanchette, F; Pulgarin, C; Kiwi, J; Rtimi, S

    2016-10-01

    Super-elastic Titanium based thin films Ti-23Nb-0.7Ta-2Zr-(O) (TNTZ-O) and Ti-24Nb-(N) (TN-N) (at.%) were deposited by direct current magnetron sputtering (DCMS) in different reactive atmospheres. The effects of oxygen doping (TNTZ-O) and/or nitrogen doping (TN-N) on the microstructure, mechanical properties and biocompatibility of the as-deposited coatings were investigated. Nano-indentation measurements show that, in both cases, 1sccm of reactive gas in the mixture is necessary to reach acceptable values of hardness and Young's modulus. Mechanical properties are considered in relation to the films compactness, the compressive stress and the changes in the grain size. Data on Bacterial inactivation and biocompatibility are reported in this study. The biocompatibility tests showed that O-containing samples led to higher cells proliferation. Bacterial inactivation was concomitant with the observed pH and surface potential changes under light and in the dark. The increased cell fluidity leading to bacterial lysis was followed during the bacterial inactivation time. The increasing cell wall fluidity was attributed to the damage of the bacterial outer cell which losing its capacity to regulate the ions exchange in and out of the bacteria. PMID:27434155

  20. Biocompatibility of Chitosan Carriers with Application in Drug Delivery

    Directory of Open Access Journals (Sweden)

    Ana Grenha

    2012-09-01

    Full Text Available Chitosan is one of the most used polysaccharides in the design of drug delivery strategies for administration of either biomacromolecules or low molecular weight drugs. For these purposes, it is frequently used as matrix forming material in both nano and micron-sized particles. In addition to its interesting physicochemical and biopharmaceutical properties, which include high mucoadhesion and a great capacity to produce drug delivery systems, ensuring the biocompatibility of the drug delivery vehicles is a highly relevant issue. Nevertheless, this subject is not addressed as frequently as desired and even though the application of chitosan carriers has been widely explored, the demonstration of systems biocompatibility is still in its infancy. In this review, addressing the biocompatibility of chitosan carriers with application in drug delivery is discussed and the methods used in vitro and in vivo, exploring the effect of different variables, are described. We further provide a discussion on the pros and cons of used methodologies, as well as on the difficulties arising from the absence of standardization of procedures.

  1. New magnetic fluid developed with natural organic compounds biocompatible.

    Science.gov (United States)

    Santos, J G; Silveira, L B; Fegueredo, P H S; Araújo, B F; Peternele, W S; Rodriguez, A F R; Vilela, E C; Garg, V K; Oliveira, A C; Azevedo, R B; Morais, P C

    2012-06-01

    This work was developed with an aqueous suspension of maghemite nanoparticles and colloidal emulsions with nanoparticles of magnetite. The nanoparticles were synthesized by co-precipitation method. The first was the magnetic emulsion nanoparticles of maghemite dispersed in the aqueous extract obtained from the leaf embauba (Cecropia Obtusifolia), whose tree is native to Central and South America. Thereby achieving the magnetic fluid extract embauba stabilized with ionic buffer solution pH 7.4. A second emulsion was prepared with colloidal magnetite nanoparticles with surfaces previously coated with oleic acid as a means of dispersing and using the oil extracted from in nature seed Andiroba (Carapa Guianensis), tree of the Brazilian Amazon. These new magnetic fluids the nanoparticles were characterized by Photoacoustic spectroscopy (PAS) to determine the coating layer of molecules on the surfaces of nanoparticles. In aqueous ionic magnetic fluid Cecropia Obtusifolia (MFCO) chlorogenic acid contributes to the electron density in the presence of four groups alcohols, a ketone group and a carboxylic group. In magnetic fluid-based oil andiroba MFAD PAS spectra show that oleic acid molecules are tightly linked on the surface of the nanoparticles. PMID:22905527

  2. Au-Biocompatible metallic nanostructures in metalloprotein electrochemistry and electrocatalysis

    DEFF Research Database (Denmark)

    Jensen, Palle Skovhus; Engelbrekt, Christian; Sørensen, Karsten Holm;

    2012-01-01

    Molecular scale metallic nanoparticles coated by molecular monolayers and immobilized on single-crystal Au-electrode surfaces are efficient catalysts in metalloprotein voltammetry. Nanoparticles prepared by a new ‘‘green’’ method also exhibit strong electrocatalysis in both protein electrochemist...

  3. Bifunctional silica nanoparticles for the exploration of biofilms of Pseudomonas aeruginosa

    OpenAIRE

    Mauline, Léïla; Gressier, Marie; Roques, Christine; Hammer, Peter,; Ribeiro, Sidney J. L.; Caiut, José Maurício A.; Menu, Marie-Joëlle

    2013-01-01

    Luminescent silica nanoparticles are frequently employed for biotechnology applications mainly because of their easy functionalization, photo-stability, and biocompatibility. Bifunctional silica nanoparticles (BSNPs) are described here as new efficient tools for investigating complex biological systems such as biofilms. Photoluminescence is brought about by the incorporation of a silylated ruthenium (II) complex. The surface properties of the silica particles were designed by reaction with am...

  4. Characterization of Silver Nanoparticle In Situ Synthesis on Porous Sericin Gel for Antibacterial Application

    OpenAIRE

    Gang Tao; Lina Liu; Yejing Wang; Huaipu Chang; Ping Zhao; Hua Zuo; Huawei He

    2016-01-01

    Sericin from Bombyx mori cocoon has good hydrophilicity, reaction activity, biocompatibility, and biodegradability, which has shown great potentials for biomedical materials. Here, an ultraviolet light-assisted in situ synthesis approach is developed to immobilize silver nanoparticles on the surface of sericin gel. The amount of silver nanoparticles immobilized on the surface of sericin gel could be regulated by the irradiation time. The porous structure and property of sericin gel were not a...

  5. Investigation of adding fluoroapatite nanoparticles on compressive strength and corrosion behaviour of dental amalgams

    OpenAIRE

    Fahimeh Mirlohi; Ali Doostmohammadi; Ahmad Monshi

    2012-01-01

    In recent years, there have been many efforts to improve biological and biocompatibility features of amalgam. The aim of this research was investigating the effect of adding fluoroapatite (FA) nanoparticles on compressive strength and corrosion behaviour of dental amalgam. An amalgam alloy powder was mixed with 1, 3 and 5 wt.% of FA nanoparticles to form composite powders. Compressive strength of the corresponding dental amalgam samples was measured on the first and seventh day after preparat...

  6. Biological synthesis of fluorescent nanoparticles by cadmium and tellurite resistant Antarctic bacteria: exploring novel natural nanofactories

    OpenAIRE

    Plaza, D. O.; Gallardo, C.; Straub, Y. D.; Bravo, D.; Pérez-Donoso, J. M.

    2016-01-01

    Background Fluorescent nanoparticles or quantum dots (QDs) have been intensely studied for basic and applied research due to their unique size-dependent properties. There is an increasing interest in developing ecofriendly methods to synthesize these nanoparticles since they improve biocompatibility and avoid the generation of toxic byproducts. The use of biological systems, particularly prokaryotes, has emerged as a promising alternative. Recent studies indicate that QDs biosynthesis is rela...

  7. Biocompatible Fluorescent Core-Shell Nanoconjugates Based on Chitosan/Bi2S3 Quantum Dots.

    Science.gov (United States)

    Ramanery, Fábio P; Mansur, Alexandra A P; Mansur, Herman S; Carvalho, Sandhra M; Fonseca, Matheus C

    2016-12-01

    Bismuth sulfide (Bi2S3) is a narrow-bandgap semiconductor that is an interesting candidate for fluorescent biomarkers, thermoelectrics, photocatalysts, and photovoltaics. This study reports the synthesis and characterization of novel Bi2S3 quantum dots (QDs) functionalized using chitosan (CHI) as the capping ligands via aqueous "green" route at room temperature and ambient pressure. Transmission electron microscopy (TEM), UV-visible (UV-vis) spectroscopy, photoluminescence (PL) spectroscopy, dynamic light scattering (DLS), and zeta potential (ZP) analysis were used to characterize the hybrids made of biopolymer-functionalized Bi2S3 semiconductor nanocrystals. The results demonstrated that the CHI ligand was effective at nucleating and controlling the growth of water-soluble colloidal Bi2S3 nanoparticles. The average sizes of the Bi2S3 nanoparticles were significantly affected by the molar ratio of the precursors but less dependent on the pH of the aqueous media, leading to the formation of nanocrystals with average diameters varying from 4.2 to 6.7 nm. These surface-modified Bi2S3 nanocrystals with CHI exhibited photoluminescence in the visible spectral region. Moreover, the results of in vitro MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide) assay with human osteosarcoma cells (SAOS) cell line demonstrated no cytotoxic response of the nanoconjugates.Furthermore, the results indicated that the Bi2S3 QD-CHI nanoconjugates showed HEK293T cell uptake; therefore, they can be potentially used as novel fluorescent nanoprobes for the in vitro bioimaging of cells in biomedical applications. Graphical Abstract Schematic representation of the biocompatible core-shell nanostructure of the chitosan/Bi2S3 quantum dot conjugates with photoluminescent properties.

  8. Biocompatible Fluorescent Core-Shell Nanoconjugates Based on Chitosan/Bi2S3 Quantum Dots.

    Science.gov (United States)

    Ramanery, Fábio P; Mansur, Alexandra A P; Mansur, Herman S; Carvalho, Sandhra M; Fonseca, Matheus C

    2016-12-01

    Bismuth sulfide (Bi2S3) is a narrow-bandgap semiconductor that is an interesting candidate for fluorescent biomarkers, thermoelectrics, photocatalysts, and photovoltaics. This study reports the synthesis and characterization of novel Bi2S3 quantum dots (QDs) functionalized using chitosan (CHI) as the capping ligands via aqueous "green" route at room temperature and ambient pressure. Transmission electron microscopy (TEM), UV-visible (UV-vis) spectroscopy, photoluminescence (PL) spectroscopy, dynamic light scattering (DLS), and zeta potential (ZP) analysis were used to characterize the hybrids made of biopolymer-functionalized Bi2S3 semiconductor nanocrystals. The results demonstrated that the CHI ligand was effective at nucleating and controlling the growth of water-soluble colloidal Bi2S3 nanoparticles. The average sizes of the Bi2S3 nanoparticles were significantly affected by the molar ratio of the precursors but less dependent on the pH of the aqueous media, leading to the formation of nanocrystals with average diameters varying from 4.2 to 6.7 nm. These surface-modified Bi2S3 nanocrystals with CHI exhibited photoluminescence in the visible spectral region. Moreover, the results of in vitro MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide) assay with human osteosarcoma cells (SAOS) cell line demonstrated no cytotoxic response of the nanoconjugates.Furthermore, the results indicated that the Bi2S3 QD-CHI nanoconjugates showed HEK293T cell uptake; therefore, they can be potentially used as novel fluorescent nanoprobes for the in vitro bioimaging of cells in biomedical applications. Graphical Abstract Schematic representation of the biocompatible core-shell nanostructure of the chitosan/Bi2S3 quantum dot conjugates with photoluminescent properties. PMID:27067735

  9. Enhanced biocompatibility of ZnS:Mn quantum dots encapsulated with Aloe vera extract for therapeutic applications

    Science.gov (United States)

    Anilkumar, M.; Bindu, K. R.; Sneha Saj, A.; Anila, E. I.

    2016-08-01

    Toxicity of nanoparticles remains to be a major issue in their application to the biomedical field. Aloe vera (AV) is one of the most widely exploited medicinal plants that have a multitude of amazing properties in the field of medicine. Methanol extract of Aloe vera can be used as a novel stabilising agent for quantum dots to reduce toxicity. We report the synthesis, structural characterization, antibacterial activity and cytotoxicity studies of ZnS:Mn quantum dots synthesized by the colloidal precipitation method, using methanol extract of Aloe vera (AVME) as the capping agent. The ZnS:Mn quantum dots capped with AVME exhibit superior performances in biocompatibility and antibacterial activity compared with ZnS:Mn quantum dots without encapsulation. Project supported by the Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Government of India.

  10. Evaluation of up-converting phosphor technology-based lateral flow strips for rapid detection of Bacillus anthracis Spore, Brucella spp., and Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Pingping Zhang

    Full Text Available Bacillus anthracis, Brucella spp., and Yersinia pestis are zoonotic pathogens and biowarfare- or bioterrorism-associated agents that must be detected rapidly on-site from various samples (e.g., viscera and powders. An up-converting phosphor technology-based lateral flow (UPT-LF strip was developed as a point-of-care testing (POCT to satisfy the requirements of first-level emergency response. We developed UPT-LF POCT to quantitatively detect the three pathogens within 15 min. Sample and operation-error tolerances of the assay were comprehensively evaluated. The sensitivity of UPT-LF assay to bacterial detection reached 10(4 cfu · mL(-1 (100 cfu/test, with a linear quantitative range of 4 to 6 orders of magnitude. Results revealed that the UPT-LF assay exhibited a high specificity with the absence of false-positive results even at 10(9 cfu · mL(-1 of non-specific bacterial contamination. The assay could tolerate samples with a wide pH range (2 to 12, high ion strengths (≥ 4 mol · L(-1 of NaCl, high viscosities (≤ 25 mg · mL(-1 of PEG20000 or ≥ 20% of glycerol, and high concentrations of bio-macromolecule (≤ 200 mg · mL(-1 of bovine serum albumin or ≥ 80 mg · mL(-1 of casein. The influence of various types of powders and viscera (fresh and decomposed on the performance of UPT-LF assay was determined. The operational error of liquid measurement exhibited few effects on sensitivity and specificity. The developed UPT-LF POCT assay is applicable under field conditions with excellent tolerance to sample complexity and operational error.

  11. Regulating Biocompatibility of Carbon Spheres via Defined Nanoscale Chemistry and a Careful Selection of Surface Functionalities

    Science.gov (United States)

    Misra, Santosh K.; Chang, Huei-Huei; Mukherjee, Prabuddha; Tiwari, Saumya; Ohoka, Ayako; Pan, Dipanjan

    2015-10-01

    A plethora of nanoarchitectures have been evaluated preclincially for applications in early detection and treatment of diseases at molecular and cellular levels resulted in limited success of their clinical translation. It is important to identify the factors that directly or indirectly affect their use in human. We bring a fundamental understanding of how to adjust the biocompatibility of carbon based spherical nanoparticles (CNPs) through defined chemistry and a vigilant choice of surface functionalities. CNPs of various size are designed by tweaking size (2-250 nm), surface chemistries (positive, or negatively charged), molecular chemistries (linear, dendritic, hyperbranched) and the molecular weight of the coating agents (MW 400-20 kDa). A combination of in vitro assays as tools were performed to determine the critical parameters that may trigger toxicity. Results indicated that hydrodynamic sizes are potentially not a risk factor for triggering cellular and systemic toxicity, whereas the presence of a highly positive surface charge and increasing molecular weight enhance the chance of inducing complement activation. Bare and carboxyl-terminated CNPs did present some toxicity at the cellular level which, however, is not comparable to those caused by positively charged CNPs. Similarly, negatively charged CNPs with hydroxyl and carboxylic functionalities did not cause any hemolysis.

  12. Evaluation of Synthesized Nanohydroxyapatite-Nanocellulose Composites as Biocompatible Scaffolds for Applications in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Claudia S. Herdocia-Lluberes

    2015-01-01

    Full Text Available Basic calcium phosphate (BCP crystals have been associated with many diseases due to their activation of signaling pathways that lead to their mineralization and deposition in intra-articular and periarticular locations in the bones. In this study, hydroxyapatite (HAp has been placed in a polysaccharide network as a strategy to minimize this deposition. This research consisted of the evaluation of varying proportions of the polysaccharide network, cellulose nanocrystals (CNCs, and HAp synthesized via a simple sol-gel method. The resulting biocompatible composites were extensively characterized by means of thermogravimetric analysis (TGA, powder X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, dynamic light scattering (DLS, zeta potential, and scanning electron microscopy (SEM. It was found that an nHAp = CNC ratio presented greater homogeneity in the size and distribution of the nanoparticles without compromising the crystalline structure. Also, incorporation of bone morphogenetic protein 2 (BMP-2 was performed to evaluate the effects that this interaction would have in the constructs. Finally, the osteoblast cell (hFOB 1.19 viability assay was executed and it showed that all of the materials promoted greater cell proliferation while the nHAp > CNC proportion with the inclusion of the BMP-2 protein was the best composite for the purpose of this study.

  13. Controllable fabrication and characterization of biocompatible core-shell particles and hollow capsules as drug carrier

    Science.gov (United States)

    Hao, Lingyun; Gong, Xinglong; Xuan, Shouhu; Zhang, Hong; Gong, Xiuqing; Jiang, Wanquan; Chen, Zuyao

    2006-10-01

    SiO 2@CdSe core-shell particles were fabricated by controllable deposition CdSe nanoparticles on silica colloidal spheres. Step-wise coating process was tracked by the TEM and XRD measurements. In addition, SiO 2@CdSe/polypyrrole(PPy) multi-composite particles were synthesized based on the as-prepared SiO 2@CdSe particles by cationic polymerization. The direct electrochemistry of myoglobin (Mb) could be performed by immobilizing Mb on the surface of SiO 2@CdSe particles. Immobilized with Mb, SiO 2@CdSe/PPy-Mb also displayed good bioelectrochemical activity. It confirmed the good biocompatible property of the materials with protein. CdSe hollow capsules were further obtained as the removal of the cores of SiO 2@CdSe spheres. Hollow and porous character of CdSe sub-meter size capsules made them becoming hopeful candidates as drug carriers. Doxorubicin, a typical an antineoplastic drug, was introduced into the capsules. A good sustained drug release behavior of the loading capsules was discovered via performing a release test in the PBS buffer (pH 7.4) solution at 310 k. Furthermore, SiO 2@CdSe/PPy could be converted to various smart hollow capsules via selectively removal of their relevant components.

  14. Surfactant-assisted dispersion of carbon nanotubes: mechanism of stabilization and biocompatibility of the surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Raman Preet, E-mail: ramanpreetsingh@hotmail.com [Evalueserve SEZ (Gurgaon) Pvt. Ltd. (India); Jain, Sanyog [National Institute of Pharmaceutical Education and Research, Centre for Pharmaceutical Nanotechnology, Department of Pharmaceutics (India); Ramarao, Poduri, E-mail: ramaraop@yahoo.com [Central University of Punjab, School of Basic and Applied Sciences (India)

    2013-10-15

    Nanoparticles (NPs) are thermodynamically unstable system and tend to aggregate to reduce free energy. The aggregation property of NPs results in inhomogeneous exposure of cells to NPs resulting in variable cellular responses. Several types of surfactants are used to stabilize NP dispersions and obtain homogenous dispersions. However, the effects of these surfactants, per se, on cellular responses are not completely known. The present study investigated the application of Pluronic F68 (PF68) for obtaining stable dispersion of NPs using carbon nanotubes as model NPs. PF68-stabilized NP suspensions are stable for long durations and do not show signs of aggregation or settling during storage or after autoclaving. The polyethylene oxide blocks in PF68 provide steric hindrance between adjacent NPs leading to stable NP dispersions. Further, PF68 is biocompatible in nature and does not affect integrity of mitochondria, lysosomes, DNA, and nuclei. Also, PF68 neither induce free radical or cytokine production nor does it interfere with cellular uptake mechanisms. The results of the present study suggest that PF68-assisted dispersion of NPs produced suspensions, which are stable after autoclaving. Further, PF68 does not interfere with normal physiological functions suggesting its application in nanomedicine and nanotoxicity evaluation.

  15. Surfactant-assisted dispersion of carbon nanotubes: mechanism of stabilization and biocompatibility of the surfactant

    International Nuclear Information System (INIS)

    Nanoparticles (NPs) are thermodynamically unstable system and tend to aggregate to reduce free energy. The aggregation property of NPs results in inhomogeneous exposure of cells to NPs resulting in variable cellular responses. Several types of surfactants are used to stabilize NP dispersions and obtain homogenous dispersions. However, the effects of these surfactants, per se, on cellular responses are not completely known. The present study investigated the application of Pluronic F68 (PF68) for obtaining stable dispersion of NPs using carbon nanotubes as model NPs. PF68-stabilized NP suspensions are stable for long durations and do not show signs of aggregation or settling during storage or after autoclaving. The polyethylene oxide blocks in PF68 provide steric hindrance between adjacent NPs leading to stable NP dispersions. Further, PF68 is biocompatible in nature and does not affect integrity of mitochondria, lysosomes, DNA, and nuclei. Also, PF68 neither induce free radical or cytokine production nor does it interfere with cellular uptake mechanisms. The results of the present study suggest that PF68-assisted dispersion of NPs produced suspensions, which are stable after autoclaving. Further, PF68 does not interfere with normal physiological functions suggesting its application in nanomedicine and nanotoxicity evaluation

  16. Design and Optical Trapping of a Biocompatible Propeller-like Nanoscale Hybrid

    Science.gov (United States)

    Do, Jaekwon; Schreiber, Robert; Lutich, Andrey A.; Liedl, Tim; Rodríguez-Fernández, Jessica; Feldmann, Jochen

    2013-01-01

    Designing nanoscale objects with the potential to perform externally-controlled motion in biological environments is one of the most sought-after objectives in nanotechnology. Different types of chemically and physically-powered motors have been prepared at the macro- and microscale. However, the preparation of nanoscale objects with a complex morphology, and the potential for light-driven motion has remained elusive to date. Here, we go a step forward by designing a nanoscale hybrid with a propeller-resembling shape, which can be controlled by focused light under biological conditions. Our hybrid, hereafter ‘Au@DNA-origami’, consists of a spherical gold nanoparticle with self-assembled, biocompatible, two-dimensional (2D) DNA sheets on its surface. As a first step towards the potential utilization of these nanoscale objects as light-driven assemblies in biological environments, we show that they can be optically trapped, and hence translated and deposited on-demand, and that under realistic trapping conditions the thermally-induced dehybridization of the DNA sheets can be avoided. PMID:22924473

  17. Composite nanoparticle of Au and quantum dots for X-ray computed tomography and fluorescence dual-mode imaging in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ji-Tao; Yang, Xiao-Quan; Zhang, Xiao-Shuai; Yan, Dong-Mei; Yao, Ming-Hao; Qin, Meng-Yao; Zhao, Yuan-Di, E-mail: zydi@mail.hust.edu.cn [Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology (China)

    2015-12-15

    In this study, composite nanoparticles comprising Au nanoparticle and quantum dots were built and used for contrast-enhanced computed tomography imaging (CT) and fluorescence dual-mode imaging in vivo. The nanoparticle exhibited good monodispersity and good biocompatibility, and had excellent CT contrast-enhancement effect and fluorescence imaging capability. They were appropriate for being used as dual-mode imaging probe in vivo.

  18. Composite nanoparticle of Au and quantum dots for X-ray computed tomography and fluorescence dual-mode imaging in vivo

    International Nuclear Information System (INIS)

    In this study, composite nanoparticles comprising Au nanoparticle and quantum dots were built and used for contrast-enhanced computed tomography imaging (CT) and fluorescence dual-mode imaging in vivo. The nanoparticle exhibited good monodispersity and good biocompatibility, and had excellent CT contrast-enhancement effect and fluorescence imaging capability. They were appropriate for being used as dual-mode imaging probe in vivo

  19. Synthesis of water soluble glycine capped silver nanoparticles and their surface selective interaction

    International Nuclear Information System (INIS)

    Highlights: • Synthesis of water soluble silver nanoparticles at ambient reaction conditions. • Glycine as stabilizing agent for silver nanoparticles. • Surface selective interaction of glycine with silver nanoparticles. • Glycine concentration influences crystalinity and optical property of silver nanoparticles. - Abstract: Synthesis of biocompatible metal nanoparticles has been an area of significant interest because of their wide range of applications. In the present study, we have successfully synthesized water soluble silver nanoparticles assisted by small amino acid glycine. The method is primarily based on reduction of AgNO3 with NaBH4 in aqueous solution under atmospheric air in the presence of glycine. UV–vis spectroscopy, transmission electron microscopy (TEM), X–ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG) and differential thermal analysis (DTA) techniques used for characterization of resulting silver nanoparticles demonstrated that, glycine is an effective capping agent to stabilize silver nanoparticles. Surface selective interaction of glycine on (1 1 1) face of silver nanoparticles has been investigated. The optical property and crystalline behavior of silver nanoparticles were found to be sensitive to concentration of glycine. X–ray diffraction studies ascertained the phase specific interaction of glycine on silver nanoparticles. Silver nanoparticles synthesized were of diameter 60 nm. We thus demonstrated an efficient synthetic method for synthesis of water soluble silver nanoparticles capped by amino acid under mild reaction conditions with excellent reproducibility

  20. Synthesis and characterization of α-NaYF4: Yb, Er nanoparticles by reverse microemulsion method

    Science.gov (United States)

    Gunaseelan, M.; Senthilselvan, J.

    2016-05-01

    A simple and cost effective reverse microemulsion system was newly designed to synthesis NaYF4:20%Yb,2%Er upconverting luminescent nanoparticles. XRD results confirms the cubic structure of NaYF4 nanophosphor in the as prepared condition without any other impurity phases. The as-prepared sample itself having highly crystalline nanoparticle with well dispersed uniform morphology is the advantage of this reverse microemulsion process. HRTEM images of as prepared and calcined samples revealed spherical nanoclusters morphology with size of ~210 nm and ~245 nm respectively. The characteristic absorption wavelength that occurs at 980 nm due to transition of energy levels 2F5/2 to 2F7/2 for Yb3+ rare earth ion in as prepared and calcined upconversion nanoparticle confirms the presence of Yb3+ by UV-Visible spectroscopy which can act as a sensitizer for photonic upconversion. Therefore the absorption at NIR region and emission spectrum at visible region suggests that NaYF4:20%Yb,2%Er is suitable for upcoversion process, due to its optical property and chemical stability this material also be useful for bio imaging applications.

  1. Parallel multifunctionalization of nanoparticles: a one-step modular approach for in vivo imaging.

    Science.gov (United States)

    Groult, Hugo; Ruiz-Cabello, Jesús; Pellico, Juan; Lechuga-Vieco, Ana V; Bhavesh, Riju; Zamai, Moreno; Almarza, Elena; Martín-Padura, Inés; Cantelar, Eugenio; Martínez-Alcázar, María P; Herranz, Fernando

    2015-01-21

    Multifunctional nanoparticles are usually produced by sequential synthesis, with long multistep protocols. Our study reports a generic modular strategy for the parallel one-step multifunctionalization of different hydrophobic nanoparticles. The method was designed and developed by taking advantage of the natural noncovalent interactions between the fatty acid binding sites of the bovine serum albumin (BSA) and the aliphatic surfactants on different inorganic nanomaterials. As a general example of the approach, three different nanoparticles-iron oxide, upconverting nanophosphors, and gold nanospheres-were nanoemulsified in water with BSA. To support specific applications, multifunctional capability was incorporated with a variety of previously modified BSA modules. These modules include different conjugated groups, such as chelating agents for (68)Ga or (89)Zr and ligand molecules for enhanced in vivo targeting. A large library of 13 multimodal contrast agents was developed with this convergent strategy. This platform allows a highly versatile and easy tailoring option for efficient incorporation of functional groups. Finally, as demonstration of this versatility, a bimodal (PET/MRI) probe including a maleimide-conjugated BSA was selectively synthesized with an RGD peptide for in vivo imaging detection of tumor angiogenesis.

  2. Selective killing of cancer cells by nanoparticle-assisted ultrasound

    OpenAIRE

    Kosheleva, Olga K.; Lai, Tsung-Ching; Chen, Nelson G.; Hsiao, Michael; Chen, Chung-Hsuan

    2016-01-01

    Background Intense ultrasound, such as that used for tumor ablation, does not differentiate between cancerous and normal cells. A method combining ultrasound and biocompatible gold or magnetic nanoparticles (NPs) was developed under in vitro conditions using human breast and lung epithelial cells, which causes ultrasound to preferentially destroy cancerous cells. Results Co-cultures of BEAS-2B normal lung cells and A549 cancerous lung cells labeled with green and red fluorescent proteins, res...

  3. Blocked-micropores, surface functionalized, bio-compatible and silica-coated iron oxide nanocomposites as advanced MRI contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Darbandi, Masih, E-mail: masih.darbandi@uni-due.de [Vanderbilt University, Department of Physics and Vanderbilt Institute of Nanoscale Science and Engineering (VINSE) (United States); Laurent, Sophie [University of Mons, Department of General, Organic and Biomedical Chemistry NMR and Molecular Imaging Laboratory (Belgium); Busch, Martin [University of Duisburg-Essen, Nanoparticle Process Technology, Faculty of Engineering and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Li Zian [University of Duisburg-Essen, Faculty of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Yuan Ying; Krueger, Michael [University of Freiburg, Department of Microsystems Engineering and Freiburg Materials Research Centre (Germany); Farle, Michael [University of Duisburg-Essen, Faculty of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Winterer, Markus [University of Duisburg-Essen, Nanoparticle Process Technology, Faculty of Engineering and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Vander Elst, Luce; Muller, Robert N. [University of Mons, Department of General, Organic and Biomedical Chemistry NMR and Molecular Imaging Laboratory (Belgium); Wende, Heiko [University of Duisburg-Essen, Faculty of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany)

    2013-05-15

    Biocompatible magnetic nanoparticles have been found promising in several biomedical applications for tagging, imaging, sensing and separation in recent years. In this article, a systematic study of the design and development of surface-modification schemes for silica-coated iron oxide nanoparticles (IONP) via a one-pot, in situ method at room temperature is presented. Silica-coated IONP were prepared in a water-in-oil microemulsion, and subsequently the surface was modified via addition of organosilane reagents to the microemulsion system. The structure and the morphology of the as synthesized nanoparticles have been investigated by means of transmission electron microscopy (TEM) and measurement of N{sub 2} adsorption-desorption. Electron diffraction and high-resolution transmission electron microscopic (TEM) images of the nanoparticles showed the highly crystalline nature of the IONP structures. Nitrogen adsorption indicates microporous and blocked-microporous structures for the silica-coated and amine functionalized silica-coated IONP, respectively which could prove less cytotoxicity of the functionalized final product. Besides, the colloidal stability of the final product and the presence of the modified functional groups on top of surface layer have been proven by zeta-potential measurements. Owing to the benefit from the inner IONP core and the hydrophilic silica shell, the as-synthesized nanocomposites were exploited as an MRI contrast enhancement agent. Relaxometric results prove that the surface functionalized IONP have also signal enhancement properties. These surface functionalized nanocomposites are not only potential candidates for highly efficient contrast agents for MRI, but could also be used as ultrasensitive biological-magnetic labels, because they are in nanoscale size, having magnetic properties, blocked-microporous and are well dispersible in biological environment.

  4. Preparation of ciprofloxacin-coated zinc oxide nanoparticles and their antibacterial effects against clinical isolates of Staphylococcus aureus and Escherichia coli

    DEFF Research Database (Denmark)

    Seif, Sepideh; Kazempour, Zarah Bahri; Pourmand, Mohammad Reza;

    2011-01-01

    carbonyl group in ciprofloxacin is actively involved in forming chemical - rather than physical - bonds with zinc oxide nanoparticles. Also the antibacterial activity of free zinc oxide nanoparticles and ciprofloxacin-coated zinc oxide nanoparticles have been evaluated against different clinical isolates...... pure ciprofloxacin) considerably enhanced the antibacterial activity of zinc oxide nanoparticles against different isolates of Staphylococcus aureus and Escherichia coli (4 to 32 fold increase). The result is of particular value, since it demonstrates that, by using biocompatible zinc oxide...... nanoparticles in combination therapy, lower amounts of antibiotics may be needed...

  5. Synthesis of Bio-Compatible SPION–based Aqueous Ferrofluids and Evaluation of RadioFrequency Power Loss for Magnetic Hyperthermia

    Directory of Open Access Journals (Sweden)

    Sakthikumar D

    2010-01-01

    Full Text Available Abstract Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc. This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.

  6. Venom conjugated polylactide applied as biocompatible material for passive and active immunotherapy against scorpion envenomation.

    Science.gov (United States)

    Ayari-Riabi, Sana; Trimaille, Thomas; Mabrouk, Kamel; Bertin, Denis; Gigmes, Didier; Benlasfar, Zakaria; Zaghmi, Ahlem; Bouhaouala-Zahar, Balkiss; Elayeb, Mohamed

    2016-04-01

    Scorpion envenoming represents a public health issue in subtropical regions of the world. Treatment and prevention need to promote antitoxin immunity. Preserving antigenic presentation while removing toxin effect remains a major challenge in toxin vaccine development. Among particulate adjuvant, particles prepared with poly (D,L-lactide) polymer are the most extensively investigated due to their excellent biocompatibility and biodegradability. The aim of this study is to develop surfactant-free PLA nanoparticles that safely deliver venom toxic fraction to enhance specific immune response. PLA nanoparticles are coated with AahG50 (AahG50/PLA) and BotG50 (BotG50/PLA): a toxic fraction purified from Androctonus australis hector and Buthus occitanus tunetanus venoms, respectively. Residual toxicities are evaluated following injections of PLA-containing high doses of AahG50 (or BotG50). Immunization trials are performed with the detoxified fraction administered alone without adjuvant. A comparative study of the effect of Freund is also included. The neutralizing capacity of sera is determined in naive mice. Six months later, immunized mice are challenged subcutaneously with increased doses of AahG50. Subcutaneous lethal dose 50 (LD50) of AahG50 and BotG50 is of 575 μg/kg and 1300 μg/kg respectively. By comparison, BotG50/PLA is totally innocuous while 50% of tested mice survive 2875 μg AahG50/kg. Alhydrogel and Freund are not able to detoxify such a high dose. Cross-antigenicity between particulate and soluble fraction is also, ensured. AahG50/PLA and BotG50/PLA induce high antibody levels in mice serum. The neutralizing capacity per mL of anti-venom was 258 μg/mL and 186 μg/mL calculated for anti-AahG50/PLA and anti-BotG50/PLA sera, respectively. Animals immunized with AahG50/PLA are protected against AahG50 injected dose of 3162 μg/kg as opposed all non-immunized mice died at this dose. We find that the detoxification approach based PLA nanoparticles, benefit

  7. Synthesis of biocompatible polymers by plasma; Sintesis de polimeros biocompatibles por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Colin O, E

    2007-07-01

    In this work biocompatible polymers were synthesized by plasma based on pyrrole, ethyleneglycol and allylamine. These monomers are biologically important because they contain oxygen and nitrogen in their structure and they form bonding like; N-H, C-N, C-O and O-H that are also in the human system. The polymers were synthesized with splendor electric discharges to 13.5 MHz, among 10 and 100 W, resistive coupling, pressure of 10{sup -1} mbar and 180 minutes of reaction. The interaction of the biological systems with biomaterials depends in many cases of the properties that present the surfaces, because the rough and/or porous surfaces favor the adherence of cells. The results indicate that the ruggedness of the polymers can be controlled with the synthesis energy, since when modifying it flat and/or rough surfaces they are obtained. The compatibility of water with other solutions that it is a form of increasing the adhesion of cells with biopolymers. The affinity with water and solutions is evaluated calculating the contact angle of the polymers surface with drops of concentration solutions and similar composition to the extracellular liquid of the spinal marrow of the human body. The solutions that were proven were based on NaCl, NaCl-MgSO{sub 4}, and a mixture Krebs-Ringer that has chemical composition and similar concentration to that of the fluids of the spinal marrow. In the Poly pyrrole (PPy)/Polyethyleneglycol (PEG) copolymer, the biggest angles corresponded to the Krebs-Ringer solution, in the interval of 18 to 14 degrees and those lowest to the NaCl solution, of 14.5 at 11 degrees. The Poly allylamine had the more high values with water in the interval of 16.5 to 12.5 degrees and those lowest with the NaCl solution, of 13 at 9.5 degrees. On the other hand, in the derived polymers of pyrrole the more high values corresponded to the treatment with water, until 37, and those lowest to the NaCl-MgSO{sub 4} solution, up to 10. The solutions where participated Na

  8. Synthesis of biocompatible polymers by plasma; Sintesis de polimeros biocompatibles por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Colin O, E

    2007-07-01

    In this work biocompatible polymers were synthesized by plasma based on pyrrole, ethyleneglycol and allylamine. These monomers are biologically important because they contain oxygen and nitrogen in their structure and they form bonding like; N-H, C-N, C-O and O-H that are also in the human system. The polymers were synthesized with splendor electric discharges to 13.5 MHz, among 10 and 100 W, resistive coupling, pressure of 10{sup -1} mbar and 180 minutes of reaction. The interaction of the biological systems with biomaterials depends in many cases of the properties that present the surfaces, because the rough and/or porous surfaces favor the adherence of cells. The results indicate that the ruggedness of the polymers can be controlled with the synthesis energy, since when modifying it flat and/or rough surfaces they are obtained. The compatibility of water with other solutions that it is a form of increasing the adhesion of cells with biopolymers. The affinity with water and solutions is evaluated calculating the contact angle of the polymers surface with drops of concentration solutions and similar composition to the extracellular liquid of the spinal marrow of the human body. The solutions that were proven were based on NaCl, NaCl-MgSO{sub 4}, and a mixture Krebs-Ringer that has chemical composition and similar concentration to that of the fluids of the spinal marrow. In the Poly pyrrole (PPy)/Polyethyleneglycol (PEG) copolymer, the biggest angles corresponded to the Krebs-Ringer solution, in the interval of 18 to 14 degrees and those lowest to the NaCl solution, of 14.5 at 11 degrees. The Poly allylamine had the more high values with water in the interval of 16.5 to 12.5 degrees and those lowest with the NaCl solution, of 13 at 9.5 degrees. On the other hand, in the derived polymers of pyrrole the more high values corresponded to the treatment with water, until 37, and those lowest to the NaCl-MgSO{sub 4} solution, up to 10. The solutions where participated Na

  9. Magnetic nanoparticles for application in cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, J. [Department of Applied Physics, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Banobre-Lopez, M. [Department of Physical Chemistry, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Pineiro-Redondo, Y. [Department of Applied Physics, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Rivas, B., E-mail: jose.rivas@usc.es [Department of Operative Dentistry and Endodontics, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Lopez-Quintela, M.A. [Department of Physical Chemistry, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain)

    2012-10-15

    Magnetic particles play nowadays an important role in different technological areas with potential applications in fields such as electronics, energy and biomedicine. In this report we will focus on the hyperthermia properties of magnetite nanoparticles and the effect of several chemical/physical parameters on their heating properties. We will discuss about the need of searching new smaller magnetic systems in order to fulfill the required physical properties which allow treating tumoral tissues more efficiently by means of magnetically induced heat. Preliminary results will be shown about the effect of a biocompatible shell of core-shell magnetite NPs on the heating properties by application of a RF magnetic field.

  10. Magnetic nanoparticles for application in cancer therapy

    International Nuclear Information System (INIS)

    Magnetic particles play nowadays an important role in different technological areas with potential applications in fields such as electronics, energy and biomedicine. In this report we will focus on the hyperthermia properties of magnetite nanoparticles and the effect of several chemical/physical parameters on their heating properties. We will discuss about the need of searching new smaller magnetic systems in order to fulfill the required physical properties which allow treating tumoral tissues more efficiently by means of magnetically induced heat. Preliminary results will be shown about the effect of a biocompatible shell of core–shell magnetite NPs on the heating properties by application of a RF magnetic field.

  11. A Proteomic View to Characterize the Effect of Chitosan Nanoparticle to Hepatic Cells: Is Chitosan Nanoparticle an Enhancer of PI3K/AKT1/mTOR Pathway?

    OpenAIRE

    Ming-Hui Yang; Shyng-Shiou Yuan; Ying-Fong Huang; Po-Chiao Lin; Chi-Yu Lu; Tze-Wen Chung; Yu-Chang Tyan

    2014-01-01

    Chitosan nanoparticle, a biocompatible material, was used as a potential drug delivery system widely. Our current investigation studies were the bioeffects of the chitosan nanoparticle uptake by liver cells. In this experiment, the characterizations of chitosan nanoparticles were measured by transmission electron microscopy and particle size analyzer. The average size of the chitosan nanoparticle was 224.6 ± 11.2 nm, and the average zeta potential was +14.08 ± 0.7 mV. Moreover, using proteomi...

  12. Green chemistry approach for the synthesis of biocompatible graphene

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, Jae Woong; Kim, Jin-Hoi

    2013-01-01

    Background Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms isolated from its three-dimensional parent material, graphite. One of the most common methods for preparation of graphene is chemical exfoliation of graphite using powerful oxidizing agents. Generally, graphene is synthesized through deoxygenation of graphene oxide (GO) by using hydrazine, which is one of the most widespread and strongest reducing agents. Due to the high toxicity of hydrazine, it is not a promising reducing agent in large-scale production of graphene; therefore, this study focused on a green or sustainable synthesis of graphene and the biocompatibility of graphene in primary mouse embryonic fibroblast cells (PMEFs). Methods Here, we demonstrated a simple, rapid, and green chemistry approach for the synthesis of reduced GO (rGO) from GO using triethylamine (TEA) as a reducing agent and stabilizing agent. The obtained TEA reduced GO (TEA-rGO) was characterized by ultraviolet (UV)–visible absorption spectroscopy, X-ray diffraction (XRD), particle size dynamic light scattering (DLS), scanning electron microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM). Results The transition of graphene oxide to graphene was confirmed by UV–visible spectroscopy. XRD and SEM were used to investigate the crystallinity of graphene and the surface morphologies of prepared graphene respectively. The formation of defects further supports the functionalization of graphene as indicated in the Raman spectrum of TEA-rGO. Surface morphology and the thickness of the GO and TEA-rGO were analyzed using AFM. The presented results suggest that TEA-rGO shows significantly more biocompatibility with PMEFs cells than GO. Conclusion This is the first report about using TEA as a reducing as well as a stabilizing agent for the preparation of biocompatible graphene. The proposed safe and green method offers substitute routes for large-scale production of graphene

  13. Aqueous ferrofluid of magnetite nanoparticles: Fluorescence labeling and magnetophoretic control.

    Science.gov (United States)

    Sahoo, Yudhisthira; Goodarzi, Alireza; Swihart, Mark T; Ohulchanskyy, Tymish Y; Kaur, Navjot; Furlani, Edward P; Prasad, Paras N

    2005-03-10

    A method is presented for the preparation of a biocompatible ferrofluid containing dye-functionalized magnetite nanoparticles that can serve as fluorescent markers. This method entails the surface functionalization of magnetite nanoparticles using citric acid to produce a stable aqueous dispersion and the subsequent binding of fluorescent dyes to the surface of the particles. Several ferrofluid samples were prepared and characterized using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), BET surface area analysis, transmission electron microscopy (TEM), and SQUID magnetometry. In addition, confocal fluorescence microscopy was used to study the response of the fluorescent nanoparticles to an applied magnetic field and their uptake by cells in vitro. Results are presented on the distribution of particle sizes, the fluorescent and magnetic properties of the nanoparticles, and the nature of their surface bonds. Biocompatible ferrofluids with fluorescent nanoparticles enable optical tracking of basic processes at the cellular level combined with magnetophoretic manipulation and should be of substantial value to researchers engaged in both fundamental and applied biomedical research. PMID:16851439

  14. Biocompatible implants and methods of making and attaching the same

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, Adrian P; Laude, Lucien D; Humayun, Mark S; Weiland, James D; Lotfi, Atoosa; Markland, Jr., Francis S

    2014-10-07

    The invention provides a biocompatible silicone implant that can be securely affixed to living tissue through interaction with integral membrane proteins (integrins). A silicone article containing a laser-activated surface is utilized to make the implant. One example is an implantable prosthesis to treat blindness caused by outer retinal degenerative diseases. The device bypasses damaged photoreceptors and electrically stimulates the undamaged neurons of the retina. Electrical stimulation is achieved using a silicone microelectrode array (MEA). A safe, protein adhesive is used in attaching the MEA to the retinal surface and assist in alleviating focal pressure effects. Methods of making and attaching such implants are also provided.

  15. A biocompatible alkene hydrogenation merges organic synthesis with microbial metabolism.

    Science.gov (United States)

    Sirasani, Gopal; Tong, Liuchuan; Balskus, Emily P

    2014-07-21

    Organic chemists and metabolic engineers use orthogonal technologies to construct essential small molecules such as pharmaceuticals and commodity chemicals. While chemists have leveraged the unique capabilities of biological catalysts for small-molecule production, metabolic engineers have not likewise integrated reactions from organic synthesis with the metabolism of living organisms. Reported herein is a method for alkene hydrogenation which utilizes a palladium catalyst and hydrogen gas generated directly by a living microorganism. This biocompatible transformation, which requires both catalyst and microbe, and can be used on a preparative scale, represents a new strategy for chemical synthesis that combines organic chemistry and metabolic engineering.

  16. Biodegradable Xylitol-Based Elastomers: In Vivo Behavior and Biocompatibility

    Science.gov (United States)

    Bruggeman, Joost P.; Bettinger, Christopher J.; Langer, Robert

    2010-01-01

    Biodegradable elastomers based on polycondensation reactions of xylitol with sebacic acid, referred to as poly(xylitol sebacate) (PXS) elastomers have recently been developed. Herein, we describe the in vivo behavior of PXS elastomers. Four PXS elastomers were synthesized, characterized and compared to poly(L-lactic-co-glycolic acid) (PLGA). PXS elastomers displayed a high level of structural integrity and form stability during degradation. The in vivo half-life ranged from approximately 3 to 52 weeks. PXS elastomers exhibited increased biocompatibility compared to PLGA implants. PMID:20540093

  17. Mechanical biocompatibilities of titanium alloys for biomedical applications.

    Science.gov (United States)

    Niinomi, Mitsuo

    2008-01-01

    Young's modulus as well as tensile strength, ductility, fatigue life, fretting fatigue life, wear properties, functionalities, etc., should be adjusted to levels that are suitable for structural biomaterials used in implants that replace hard tissue. These factors may be collectively referred to as mechanical biocompatibilities. In this paper, the following are described with regard to biomedical applications of titanium alloys: the Young's modulus, wear properties, notch fatigue strength, fatigue behaviour on relation to ageing treatment, improvement of fatigue strength, fatigue crack propagation resistance and ductility by the deformation-induced martensitic transformation of the unstable beta phase, and multifunctional deformation behaviours of titanium alloys.

  18. Biocompatibility and applications of carbon nanotubes in medical nanorobots.

    Science.gov (United States)

    Popov, Andrei M; Lozovik, Yurii E; Fiorito, Silvana; Yahia, L'Hocine

    2007-01-01

    The set of nanoelectromechanical systems (NEMS) based on relative motion of carbon nanotubes walls is proposed for use in medical nanorobots. This set includes electromechanical nanothermometer, jet nanoengine, nanosyringe (the last can be used simultaneously as nanoprobe for individual biological molecules and drug nanodeliver). Principal schemes of these NEMS are considered. Operational characteristics of nanothermometer are analyzed. The possible methods of these NEMS actuation are considered. The present-day progress in nanotechnology techniques which are necessary for assembling of NEMS under consideration is discussed. Biocompatibility of carbon nanotubes is analyzed in connection with perspectives of their application in nanomedicine.

  19. 3D structuring of biocompatible and biodegradable polymers via stereolithography.

    Science.gov (United States)

    Gill, Andrew A; Claeyssens, Frederik

    2011-01-01

    The production of user-defined 3D microstructures from biocompatible and biodegradable materials via free-form fabrication is an important step to create off-the-shelf technologies to be used as tissue engineering scaffolds. One method of achieving this is the microstereolithography of block copolymers, allowing high resolution microstructuring of materials with tuneable physical properties. A versatile protocol for the production and photofunctionalisation of pre-polymers for microstereolithography is presented along with a discussion of the possible microstereolithography set-ups and previous work in the field.

  20. Genotoxicity of Superparamagnetic Iron Oxide Nanoparticles in Granulosa Cells

    Directory of Open Access Journals (Sweden)

    Marina Pöttler

    2015-11-01

    Full Text Available Nanoparticles that are aimed at targeting cancer cells, but sparing healthy tissue provide an attractive platform of implementation for hyperthermia or as carriers of chemotherapeutics. According to the literature, diverse effects of nanoparticles relating to mammalian reproductive tissue are described. To address the impact of nanoparticles on cyto- and genotoxicity concerning the reproductive system, we examined the effect of superparamagnetic iron oxide nanoparticles (SPIONs on granulosa cells, which are very important for ovarian function and female fertility. Human granulosa cells (HLG-5 were treated with SPIONs, either coated with lauric acid (SEONLA only, or additionally with a protein corona of bovine serum albumin (BSA; SEONLA-BSA, or with dextran (SEONDEX. Both micronuclei testing and the detection of γH2A.X revealed no genotoxic effects of SEONLA-BSA, SEONDEX or SEONLA. Thus, it was demonstrated that different coatings of SPIONs improve biocompatibility, especially in terms of genotoxicity towards cells of the reproductive system.

  1. Nanoparticles, lung injury, and the role of oxidant stress.

    Science.gov (United States)

    Madl, Amy K; Plummer, Laurel E; Carosino, Christopher; Pinkerton, Kent E

    2014-01-01

    The emergence of engineered nanoscale materials has provided significant advancements in electronic, biomedical, and material science applications. Both engineered nanoparticles and nanoparticles derived from combustion or incidental processes exhibit a range of physical and chemical properties that induce inflammation and oxidative stress in biological systems. Oxidative stress reflects the imbalance between the generation of reactive oxygen species and the biochemical mechanisms to detoxify and repair the damage resulting from reactive intermediates. This review examines current research on incidental and engineered nanoparticles in terms of their health effects on lungs and the mechanisms by which oxidative stress via physicochemical characteristics influences toxicity or biocompatibility. Although oxidative stress has generally been thought of as an adverse biological outcome, this review also briefly discusses some of the potential emerging technologies to use nanoparticle-induced oxidative stress to treat disease in a site-specific fashion. PMID:24215442

  2. Enhanced oxidation of nanoparticles through strain-mediated ionic transport

    Science.gov (United States)

    Pratt, Andrew; Lari, Leonardo; Hovorka, Ondrej; Shah, Amish; Woffinden, Charles; Tear, Steve P.; Binns, Chris; Kröger, Roland

    2014-01-01

    Geometry and confinement effects at the nanoscale can result in substantial modifications to a material’s properties with significant consequences in terms of chemical reactivity, biocompatibility and toxicity. Although benefiting applications across a diverse array of environmental and technological settings, the long-term effects of these changes, for example in the reaction of metallic nanoparticles under atmospheric conditions, are not well understood. Here, we use the unprecedented resolution attainable with aberration-corrected scanning transmission electron microscopy to study the oxidation of cuboid Fe nanoparticles. Performing strain analysis at the atomic level, we reveal that strain gradients induced in the confined oxide shell by the nanoparticle geometry enhance the transport of diffusing species, ultimately driving oxide domain formation and the shape evolution of the particle. We conjecture that such a strain-gradient-enhanced mass transport mechanism may prove essential for understanding the reaction of nanoparticles with gases in general, and for providing deeper insight into ionic conductivity in strained nanostructures.

  3. Green synthesis, characterization of gold and silver nanoparticles and their potential application for cancer therapeutics

    Energy Technology Data Exchange (ETDEWEB)

    Patra, Sujata; Mukherjee, Sudip; Barui, Ayan Kumar; Ganguly, Anirban [Biomaterials Group, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, Telangana State (India); Sreedhar, Bojja [Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, Telangana State (India); Patra, Chitta Ranjan, E-mail: crpatra@iict.res.in [Biomaterials Group, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, Telangana State (India)

    2015-08-01

    In the present article, we demonstrate the delivery of anti-cancer drug to the cancer cells using biosynthesized gold and silver nanoparticles (b-AuNP & b-AgNP). The nanoparticles synthesized by using Butea monosperma (BM) leaf extract are thoroughly characterized by various analytical techniques. Both b-AuNP and b-AgNP are stable in biological buffers and biocompatible towards normal endothelial cells (HUVEC, ECV-304) as well as cancer cell lines (B16F10, MCF-7, HNGC2 & A549). Administration of nanoparticle based drug delivery systems (DDSs) using doxorubicin (DOX) [b-Au-500-DOX and b-Ag-750-DOX] shows significant inhibition of cancer cell proliferation (B16F10, MCF-7) compared to pristine drug. Therefore, we strongly believe that biosynthesized nanoparticles will be useful for the development of cancer therapy using nanomedicine approach in near future. - Highlights: • Biosynthesis of gold and silver nanoparticles using plant leaf extract • The approach is clean, efficient, eco-friendly & economically safe. • Biosynthesized nanoparticles are biocompatible towards normal and cancer cells. • Design and development of biosynthesized nanoparticle based drug delivery systems • Biosynthesized nanoparticles could be useful for cancer and other diseases.

  4. Surface engineering of silica nanoparticles for oral insulin delivery: characterization and cell toxicity studies.

    Science.gov (United States)

    Andreani, Tatiana; Kiill, Charlene P; de Souza, Ana Luiza R; Fangueiro, Joana F; Fernandes, Lisete; Doktorovová, Slavomira; Santos, Dario L; Garcia, Maria L; Gremião, Maria Palmira D; Souto, Eliana B; Silva, Amélia M

    2014-11-01

    The present work aimed at studying the interaction between insulin and SiNP surfaced with mucoadhesive polymers (chitosan, sodium alginate or polyethylene glycol) and the evaluation of their biocompatibility with HepG2 and Caco-2 cell lines, which mimic in vivo the target of insulin-loaded nanoparticles upon oral administration. Thus, a systematic physicochemical study of the surface-modified insulin-silica nanoparticles (Ins-SiNP) using mucoadhesive polymers has been described. The surfacing of nanoparticle involved the coating of silica nanoparticles (SiNP) with different mucoadhesive polymers, to achieve high contact between the systems and the gut mucosa to enhance the oral insulin bioavailability. SiNP were prepared by a modified Stöber method at room temperature via hydrolysis and condensation of tetraethyl orthosilicate (TEOS). Interaction between insulin and nanoparticles was assessed by differential scanning calorimetry (DSC), X-ray and Fourier-transform infrared (FTIR) studies. The high efficiency of nanoparticles' coating resulted in more stable system. FTIR spectra of insulin-loaded nanoparticles showed amide absorption bands which are characteristic of α-helix content. In general, all developed nanoparticles demonstrated high biocompatible, at the tested concentrations (50-500 μg/mL), revealing no or low toxicity in the two human cancer cell lines (HepG2 and Caco-2). In conclusion, the developed insulin-loaded SiNP surfaced with mucoadhesive polymers demonstrated its added value for oral administration of proteins. PMID:25466464

  5. Lung toxicities of core–shell nanoparticles composed of carbon, cobalt, and silica

    Directory of Open Access Journals (Sweden)

    Al Samri MT

    2013-03-01

    Full Text Available Mohammed T Al Samri,1,* Rafael Silva,2,* Saeeda Almarzooqi,3 Alia Albawardi,3 Aws Rashad Diab Othman,1 Ruqayya SMS Al Hanjeri,1 Shaikha KM Al Dawaar,1 Saeed Tariq,4 Abdul-Kader Souid,1 Tewodros Asefa2,51Department of Pediatrics, United Arab Emirates University, Abu Dhabi, United Arab Emirates; 2Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA; 3Department of Pathology, 4Department of Anatomy, United Arab Emirates University, Abu Dhabi, United Arab Emirates; 5Department of Chemical Engineering and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA*These authors contributed equally to this workAbstract: We present here comparative assessments of murine lung toxicity (biocompatibility after in vitro and in vivo exposures to carbon (C–SiO2-etched, carbon–silica (C–SiO2, carbon–cobalt–silica (C–Co–SiO2, and carbon–cobalt oxide–silica (C–Co3O4–SiO2 nanoparticles. These nanoparticles have potential applications in clinical medicine and bioimaging, and thus their possible adverse events require thorough investigation. The primary aim of this work was to explore whether the nanoparticles are biocompatible with pneumatocyte bioenergetics (cellular respiration and adenosine triphosphate content. Other objectives included assessments of caspase activity, lung structure, and cellular organelles. Pneumatocyte bioenergetics of murine lung remained preserved after treatment with C–SiO2-etched or C–SiO2 nanoparticles. C–SiO2-etched nanoparticles, however, increased caspase activity and altered lung structure more than C–SiO2 did. Consistent with the known mitochondrial toxicity of cobalt, both C–Co–SiO2 and C–Co3O4–SiO2 impaired lung tissue bioenergetics. C–Co–SiO2, however, increased caspase activity and altered lung structure more than C–Co3O4–SiO2. The results indicate that silica shell is essential for

  6. Estimation of Biocompatibility of Nano-Sized Ceramic Particles with Osteoblasts, Osteosarcomas and Hepatocytes by Static and Time-Lapse Observation.

    Science.gov (United States)

    Abe, Shigeaki; Seitoku, Eri; Iwadera, Nobuki; Hamba, Yusuke; Yamagata, Shuichi; Akasaka, Tsukasa; Kusaka, Teruo; Inoue, Satoshi; Yawaka, Yasutaka; Iida, Junichiro; Sano, Hidehiko; Yonezawa, Tetsu; Yoshida, Yasuhiro

    2016-03-01

    We assessed the biocompatibility of nano-sized ceramic particles with several cells types. Though these particles have less than 100 nm in diameter, they act as submicron-sized particles in saline by aggregation that was estimated using laser diffraction particle size analysis (LDS). they act as submicro-sized particles in saline by aggregation based on laser diffraction particle size analysis (LDS). Several types of cells (osteoblasts, osteosarcoma and hepatocyte cells) were exposed to these particles and their cytocompatibility was estimated. Not only the cytotoxic assay but also their static and dynamic morphology under nanoparticles exposure were investigated. The intercellular uptake of particles was determined using a confocal fluorescence microscope. The particles used in this study did not inhibit cellular activity or growth even when their concentrations were high. Only copper oxide particles caused acute cytotoxicity depending on the particle size. The cytotoxicity assay, dynamic behavior of the nanoparticle-exposed cells and their examination under a confocal fluorescence microscope suggests that the irritative reaction was induced by contact between the cells and particles, whereas eluted copper ions are not dominant factor. These results indicate that nano-sized particles used in this study have excellent biocompatibility except copper oxide ones.

  7. Biocompatible post-polymerization functionalization of a water soluble poly(p-phenylene ethynylene)

    OpenAIRE

    Swager, Timothy Manning; Vanveller, Brett Steven

    2010-01-01

    A biocompatible post-polymerization functionalization reaction takes advantage of a polymer's structural motif for the controllable attachment of biotin as a model biosensor that responds to streptavidin.

  8. Enhanced solubility and functionality of valrubicin (AD-32) against cancer cells upon encapsulation into biocompatible nanoparticles

    OpenAIRE

    Sabnis N, Nair M; Israel M; McConathy WJ; Lacko AG

    2012-01-01

    Nirupama Sabnis1, Maya Nair1, Mervyn Israel2, Walter J McConathy3, Andras G Lacko11University of North Texas Health Science Center, Fort Worth, TX, 2University of Tennessee Health Science Center, Memphis, TN, 3Texas Tech University Health Sciences Center–Permian Basin, Odessa, TX, USAAbstract: Among numerous drug-delivery approaches, reconstituted high-density lipoprotein (rHDL) nanocarriers have proven particularly applicable for delivering highly hydrophobic drugs. In this study, ...

  9. Biocompatibility of magnetic Fe3O4 nanoparticles and their cytotoxic effect on MCF-7 cells

    OpenAIRE

    Chen DZ; Tang QS; Li XD; Zhou XJ; Zang J; Xue WQ; Xiang JY; Guo CQ

    2012-01-01

    Daozhen Chen,1,3,* Qiusha Tang,2,* Xiangdong Li,3,* Xiaojin Zhou,1 Jia Zang,1 Wen-qun Xue,1 Jing-ying Xiang,1 Cai-qin Guo11Central Laboratory, Wuxi Hospital for Matemaland Child Health Care Affiliated Medical School of Nanjing, Jiangsu Province; 2Department of Pathology and Pathophysiology, Medical College, Southeast University, Jiangsu Province; 3The People’s Hospital of Aheqi County, Xinjiang, China *These authors contributed equally to this workBackground: The objective ...

  10. Toxicity and biocompatibility of nanoparticles, and studies on oxidative stress and DNA damage

    OpenAIRE

    Rodhe, Ylva

    2015-01-01

    Oxidative stress is associated with several diseases, either as a cause or a consequence. Chronic kidney disease (CKD) is one example of a disease in which elevated levels of oxidative stress are frequently reported. Oxidative stress, inflammation and malnutrition are risk factors that contribute to an increased risk for cardiovascular disease and a higher morbidity and mortality in CKD patients. In addition, oral complaints such as periodontitis and mouth dryness are recurrent...

  11. Structure of Biocompatible Coatings Produced from Hydroxyapatite Nanoparticles by Detonation Spraying.

    Science.gov (United States)

    Nosenko, Valentyna; Strutynska, Nataliia; Vorona, Igor; Zatovsky, Igor; Dzhagan, Volodymyr; Lemishko, Sergiy; Epple, Matthias; Prymak, Oleg; Baran, Nikolai; Ishchenko, Stanislav; Slobodyanik, Nikolai; Prylutskyy, Yuriy; Klyui, Nickolai; Temchenko, Volodymyr

    2015-12-01

    Detonation-produced hydroxyapatite coatings were studied by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Raman spectroscopy, and electron paramagnetic resonance (EPR) spectroscopy. The source material for detonation spraying was a B-type carbonated hydroxyapatite powder. The coatings consisted of tetracalcium phosphate and apatite. The ratio depended slightly on the degree of crystallinity of the initial powder and processing parameters of the coating preparation. The tetracalcium phosphate phase was homogeneous; the apatite phase contained defects localized on the sixfold axis and consisted of hydroxyapatite and oxyapatite. Technological factors contributing to the transformation of hydroxyapatite powder structure during coating formation by detonation spraying are discussed. PMID:26625888

  12. Chitosan–tripolyphosphate nanoparticles as Arrabidaea chica standardized extract carrier: synthesis, characterization, biocompatibility, and antiulcerogenic activity

    OpenAIRE

    Servat-Medina, Leila; González-Gómez, Alvaro; Reyes-Ortega, Felisa; Sousa, Ilza Maria Oliveira; de Cássia Almeida Queiroz, Nubia; Zago, Patricia Maria Wiziack; Jorge, Michelle Pedrosa; Monteiro, Karin Maia; de Carvalho, João Ernesto; Román, Julio San; Foglio, Mary Ann

    2015-01-01

    Natural products using plants have received considerable attention because of their potential to treat various diseases. Arrabidaea chica (Humb. & Bonpl.) B. Verlot is a native tropical American vine with healing properties employed in folk medicine for wound healing, inflammation, and gastrointestinal colic. Applying nanotechnology to plant extracts has revealed an advantageous strategy for herbal drugs considering the numerous features that nanostructured systems offer, including solubility...

  13. Biocompatibility of chitosan-coated iron oxide nanoparticles with osteoblast cells

    OpenAIRE

    Shi S.; Jia J; Guo X; Zhao Y; Chen D; Guo Y; Cheng T.; Zhang X

    2012-01-01

    Si-Feng Shi,1 Jing-Fu Jia,2 Xiao-Kui Guo,3 Ya-Ping Zhao,2 De-Sheng Chen,1 Yong-Yuan Guo,1 Tao Cheng,1 Xian-Long Zhang11Department of Orthopedic Surgery, Shanghai Sixth People’s Hospital, School of Medicine, 2School of Chemistry and Chemical Technology, 3Department of Medical Microbiology and Parasitology, School of Medicine, Shanghai Jiao Tong University Shanghai, ChinaBackground: Bone disorders (including osteoporosis, loosening of a prosthesis, and bone infections) are of great co...

  14. Fluorescent nanoparticles for intracellular sensing: A review

    Energy Technology Data Exchange (ETDEWEB)

    Ruedas-Rama, Maria J., E-mail: mjruedas@ugr.esmailto [Department of Physical Chemistry, Faculty of Pharmacy, University of Granada, Campus Cartuja, 18071, Granada (Spain); Walters, Jamie D. [Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, UK CB2 1QT (United Kingdom); Orte, Angel [Department of Physical Chemistry, Faculty of Pharmacy, University of Granada, Campus Cartuja, 18071, Granada (Spain); Hall, Elizabeth A.H., E-mail: lisa.hall@biotech.cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QT (United Kingdom)

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer Analytical applications of fluorescent nanoparticles (NPs) in intracellular sensing. Black-Right-Pointing-Pointer Critical review on performance of QDots, metal NPs, silica NPs, and polymer NPs. Black-Right-Pointing-Pointer Highlighted potential of fluorescence lifetime imaging microscopy (FLIM). - Abstract: Fluorescent nanoparticles (NPs), including semiconductor NPs (Quantum Dots), metal NPs, silica NPs, polymer NPs, etc., have been a major focus of research and development during the past decade. The fluorescent nanoparticles show unique chemical and optical properties, such as brighter fluorescence, higher photostability and higher biocompatibility, compared to classical fluorescent organic dyes. Moreover, the nanoparticles can also act as multivalent scaffolds for the realization of supramolecular assemblies, since their high surface to volume ratio allow distinct spatial domains to be functionalized, which can provide a versatile synthetic platform for the implementation of different sensing schemes. Their excellent properties make them one of the most useful tools that chemistry has supplied to biomedical research, enabling the intracellular monitoring of many different species for medical and biological purposes. In this review, we focus on the developments and analytical applications of fluorescent nanoparticles in chemical and biological sensing within the intracellular environment. The review also points out the great potential of fluorescent NPs for fluorescence lifetime imaging microscopy (FLIM). Finally, we also give an overview of the current methods for delivering of fluorescent NPs into cells, where critically examine the benefits and liabilities of each strategy.

  15. Shape memory alloys: metallurgy, biocompatibility, and biomechanics for neurosurgical applications.

    Science.gov (United States)

    Hoh, Daniel J; Hoh, Brian L; Amar, Arun P; Wang, Michael Y

    2009-05-01

    SHAPE MEMORY ALLOYS possess distinct dynamic properties with particular applications in neurosurgery. Because of their unique physical characteristics, these materials are finding increasing application where resiliency, conformation, and actuation are needed. Nitinol, the most frequently manufactured shape memory alloy, responds to thermal and mechanical stimuli with remarkable mechanical properties such as shape memory effect, super-elasticity, and high damping capacity. Nitinol has found particular use in the biomedical community because of its excellent fatigue resistance and biocompatibility, with special interest in neurosurgical applications. The properties of nitinol and its diffusionless phase transformations contribute to these unique mechanical capabilities. The features of nitinol, particularly its shape memory effect, super-elasticity, damping capacity, as well as its biocompatibility and biomechanics are discussed herein. Current and future applications of nitinol and other shape memory alloys in endovascular, spinal, and minimally invasive neurosurgery are introduced. An understanding of the metallurgic properties of nitinol provides a foundation for further exploration of its use in neurosurgical implant design.

  16. Preparation of biocompatible structural gradient coatings on pure titanium

    Institute of Scientific and Technical Information of China (English)

    TANG Guang-xin; ZHANG Ren-ji; YAN Yong-nian

    2004-01-01

    In order to overcome the poor osteo-inductive properties of titanium implant, some methods have been used. The efforts to improve implant biocompatibility and durability by applying a hybrid technique of composite oxidation (pre-anodic and micro-arc oxidation) and hydrothermal treatment were described. Pure titanium was used as the substrate material. An oxalic acid was used as the electrolyte for the pre-anodic oxidation. A calcium and phosphate salt solution was acted as the electrolyte of micro-arc oxidation and the common pure water was used for hydrothermal treatment. X-ray diffraction (XRD), and scanning electron microscopy (SEM) have been used to investigate the microstructure and morphology of the coatings. The results show that a compact TiO2 film can be made by pre-anodic oxidation, which is effective as chemical barriers against the in-vivo release of metal ions from the implants. A porous TiO2 coating can be produced by micro-arc oxidation on titanium plate, which is beneficial to bone tissue growth and enhancing anchorage of implant to bone. De-calcium HA can be formed on the coating using hydrothermal treatment, which is similar with the primary component of bone and has a very good osteo-inductivity.The porous gradient titania coating made by the hybrid oxidation and hydrothermal treatment should show good biocompatibility in the environment of the human body.

  17. Biocompatible coating of encapsulated cells using ionotropic gelation.

    Directory of Open Access Journals (Sweden)

    Friederike Ehrhart

    Full Text Available The technique of immunoisolated transplantation has seen in the last twenty years improvements in biocompatibility, long term stability and methods for avoidance of fibrosis in alginate capsules. However, two major problems are not yet solved: living cellular material that is not centered in the capsule is not properly protected from the hosts' immune system and the total transplant volume needs to be reduced. To solve these problems, we present a method for applying fully biocompatible alginate multilayers to a barium-alginate core without the use of polycations. We report on the factors that influence layer formation and stability and can therefore provide data for full adjustability of the additional layer. Although known for yeast and plant cells, this technique has not previously been demonstrated with mammalian cells or ultra-high viscous alginates. Viability of murine insulinoma cells was investigated by live-dead staining and live cell imaging, for murine Langerhans' islets viability and insulin secretion have been measured. No hampering effects of the second alginate layer were found. This multi-layer technique therefore has great potential for clinical and in vitro use and is likely to be central in alginate matrix based immunoisolated cell therapy.

  18. Biocompatible cellulose-based superabsorbent hydrogels with antimicrobial activity.

    Science.gov (United States)

    Peng, Na; Wang, Yanfeng; Ye, Qifa; Liang, Lei; An, Yuxing; Li, Qiwei; Chang, Chunyu

    2016-02-10

    Current superabsorbent hydrogels commercially applied in the disposable diapers have disadvantages such as weak mechanical strength, poor biocompatibility, and lack of antimicrobial activity, which may induce skin allergy of body. To overcome these hassles, we have developed novel cellulose based hydrogels via simple chemical cross-linking of quaternized cellulose (QC) and native cellulose in NaOH/urea aqueous solution. The prepared hydrogel showed superabsorbent property, high mechanical strength, good biocompatibility, and excellent antimicrobial efficacy against Saccharomyces cerevisiae. The presence of QC in the hydrogel networks not only improved their swelling ratio via electrostatic repulsion of quaternary ammonium groups, but also endowed their antimicrobial activity by attraction of sections of anionic microbial membrane into internal pores of poly cationic hydrogel leading to the disruption of microbial membrane. Moreover, the swelling properties, mechanical strength, and antibacterial activity of hydrogels strongly depended on the contents of quaternary ammonium groups in hydrogel networks. The obtained data encouraged the use of these hydrogels for hygienic application such as disposable diapers.

  19. Metallic zinc exhibits optimal biocompatibility for bioabsorbable endovascular stents.

    Science.gov (United States)

    Bowen, Patrick K; Guillory, Roger J; Shearier, Emily R; Seitz, Jan-Marten; Drelich, Jaroslaw; Bocks, Martin; Zhao, Feng; Goldman, Jeremy

    2015-11-01

    Although corrosion resistant bare metal stents are considered generally effective, their permanent presence in a diseased artery is an increasingly recognized limitation due to the potential for long-term complications. We previously reported that metallic zinc exhibited an ideal biocorrosion rate within murine aortas, thus raising the possibility of zinc as a candidate base material for endovascular stenting applications. This study was undertaken to further assess the arterial biocompatibility of metallic zinc. Metallic zinc wires were punctured and advanced into the rat abdominal aorta lumen for up to 6.5months. This study demonstrated that metallic zinc did not provoke responses that often contribute to restenosis. Low cell densities and neointimal tissue thickness, along with tissue regeneration within the corroding implant, point to optimal biocompatibility of corroding zinc. Furthermore, the lack of progression in neointimal tissue thickness over 6.5months or the presence of smooth muscle cells near the zinc implant suggest that the products of zinc corrosion may suppress the activities of inflammatory and smooth muscle cells.

  20. Three-dimensional biocompatible matrix for reconstructive surgery

    Science.gov (United States)

    Reshetov, I. V.; Starceva, O. I.; Istranov, A. L.; Vorona, B. N.; Lyundup, A. V.; Gulyaev, I. V.; Melnikov, D. V.; Shtansky, D. V.; Sheveyko, A. N.; Andreev, V. A.

    2016-08-01

    A study into the development of an original bioengineered structure for reconstruction of hollow organs is presented. The basis for the structure was the creation of a mesh matrix made from titanium nickelide (NiTi), which has sufficient elasticity and shape memory for the reconstruction of hollow tubular orgrans. In order to increase the cell adhesion on the surface of the matrix, the grid needed to be cleaned of impurities, for which we used an ionic cleaning method. Additional advantages also may enable the application of the bioactive component to grid surface. These features of the matrix may improve the biocompatibility properties of the composite material. In the first stage, a mesh structure was made from NiTi fibers. The properties of the resulting mesh matrix were studied. In the second stage, the degrees of adhesion and cell growth rates in the untreated matrix, the matrix after ionic cleaning and the matrix after ionic cleaning and the application of the bioactive component were compared. The results showed more significant biocompatibility of the titanium nickelide matrix after its ionic cleaning. The ionic cleaning ensures the removal of toxic contaminants, which are a consequence of the technological production process of the material and provide optimal adhesion properties for the fiber surface. The NiTi net matrix with TiCaPCON coating may be the optimal basis for making the hollow elastic organs.

  1. Metallic Zinc Exhibits Optimal Biocompatibility for Bioabsorbable Endovascular Stents

    Science.gov (United States)

    Bowen, Patrick K.; Guillory, Roger J.; Shearier, Emily R.; Seitz, Jan-Marten; Drelich, Jaroslaw; Bocks, Martin; Zhao, Feng; Goldman, Jeremy

    2015-01-01

    Although corrosion resistant bare metal stents are considered generally effective, their permanent presence in a diseased artery is an increasingly recognized limitation due to the potential for long-term complications. We previously reported that metallic zinc exhibited an ideal biocorrosion rate within murine aortas, thus raising the possibility of zinc as a candidate base material for endovascular stenting applications. This study was undertaken to further assess the arterial biocompatibility of metallic zinc. Metallic zinc wires were punctured and advanced into the rat abdominal aorta lumen for up to 6.5 months. This study demonstrated that metallic zinc did not provoke responses that often contribute to restenosis. Low cell densities and neointimal tissue thickness, along with tissue regeneration within the corroding implant, point to optimal biocompatibility of corroding zinc. Furthermore, the lack of progression in neointimal tissue thickness over 6.5 months or the presence of smooth muscle cells near the zinc implant suggest that the products of zinc corrosion may suppress the activities of inflammatory and smooth muscle cells. PMID:26249616

  2. Biocompatibility of beta-stabilizing elements of titanium alloys.

    Science.gov (United States)

    Eisenbarth, E; Velten, D; Müller, M; Thull, R; Breme, J

    2004-11-01

    In comparison to the presently used alpha + beta titanium alloys for biomedical applications, beta-titanium alloys have many advantageous mechanical properties, such as an improved wear resistance, a high elasticity and an excellent cold and hot formability. This will promote their future increased application as materials for orthopaedic joint replacements. Not all elements with beta-stabilizing properties in titanium alloys are suitable for biomaterial applications-corrosion and wear processes cause a release of these alloying elements to the surrounding tissue. In this investigation, the biocompability of alloying elements for beta- and near beta-titanium alloys was tested in order to estimate their suitability for biomaterial components. Titanium (grade 2) and the implant steel X2CrNiMo18153 (AISI 316 L) were tested as reference materials. The investigation included the corrosion properties of the elements, proliferation, mitochondrial activity, cell morphology and the size of MC3T3-E1 cells and GM7373 cells after 7 days incubation in direct contact with polished slices of the metals. The statistical significance was considered by Weir-test and Lord-test (alpha = 0.05). The biocompatibility range of the investigated metals is (decreasing biocompatibility): niobium-tantalum, titanium, zirconium-aluminium-316 L-molybdenum.

  3. The effect of protein corona on doxorubicin release from the magnetic mesoporous silica nanoparticles with polyethylene glycol coating

    Energy Technology Data Exchange (ETDEWEB)

    Pourjavadi, Ali, E-mail: purjavad@sharif.edu; Tehrani, Zahra Mazaheri; Mahmoudi, Negar [Sharif University of Technology, Polymer Research Laboratory, Department of Chemistry (Iran, Islamic Republic of)

    2015-04-15

    In the present work, biocompatible superparamagnetic iron oxide nanoparticles coated by mesoporous silica were used as drug nanocarriers for doxorubicin (Dox; an anticancer drug) delivery. In biological media, the interaction of protein corona layer with the surface of nanoparticles is inevitable. For this reason, we studied the effect of protein corona on drug release from magnetic mesoporous silica nanoparticles (MMSNs) in human plasma medium. Besides, we used hydrophilic and biocompatible polymer, polyethylene glycol (PEG), to decrease protein corona effects. The results showed the increased Dox release from PEGylated MMSNs compared with bare MMSNs. This result indicated that the coating of PEG reduced the wrapping of the protein corona around the nanoparticles. This phenomenon caused increase in Dox release.

  4. Optoperforation of Intact Plant Cells, Spectral Characterization of Alloy Disorder in InAsP Alloys, and Bimetallic Concentric Surfaces for Metal-Enhanced Fluorescence in Upconverting Nanocrystals

    Science.gov (United States)

    Merritt, Travis R.

    The techniques of optoperforation, spectral characterization of alloy disorder, and metal-enhanced uorescence were applied to previously unconsidered or disregarded systems in order to demonstrate that such applications are both feasible and consequential. These applications were the subject of three disparate works and, as such, are independently discussed. Despite being ostensibly restricted to mammalian cells, optoperforation was demonstrated in intact plant cells by means of successful femtosecond-laser-mediated infiltration of a membrane impermeable dextran-conjugated dye into cells of vital Arabidopsis seedling stems. By monitoring the rate of dye uptake, and the reaction of both CFP-expressing vacuoles and nanocellulose substrates, the intensity and exposure time of the perforating laser were adjusted to values that both preserved cell vitality and permitted the laser-assisted uptake of the uorophore. By using these calibrated laser parameters, dye was injected and later observed in targeted cells after 72 hours, all without deleteriously affecting the vital functions of those cells. In the context of alloy disorder, photoluminescence of excitonic transitions in two InAsxP1--x alloys were studied through temperature and magnetic field strength dependencies, as well as compositionally-dependent time-resolved behavior. The spectral shape, behavior of the linewidths at high magnetic fields, and the divergence of the peak positions from band gap behavior at low temperatures indicated that alloy disorder exists in the x=0.40 composition while showing no considerable presence in the x=0.13 composition. The time-resolved photoluminescence spectrum for both compositions feature a fast and slow decay, with the slow decay lifetime in x=0.40 being longer than that of x=0.13, which may be due to carrier migration between localized exciton states in x=0.40. In order to achieve broadband metal-enhanced uorescence in upconverting NaYF4:Yb,Er nanocrystals, two nanocomposite

  5. Intermetallic nanoparticles

    Science.gov (United States)

    Singh, Dileep; Yusufoglu, Yusuf; Timofeeva, Elena; Routbort, Jules

    2015-07-14

    A process for preparing intermetallic nanoparticles of two or more metals is provided. In particular, the process includes the steps: a) dispersing nanoparticles of a first metal in a solvent to prepare a first metal solution, b) forming a reaction mixture with the first metal solution and a reducing agent, c) heating the reaction mixture to a reaction temperature; and d) adding a second metal solution containing a salt of a second metal to the reaction mixture. During this process, intermetallic nanoparticles, which contain a compound with the first and second metals are formed. The intermetallic nanoparticles with uniform size and a narrow size distribution is also provided. An electrochemical device such as a battery with the intermetallic nanoparticles is also provided.

  6. Generation of drugs coated iron nanoparticles through high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Radhika Devi, A.; Murty, B. S. [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Chelvane, J. A. [Defence Metallurgical Research Laboratory, Hyderabad 500058 (India); Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh [Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036 (India)

    2014-03-28

    The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells.

  7. Recent advances in synthesis and surface modification of superparamagnetic iron oxide nanoparticles with silica

    Science.gov (United States)

    Sodipo, Bashiru Kayode; Aziz, Azlan Abdul

    2016-10-01

    Research on synthesis of superparamagnetic iron oxide nanoparticles (SPION) and its surface modification for biomedical applications is of intense interest. Due to superparamagnetic property of SPION, the nanoparticles have large magnetic susceptibility, single magnetic domain and controllable magnetic behaviour. However, owing to easy agglomeration of SPION, surface modification of the magnetic particles with biocompatible materials such as silica nanoparticle has gained much attention in the last decade. In this review, we present recent advances in synthesis of SPION and various routes of producing silica coated SPION.

  8. Lanthanide-Functionalized Hydrophilic Magnetic Hybrid Nanoparticles: Assembly, Magnetic Behaviour, and Photophysical Properties.

    Science.gov (United States)

    Han, Shuai; Tang, Yu; Guo, Haijun; Qin, Shenjun; Wu, Jiang

    2016-12-01

    The lanthanide-functionalized multifunctional hybrid nanoparticles combining the superparamagnetic core and the luminescent europium complex were successfully designed and assembled via layer-by-layer strategy in this work. It is noted that the hybrid nanoparticles were modified by a hydrophilic polymer polyethyleneimine (PEI) through hydrogen bonding which bestowed excellent hydrophilicity and biocompatibility on this material. A bright-red luminescence was observed by fluorescence microscopy, revealing that these magnetic-luminescent nanoparticles were both colloidally and chemically stable in PBS solution. Therefore, the nanocomposite with magnetic resonance response and fluorescence probe property is considered to be of great potential in multi-modal bioimaging and diagnostic applications. PMID:27245169

  9. Nitric oxide-releasing porous silicon nanoparticles

    Science.gov (United States)

    Kafshgari, Morteza Hasanzadeh; Cavallaro, Alex; Delalat, Bahman; Harding, Frances J.; McInnes, Steven JP; Mäkilä, Ermei; Salonen, Jarno; Vasilev, Krasimir; Voelcker, Nicolas H.

    2014-07-01

    In this study, the ability of porous silicon nanoparticles (PSi NPs) to entrap and deliver nitric oxide (NO) as an effective antibacterial agent is tested against different Gram-positive and Gram-negative bacteria. NO was entrapped inside PSi NPs functionalized by means of the thermal hydrocarbonization (THC) process. Subsequent reduction of nitrite in the presence of d-glucose led to the production of large NO payloads without reducing the biocompatibility of the PSi NPs with mammalian cells. The resulting PSi NPs demonstrated sustained release of NO and showed remarkable antibacterial efficiency and anti-biofilm-forming properties. These results will set the stage to develop antimicrobial nanoparticle formulations for applications in chronic wound treatment.

  10. Optical nanoparticles: synthesis and biomedical application

    Science.gov (United States)

    Nhung Tran, Hong; Nghiem, Thi Ha Lien; Thuy Duong Vu, Thi; Chu, Viet Ha; Huan Le, Quang; Nhung Hoang, Thi My; Thanh Nguyen, Lai; Pham, Duc Minh; Thuan Tong, Kim; Hoa Do, Quang; Vu, Duong; Nghia Nguyen, Trong; Tan Pham, Minh; Nguyen Duong, Cao; Thuy Tran, Thanh; Son Vu, Van; Thuy Nguyen, Thi; Nguyen, Thi Bich Ngoc; Tran, Anh Duc; Thuong Trinh, Thi; Nguyen, Thi Thai An

    2015-01-01

    This paper presents a summary of our results on studies of synthesis and biomedical application of optical nanoparticles. Gold, dye-doped silica based and core-shell multifunctional multilayer (SiO2/Au, Fe3O4/SiO2, Fe3O4/SiO2/Au) water-monodispersed nanoparticles were synthesized by chemical route and surface modified with proteins and biocompatible chemical reagents. The particles were conjugated with antibody or aptamer for specific detecting and imaging bacteria and cancer cells. The photothermal effects of gold nanoshells (SiO2/Au and Fe3O4/SiO2/Au) on cells and tissues were investigated. The nano silver substrates were developed for surface enhanced Raman scattering (SERS) spectroscopy to detect melamine.

  11. Multifunctional polypyrrole@fe3o4 nanoparticles for dual-modal imaging and in vivo photothermal cancer therapy

    KAUST Repository

    Tian, Qiwei

    2013-11-27

    Magnetic Fe3O4 crystals are produced in situ on preformed polypyrrole (PPY) nanoparticles by rationally converting the residual Fe species in the synthetic system. The obtained PPY@Fe3O4 composite nanoparticles exhibit good photostability and biocompatibility, and they can be used as multifunctional probes for MRI, thermal imaging, and photothermal ablation of cancer cells. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Investigation of the interaction between magnetic nanoparticles surface-coated with carboxymethyldextran and blood cells using Raman spectroscopy

    International Nuclear Information System (INIS)

    This study reports on in vitro biological tests performed with a biocompatible magnetic fluid based on carboxymethyldextran-coated magnetite nanoparticles (CMDM). Micro Raman spectroscopy was used to investigate the effect of dispersing (CMDM) nanoparticles in mice blood. We focused our investigation in the use of the Raman spectroscopy for monitoring the hemoglobin structural changes, which may be associated with the oxygen-binding process

  13. Preparation and characterization of ferrofluid stabilized with biocompatible chitosan and dextran sulfate hybrid biopolymer as a potential magnetic resonance imaging (MRI) T2 contrast agent.

    Science.gov (United States)

    Tsai, Zei-Tsan; Tsai, Fu-Yuan; Yang, Wei-Cheng; Wang, Jen-Fei; Liu, Chao-Lin; Shen, Chia-Rui; Yen, Tzu-Chen

    2012-11-01

    Chitosan is the deacetylated form of chitin and used in numerous applications. Because it is a good dispersant for metal and/or oxide nanoparticle synthesis, chitosan and its derivatives have been utilized as coating agents for magnetic nanoparticles synthesis, including superparamagnetic iron oxide nanoparticles (SPIONs). Herein, we demonstrate the water-soluble SPIONs encapsulated with a hybrid polymer composed of polyelectrolyte complexes (PECs) from chitosan, the positively charged polymer, and dextran sulfate, the negatively charged polymer. The as-prepared hybrid ferrofluid, in which iron chloride salts (Fe³⁺ and Fe²⁺) were directly coprecipitated inside the hybrid polymeric matrices, was physic-chemically characterized. Its features include the z-average diameter of 114.3 nm, polydispersity index of 0.174, zeta potential of −41.5 mV and iron concentration of 8.44 mg Fe/mL. Moreover, based on the polymer chain persistence lengths, the anionic surface of the nanoparticles as well as the high R2/R1 ratio of 13.5, we depict the morphology of SPIONs as a cluster because chitosan chains are chemisorbed onto the anionic magnetite surfaces by tangling of the dextran sulfate. Finally, the cellular uptake and biocompatibility assays indicate that the hybrid polymer encapsulating the SPIONs exhibited great potential as a magnetic resonance imaging T2 contrast agent for cell tracking. PMID:23203267

  14. Preparation and Characterization of Ferrofluid Stabilized with Biocompatible Chitosan and Dextran Sulfate Hybrid Biopolymer as a Potential Magnetic Resonance Imaging (MRI T2 Contrast Agent

    Directory of Open Access Journals (Sweden)

    Tzu-Chen Yen

    2012-10-01

    Full Text Available Chitosan is the deacetylated form of chitin and used in numerous applications. Because it is a good dispersant for metal and/or oxide nanoparticle synthesis, chitosan and its derivatives have been utilized as coating agents for magnetic nanoparticles synthesis, including superparamagnetic iron oxide nanoparticles (SPIONs. Herein, we demonstrate the water-soluble SPIONs encapsulated with a hybrid polymer composed of polyelectrolyte complexes (PECs from chitosan, the positively charged polymer, and dextran sulfate, the negatively charged polymer. The as-prepared hybrid ferrofluid, in which iron chloride salts (Fe3+ and Fe2+ were directly coprecipitated inside the hybrid polymeric matrices, was physic-chemically characterized. Its features include the z-average diameter of 114.3 nm, polydispersity index of 0.174, zeta potential of −41.5 mV and iron concentration of 8.44 mg Fe/mL. Moreover, based on the polymer chain persistence lengths, the anionic surface of the nanoparticles as well as the high R2/R1 ratio of 13.5, we depict the morphology of SPIONs as a cluster because chitosan chains are chemisorbed onto the anionic magnetite surfaces by tangling of the dextran sulfate. Finally, the cellular uptake and biocompatibility assays indicate that the hybrid polymer encapsulating the SPIONs exhibited great potential as a magnetic resonance imaging T2 contrast agent for cell tracking.

  15. Enhancing photocatalysis in SrTiO3 by using Ag nanoparticles: A two-step excitation model for surface plasmon-enhanced photocatalysis.

    Science.gov (United States)

    Ma, Lei; Sun, Tao; Cai, Hua; Zhou, Zhi-Quan; Sun, Jian; Lu, Ming

    2015-08-28

    Surface plasmon (SP)-enhanced ultraviolet and visible photocatalytic activities of SrTiO3 (STO) are observed after incorporating Ag nanoparticles (Ag-NPs) on STO surfaces. A two-step excitation model is proposed to explain the SP-enhanced photocatalysis. The point of the model is that an electron at the valence band of STO is first excited onto the Fermi level of Ag-NP by the SP field generated on the Ag-NP, and then injected into the conduction band of STO from the SP band, leaving a hole at the valence band of STO. A full redox catalytic reaction at the surface of STO is then available. For Ag-NP incorporated STO, up-converted and inter-band photoluminescence emissions of STO are observed, and nonlinear evolutions of photocatalytic activity with illumination light powers are found. Furthermore, near infrared photocatalysis is detected. These results support the proposed model.

  16. Green chemistry approach for the synthesis of biocompatible graphene

    Directory of Open Access Journals (Sweden)

    Gurunathan S

    2013-07-01

    Full Text Available Sangiliyandi Gurunathan, Jae Woong Han, Jin-Hoi Kim Department of Animal Biotechnology, Konkuk University, Seoul, South Korea Background: Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms isolated from its three-dimensional parent material, graphite. One of the most common methods for preparation of graphene is chemical exfoliation of graphite using powerful oxidizing agents. Generally, graphene is synthesized through deoxygenation of graphene oxide (GO by using hydrazine, which is one of the most widespread and strongest reducing agents. Due to the high toxicity of hydrazine, it is not a promising reducing agent in large-scale production of graphene; therefore, this study focused on a green or sustainable synthesis of graphene and the biocompatibility of graphene in primary mouse embryonic fibroblast cells (PMEFs. Methods: Here, we demonstrated a simple, rapid, and green chemistry approach for the synthesis of reduced GO (rGO from GO using triethylamine (TEA as a reducing agent and stabilizing agent. The obtained TEA reduced GO (TEA-rGO was characterized by ultraviolet (UV–visible absorption spectroscopy, X-ray diffraction (XRD, particle size dynamic light scattering (DLS, scanning electron microscopy (SEM, Raman spectroscopy, and atomic force microscopy (AFM. Results: The transition of graphene oxide to graphene was confirmed by UV–visible spectroscopy. XRD and SEM were used to investigate the crystallinity of graphene and the surface morphologies of prepared graphene respectively. The formation of defects further supports the functionalization of graphene as indicated in the Raman spectrum of TEA-rGO. Surface morphology and the thickness of the GO and TEA-rGO were analyzed using AFM. The presented results suggest that TEA-rGO shows significantly more biocompatibility with PMEFs cells than GO. Conclusion: This is the first report about using TEA as a reducing as well as a stabilizing agent for the

  17. Silk-mediated synthesis and modification of photoluminescent ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Han Jie; Su Huilan, E-mail: hlsu@sjtu.edu.cn; Xu Jia; Song Weiqiang; Gu Yu; Chen Ying [Shanghai Jiao Tong University, State Key Lab of Metal Matrix Composites (China); Moon, Won-Jin [Gwangju Center, Korea Basic Science Institute (Korea, Republic of); Zhang Di, E-mail: zhangdi@sjtu.edu.cn [Shanghai Jiao Tong University, State Key Lab of Metal Matrix Composites (China)

    2012-02-15

    In this article, a bio-inspired silk-mediated method was established to produce natural material-modified photoluminescent zinc oxide nanoparticles (nano-ZnO). Silk fibroin fibers were employed as the reactive substrates to synthesize nano-ZnO, and silk fibroins (SF) were taken as the biocompatible stabilizers to modify dispersed nano-ZnO. As-prepared nano-ZnO were mainly hexagonal phase particles with diameter around 13 nm. The resulting nano-ZnO/SF hybrids displayed orange emission and good biocompatibility in aqueous system.

  18. 75 FR 13556 - Biocompatibles UK Ltd.; Filing of Color Additive Petition

    Science.gov (United States)

    2010-03-22

    ... HUMAN SERVICES Food and Drug Administration Biocompatibles UK Ltd.; Filing of Color Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing that Biocompatibles UK Ltd., has filed a petition proposing that the color...

  19. Analyze of histopathelogical for medical devices and biological material on biocompatibility evaluation

    Institute of Scientific and Technical Information of China (English)

    NIE Wei; JIANG Hua; WANG Li; GUAN Jing-fang; SHI Hong-dao

    2001-01-01

    @@ The toxicity and biocompatibility of medical devices and biological material areprominent facts in evaluation of the material. There are two major methods to evaluate the biocompatibility of biological materials . one kind is to do vivo. The materialor extracts are used to study the effect of the material on the growth, metabolismand proliferation of the histocyte.

  20. Whole genome expression profiling using DNA microarray for determining biocompatibility of polymeric surfaces

    DEFF Research Database (Denmark)

    Stangegaard, Michael; Wang, Zhenyu; Kutter, Jörg Peter;

    2006-01-01

    There is an ever increasing need to find surfaces that are biocompatible for applications like medical implants and microfluidics-based cell culture systems. The biocompatibility of five different surfaces with different hydrophobicity was determined using gene expression profiling as well as more...

  1. Effects of surface finishing conditions on the biocompatibility of a nickel-chromium dental casting alloy.

    LENUS (Irish Health Repository)

    McGinley, Emma Louise

    2011-07-01

    To assess the effects of surface finishing condition (polished or alumina particle air abraded) on the biocompatibility of direct and indirect exposure to a nickel-chromium (Ni-Cr) d.Sign®10 dental casting alloy on oral keratinocytes. Biocompatibility was performed by assessing cellular viability and morphology, metabolic activity, cellular toxicity and presence of inflammatory cytokine markers.

  2. Development of nanostars as a biocompatible tumor contrast agent: toward in vivo SERS imaging

    Directory of Open Access Journals (Sweden)

    D’Hollander A

    2016-08-01

    Full Text Available Antoine D’Hollander,1–3 Evelien Mathieu,1,4 Hilde Jans,1 Greetje Vande Velde,2,3 Tim Stakenborg,1 Pol Van Dorpe,1,4 Uwe Himmelreich,2,3 Liesbet Lagae1,4 1Department of Life Science Technology, Imec, 2Department of Imaging and Pathology, Faculty of Medicine, Biomedical MRI Unit, 3Faculty of Medicine, Molecular Small Animal Imaging Center (MoSAIC, 4Department of Physics, Faculty of Sciences, Laboratory of Solid State Physics and Magnetism, KU Leuven, Leuven, Belgium Abstract: The need for sensitive imaging techniques to detect tumor cells is an important issue in cancer diagnosis and therapy. Surface-enhanced Raman scattering (SERS, realized by chemisorption of compounds suitable for Raman spectroscopy onto gold nanoparticles, is a new method for detecting a tumor. As a proof of concept, we studied the use of biocompatible gold nanostars as sensitive SERS contrast agents targeting an ovarian cancer cell line (SKOV3. Due to a high intracellular uptake of gold nanostars after 6 hours of exposure, they could be detected and located with SERS. Using these nanostars for passive targeting after systemic injection in a xenograft mouse model, a detectable signal was measured in the tumor and liver in vivo. These signals were confirmed by ex vivo SERS measurements and darkfield microscopy. In this study, we established SERS nanostars as a highly sensitive contrast agent for tumor detection, which opens the potential for their use as a theranostic agent against cancer. Keywords: SERS, gold nanostars, cancer imaging, Raman active

  3. Synthesis and characterization of near IR fluorescent albumin nanoparticles for optical detection of colon cancer

    International Nuclear Information System (INIS)

    Near IR (NIR) fluorescent human serum albumin (HSA) nanoparticles hold great promise as contrast agents for tumor diagnosis. HSA nanoparticles are considered to be biocompatible, non-toxic and non-immunogenic. In addition, NIR fluorescence properties of these nanoparticles are important for in vivo tumor diagnostics, with low autofluorescence and relatively deep penetration of NIR irradiation due to low absorption of biomatrices. The present study describes the synthesis of new NIR fluorescent HSA nanoparticles, by entrapment of a NIR fluorescent dye within the HSA nanoparticles, which also significantly increases the photostability of the dye. Tumor-targeting ligands such as peanut agglutinin (PNA) and anti-carcinoembryonic antigen antibodies (anti-CEA) were covalently conjugated to the NIR fluorescent albumin nanoparticles, increasing the potential fluorescent signal in tumors with upregulated corresponding receptors. Specific colon tumor detection by the NIR fluorescent HSA nanoparticles was demonstrated in a chicken embryo model and a rat model. In future work we also plan to encapsulate cancer drugs such as doxorubicin within the NIR fluorescent HSA nanoparticles for both colon cancer imaging and therapy. - Highlights: ► Near IR human serum albumin nanoparticles were synthesized and characterized. ► Nanoparticles were shown to be physically and chemically stable and photostable. ► Tumor-targeting ligands were covalently conjugated to the nanoparticles. ► Specific colon cancer tumor detection was demonstrated in chicken-embryo and rat models.

  4. Synthesis and characterization of near IR fluorescent albumin nanoparticles for optical detection of colon cancer

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Sarit; Pellach, Michal [Department of Chemistry, Bar-Ilan Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 52900 (Israel); Kam, Yossi [Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, P.O. Box 12065, Jerusalem 91120 (Israel); Grinberg, Igor; Corem-Salkmon, Enav [Department of Chemistry, Bar-Ilan Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 52900 (Israel); Rubinstein, Abraham [Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, P.O. Box 12065, Jerusalem 91120 (Israel); Margel, Shlomo, E-mail: shlomo.margel@mail.biu.ac.il [Department of Chemistry, Bar-Ilan Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 52900 (Israel)

    2013-03-01

    Near IR (NIR) fluorescent human serum albumin (HSA) nanoparticles hold great promise as contrast agents for tumor diagnosis. HSA nanoparticles are considered to be biocompatible, non-toxic and non-immunogenic. In addition, NIR fluorescence properties of these nanoparticles are important for in vivo tumor diagnostics, with low autofluorescence and relatively deep penetration of NIR irradiation due to low absorption of biomatrices. The present study describes the synthesis of new NIR fluorescent HSA nanoparticles, by entrapment of a NIR fluorescent dye within the HSA nanoparticles, which also significantly increases the photostability of the dye. Tumor-targeting ligands such as peanut agglutinin (PNA) and anti-carcinoembryonic antigen antibodies (anti-CEA) were covalently conjugated to the NIR fluorescent albumin nanoparticles, increasing the potential fluorescent signal in tumors with upregulated corresponding receptors. Specific colon tumor detection by the NIR fluorescent HSA nanoparticles was demonstrated in a chicken embryo model and a rat model. In future work we also plan to encapsulate cancer drugs such as doxorubicin within the NIR fluorescent HSA nanoparticles for both colon cancer imaging and therapy. - Highlights: Black-Right-Pointing-Pointer Near IR human serum albumin nanoparticles were synthesized and characterized. Black-Right-Pointing-Pointer Nanoparticles were shown to be physically and chemically stable and photostable. Black-Right-Pointing-Pointer Tumor-targeting ligands were covalently conjugated to the nanoparticles. Black-Right-Pointing-Pointer Specific colon cancer tumor detection was demonstrated in chicken-embryo and rat models.

  5. [Neon-colored plastics for orthodontic appliances. Biocompatibility studies].

    Science.gov (United States)

    Schendel, K U; Erdinger, L; Komposch, G; Sonntag, H G

    1995-01-01

    Public concern and issues of liability have made product safety a major concern throughout the medical field including orthodontics. The purpose of this study was to test the biocompatibility of the new neon colored plastic materials to be used for removable orthodontic appliances before they reach the market and are used in patient treatment. In addition, eight modifications of this synthetic material, which has been used in appliances for many years, were examined without neon color. The procedures established tested for: 1. mutagenicity, 2. toxicity, and 3. irritation of the mucous membrane. As alternatives to using animals the Ames Test, the Agar Overlay Assay, and the HET-CAM Test were employed to test for these properties. The tests revealed that, when the manufacturer's instructions are followed, neither the polymerized materials as used in patient appliances nor the shavings resulting from the orthodontist or the technician grinding the appliance exhibit mutagenic, toxic, or irritating properties.

  6. Rapid microfabrication of solvent-resistant biocompatible microfluidic devices.

    Science.gov (United States)

    Hung, Lung-Hsin; Lin, Robert; Lee, Abraham Phillip

    2008-06-01

    This paper presents a rapid, simple, and low-cost fabrication method to prepare solvent resistant and biocompatible microfluidic devices with three-dimensional geometries. The devices were fabricated in thiolene and replicated from PDMS master with high molding fidelity. Good chemical compatibility for organic solvents allows volatile chemicals in synthesis and analysis applications. The surface can be processed to be hydrophobic or hydrophilic for water-in-oil and oil-in-water emulsions. Monodisperse organic solvent droplet generation is demonstrated to be reproducible in thiolene microchannels without swelling. The thiolene surface prevents cell adhesion but normal cell growth and adhesion on glass substrates is not affected by the adjacent thiolene patterns. PMID:18497921

  7. Motion Control of Urea-Powered Biocompatible Hollow Microcapsules.

    Science.gov (United States)

    Ma, Xing; Wang, Xu; Hahn, Kersten; Sánchez, Samuel

    2016-03-22

    The quest for biocompatible microswimmers powered by compatible fuel and with full motion control over their self-propulsion is a long-standing challenge in the field of active matter and microrobotics. Here, we present an active hybrid microcapsule motor based on Janus hollow mesoporous silica microparticles powered by the biocatalytic decomposition of urea at physiological concentrations. The directional self-propelled motion lasts longer than 10 min with an average velocity of up to 5 body lengths per second. Additionally, we control the velocity of the micromotor by chemically inhibiting and reactivating the enzymatic activity of urease. The incorporation of magnetic material within the Janus structure provides remote magnetic control on the movement direction. Furthermore, the mesoporous/hollow structure can load both small molecules and larger particles up to hundreds of nanometers, making the hybrid micromotor an active and controllable drug delivery microsystem. PMID:26863183

  8. Synthesis of biocompatible multicolor luminescent carbon dots for bioimaging applications

    Directory of Open Access Journals (Sweden)

    Nagaprasad Puvvada, B N Prashanth Kumar, Suraj Konar, Himani Kalita, Mahitosh Mandal and Amita Pathak

    2012-01-01

    Full Text Available Water-soluble carbon dots (C-dots were prepared through microwave-assisted pyrolysis of an aqueous solution of dextrin in the presence of sulfuric acid. The C-dots produced showed multicolor luminescence in the entire visible range, without adding any surface-passivating agent. X-ray diffraction and Fourier transform infrared spectroscopy studies revealed the graphitic nature of the carbon and the presence of hydrophilic groups on the surface, respectively. The formation of uniformly distributed C-dots and their luminescent properties were, respectively, revealed from transmission electron microscopy and confocal laser scanning microscopy. The biocompatible nature of C-dots was confirmed by a cytotoxicity assay on MDA-MB-468 cells and their cellular uptake was assessed through a localization study.

  9. Vertically, interconnected carbon nanowalls as biocompatible scaffolds for osteoblast cells

    Science.gov (United States)

    Ion, Raluca; Vizireanu, Sorin; Luculescu, Catalin; Cimpean, Anisoara; Dinescu, Gheorghe

    2016-07-01

    The response of MC3T3-E1 pre-osteoblasts to vertically aligned, interconnected carbon nanowalls prepared by plasma enhanced chemical vapor deposition on silicon substrate has been evaluated in terms of cell adhesion, viability and cell proliferation. The behavior of osteoblasts seeded on carbon nanowalls was analyzed in parallel and compared with the behavior of the cells maintained in contact with tissue culture polystyrene (TCPS). The results demonstrate that osteoblasts adhere and remain viable in the long term on carbon nanowalls. Moreover, on the investigated scaffold cell proliferation was significantly promoted, although to a lower extent than on TCPS. Overall, the successful culture of osteoblasts on carbon nanowalls coated substrate confirms the biocompatibility of this scaffold, which could have potential applications in the development of orthopedic biomaterials.

  10. Biocompatibility of epoxidized styrene-butadiene-styrene block copolymer membrane

    International Nuclear Information System (INIS)

    Styrene-butadiene-styrene block copolymer (SBS) membrane was prepared by solution casting method and then was epoxidized with peroxyformic acid generated in situ to yield the epoxidized styrene-butadiene-styrene block copolymer membrane (ESBS). The structure and properties of ESBS were characterized with infrared spectroscopy, Universal Testing Machine, differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA). The performances of contact angle, water content, protein adsorption, and water vapor transmission rate on ESBS membrane were determined. After epoxidation, the hydrophilicity of the membrane increased. The water vapor transmission rate of ESBS membrane is similar to human skin. The biocompatibility of ESBS membrane was evaluated with the cell culture of fibroblasts on the membrane. It revealed that the cells not only remained viable but also proliferated on the surface of the various ESBS membranes and the population doubling time for fibroblast culture decreased.

  11. Interfacing microbial styrene production with a biocompatible cyclopropanation reaction.

    Science.gov (United States)

    Wallace, Stephen; Balskus, Emily P

    2015-06-01

    The introduction of new reactivity into living organisms is a major challenge in synthetic biology. Despite an increasing interest in both the development of small-molecule catalysts that are compatible with aqueous media and the engineering of enzymes to perform new chemistry in vitro, the integration of non-native reactivity into metabolic pathways for small-molecule production has been underexplored. Herein we report a biocompatible iron(III) phthalocyanine catalyst capable of efficient olefin cyclopropanation in the presence of a living microorganism. By interfacing this catalyst with E. coli engineered to produce styrene, we synthesized non-natural phenyl cyclopropanes directly from D-glucose in single-vessel fermentations. This process is the first example of the combination of nonbiological carbene-transfer reactivity with cellular metabolism for small-molecule production. PMID:25925138

  12. In-plane biocompatible microfluidic interconnects for implantable microsystems.

    Science.gov (United States)

    Johnson, Dean G; Frisina, Robert D; Borkholder, David A

    2011-04-01

    Small mammals, particularly mice, are very useful animal models for biomedical research. Extremely small anatomical dimensions, however, make design of implantable microsystems quite challenging. A method for coupling external fluidic systems to microfluidic channels via in-plane interconnects is presented. Capillary tubing is inserted into channels etched in the surface of a Si wafer with a seal created by Parylene-C deposition. Prediction of Parylene-C deposition into tapered channels based on Knudsen diffusion and deposition characterizations allows for design optimization. Low-volume interconnects using biocompatible, chemical resistant materials have been demonstrated and shown to withstand pressure as high as 827 kPa (120 psi) with an average pull test strength of 2.9 N. Each interconnect consumes less than 0.018 mm3 (18 nL) of volume. The low added volume makes this an ideal interconnect technology for medical applications where implant volume is critical.

  13. Biological response of hydrogels embedding gold nanoparticles.

    Science.gov (United States)

    Marsich, Eleonora; Travan, Andrea; Donati, Ivan; Di Luca, Andrea; Benincasa, Monica; Crosera, Matteo; Paoletti, Sergio

    2011-04-01

    A nanocomposite hydrogel based on natural polysaccharides and gold nanoparticles (ACnAu) has been prepared and its biological effects were tested in vitro with both bacteria and eukaryotic cells. Antimicrobial tests showed that AC-nAu gels are effective in killing both gram+ (Staphylococcus aureus) and gram- (Pseudomonas aeruginosa) bacteria. LDH assays pointed at a toxic effect towards eukaryotic cell-lines (HepG2 and MG63), in contrast with the case of silver-based hydrogels; cytofluorimetry studies demonstrated an apoptosis-related mechanism induced by increase of ROS intracellular level which leads to cell death after 24 h of direct contact with AC-nAu gels. In vivo biocompatibility has been evaluated in a rat model, investigating the peri-implant soft tissue reaction after 1 month of implantation. The results show that silver-containing samples induced a fibrotic capsule of the same average thickness of the control sample (devoid of nanoparticles) (∼50 μm), while in the case of gold containing materials the fibrotic capsule was thicker (∼100 μm), confirming a higher biocompatibility for silver-based samples than for gold-based ones.

  14. Biocompatibility of chitosan/Mimosa tenuiflora scaffolds for tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Martel-Estrada, Santos Adriana [Instituto de arquitectura diseño y arte, Universidad Autónoma de Ciudad Juárez, Ave. Del Charro #610 norte, Col. Partido Romero, C.P. 32320 Cd. Juárez, Chihuahua (Mexico); Rodríguez-Espinoza, Brenda [Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Anillo envolvente del PRONAF y Estocolmo, C.P. 32320 Cd. Juárez, Chihuahua (Mexico); Santos-Rodríguez, Elí [ICTP Meso-American Centre for Theoretical Physics (ICTP-MCTP)/Universidad Autónoma de Chiapas, Ciudad Universitaria, Carretera Zapata Km. 4, Real del Bosque (Terán), C.P. 29040 Tuxtla Gutiérrez, Chiapas (Mexico); Jiménez-Vega, Florinda [Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Anillo envolvente del PRONAF y Estocolmo, C.P. 32320 Cd. Juárez, Chihuahua (Mexico); García-Casillas, Perla E.; Martínez-Pérez, Carlos A. [Instituto de Ingeniería y Tecnología, Universidad Autónoma de Ciudad Juárez, Ave. Del Charro #610 norte, Col. Partido Romero, C.P. 32320 Cd. Juárez, Chihuahua (Mexico); and others

    2015-09-15

    Highlights: • The porosity of the composites allow biological processes for the cell adaptation on the scaffolds. • The composites improve the viability and proliferation of cells. • Composition of the scaffold plays an important role in the biocompatibility. • The results indicate that Mimosa Tenuiflora can induce the differentiation of osteoblast cells. - Abstract: In search of a plant that exhibits osteogenic activity, Mimosa tenuiflora (M. tenuiflora) cortex represents the opportunity to create a biomaterial that, together with the chitosan, is osteoconductive and promote better and rapid regeneration of bone tissue. Thus, the composite of chitosan/M. tenuiflora cortex fabricated will have properties of biocompatibility and allow the osteoblast proliferation. Composites were developed with different concentrations of chitosan/M. tenuiflora cortex (w/w) using thermally induced phase separation technique (TIPS). To analyze the effects of composite on osteoblasts, primary cultures, each sample was collected on days 1, 3 and 7 after seeding. The evaluation of composites consisted of viability and proliferation tests in which we observed the metabolic activity of the cells using MTT reagent and determined the DNA concentration by means of fluorescence. The expression of the marker alkaline phosphatase (ALP) using p-nitrophenyl phosphate was examined, allowing the observation to the activity of proliferation and differentiation of osteoblastic cells. Moreover, an analysis of biomineralization was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy, infrared spectroscopy and X-ray diffraction. The results showed that 80/20 chitosan/M. tenuiflora cortex biocomposite has the best performance with osteoblasts compared to biomaterials 100/0 and 70/30 chitosan/M. tenuiflora composites. Finally, it was determined that the composite of chitosan/M. tenuiflora cortex presents no cytotoxicity and increases the capacity of the osteoblasts

  15. How hydrophobically modified chitosans are stabilized by biocompatible lipid aggregates.

    Science.gov (United States)

    Ruocco, Nino; Frielinghaus, Heide; Vitiello, Giuseppe; D'Errico, Gerardino; Leal, Leslie G; Richter, Dieter; Ortona, Ornella; Paduano, Luigi

    2015-08-15

    Nanostructured hydrogels composed by biocompatible molecules are formulated and characterized. They are based on a polymer network formed by hydrophobically modified chitosans (HMCHIT or CnCHIT) in which vesicles of monoolein (MO) and oleic acid or sodium oleate (NaO), depending on pH, are embedded. The best conditions for gel formation, in terms of pH, length of the hydrophobic moieties of chitosan, and weight proportion among the three components were estimated by visual inspection of a large number of samples. Among all possible combinations, the system C12CHIT-MO-NaO in the weight proportion (1:1:1) is optimal for the formation of a well-structured gel-like system, which is also confirmed by rheological experiments. Electron paramagnetic resonance (EPR) measurements unambiguously show the presence of lipid bilayers in this mixture, indicating that MO-NaO vesicles are stabilized by C12CHIT even at acid pH. A wide small angle neutron scattering investigation performed on several ternary systems of general formula CnCHIT-MO-NaO shows that the length of the hydrophobic tail Cn is a crucial parameter in stabilizing the polymer network in which lipid vesicles are embedded. Structural parameters for the vesicles are determined by using a multilamellar model that admits the possibility of displacement of the center of each shell. The number of shells tends to be reduced by increasing the polymer content. The thickness and the distance between consecutive lamellae are not influenced by either the polymer or MO-NaO concentration. The hydrogel presented in this work, being fully biocompatible and nanostructured, is well-suited for possible application in drug delivery. PMID:25935287

  16. Biocompatibility of chitosan/Mimosa tenuiflora scaffolds for tissue engineering

    International Nuclear Information System (INIS)

    Highlights: • The porosity of the composites allow biological processes for the cell adaptation on the scaffolds. • The composites improve the viability and proliferation of cells. • Composition of the scaffold plays an important role in the biocompatibility. • The results indicate that Mimosa Tenuiflora can induce the differentiation of osteoblast cells. - Abstract: In search of a plant that exhibits osteogenic activity, Mimosa tenuiflora (M. tenuiflora) cortex represents the opportunity to create a biomaterial that, together with the chitosan, is osteoconductive and promote better and rapid regeneration of bone tissue. Thus, the composite of chitosan/M. tenuiflora cortex fabricated will have properties of biocompatibility and allow the osteoblast proliferation. Composites were developed with different concentrations of chitosan/M. tenuiflora cortex (w/w) using thermally induced phase separation technique (TIPS). To analyze the effects of composite on osteoblasts, primary cultures, each sample was collected on days 1, 3 and 7 after seeding. The evaluation of composites consisted of viability and proliferation tests in which we observed the metabolic activity of the cells using MTT reagent and determined the DNA concentration by means of fluorescence. The expression of the marker alkaline phosphatase (ALP) using p-nitrophenyl phosphate was examined, allowing the observation to the activity of proliferation and differentiation of osteoblastic cells. Moreover, an analysis of biomineralization was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy, infrared spectroscopy and X-ray diffraction. The results showed that 80/20 chitosan/M. tenuiflora cortex biocomposite has the best performance with osteoblasts compared to biomaterials 100/0 and 70/30 chitosan/M. tenuiflora composites. Finally, it was determined that the composite of chitosan/M. tenuiflora cortex presents no cytotoxicity and increases the capacity of the osteoblasts

  17. Biocompatibility of Advanced Manufactured Titanium Implants—A Review

    Directory of Open Access Journals (Sweden)

    Alfred T. Sidambe

    2014-12-01

    Full Text Available Titanium (Ti and its alloys may be processed via advanced powder manufacturing routes such as additive layer manufacturing (or 3D printing or metal injection moulding. This field is receiving increased attention from various manufacturing sectors including the medical devices sector. It is possible that advanced manufacturing techniques could replace the machining or casting of metal alloys in the manufacture of devices because of associated advantages that include design flexibility, reduced processing costs, reduced waste, and the opportunity to more easily manufacture complex or custom-shaped implants. The emerging advanced manufacturing approaches of metal injection moulding and additive layer manufacturing are receiving particular attention from the implant fabrication industry because they could overcome some of the difficulties associated with traditional implant fabrication techniques such as titanium casting. Using advanced manufacturing, it is also possible to produce more complex porous structures with improved mechanical performance, potentially matching the modulus of elasticity of local bone. While the economic and engineering potential of advanced manufacturing for the manufacture of musculo-skeletal implants is therefore clear, the impact on the biocompatibility of the materials has been less investigated. In this review, the capabilities of advanced powder manufacturing routes in producing components that are suitable for biomedical implant applications are assessed with emphasis placed on surface finishes and porous structures. Given that biocompatibility and host bone response are critical determinants of clinical performance, published studies of in vitro and in vivo research have been considered carefully. The review concludes with a future outlook on advanced Ti production for biomedical implants using powder metallurgy.

  18. Synthesis of stable carboxy-terminated NaYF4: Yb3+, Er3+@SiO2 nanoparticles with ultrathin shell for biolabeling applications

    Science.gov (United States)

    Liu, Fuyao; Zhao, Qi; You, Hongpeng; Wang, Zhenxin

    2013-01-01

    Here, a two-step method has been developed for synthesizing carboxy-terminated NaYF4: Yb3+, Er3+@SiO2 core@shell nanoparticles (UCNP@SiO2) with ultrathin shell (1.5 nm). First, the NaYF4: Yb3+, Er3+ upconverting nanoparticles (UCNPs) were prepared using solvothermal technology; then, silica shells (SiO2) were deposited on the nanocrystals to form core-shell structures by the hydrolysis of tetraethylorthosilicate (TEOS). The ultrathin SiO2 shell was obtained by increasing surfactant amount and decreasing TEOS amount in the reaction mixture. Carboxyethylsilanetriol (CTES) was used to generate the carboxy group on the particle surface. The carboxy-terminated UCNP@SiO2 are ideally suited for biolabeling and bioimaging applications because the as-prepared nanoparticles have extreme colloidal and optical stabilities, and the carboxy groups on the particle surface easily react with amino residues of biomolecules. As an example, we reported on the interactions of Ricinus Communis Agglutinin (RCA 120) conjugated UCNP@SiO2 with HeLa cells. The excellent performance of the RCA 120 conjugated UCNP@SiO2 in cellular fluorescence imaging was demonstrated.Here, a two-step method has been developed for synthesizing carboxy-terminated NaYF4: Yb3+, Er3+@SiO2 core@shell nanoparticles (UCNP@SiO2) with ultrathin shell (1.5 nm). First, the NaYF4: Yb3+, Er3+ upconverting nanoparticles (UCNPs) were prepared using solvothermal technology; then, silica shells (SiO2) were deposited on the nanocrystals to form core-shell structures by the hydrolysis of tetraethylorthosilicate (TEOS). The ultrathin SiO2 shell was obtained by increasing surfactant amount and decreasing TEOS amount in the reaction mixture. Carboxyethylsilanetriol (CTES) was used to generate the carboxy group on the particle surface. The carboxy-terminated UCNP@SiO2 are ideally suited for biolabeling and bioimaging applications because the as-prepared nanoparticles have extreme colloidal and optical stabilities, and the carboxy

  19. Endothelial biocompatibility and accumulation of SPION under flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Matuszak, Jasmin; Zaloga, Jan; Friedrich, Ralf P.; Lyer, Stefan [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany); Nowak, Johannes; Odenbach, Stefan [Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, Dresden (Germany); Alexiou, Christoph [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany); Cicha, Iwona, E-mail: Iwona_Cicha@yahoo.com [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany)

    2015-04-15

    Magnetic targeting is considered a promising method to accumulate the nanoparticles at the sites of atherosclerotic lesions, but little is known about the biological effects of magnetic nanoparticles on the vascular wall. Here, we investigated endothelial cell growth and vitality upon treatment with SPION (0–60 µg/mL) using two complementing methods: real-time cell analysis and live-cell microscopy. Moreover, the uptake of circulating superparamagnetic iron oxide nanoparticles (SPIONs) was assessed in an in vitro model of arterial bifurcations. At the tested concentrations, SPIONs were well tolerated and had no major influence on endothelial cell growth. Our results further showed a uniform distribution of endothelial SPION uptake independent of channel geometry or hemodynamic conditions: In the absence of magnetic force, no increase in accumulation of SPIONs at non-uniform shear stress region at the outer walls of bifurcation was observed. Application of external magnet allowed enhanced accumulation of SPIONs at the regions of non-uniform shear stress. Increased uptake of SPIONs at non-uniform shear stress region was well tolerated by endothelial cells (ECs) and did not affect endothelial cell viability or attachment. These findings indicate that magnetic targeting can constitute a promising and safe technique for the delivery of imaging and therapeutic nanoparticles to atherosclerotic lesions.

  20. Plasmon enhanced upconversion luminescence near gold nanoparticles–simulation and analysis of the interactions

    OpenAIRE

    Fischer, Stefan; Hallermann, Florian; Eichelkraut, Toni; von Plessen, Gero; Krämer, Karl W.; Biner, Daniel; Steinkemper, Heiko; Hermle, Martin; Goldschmidt, Jan C.

    2011-01-01

    We investigate plasmon resonances in gold nanoparticles to enhance the quantum yield of upconverting materials. For this purpose, we use a rate equation model that describes the upconversion of trivalent erbium based upconverters. Changes of the optical field acting on the upconverter and the changes to the transition probabilities of the upconverter in the proximity of a gold nanoparticle are calculated using Mie theory and exact electrodynamic theory respectively. With this data, the influe...

  1. Synthesis of improved upconversion nanoparticles as ultrasensitive fluorescence probe for mycotoxins.

    Science.gov (United States)

    Chen, Quansheng; Hu, Weiwei; Sun, Cuicui; Li, Huanhuan; Ouyang, Qin

    2016-09-28

    Rare earth-doped upconversion nanoparticles (UCNPs) have promising potentials in biodetection due to their unique frequency upconverting capability and high detection sensitivity. This paper reports an improved UCNPs-based fluorescence probe for dual-sensing of Aflatoxin B1 (AFB1) and Deoxynivalenol (DON) using a magnetism-induced separation and the specific formation of antibody-targets complex. Herein, the improved UCNPs, which were namely NaYF4:Yb/Ho/Gd and NaYF4:Yb/Tm/Gd, were systematically studied based on the optimization of reaction time, temperature and the concentration of dopant ions with simultaneous phase and size controlled NaYF4 nanoparticles; and the targets were detected using the pattern of competitive combination assay. Under an optimized condition, the advanced fluorescent probes revealed stronger fluorescent properties, broader biological applications and better storage stabilities compared to traditional UCNPs-based ones; and ultrasensitive determinations of AFB1 and DON were achieved under a wide sensing range of 0.001-0.1 ng ml(-1) with the limit of detection (LOD) of 0.001 ng ml(-1). Additionally, the applicability of the improved nanosensor for the detection of mycotoxins was also confirmed in adulterated oil samples. PMID:27619096

  2. Dye-doped silica-based nanoparticles for bioapplications

    International Nuclear Information System (INIS)

    This paper presents our recent research results on synthesis and bioapplications of dye-doped silica-based nanoparticles. The dye-doped water soluble organically modified silicate (ORMOSIL) nanoparticles (NPs) with the size of 15–100 nm were synthesized by modified Stöber method from methyltriethoxysilane CH3Si(OCH3)3 precursor (MTEOS). Because thousands of fluorescent dye molecules are encapsulated in the silica-based matrix, the dye-doped nanoparticles are extremely bright and photostable. Their surfaces were modified with bovine serum albumin (BSA) and biocompatible chemical reagents. The highly intensive luminescent nanoparticles were combined with specific bacterial and breast cancer antigen antibodies. The antibody-conjugated nanoparticles can identify a variety of bacterium, such as Escherichia coli O157:H7, through antibody–antigen interaction and recognition. A highly sensitive breast cancer cell detection has been achieved with the anti-HER2 monoclonal antibody–nanoparticles complex. These results demonstrate the potential to apply these fluorescent nanoparticles in various biodetection systems. (reviews)

  3. Iron oxide and gold nanoparticles in cancer therapy

    Science.gov (United States)

    Gotman, Irena; Psakhie, Sergey G.; Lozhkomoev, Aleksandr S.; Gutmanas, Elazar Y.

    2016-08-01

    Continuous research activities in the field of nanomedicine in the past decade have, to a great extent, been focused on nanoparticle technologies for cancer therapy. Gold and iron oxide nanoparticles (NP) are two of the most studied inorganic nanomaterials due to their unique optical and magnetic properties. Both types of NPs are emerging as promising systems for anti-tumor drug delivery and for nanoparticle-mediated thermal therapy of cancer. In thermal therapy, localized heating inside tumors or in proximity of tumor cells can be induced, for example, with Au NPs by radiofrequency ablation heating or conversion of photon energy (photothermal therapy) and in iron oxide magnetic NPs by heat generation through relaxation in an alternating magnetic field (magnetic hyperthermia). Furthermore, the superparamagnetic properties of iron oxide nanoparticles have led to their use as potent MRI (magnetic resonance imaging) contrast agents. Surface modification/coating can produce NPs with tailored and desired properties, such as enhanced blood circulation time, stability, biocompatibility and water solubility. To target nanoparticles to specific tumor cells, NPs should be conjugated with targeting moieties on the surface which bind to receptors or other molecular structures on the cell surface. The article presents several approaches to enhancing the specificity of Au and iron oxide nanoparticles for tumor tissue by appropriate surface modification/functionalization, as well as the effect of these treatments on the saturation magnetization value of iron oxide NPs. The use of other nanoparticles and nanostructures in cancer treatment is also briefly reviewed.

  4. Alginate Nanoparticles as a Promising Adjuvant and Vaccine Delivery System

    Directory of Open Access Journals (Sweden)

    F Sarei

    2013-01-01

    Full Text Available During last decades, diphtheria has remained as a serious disease that still outbreaks and can occur worldwide. Recently, new vaccine delivery systems have been developed by using the biodegradable and biocompatible polymers such as alginate. Alginate nanoparticles as a carrier with adjuvant and prolong release properties that enhance the immunogenicity of vaccines. In this study diphtheria toxoid loaded nanoparticles were prepared by ionic gelation technique and characterized with respect to size, zeta potential, morphology, encapsulation efficiency, release profile, and immunogenicity. Appropriate parameters (calcium chloride and sodium alginate concentration, homogenization rate and homogenization time redounded to the formation of suitable nanoparticles with a mean diameter of 70±0.5 nm. The loading studies of the nanoparticles resulted in high loading capacities (>90% and subsequent release studies showed prolong profile. The stability and antigenicity of toxoid were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and ouchterlony test and proved that the encapsulation process did not affect the antigenic integrity and activity. Guinea pigs immunized with the diphtheria toxoid-loaded alginate nanoparticles showed highest humoral immune response than conventional vaccine. It is concluded that, with regard to the desirable properties of nanoparticles and high immunogenicity, alginate nanoparticles could be considered as a new promising vaccine delivery and adjuvant system.

  5. Design and development of hydrogel nanoparticles for mercaptopurine

    Directory of Open Access Journals (Sweden)

    V Senthil

    2010-01-01

    Full Text Available Hydrogel nanoparticles have gained attention in recent years as they demonstrate the features and characters of hydrogels and nanoparticles at the same time. In the present study chitosan and carrageenan have been used, as hydrogel nanoparticles of mercaptopurine are developed using natural, biodegradable, and biocompatible polymers like chitosan and carrageenan. As these polymers are hydrophilic in nature, the particles will have a long life span in systemic circulation. Hydrogel nanoparticles with mercaptopurine is form an antileukemia drug by the counter polymer gelation method. Fourier-Transform Infrared (FT-IR studies have shown a compatibility of polymers with the drug. The diameter of hydrogel nanoparticles was about 370 - 800 nm with a positive zeta potential of 26 - 30 mV. The hydrogel nanoparticles were almost spherical in shape, as revealed by scanning electron microscopy (SEM. Drug loading varied from 9 to 17%. Mercaptopurine released from the nanoparticles at the end of the twenty-fourth hour was about 69.48 - 76.52% at pH 7.4. The drug release from the formulation was following zero order kinetics, which was evident from the release kinetic studies and the mechanism of drug release was anomalous diffusion, which indicated that the drug release was controlled by more than one process.

  6. pH-dependent anticancer drug release from silk nanoparticles.

    Science.gov (United States)

    Seib, F Philipp; Jones, Gregory T; Rnjak-Kovacina, Jelena; Lin, Yinan; Kaplan, David L

    2013-12-01

    Silk has traditionally been used as a suture material because of its excellent mechanical properties and biocompatibility. These properties have led to the development of different silk-based material formats for tissue engineering and regenerative medicine. Although there have been a small number of studies about the use of silk particles for drug delivery, none of these studies have assessed the potential of silk to act as a stimulus-responsive anticancer nanomedicine. This report demonstrates that an acetone precipitation of silk allows the formation of uniform silk nanoparticles (98 nm diameter, polydispersity index 0.109), with an overall negative surface charge (-33.6 ± 5.8 mV), in a single step. Silk nanoparticles are readily loaded with doxorubicin (40 ng doxorubicin/μg silk) and show pH-dependent release (pH 4.5≫ 6.0 > 7.4). In vitro studies with human breast cancer cell lines demonstrates that the silk nanoparticles are not cytotoxic (IC50 > 120 μg mL(-1) ) and that doxorubicin-loaded silk nanoparticles are able to overcome drug resistance mechanisms. Live cell fluorescence microscopy studies show endocytic uptake and lysosomal accumulation of silk nanoparticles. In summary, the pH-dependent drug release and lysosomal accumulation of silk nanoparticles demonstrate the ability of drug-loaded silk nanoparticles to serve as a lysosomotropic anticancer nanomedicine.

  7. Supramolecular Hydrogel from Nanoparticles and Cyclodextrins for Local and Sustained Nanoparticle Delivery.

    Science.gov (United States)

    Xu, Shuxin; Yin, Li; Xiang, Yuzhang; Deng, Hongzhang; Deng, Liandong; Fan, Hongxia; Tang, Hua; Zhang, Jianhua; Dong, Anjie

    2016-08-01

    Injectable and biodegradable supramolecular hydrogel mPECT NP/α-CD(gel) composed of high-concentration nanoparticle dispersion (≤20% W/V) and α-cyclodextrins (α-CD) are prepared by a two-level physical cross-linking using amphiphilic block polymer methoxy poly(ethylene glycol)-b-poly(ε-caprolactone-co-1,4,8-trioxa[4.6]spiro-9-undecanone) (mPECT) and α-CD. The gelation behavior depends on the concentration of nanoparticles and α-CD. The viscoelasticity and shear thinning of mPECT NP/α-CD(gel) are confirmed. In vitro hydrogel erosion is demonstrated to be mainly a concentration-dependent dissociation process with general release of discrete mPECT nanoparticles about 50 nm that can be easily taken up by cells. The in vitro release behavior can be modulated by changing the concentration of nanoparticles or α-CD. In vitro and in vivo cytotoxicity study demonstrates its biocompatibility and biosafety. Gel formation after subcutaneous injection is also confirmed and mPECT NP/α-CD(gel) shows about 2 weeks retention time. This work validates the potential application for this supramolecular hydrogel in local and sustained delivery of nanoparticles. PMID:27105589

  8. Drug nanoparticles by emulsion-freeze-drying via the employment of branched block copolymer nanoparticles.

    Science.gov (United States)

    Wais, Ulrike; Jackson, Alexander W; Zuo, Yanming; Xiang, Yu; He, Tao; Zhang, Haifei

    2016-01-28

    A large percentage of drug compounds exhibit low water solubility and hence low bioavailability and therapeutic efficacy. This may be addressed by preparation of drug nanoparticles, leading to enhanced dissolution rate and direct use for treatment. Various methods have been developed to produce drug nanocrystals, including wet milling, homogenization, solution precipitation, emulsion diffusion, and the recently developed emulsion freeze-drying. The drawback for these methods may include difficult control in particles size, use of surfactants & polymer, and low ratio of drug to stabilizer. Here, biocompatible branched block copolymer nanoparticles with lightly-crosslinked hydrophobic core and hydrophilic surface groups are synthesized by the direct monomer-to-particle methodology, characterized, and then used as scaffold polymer/surfactant to produce drug nanoparticles via the emulsion-freeze-drying approach. This method can be used for model organic dye and different poorly water-soluble drugs. Aqueous drug nanoparticle dispersions can be obtained with high ratio of drug to stabilizer and relatively uniform nanoparticle sizes. PMID:26704935

  9. SURFACE MODIFITED MAGNETIC NANOPARTICLES FOR BIOMEDICAL APPLICATION

    Directory of Open Access Journals (Sweden)

    G. Yu. Vasyukov

    2015-12-01

    Full Text Available Unique physicochemical properties of nanomaterials arouse a great interest of specialists of various fields. Materials based on nanostructures purchase new mechanical, optical, and electrical properties. Great practical importance is the magnetic properties of materials, structural elements which lie at the nanoscale. Nanomaterials with magnetic properties have been used in drug delivery, magnetic hyperthermia, magnetic separation, and magnetic resonance imaging. Magnetic properties of nanoparticles depend on many factors, such as particle size and shape, chemical properties and lattice type. Magnetic characteristics can be changed by the interaction of particles with the surrounding matrix and neighboring particles.Unfortunately, many studies show that a great disadvantage of the unmodified nanoparticles is their non-specific interaction with the cells, which leads to their accumulation outside the target organs, also to­xicity of nanomaterials and their low colloidal stability. Surface modification of nanoparticles can solve this problem. Development of nanostructures based on magnetic nanoparticles and functionalized by biocompatible agents is one of the main targets of nanobiotechnology.

  10. Gold Nanoparticles: Synthesis, Stability Test, and Application for the Rice Growth

    Directory of Open Access Journals (Sweden)

    Aiwu Wang

    2014-01-01

    Full Text Available In today’s science, with the use of nanotechnology, nanomaterials, which behave very differently from the bulk solid, can be made. One of the capable uses of nanomaterials is bioapplications which make good use of the specific properties of nanoparticles. However, since the nanoparticles will be used both in-vivo and in-vitro, their stability is an important issue to the scientists, concern. In this dissertation, we are going to test the stability of gold nanoparticles in a number of media including the biocompatible medium and their behaviors will be illustrated in terms of optical properties change and aggregation degree. Herein, we report the synthesis of gold nanoparticles of different shapes and applications for the rice growth with significant difference. The gold nanoparticles can inhibit the elongation of rice root without inhibiting the germination of rice seeds.

  11. The cytotoxicity of iron oxide nanoparticles with different modifications evaluated in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zavisova, Vlasta, E-mail: zavisova@saske.sk [Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice (Slovakia); Koneracka, Martina; Kovac, Jozef; Kubovcikova, Martina; Antal, Iryna; Kopcansky, Peter [Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice (Slovakia); Bednarikova, Monika; Muckova, Marta [hameln, rds a.s, Horna 36, 900 01 Modra (Slovakia)

    2015-04-15

    The toxicity of magnetite nanoparticles modified with bioavailable materials such as dextran, bovine serum albumin, polyethylene glycol, and polyvinylpyrrolidone was studied in normal and cancer cells. The size distribution and magnetic properties of the modified magnetic nanoparticles were characterized by different techniques. Transmission electron microscopy showed a nearly spherical shape of the magnetite core with diameters ranging from 4 to 11 nm. Dynamic light scattering was employed to monitor the hydrodynamic size and colloidal stability of the magnetic nanoparticles: Z-average hydrodynamic diameter was between 53 and 69 nm and zeta potential in the range from −35 to −48 mV. Saturation magnetization of the modified nanoparticles was 55–64 emu/g{sub Fe3O4}. Prepared biocompatible nanoparticles had no significant toxic effect on Chinese hamster lung fibroblast cell line V79, but they substantially affected mouse melanoma B16 cell line.

  12. Bioactive Glass Nanoparticles: From Synthesis to Materials Design for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Charlotte Vichery

    2016-04-01

    Full Text Available Thanks to their high biocompatibility and bioactivity, bioactive glasses are very promising materials for soft and hard tissue repair and engineering. Because bioactivity and specific surface area intrinsically linked, the last decade has seen a focus on the development of highly porous and/or nano-sized materials. This review emphasizes the synthesis of bioactive glass nanoparticles and materials design strategies. The first part comprehensively covers mainly soft chemistry processes, which aim to obtain dispersible and monodispersed nanoparticles. The second part discusses the use of bioactive glass nanoparticles for medical applications, highlighting the design of materials. Mesoporous nanoparticles for drug delivery, injectable systems and scaffolds consisting of bioactive glass nanoparticles dispersed in a polymer, implant coatings and particle dispersions will be presented.

  13. Carbon nanoparticles trapped in vivo-similar to carbon nanotubes in time-dependent biodistribution.

    Science.gov (United States)

    Liu, Jia-Hui; Yang, Sheng-Tao; Wang, Xin; Wang, Haifang; Liu, Yamin; Luo, Pengju G; Liu, Yuanfang; Sun, Ya-Ping

    2014-08-27

    Carbon nanoparticles are in all of the carbon nanomaterials that are presently widely pursued for potential bioapplications, but their in vivo biodistribution-related properties are largely unknown. In this work, highly (13)C-enriched carbon nanoparticles were prepared to allow their quantification in biological samples by using isotope-ratio mass spectroscopy. The in vivo biodistribution results are presented and discussed, and also compared with those of the aqueous suspended carbon nanotubes reported previously. The distribution profile and time dependencies are largely similar between the nanoparticles and nanotubes, with results on both suggesting meaningful accumulation in some major organs over an extended period of time. Therefore, the surface modification of carbon nanoparticles, preferably the chemical functionalization of the nanoparticles with biocompatible molecules or species, is desirable or necessary in the pursuit of these nanomaterials for various bioapplications.

  14. The cytotoxicity of iron oxide nanoparticles with different modifications evaluated in vitro

    International Nuclear Information System (INIS)

    The toxicity of magnetite nanoparticles modified with bioavailable materials such as dextran, bovine serum albumin, polyethylene glycol, and polyvinylpyrrolidone was studied in normal and cancer cells. The size distribution and magnetic properties of the modified magnetic nanoparticles were characterized by different techniques. Transmission electron microscopy showed a nearly spherical shape of the magnetite core with diameters ranging from 4 to 11 nm. Dynamic light scattering was employed to monitor the hydrodynamic size and colloidal stability of the magnetic nanoparticles: Z-average hydrodynamic diameter was between 53 and 69 nm and zeta potential in the range from −35 to −48 mV. Saturation magnetization of the modified nanoparticles was 55–64 emu/gFe3O4. Prepared biocompatible nanoparticles had no significant toxic effect on Chinese hamster lung fibroblast cell line V79, but they substantially affected mouse melanoma B16 cell line

  15. Polyurethane and polyurea nanoparticles based on polyoxyethylene castor oil derivative surfactant suitable for endovascular applications.

    Science.gov (United States)

    Morral-Ruíz, Genoveva; Melgar-Lesmes, Pedro; García, María Luísa; Solans, Conxita; García-Celma, María José

    2014-01-30

    The design of new, safe and effective nanotherapeutic systems is an important challenge for the researchers in the nanotechnology area. This study describes the formation of biocompatible polyurethane and polyurea nanoparticles based on polyoxyethylene castor oil derivative surfactant formed from O/W nano-emulsions by polymerization at the droplet interfaces in systems composed by aqueous solution/Kolliphor(®) ELP/medium chain triglyceride suitable for intravenous administration. Initial nano-emulsions incorporating highly hydrophilic materials were prepared by the phase inversion composition (PIC) method. After polymerization, nanoparticles with a small particle diameter (25-55 nm) and low polydispersity index were obtained. Parameters such as concentration of monomer, O/S weight ratio as well as the polymerization temperature were crucial to achieve a correct formation of these nanoparticles. Moreover, FT-IR studies showed the full conversion of the monomer to polyurethane and polyurea polymers. Likewise the involvement of the surfactant in the polymerization process through their nucleophilic groups to form the polymeric matrix was demonstrated. This could mean a first step in the development of biocompatible systems formulated with polyoxyethylene castor oil derivative surfactants. In addition, haemolysis and cell viability assays evidenced the good biocompatibility of KELP polyurethane and polyurea nanoparticles thus indicating the potential of these nanosystems as promising drug carriers.

  16. Ca alginate as scaffold for iron oxide nanoparticles synthesis

    Directory of Open Access Journals (Sweden)

    P. V. Finotelli

    2008-12-01

    Full Text Available Recently, nanotechnology has developed to a stage that makes it possible to process magnetic nanoparticles for the site-specific delivery of drugs. To this end, it has been proposed as biomaterial for drug delivery system in which the drug release rates would be activated by a magnetic external stimuli. Alginate has been used extensively in the food, pharmaceutical and biomedical industries for their gel forming properties in the presence of multivalent cations. In this study, we produced iron oxide nanoparticles by coprecipitation of Fe(III and Fe(II. The nanoparticles were entrapped in Ca alginate beads before and after alginate gelation. XRD analysis showed that particles should be associated to magnetite or maghemite with crystal size of 9.5 and 4.3 nm, respectively. Studies using Mössbauer spectroscopy corroborate the superparamagnetic behavior. The combination of magnetic properties and the biocompatibility of alginate suggest that this biomaterial may be used as biomimetic system.

  17. In Vitro Biocompatibility of Si Alloyed Multi-Principal Element Carbide Coatings.

    Science.gov (United States)

    Vladescu, Alina; Titorencu, Irina; Dekhtyar, Yuri; Jinga, Victor; Pruna, Vasile; Balaceanu, Mihai; Dinu, Mihaela; Pana, Iulian; Vendina, Viktorija; Braic, Mariana

    2016-01-01

    In the current study, we have examined the possibility to improve the biocompatibility of the (TiZrNbTaHf)C through replacement of either Ti or Ta by Si. The coatings were deposited on Si and 316L stainless steel substrates by magnetron sputtering in an Ar+CH4 mixed atmosphere and were examined for elemental composition, chemical bonds, surface topography, surface electrical charge and biocompatible characteristics. The net surface charge was evaluated at nano and macroscopic scale by measuring the electrical potential and work function, respectively. The biocompatible tests comprised determination of cell viability and cell attachment to the coated surface. The deposited coatings had C/(metal+Si) ratios close to unity, while a mixture of metallic carbide, free-carbon and oxidized species formed on the film surface. The coatings' surfaces were smooth and no influence of surface roughness on electrical charge or biocompatibility was found. The biocompatible characteristics correlated well with the electrical potential/work function, suggesting a significant role of surface charge in improving biocompatibility, particularly cell attachment to coating's surface. Replacement of either Ti or Ta by Si in the (TiZrNbTaHf)C coating led to an enhanced surface electrical charge, as well as to superior biocompatible properties, with best results for the (TiZrNbSiHf)C coating. PMID:27571361

  18. In Vitro Biocompatibility of Si Alloyed Multi-Principal Element Carbide Coatings

    Science.gov (United States)

    Vladescu, Alina; Titorencu, Irina; Dekhtyar, Yuri; Jinga, Victor; Pruna, Vasile; Balaceanu, Mihai; Dinu, Mihaela; Pana, Iulian; Vendina, Viktorija

    2016-01-01

    In the current study, we have examined the possibility to improve the biocompatibility of the (TiZrNbTaHf)C through replacement of either Ti or Ta by Si. The coatings were deposited on Si and 316L stainless steel substrates by magnetron sputtering in an Ar+CH4 mixed atmosphere and were examined for elemental composition, chemical bonds, surface topography, surface electrical charge and biocompatible characteristics. The net surface charge was evaluated at nano and macroscopic scale by measuring the electrical potential and work function, respectively. The biocompatible tests comprised determination of cell viability and cell attachment to the coated surface. The deposited coatings had C/(metal+Si) ratios close to unity, while a mixture of metallic carbide, free-carbon and oxidized species formed on the film surface. The coatings’ surfaces were smooth and no influence of surface roughness on electrical charge or biocompatibility was found. The biocompatible characteristics correlated well with the electrical potential/work function, suggesting a significant role of surface charge in improving biocompatibility, particularly cell attachment to coating's surface. Replacement of either Ti or Ta by Si in the (TiZrNbTaHf)C coating led to an enhanced surface electrical charge, as well as to superior biocompatible properties, with best results for the (TiZrNbSiHf)C coating. PMID:27571361

  19. Superparamagnetic microrobots: fabrication by two-photon polymerization and biocompatibility.

    Science.gov (United States)

    Suter, Marcel; Zhang, Li; Siringil, Erdem C; Peters, Christian; Luehmann, Tessa; Ergeneman, Olgac; Peyer, Kathrin E; Nelson, Bradley J; Hierold, Christofer

    2013-12-01

    This work presents the fabrication and controlled actuation of swimming microrobots made of a magnetic polymer composite (MPC) consisting of 11-nm-diameter magnetite (Fe3O4) nanoparticles and photocurable resin (SU-8). Two-photon polymerization (TPP) is used to fabricate the magnetic microstructures. The material properties and the cytotoxicity of the MPC with different nanoparticle concentrations are characterized. The live/dead staining tests indicate that MPC samples with varied concentrations, up to 10 vol.%, have negligible cytotoxicity after 24 h incubation. Fabrication parameters of MPC with up to 4 vol.% were investigated. We demonstrate that the helical microdevices made of 2 vol.% MPC were capable of performing corkscrew motion in water applying weak uniform rotating magnetic fields. PMID:23846247

  20. Design of Nanoparticles Loaded Acyclovir for Controlled Delivery System

    Directory of Open Access Journals (Sweden)

    Shadab Shahsavari

    2015-10-01

    Full Text Available Introduction: The aim of this research was to develop a new drug release systems based on Nanoparticles. In this study, the natural polymer chitosan was used for preparation of nanoparticles due to its unique properties, such as biocompatibility and biodegradability. Methods: The polymeric nano-drug controlled release system has been designed with experimental design D-optimal response surface methodology, for varied variables such as the concentration of acyclovir, concentration ratio of chitosan/ TPP and pH using the ionic gelation method. The nanoparticles were characterized morphologically by scanning electron microcopy (SEM, particle size analyser (DLS for determining size, zeta and PdI, Fourier Transform Infra-Red (FTIR Spectroscopy for determination of structure of nanoparticlesand thermo gravimetric analysis (TGAfor studying thermal behavior. The optimized nanoparticles were characterized. Results: The size of the particles was detected to be 132±24.3 nm; zeta potential was 32±2.87 mV; PdI of particles was 0.159±0.05; and calculated EE% was 85±4.38%. An in-vitro release study of the prepared nanoparticles illustrated that the percentage of acyclovir released from the nanoparticles was 80.17±2.45% within 48 hrs. Conclusion: The optimized nanoparticles according to SEM image, exhibited segregated and non-aggregated nanoparticles with sub-spherical smooth morphology and also the high thermal stability of acyclovir nanoparticles at temperature up to 200°C due to TGA analysis, which indicated a well-established structure of nanoparticles.

  1. Facile Synthesis, Silanization and Biodistribution of Biocompatible Quantum Dots

    OpenAIRE

    Ma, Nan; Marshall, Ann F.; Gambhir, Sanjiv S.; Rao, Jianghong

    2010-01-01

    Here we report a facile strategy to the synthesis of silica-coated quantum dots (QDs) for in vivo imaging. All the QD synthesis and silanization steps are conducted in water and methanol under mild conditions without involving any organometallic precursors and high temperature, oxygen-free environments. The as-prepared silica-coated QDs possess high quantum yields and are extremely stable in mouse serum. In addition, the silanization method developed here produces nanoparticles (NPs) with sma...

  2. Biocompatible inorganic nanocrystals for fluorescence and CT imaging

    OpenAIRE

    Hezinger, Anna

    2010-01-01

    The enhancement of existing and development of new nanoparticular probes is a promising field of research, emanating from the increasing demand on nanoparticular contrast agents for luminescence and CT imaging. The first developed system is an ultra small inorganic semiconductor based nanoparticle with unique optical properties, ranging from size tunable emission to very high photostability. The second investigated nanoparticulate system is a lot less prominent on the field of molecular imagi...

  3. Preparation and characterization of biofunctionalized chitosan/Fe3O4 magnetic nanoparticles for application in liver magnetic resonance imaging

    Science.gov (United States)

    Song, Xiaoli; Luo, Xiadan; Zhang, Qingqing; Zhu, Aiping; Ji, Lijun; Yan, Caifeng

    2015-08-01

    Biofunctionalized chitosan@Fe3O4 nanoparticles are synthesized by combining Fe3O4 and CS chemically modified with PEG and lactobionic acid in one step. The biofunctionalized nanoparticles are characterized by TEM, X-ray, DLS, zeta-potential and magnetic measurements. The in vitro and in vivo behaviors of the biofunctionalized nanoparticles, especially, the cytotoxicity, the protein resistance, metabolism and iron toxicity are assessed. The functional groups, PEG enable the nanoparticles more biocompatible and the lactobionic acid groups enable liver targeting. The potential applications of the nanoparticles in liver magnetic resonance imaging are confirmed. The results demonstrated that the nanoparticles are suspension stability, non-cytotoxicity, non-tissue toxicity and sensitive in liver magnetic resonance imaging, representing potential tools for applications in the biomedical field.

  4. Study on the α-cyclodextrin/poly(ethylene glycol) self-assembly supramolecular nanoparticles for drug delivery

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This paper reports the synthesis and drug delivery properties of a novel supramolecular nanoparticle.α-Cyclodextrins(α-CD) were threaded on cinnamic acid modified poly(ethylene glycol) to form inclusion complex nanoparticles by supramolecular self-assemble.The anti-tumor drug doxorubicin was loaded in the nanoparticles and released in vitro to study the drug release behavior and the anti-tumor effects.The structure and morphology of the nanoparticles were characterized by nuclear magnetic resonance,X-ray diffraction,ultraviolet absorbance,dynamic laser scattering,scanning electronic microscopy,transmission electron microscopy and atom force microscopy.The distribution of the drug loaded nanoparticles in cells and the anti-tumor effects were studied by confocal laser microscopy.The results demonstrate that the supramolecular nanoparticle is biocompatible and it is a promising carrier for drug delivery systems.

  5. Field emission scanning electron microscopy (FE-SEM) as an approach for nanoparticle detection inside cells.

    Science.gov (United States)

    Havrdova, M; Polakova, K; Skopalik, J; Vujtek, M; Mokdad, A; Homolkova, M; Tucek, J; Nebesarova, J; Zboril, R

    2014-12-01

    When developing new nanoparticles for bio-applications, it is important to fully characterize the nanoparticle's behavior in biological systems. The most common techniques employed for mapping nanoparticles inside cells include transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). These techniques entail passing an electron beam through a thin specimen. STEM or TEM imaging is often used for the detection of nanoparticles inside cellular organelles. However, lengthy sample preparation is required (i.e., fixation, dehydration, drying, resin embedding, and cutting). In the present work, a new matrix (FTO glass) for biological samples was used and characterized by field emission scanning electron microscopy (FE-SEM) to generate images comparable to those obtained by TEM. Using FE-SEM, nanoparticle images were acquired inside endo/lysosomes without disruption of the cellular shape. Furthermore, the initial steps of nanoparticle incorporation into the cells were captured. In addition, the conductive FTO glass endowed the sample with high stability under the required accelerating voltage. Owing to these features of the sample, further analyses could be performed (material contrast and energy-dispersive X-ray spectroscopy (EDS)), which confirmed the presence of nanoparticles inside the cells. The results showed that FE-SEM can enable detailed characterization of nanoparticles in endosomes without the need for contrast staining or metal coating of the sample. Images showing the intracellular distribution of nanoparticles together with cellular morphology can give important information on the biocompatibility and demonstrate the potential of nanoparticle utilization in medicine.

  6. Gold-Pluronic core-shell nanoparticles: synthesis, characterization and biological evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Timea; Boca, Sanda [Babes-Bolyai University, Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute on Bio-Nano-Sciences and Faculty of Physics (Romania); Biro, Dominic [Sapientia University, Department of Mechanical Engineering, Faculty of Technical and Human Sciences (Romania); Baldeck, Patrice [Universite Joseph Fourier and CNRS, Laboratoire Interdisciplinaire de Physique, UMR 5588, CNRS (France); Astilean, Simion, E-mail: simion.astilean@phys.ubbcluj.ro [Babes-Bolyai University, Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute on Bio-Nano-Sciences and Faculty of Physics (Romania)

    2013-04-15

    This study presents the synthesis of gold-Pluronic core-shell nanoparticles by a two-step method and investigates their biological impact on cancer cells, specifically nanoparticle internalization and cytotoxicity. Uniform, 9-10-nm-sized, hydrophobic gold nanoparticles were synthesized in organic phase by reducing gold salt with oleylamine, after which oleylamine-protected gold nanoparticles were phase-transferred into aqueous medium using Pluronic F127 block copolymer, resulting in gold-Pluronic core-shell nanoparticles with a mean hydrodynamic diameter of {approx}35 nm. The formation and phase-transfer of gold nanoparticles were analyzed by UV-Vis absorption spectroscopy, transmission electron microscopy, and dynamic light scattering. The obtained gold-Pluronic core-shell nanoparticles proved to be highly stable in salted solution. Cytotoxicity tests showed no modification of cellular viability in the presence of properly purified particles. Furthermore, dark-field cellular imaging demonstrated that gold-Pluronic nanoparticles were able to be efficiently uptaken by cells, being internalized through nonspecific endocytosis. The high stability, proven biocompatibility, and imaging properties of gold-Pluronic core-shell nanoparticles hold promise for relevant intracellular applications, with such a design providing the feasibility to combine all multiple functionalities in one nanoparticle for simultaneous detection and imaging.

  7. Rapid pharmacokinetic and biodistribution studies using cholorotoxin-conjugated iron oxide nanoparticles: a novel non-radioactive method.

    Directory of Open Access Journals (Sweden)

    Michelle Jeung-Eun Lee

    Full Text Available BACKGROUND: Recent advances in nanotechnology have led to the development of biocompatible nanoparticles for in vivo molecular imaging and targeted therapy. Many nanoparticles have undesirable tissue distribution or unacceptably low serum half-lives. Pharmacokinetic (PK and biodistribution studies can help inform decisions determining particle size, coatings, or other features early in nanoparticle development. Unfortunately, these studies are rarely done in a timely fashion because many nanotechnology labs lack the resources and expertise to synthesize radioactive nanoparticles and evaluate them in mice. METHODOLOGY/PRINCIPAL FINDINGS: To address this problem, we developed an economical, radioactivity-free method for assessing serum half-life and tissue distribution of nanoparticles in mice. Iron oxide nanoparticles coated with chitosan and polyethylene glycol that utilize chlorotoxin as a targeting molecule have a serum half-life of 7-8 hours and the particles remain stable for extended periods of time in physiologic fluids and in vivo. Nanoparticles preferentially distribute to spleen and liver, presumably due to reticuloendothelial uptake. Other organs have very low levels of nanoparticles, which is ideal for imaging most cancers in the future. No acute toxicity was attributed to the nanoparticles. CONCLUSIONS/SIGNIFICANCE: We report here a simple near-infrared fluorescence based methodology to assess PK properties of nanoparticles in order to integrate pharmacokinetic data into early nanoparticle design and synthesis. The nanoparticles tested demonstrate properties that are excellent for future clinical imaging strategies and potentially suitable for targeted therapy.

  8. Iron nanoparticles from blood coated with collagen as a matrix for synthesis of nanohydroxyapatite

    Indian Academy of Sciences (India)

    M Chamundeeswari; B Santhosh Kumar; T Muthukumar; L Muthuraman; K Purna Sai; T P Sastry

    2013-12-01

    A simple wet precipitation technique was used to prepare nanobiocomposite containing iron nanoparticles coated with collagen. This nanobiocomposite was used as matrix for the synthesis of nanohydroxyapatite. The physicochemical characteristic studies of the nanohydroxyapatite thus formed were carried out using fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energydispersive X-ray spectroscopy and X-ray diffraction technique to confirm the formation of hydroxyapatite on iron nanoparticle–collagen complex. The results of the above studies supported the formation of iron nanoparticle–collagen–hydroxyapatite composite. The biological studies such as biocompatibility and hemocompatibility were carried out for nanohydroxyapatite using different cell lines and blood sample. The results of biocompatibility and hemolytic assay revealed that the prepared nanobiocomposite was 100 % biocompatible and hemocompatible. This nanobiocomposite may be used for biomedical application such as injectables for targeted delivery and as scaffold for tissue engineering.

  9. Biocompatibility evaluation of tissue-engineered decellularized scaffolds for biomedical application.

    Science.gov (United States)

    Hussein, Kamal Hany; Park, Kyung-Mee; Kang, Kyung-Sun; Woo, Heung-Myong

    2016-10-01

    Biomaterials based on seeding of cells on decellularized scaffolds have gained increasing interest in the last few years and suggested to serve as an alternative approach to bioengineer artificial organs and tissues for transplantation. The reaction of the host toward the decellularized scaffold and transplanted cells depends on the biocompatibility of the construct. Before proceeding to the clinical application step of decellularized scaffolds, it is greatly important to apply a number of biocompatibility tests in vitro and in vivo. This review describes the different methodology involved in cytotoxicity, pathogenicity, immunogenicity and biodegradability testing for evaluating the biocompatibility of various decellularized matrices obtained from human or animals. PMID:27287176

  10. Synthesis of Biocompatible Nanoparticulate Coordination Polymers for Diagnostic and Therapeutic Applications

    Science.gov (United States)

    Kandanapitiye, Murthi S.

    -ray computed tomography is capable of delineating the 3-D images of soft tissues with superb quality. The variation of X-ray attenuation from one tissue to another is used to generate the well spatial resolved superb quality images. Exogenous radiopaque agents are necessary for the superb visualization of different types of soft tissues. Heavy metals with high atomic number are better suited for biomedical applications to enhance the image contrast due to their high mass attenuation coefficient. Bismuth (Z- 83) is the nonradioactive, heaviest, nontoxic element available among the other closest neighbors (Hg, Tl, Pb and Po) of the periodic table. We have set out to search for compounds that are hydrolytically stable, more efficient and more amenable in terms of biocompatibility. Moreover this new discovery can significantly reduce the average radiation dose in one CT scan. We have discovered a simple one-step aqueous solution route for preparing biocompatible and ultra-small bismuth oxyiodide BiOI nanoparticles and investigated their potential application as an efficient CT contrast agent. Our ultra-small monodisperse BiOI NPs have excellent water dispersability, thermodynamic stability, kinetic inertness, high biocompatibility and superior attenuation power, suggesting their potential as an organ-specific CT contrast agent that may fill the gap left by the other nanoparticulate and iodine-based CT contrasting agents. The chapter 6 of this dissertation discusses synthesis and characterization of novel nanoparticulate therapeutics and theranostics. D-penicillamine has the highest efficacy, and hence is currently the most widely used drug for WD across the world. We have prepared the D-PEN-conjugated Au NPs of the average size of 16 [special character omited] 2 nm with superb water dispersability, and examined the kinetics and selectivity of copper binding of such NPs in aqueous solution. We also studied the cellular uptake, cytotoxicity and intracellular copper removal of these

  11. PLGA nanoparticles from nano-emulsion templating as imaging agents: Versatile technology to obtain nanoparticles loaded with fluorescent dyes.

    Science.gov (United States)

    Fornaguera, C; Feiner-Gracia, N; Calderó, G; García-Celma, M J; Solans, C

    2016-11-01

    The interest in polymeric nanoparticles as imaging systems for biomedical applications has increased notably in the last decades. In this work, PLGA nanoparticles, prepared from nano-emulsion templating, have been used to prepare novel fluorescent imaging agents. Two model fluorescent dyes were chosen and dissolved in the oil phase of the nano-emulsions together with PLGA. Nano-emulsions were prepared by the phase inversion composition (PIC) low-energy method. Fluorescent dye-loaded nanoparticles were obtained by solvent evaporation of nano-emulsion templates. PLGA nanoparticles loaded with the fluorescent dyes showed hydrodynamic radii lower than 40nm; markedly lower than those reported in previous studies. The small nanoparticle size was attributed to the nano-emulsification strategy used. PLGA nanoparticles showed negative surface charge and enough stability to be used for biomedical imaging purposes. Encapsulation efficiencies were higher than 99%, which was also attributed to the nano-emulsification approach as well as to the low solubility of the dyes in the aqueous component. Release kinetics of both fluorescent dyes from the nanoparticle dispersions was pH-independent and sustained. These results indicate that the dyes could remain encapsulated enough time to reach any organ and that the decrease of the pH produced during cell internalization by the endocytic route would not affect their release. Therefore, it can be assumed that these nanoparticles are appropriate as systemic imaging agents. In addition, in vitro toxicity tests showed that nanoparticles are non-cytotoxic. Consequently, it can be concluded that the preparation of PLGA nanoparticles from nano-emulsion templating represents a very versatile technology that enables obtaining biocompatible, biodegradable and safe imaging agents suitable for biomedical purposes.

  12. Enhanced photodynamic therapy efficacy of methylene blue-loaded calcium phosphate nanoparticles.

    Science.gov (United States)

    Seong, Da-Young; Kim, Young-Jin

    2015-05-01

    Although methylene blue (MB) is the most inexpensive photosensitizer with promising applications in the photodynamic therapy (PDT) for its high quantum yield of singlet oxygen generation, the clinical use of MB has been limited by its rapid enzymatic reduction in the biological environment. To enhance PDT efficacy of MB by preventing the enzymatic reduction, we have developed a new mineralization method to produce highly biocompatible MB-loaded calcium phosphate (CaP-MB) nanoparticles in the presence of polymer templates. The resulting CaP-MB nanoparticles exhibited spherical shape with a size of under 50 nm. Fourier transform infrared (FT-IR) and zeta-potential analyses confirmed the insertion of MB into the CaP-MB nanoparticles. The encapsulation of MB in CaP nanoparticles could effectively protect MB from the enzymatic reduction. In addition, the CaP-MB nanoparticles exhibited a good biocompatibility in the dark condition and significantly enhanced PDT efficacy due to apoptotic cell death against human breast cancer cells as compared with free MB, implying that CaP-MB nanoparticle system might be potentially applicable in PDT.

  13. Tunable, biodegradable gold nanoparticles as contrast agents for computed tomography and photoacoustic imaging.

    Science.gov (United States)

    Cheheltani, Rabee; Ezzibdeh, Rami M; Chhour, Peter; Pulaparthi, Kumidini; Kim, Johoon; Jurcova, Martina; Hsu, Jessica C; Blundell, Cassidy; Litt, Harold I; Ferrari, Victor A; Allcock, Harry R; Sehgal, Chandra M; Cormode, David P

    2016-09-01

    Gold nanoparticles (AuNP) have been proposed for many applications in medicine. Although large AuNP (>5.5 nm) are desirable for their longer blood circulation and accumulation in diseased tissues, small AuNP (nanoparticles (Au-PCPP) can perform their function as contrast agents, then subsequently break down into harmless byproducts and release the AuNP for swift excretion. Homogeneous Au-PCPP were synthesized using a microfluidic device. The size of the Au-PCPP can be controlled by the amount of polyethylene glycol-polylysine (PEG-PLL) block co-polymer in the formulation. Synthesis of Au-PCPP nanoparticles and encapsulation of AuNP in PCPP were evaluated using transmission electron microscopy and their biocompatibility and biodegradability confirmed in vitro. The Au-PCPP nanoparticles were found to produce strong computed tomography contrast. The UV-Vis absorption peak of Au-PCPP can be tuned into the near infrared region via inclusion of varying amounts of AuNP and controlling the nanoparticle size. In vitro and in vivo experiments demonstrated the potential of Au-PCPP as contrast agents for photoacoustic imaging. Therefore, Au-PCPP nanoparticles have high potency as contrast agents for two imaging modalities, as well as being biocompatible and biodegradable, and thus represent a platform with potential for translation into the clinic. PMID:27322961

  14. A facile approach for cupric ion detection in aqueous media using polyethyleneimine/PMMA core-shell fluorescent nanoparticles

    Science.gov (United States)

    Chen, Jian; Zeng, Fang; Wu, Shuizhu; Su, Junhua; Zhao, Jianqing; Tong, Zhen

    2009-09-01

    A facile approach was developed to produce a dye-doped core-shell nanoparticle chemosensor for detecting Cu2+ in aqueous media. The core-shell nanoparticle sensor was prepared by a one-step emulsifier-free polymerization, followed by the doping of the fluorescent dye Nile red (9-diethylamino- 5H-benzo[alpha] phenoxazine-5-one, NR) into the particles. For the nanoparticles, the hydrophilic polyethyleneimine (PEI) chain segments serve as the shell and the hydrophobic polymethyl methacrylate (PMMA) constitutes the core of the nanoparticles. The non-toxic and biocompatible PEI chain segments on the nanoparticle surface exhibit a high affinity for Cu2+ ions in aqueous media, and the quenching of the NR fluorescence is observed upon binding of Cu2+ ions. This makes the core-shell nanoparticle system a water-dispersible chemosensor for Cu2+ ion detection. The quenching of fluorescence arises through intraparticle energy transfer (FRET) from the dye in the hydrophobic PMMA core to the Cu2+/PEI complexes on the nanoparticle surface. The energy transfer efficiency for PEI/PMMA particles with different diameters was determined, and it is found that the smaller nanoparticle sample exhibits higher quenching efficiency, and the limit for Cu2+ detection is 1 µM for a nanoparticle sample with a diameter of ~30 nm. The response of the fluorescent nanoparticle towards different metal ions was investigated and the nanoparticle chemosensor displays high selectivity and antidisturbance for the Cu2+ ion among the metal ions examined (Na+, K+, Mg2+, Ca2+, Zn2+, Hg2+, Mn2+, Fe2+, Ni2+, Co2+ and Pb2+). This emulsifier-free, biocompatible and sensitive fluorescent nanoparticle sensor may find applications in cupric ion detection in the biological and environmental areas.

  15. Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe3O4 nanocomposites as a promising, nontoxic system for biomedical applications

    Directory of Open Access Journals (Sweden)

    Hanieh Shirazi

    2015-08-01

    Full Text Available The unique properties and applications of iron oxide and Au nanoparticles have motivated researchers to synthesize and optimize a combined nanocomposite containing both. By using various polymers such as chitosan, some of the problems of classic core–shell structures (such as reduced saturation magnetization and thick coating have been overcome. In the present study, chitosan and one of its well-known derivatives, N-trimethylchitosan (TMC, were applied to construct three-layer nanocomposites in an Au/polymer/Fe3O4 system. It was demonstrated that replacement of chitosan with TMC reasonably improved the properties of the final nanocomposites including their size, magnetic behavior and thermal stability. Moreover, the results of the MTT assay showed no significant cytotoxicity effect when the Au/TMC/Fe3O4 nanocomposites were applied in vitro. These TMC-containing magnetic nanoparticles are well-coated by Au nanoparticles and have good biocompatibility and can thus play the role of a platform or a label in various fields of application, especially the biomedical sciences and biosensors.

  16. Biocompatibility of new Ti-Nb-Ta base alloys.

    Science.gov (United States)

    Hussein, Abdelrahman H; Gepreel, Mohamed A-H; Gouda, Mohamed K; Hefnawy, Ahmad M; Kandil, Sherif H

    2016-04-01

    β-type titanium alloys are promising materials in the field of medical implants. The effect of β-phase stability on the mechanical properties, corrosion resistance and cytotoxicity of a newly designed β-type (Ti77Nb17Ta6) biocompatible alloys are studied. The β-phase stability was controlled by the addition of small quantities of Fe and O. X-ray diffraction and microstructural analysis showed that the addition of O and Fe stabilized the β-phase in the treated solution condition. The strength and hardness have increased with the increase in β-phase stability while ductility and Young's modulus have decreased. The potentio-dynamic polarization tests showed that the corrosion resistance of the new alloys is better than Ti-6Al-4V alloy by at least ten times. Neutral red uptake assay cytotoxicity test showed cell viability of at least 95%. The new alloys are promising candidates for biomedical applications due to their high mechanical properties, corrosion resistance, and reduced cytotoxicity. PMID:26838885

  17. Effect of plasma surface modification on the biocompatibility of UHMWPE

    Energy Technology Data Exchange (ETDEWEB)

    Kaklamani, G; Chen, J; Dong, H; Stamboulis, A [School of Metallurgy and Materials, College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Mehrban, N; Bowen, J; Grover, L, E-mail: a.stamboulis@bham.ac.u [School of Chemical Engineering, College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2010-10-01

    In this paper active screen plasma nitriding (ASPN) is used to chemically modify the surface of UHMWPE. This is an unexplored and new area of research. ASPN allows the homogeneous treatment of any shape or surface at low temperature; therefore, it was thought that ASPN would be an effective technique to modify organic polymer surfaces. ASPN experiments were carried out at 120 {sup 0}C using a dc plasma nitriding unit with a 25% N{sub 2} and 75% H{sub 2} atmosphere at 2.5 mbar of pressure. UHMWPE samples treated for different time periods were characterized by nanoindentation, FTIR, XPS, interferometry and SEM. A 3T3 fibroblast cell line was used for in vitro cell culture experiments. Nanoindentation of UHMWPE showed that hardness and elastic modulus increased with ASPN treatment compared to the untreated material. FTIR spectra did not show significant differences between the untreated and treated samples; however, some changes were observed at 30 min of treatment in the range of 1500-1700 cm{sup -1} associated mainly with the presence of N-H groups. XPS studies showed that nitrogen was present on the surface and its amount increased with treatment time. Interferometry showed that no significant changes were observed on the surfaces after the treatment. Finally, cell culture experiments and SEM showed that fibroblasts attached and proliferated to a greater extent on the plasma-treated surfaces leading to the conclusion that ASPN surface treatment can potentially significantly improve the biocompatibility behaviour of polymeric materials.

  18. Fabrication and Biocompatibility of Electrospun Silk Biocomposites

    Directory of Open Access Journals (Sweden)

    Ick-Soo Kim

    2011-10-01

    Full Text Available Silk fibroin has attracted great interest in tissue engineering because of its outstanding biocompatibility, biodegradability and minimal inflammatory reaction. In this study, two kinds of biocomposites based on regenerated silk fibroin are fabricated by electrospinning and post-treatment processes, respectively. Firstly, regenerated silk fibroin/tetramethoxysilane (TMOS hybrid nanofibers with high hydrophilicity are prepared, which is superior for fibroblast attachment. The electrospinning process causes adjacent fibers to ‘weld’ at contact points, which can be proved by scanning electron microscope (SEM. The water contact angle of silk/tetramethoxysilane (TMOS composites shows a sharper decrease than pure regenerated silk fibroin nanofiber, which has a great effect on the early stage of cell attachment behavior. Secondly, a novel tissue engineering scaffold material based on electrospun silk fibroin/nano-hydroxyapatite (nHA biocomposites is prepared by means of an effective calcium and phosphate (Ca–P alternate soaking method. nHA is successfully produced on regenerated silk fibroin nanofiber within several min without any pre-treatments. The osteoblastic activities of this novel nanofibrous biocomposites are also investigated by employing osteoblastic-like MC3T3-E1 cell line. The cell functionality such as alkaline phosphatase (ALP activity is ameliorated on mineralized silk nanofibers. All these results indicate that this silk/nHA biocomposite scaffold material may be a promising biomaterial for bone tissue engineering.

  19. Viability of biocompatible and biodegradable seeds production with incorporated radionuclides

    International Nuclear Information System (INIS)

    The present work aims the development of radioactive seeds, biocompatible and biodegradable, with the objective of adding options in the cancer treatment. The work focus on the production of seeds biodegradable that incorporate radioisotopes with half life inferior than the degradation time of the material. The idea of producing devices with biodegradable materials impregnated with radioisotopes of short half life will offer new possibilities in the cancer treatment, since they can be used following the same procedures of the permanent interstitial brachytherapy, but using degradable materials compatible with the physiological environment. It will be discussed in particular the possible application of these seeds in the treatment of prostate cancer. A review of the subject and a preliminary evaluation of the viability of production of the seeds will be presented. The method of production of the seeds is based on the incorporation of Iodine and Samarium in glass matrixes obtained by sol-gel processing. X-ray fluorescence was done in the samples produced and the incorporation of Iodine and Samarium atoms was confirmed. (author)

  20. Metallic ion release from biocompatible cobalt-based alloy

    Directory of Open Access Journals (Sweden)

    Dimić Ivana D.

    2014-01-01

    Full Text Available Metallic biomaterials, which are mainly used for the damaged hard tissue replacements, are materials with high strength, excellent toughness and good wear resistance. The disadvantages of metals as implant materials are their susceptibility to corrosion, the elastic modulus mismatch between metals and human hard tissues, relatively high density and metallic ion release which can cause serious health problems. The aim of this study was to examine metallic ion release from Co-Cr-Mo alloy in artificial saliva. In that purpose, alloy samples were immersed into artificial saliva with different pH values (4.0, 5.5 and 7.5. After a certain immersion period (1, 3 and 6 weeks the concentrations of released ions were determined using Inductively Coupled Plasma - Mass Spectrophotometer (ICP-MS. The research findings were used in order to define the dependence between the concentration of released metallic ions, artificial saliva pH values and immersion time. The determined released metallic ions concentrations were compared with literature data in order to describe and better understand the phenomenon of metallic ion release from the biocompatible cobalt-based alloy. [Projekat Ministarstva nauke Republike Srbije, br. III 46010 i br. ON 174004