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Sample records for delivery applications synthesis

  1. Biodegradable PLGA-b-PEG polymeric nanoparticles: synthesis, properties, and nanomedical applications as drug delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Locatelli, Erica; Comes Franchini, Mauro, E-mail: mauro.comesfranchini@unibo.it [University of Bologna, Dipartimento di Chimica Industriale Toso Montanari (Italy)

    2012-12-15

    During the past decades many synthetic polymers have been studied for nanomedicine applications and in particular as drug delivery systems. For this purpose, polymers must be non-toxic, biodegradable, and biocompatible. Polylactic-co-glycolic acid (PLGA) is one of the most studied polymers due to its complete biodegradability and ability to self-assemble into nanometric micelles that are able to entrap small molecules like drugs and to release them into body in a time-dependent manner. Despite fine qualities, using PLGA polymeric nanoparticles for in vivo applications still remains an open challenge due to many factors such as poor stability in water, big diameter (150-200 nm), and the removal of these nanocarriers from the blood stream by the liver and spleen thus reducing the concentration of drugs drastically in tumor tissue. Polyethylene glycol (PEG) is the most used polymers for drug delivery applications and the first PEGylated product is already on the market for over 20 years. This is due to its stealth behavior that inhibits the fast recognition by the immune system (opsonization) and generally leads to a reduced blood clearance of nanocarriers increasing blood circulation time. Furthermore, PEG is hydrophilic and able to stabilize nanoparticles by steric and not ionic effects especially in water. PLGA-PEG block copolymer is an emergent system because it can be easily synthesized and it possesses all good qualities of PLGA and also PEG capability so in the last decade it arose as one of the most promising systems for nanoparticles formation, drug loading, and in vivo drug delivery applications. This review will discuss briefly on PLGA-b-PEG synthesis and physicochemical properties, together with its improved qualities with respect to the single PLGA and PEG polymers. Moreover, we will focus on but in particular will treat nanoparticles formation and uses as new drug delivery system for nanomedical applications.

  2. Synthesis and characterization of novel dual-responsive nanogels and their application as drug delivery systems

    Science.gov (United States)

    Peng, Jinrong; Qi, Tingting; Liao, Jinfeng; Fan, Min; Luo, Feng; Li, He; Qian, Zhiyong

    2012-03-01

    In this study, a temperature/pH dual-response nanogel based on NIPAm, MAA, and PEGMA was synthesized via emulsion polymerization and characterized by 1H-NMR, FT-IR, TEM and DLS. By introducing a novel initiator, through which PEG-AIBN-PEG was synthesized, it was revealed that the PEG segments from PEG-AIBN-PEG with a dosage of initiator had a significant influence over the macro-state and stability of the nanogels. In order to optimize the feeding prescription for better application as a drug delivery system, the effect of the co-monomer contents on the response to stimuli (temperature and pH value) and cytotoxicity of the nanogels has been studied in detail. The results demonstrated that the responsiveness, reversibility and volume phase transition critical value of the nanogels could be controlled by adjusting the feeding ratio of the co-monomers in the synthesis process. MTT assay results revealed that nanogels with appropriate compositions showed good biocompatibility and relatively low toxicity. Most importantly, by studying the drug loading behavior, it was found that the dimensions of the drug molecules had a considerable influence on the drug loading efficiency and loading capacity of the nanogels, and that the mechanism by which drug molecule sizes influence the drug loading behavior of nanogels needs further investigation. The results indicated that such PNMP nanogels might have potential applications in drug delivery and other medical applications, but that the drug loading mechanism must be further developed.

  3. Advances in the synthesis and application of nanoparticles for drug delivery.

    Science.gov (United States)

    Park, Wooram; Na, Kun

    2015-01-01

    The continuous development of drug delivery systems (DDSs) has been extensively researched by the need to maximize therapeutic efficacy while minimizing undesirable side effects. Nanoparticle technology was recently shown to hold great promise for drug delivery applications in nanomedicine due to its beneficial properties, such as better encapsulation, bioavailability, control release, and lower toxic effect. Despite the great progress in nanomedicine, there remain many limitations for clinical application. To overcome these limitations, advanced nanoparticles for drug delivery have been developed to enable the spatially and temporally controlled release of drugs in response to specific stimuli at disease sites. Furthermore, the controlled self-assembly of organic and inorganic materials may enable their use in theranostic applications. This review presents an overview of a recent advanced nanoparticulate system that can be used as a potential drug delivery carrier and focuses on the potential applications of nanoparticles in various biomedical fields for human health care. © 2015 Wiley Periodicals, Inc.

  4. Photo-synthesis of protein-based nanoparticles and the application in drug delivery

    International Nuclear Information System (INIS)

    Xie, Jinbing; Wang, Hongyang; Cao, Yi; Qin, Meng; Wang, Wei

    2015-01-01

    Recently, protein-based nanoparticles as drug delivery systems have attracted great interests due to the excellent behavior of high biocompatibility and biodegradability, and low toxicity. However, the synthesis techniques are generally costly, chemical reagents introduced, and especially present difficulties in producing homogeneous monodispersed nanoparticles. Here, we introduce a novel physical method to synthesize protein nanoparticles which can be accomplished under physiological condition only through ultraviolet (UV) illumination. By accurately adjusting the intensity and illumination time of UV light, disulfide bonds in proteins can be selectively reduced and the subsequent self-assembly process can be well controlled. Importantly, the co-assembly can also be dominated when the proteins mixed with either anti-cancer drugs, siRNA, or active targeting molecules. Both in vitro and in vivo experiments indicate that our synthesized protein–drug nanoparticles (drug-loading content and encapsulation efficiency being ca. 8.2% and 70%, respectively) not only possess the capability of traditional drug delivery systems (DDS), but also have a greater drug delivery efficiency to the tumor sites and a better inhibition of tumor growth (only 35% of volume comparing to the natural growing state), indicating it being a novel drug delivery system in tumor therapy

  5. Synthesis of an amphiphilic dendrimer-like block copolymer and its application on drug delivery

    KAUST Repository

    Wang, Shuaipeng; Song, Xiaowan; Feng, Xiaoshuang; Chen, Peng; Qian, Jiasheng; Xia, Ru; Miao, Jibin

    2014-01-01

    . The application on drug delivery of dendrimer-like diblock copolymer PEEGE-G2-b-PEO(OH)12 using DOX as a model drug was also studied. The drug loading content and encapsulation efficiency were found at 13.07% and 45.75%, respectively. In vitro release experiment

  6. Synthesis of mesoporous silica nanoparticles by sol–gel as nanocontainer for future drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, N.I.; Gonzalez, Z.; Ferrari, B.; Castro, Y.

    2017-07-01

    Development of mesoporous silica nanoparticles as carriers for drug delivery systems has increased exponentially during the last decade. The present work is focused on the synthesis of silica carriers by sol–gel from tetraethyl orthosilicate (TEOS) as precursor of silica and cetyltrimethylammonium bromide (CTAB) as pore generating agent. The synthesis conditions were modified varying the molar ratio of water/TEOS, NH3/TEOS and amount of CTAB. The silica particles were characterized by scan electron microscopy techniques (FESEM), high resolution transmission electron microscopy (HR-TEM), N2 adsorption–desorption isotherms, Zeta-potential and Dynamic Light Scattering (DLS). The results show that the specific surface area and the porosity of silica particles were strongly affected by the addition of CTAB and the amount of H2O. The dispersion and stability of silica mesoporous particles is achieved in spite of the high surface reactivity. The synthesis formulation affects considerably to the particle morphology, which changes from spheres to rods when the molar ratio of H2O increases. A maximum specific surface area of 1480m2/g was obtained with pore sizes ranging 2.5–2.8nm. (Author)

  7. Recent progress in the synthesis of poly(organo)phosphazenes and their applications in tissue engineering and drug delivery

    Science.gov (United States)

    Khan, R. U.; Wang, L.; Yu, H.; Zain-ul-Abdin; Akram, M.; Wu, J.; Haroon, M.; Ullah, R. S.; Deng, Zh; Xia, X.

    2018-02-01

    It is a highly desirable goal of researchers to develop effective biomaterials with minimum recovery time and affordable treatment expense for tissue engineering and drug delivery. In this scenario, numerous synthetic and natural polymers have been used. Among those synthetic polymers, polyorganophosphazenes (POPs) have got much attention as highly promising candidates for applications in tissue engineering and drug delivery. Polyorganophosphazenes are hybrid polymers containing inorganic backbone consisting of alternating nitrogen and phosphorus atoms with two organic side groups. POPs possess a wide range of unique properties, i.e., synthetic flexibility, biocompatibility, osteocompatibility, osteoinductivity, sustainability and degradability into harmless end products with predictable degradation rate and adjustable mechanical strength. Moreover, their tunable hydrophilic/hydrophobic and stimuli responsive properties add extra points to their use in biomedical applications. In addition, their various polymeric forms, i.e., microspheres, nano/microfibres, micelles, membranes, polymersomes, hydrogels and nano-conjugate linear polymers provide different carriers to efficiently deliver various hydrophilic/hydrophobic therapeutic agents both in vitro and in vivo. This review focuses on the most recent progress that has been made in the synthesis and applications of POPs in tissue engineering and their different polymeric forms used for drug delivery. Moreover, we have also summarized the effect of different side groups on the overall efficiency of POPs. The bibliography includes 239 references.

  8. Synthesis of click-reactive HPMA copolymers using RAFT polymerization for drug delivery applications

    DEFF Research Database (Denmark)

    Ebbesen, Morten F; Schaffert, D.H.; Crowley, Michael L

    2013-01-01

    This study describes a versatile strategy combining reversible addition fragmentation transfer (RAFT) polymerization and click chemistry to synthesize well-defined, reactive copolymers of N-(2-hydroxypropyl)methacrylamide (HPMA) for drug delivery applications. A novel azide containing monomer N-(3......-azidopropyl)methacrylamide (AzMA) was synthesized and copolymerized with HPMA using RAFT polymerization to provide p(HPMA-co-AzMA) copolymers with high control of molecular weight (∼10–54 kDa) and polydispersity (≤1.06). The utility of the side-chain azide functionality by Cu(I)-catalyzed azide...

  9. Synthesis and evaluation of functional alginate hydrogels based on click chemistry for drug delivery applications.

    Science.gov (United States)

    García-Astrain, Clara; Avérous, Luc

    2018-06-15

    Environment-sensitive alginate-based hydrogels for drug delivery applications are receiving increasing attention. However, most work in this field involves traditional cross-linking strategies which led to hydrogels with poor long-term stability. Herein, a series of chemically cross-linked alginate hydrogels was synthesized via click chemistry using Diels-Alder reaction by reacting furan-modified alginate and bifunctional cross-linkers. Alginate was successfully functionalized with furfurylamine. Then, 3D architectures were synthesized with water-soluble bismaleimides. Different substitution degrees were achieved in order to study the effect of alginate modification and the cross-linking extent over the behaviour of the hydrogels. The ensuing hydrogels were analysed in terms of microstructure, swelling, structure modification and rheological behaviour. The materials response to external stimuli such as pH was also investigated, revealing a pulsatile behaviour in a large pH range (1-13) and a clear pH-dependent swelling. Finally, vanillin release studies were conducted to demonstrate the potential of these biobased materials for drug delivery applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Synthesis of an amphiphilic dendrimer-like block copolymer and its application on drug delivery

    KAUST Repository

    Wang, Shuaipeng

    2014-10-27

    Dendrimer-like amphiphilic copolymer is a kind of three-dimensional spherical structure polymer. An amphiphilic dendrimer-like diblock copolymer, PEEGE-G2-b-PEO(OH)12, constituted of a hydrophobic poly(ethoxyethyl glycidol ether) inner core and a hydrophilic poly(ethylene oxide) outer layer, has been successfully synthesized by the living anionic ring-opening polymerization method. The intermediates and targeted products were characterized with 1H NMR spectroscopy and gel permeation chromatography. The application on drug delivery of dendrimer-like diblock copolymer PEEGE-G2-b-PEO(OH)12 using DOX as a model drug was also studied. The drug loading content and encapsulation efficiency were found at 13.07% and 45.75%, respectively. In vitro release experiment results indicated that the drug-loaded micelles exhibited a sustained release behavior under acidic media.

  11. Synthesis and characterization of pharmaceutical surfactant templated mesoporous silica: Its application to controlled delivery of duloxetine

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Ganesh; Pushparaj, Hemalatha; Peng, Mei Mei; Muthiahpillai, Palanichamy [Department of Chemical Engineering, Hanseo University, Seosan-si 356 706 (Korea, Republic of); Udhumansha, Ubaidulla [Department of Chemical Engineering, Hanseo University, Seosan-si 356 706 (Korea, Republic of); Department of Pharmaceutics, C.L. Baid Metha College of Pharmacy, Chennai (India); Jang, Hyun Tae, E-mail: htjang@hanseo.ac.kr [Department of Chemical Engineering, Hanseo University, Seosan-si 356 706 (Korea, Republic of)

    2014-03-01

    Graphical abstract: - Highlights: • Usefulness of dual pharmaceutical surfactants in silica synthesis was evaluated. • Effects of concentration of secondary template (Tween-40) were studied. • Effects of fixed solvothermal condition on mesostructure formation were studied. • Duloxetine drug loading capability was studied. • Sustained release of duloxetine was evaluated. - Abstract: A new group of mesoporous silica nanoparticles (MSNs) were synthesized using combination pharmaceutical surfactants, Triton X-100 and Tween-40 as template and loaded with duloxetine hydrochloride (DX), for improving the sustained release of DX and patterns with high drug loading. Agglomerated spherical silica MSNs were synthesized by sol–gel and solvothermal methods. The calcined and drug loaded MSNs were characterized using X-ray diffraction (XRD), Braunner–Emmett–Teller (BET), thermogravimetric analysis (TGA), Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), diffuse reflectance ultraviolet–visible (DRS-UV–vis) spectroscopy. MSNs with high surface area and pore volume were selected and studied for their DX loading and release. The selected MSNs can accommodate a maximum of 34% DX within it. About 90% was released at 200 h and hence, the synthesized MSNs were capable of engulfing DX and sustain its release. Further form the Ritger and Peppas, Higuchi model for mechanism drug release from all the MSN matrices follows anomalous transport or Non-Fickian diffusion with the ‘r’ and ‘n’ value 0.9 and 0.45 < n < 1, respectively. So, from this study it could be concluded that the MSNs synthesized using pharmaceutical templates were better choice of reservoir for the controlled delivery of drug which requires sustained release.

  12. Radiation Synthesis of Functional Nanoparticles for Imaging, Sensing and Drug Delivery Applications

    International Nuclear Information System (INIS)

    Grasselli, M.; Soto Espinoza, S.; Risso, V.; Pawlak, E.; Smolko, E.E.

    2010-01-01

    In the present report we describe nanoparticle synthesis by ionizing radiation from globular proteins and methacrylate monomers. Dynamic light scattering and other spectroscopic methods were performed to characterize this new material

  13. Radiation Synthesis of Functional Nanoparticles for Imaging, Sensing and Drug Delivery Applications

    Energy Technology Data Exchange (ETDEWEB)

    Grasselli, M.; Soto Espinoza, S.; Risso, V.; Pawlak, E.; Smolko, E.E., E-mail: mgrasse@unq.edu.ar, E-mail: mariano.grasselli@gmail.com [Quesada 2422, piso 11, dpto. C, C1429 Buenos Aires (Argentina)

    2010-07-01

    In the present report we describe nanoparticle synthesis by ionizing radiation from globular proteins and methacrylate monomers. Dynamic light scattering and other spectroscopic methods were performed to characterize this new material.

  14. Magnetic field pattern synthesis and its application in targeted drug delivery: Design and implementation.

    Science.gov (United States)

    Hajiaghajani, Amirhossein; Abdolali, Ali

    2018-05-01

    In cancer therapy, magnetic drug targeting is considered as an effective treatment to reduce chemotherapy's side effects. The accurate design and shaping of magnetic fields are crucial for healthy cells to be immune from chemotherapeutics. In this paper, arbitrary 2-dimensional spatial patterns of magnetic fields from DC to megahertz are represented in terms of spatial Fourier spectra with sinusoidal eigenfunctions. Realization of each spatial frequency was investigated by a set of elliptical coils. Therefore, it is shown that the desired pattern was synthesized by simultaneous use of coil sets. Currents running on each set were obtained via fast and straightforward analytical Fourier series calculation. Experimentally scanned sample patterns were in close agreement with full wave analysis. Discussions include the evaluation of the Fourier series approximation error and cross-polarization of produced magnetic fields. It was observed that by employing the controlled magnetic field produced by the proposed setup, we were able to steer therapeutic particles toward the right or left half-spheres of the breast, with an efficiency of 90%. Such a pattern synthesizer may be employed in numerous human arteries as well as other bioelectromagnetic patterning applications, e.g., wireless power transfer, magnetic innervation, and tomography. Bioelectromagnetics. 39:325-338, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  15. Synthesis of mesoporous hollow silica nanospheres using polymeric micelles as template and their application as a drug-delivery carrier.

    Science.gov (United States)

    Sasidharan, Manickam; Zenibana, Haruna; Nandi, Mahasweta; Bhaumik, Asim; Nakashima, Kenichi

    2013-10-07

    Mesoporous hollow silica nanospheres with uniform particle sizes of 31-33 nm have been successfully synthesized by cocondensation of tetramethoxysilane (TMOS) and alkyltrimethoxysilanes [RSi(OR)3], where the latter also acts as a porogen. ABC triblock copolymer micelles of poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-PVP-PEO) with a core-shell-corona architecture have been employed as a soft template at pH 4. The cationic shell block with 2-vinyl pyridine groups facilitates the condensation of silica precursors under the sol-gel reaction conditions. Phenyltrimethoxysilane, octyltriethoxysilane, and octadecyltriethoxysilanes were used as porogens for generating mesopores in the shell matrix of hollow silica and the octadecyl precursor produced the largest mesopore among the different porogens, of dimension ca. 4.1 nm. The mesoporous hollow particles were thoroughly characterized by small-angle X-ray diffraction (SXRD), thermal (TG/DTA) and nitrogen sorption analyses, infra-red (FTIR) and nuclear magnetic resonance ((13)C-CP MAS NMR and (29)Si MAS NMR) spectroscopies, and transmission electron microscopy (TEM). The mesoporous hollow silica nanospheres have been investigated for drug-delivery application by an in vitro method using ibuprofen as a model drug. The hollow silica nanospheres exhibited higher storage capacity than the well-known mesoporous silica MCM-41. Propylamine functionalized hollow particles show a more sustained release pattern than their unfunctionalized counterparts, suggesting a huge potential of hollow silica nanospheres in the controlled delivery of small drug molecules.

  16. Synthesis and characterization of polyamidoamine dendrimer-coated multi-walled carbon nanotubes and their application in gene delivery systems

    Science.gov (United States)

    Pan, Bifeng; Cui, Daxiang; Xu, Ping; Ozkan, Cengiz; Feng, Gao; Ozkan, Mihri; Huang, Tuo; Chu, Bingfeng; Li, Qing; He, Rong; Hu, Guohan

    2009-03-01

    With the aim of improving the amount and delivery efficiency of genes taken by carbon nanotubes into human cancer cells, different generations of polyamidoamine dendrimer modified multi-walled carbon nanotubes (dMNTs) were fabricated, and characterized by high-resolution transmission electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis, revealing the presence of dendrimer capped on the surface of carbon nanotubes. The dMNTs fully conjugated with FITC-labeled antisense c-myc oligonucleotides (asODN), those resultant asODN-dMNTs composites were incubated with human breast cancer cell line MCF-7 cells and MDA-MB-435 cells, and liver cancer cell line HepG2 cells, and confirmed to enter into tumor cells within 15 min by laser confocal microscopy. These composites inhibited the cell growth in time- and dose-dependent means, and down-regulated the expression of the c-myc gene and C-Myc protein. Compared with the composites of CNT-NH2-asODN and dendrimer-asODN, no. 5 generation of dendrimer-modified MNT-asODN composites exhibit maximal transfection efficiencies and inhibition effects on tumor cells. The intracellular gene transport and uptake via dMNTs should be generic for the mammalian cell lines. The dMNTs have potentials in applications such as gene or drug delivery for cancer therapy and molecular imaging.

  17. Synthesis and characterization of polyamidoamine dendrimer-coated multi-walled carbon nanotubes and their application in gene delivery systems

    Energy Technology Data Exchange (ETDEWEB)

    Pan Bifeng; Cui Daxiang; Xu Ping; Feng Gao; Huang Tuo; Li Qing; He Rong [Department 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 JiaoTong University, 800 Dongchuan Road, Shanghai 200240 (China); Ozkan, Cengiz [Mechanical Engineering Department, University of California Riverside, 900 University Avenue-Riverside, CA 92521 (United States); Ozkan, Mihri [Electrical Engineering Department, University of California Riverside, 900 University Avenue, Riverside, CA 92521 (United States); Chu, Bingfeng [Department of Stomatology, General Hospital of PLA, 28 Fuxing Road, Beijing100853 (China); Hu Guohan [Department of Neurosurgery of Changzheng Hospital, 415 Fengyang Road, Second Military Medical University, Shanghai 20003 (China)], E-mail: dxcui@sjtu.edu.cn, E-mail: huguohan6504@sina.com

    2009-03-25

    With the aim of improving the amount and delivery efficiency of genes taken by carbon nanotubes into human cancer cells, different generations of polyamidoamine dendrimer modified multi-walled carbon nanotubes (dMNTs) were fabricated, and characterized by high-resolution transmission electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis, revealing the presence of dendrimer capped on the surface of carbon nanotubes. The dMNTs fully conjugated with FITC-labeled antisense c-myc oligonucleotides (asODN), those resultant asODN-dMNTs composites were incubated with human breast cancer cell line MCF-7 cells and MDA-MB-435 cells, and liver cancer cell line HepG2 cells, and confirmed to enter into tumor cells within 15 min by laser confocal microscopy. These composites inhibited the cell growth in time- and dose-dependent means, and down-regulated the expression of the c-myc gene and C-Myc protein. Compared with the composites of CNT-NH{sub 2}-asODN and dendrimer-asODN, no. 5 generation of dendrimer-modified MNT-asODN composites exhibit maximal transfection efficiencies and inhibition effects on tumor cells. The intracellular gene transport and uptake via dMNTs should be generic for the mammalian cell lines. The dMNTs have potentials in applications such as gene or drug delivery for cancer therapy and molecular imaging.

  18. Synthesis and characterization of polyamidoamine dendrimer-coated multi-walled carbon nanotubes and their application in gene delivery systems

    International Nuclear Information System (INIS)

    Pan Bifeng; Cui Daxiang; Xu Ping; Feng Gao; Huang Tuo; Li Qing; He Rong; Ozkan, Cengiz; Ozkan, Mihri; Chu, Bingfeng; Hu Guohan

    2009-01-01

    With the aim of improving the amount and delivery efficiency of genes taken by carbon nanotubes into human cancer cells, different generations of polyamidoamine dendrimer modified multi-walled carbon nanotubes (dMNTs) were fabricated, and characterized by high-resolution transmission electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis, revealing the presence of dendrimer capped on the surface of carbon nanotubes. The dMNTs fully conjugated with FITC-labeled antisense c-myc oligonucleotides (asODN), those resultant asODN-dMNTs composites were incubated with human breast cancer cell line MCF-7 cells and MDA-MB-435 cells, and liver cancer cell line HepG2 cells, and confirmed to enter into tumor cells within 15 min by laser confocal microscopy. These composites inhibited the cell growth in time- and dose-dependent means, and down-regulated the expression of the c-myc gene and C-Myc protein. Compared with the composites of CNT-NH 2 -asODN and dendrimer-asODN, no. 5 generation of dendrimer-modified MNT-asODN composites exhibit maximal transfection efficiencies and inhibition effects on tumor cells. The intracellular gene transport and uptake via dMNTs should be generic for the mammalian cell lines. The dMNTs have potentials in applications such as gene or drug delivery for cancer therapy and molecular imaging.

  19. Synthesis, Characterization, and Atenolol Delivery Application of Functionalized Mesoporous Hydroxyapatite Nanoparticles Prepared by Microwave-Assisted Co-precipitation Method.

    Science.gov (United States)

    Mortazavi-Derazkola, Sobhan; Naimi-Jamal, Mohammad Reza; Ghoreishi, Seyedeh Masoumeh

    2016-01-01

    Atenolol has been used to treat angina and hypertension, either alone or with other antihypertensives. Despite its usefulness, it shows some side effects such as diarrhea and nausea in some patients. A method for slow release of atenolol in intestine is helpful to prevent such side effects. A facile co-precipitation microwave-assisted method was used to fabricate mesoporous hydroxyapatite nanoparticles (mHAp). It was then functionalized to have SO3H groups. The synthesized material was used for storage/slow release study of atenolol. Atenolol loaded mHAp shows immediate release of atenolol in pH 8, whileafter functionalizing shows up to ca. 30% release at the beginning. In pH 1, 50% of drug was released after 10 h from AT@mHAp and after 18h the drug was almost completely released.The drug release profiles of functionalized HAp at pH value 1 and 8reveals the complete release of atenolol in intestine pH, while no complete release is observed in stomach environment. The aims of this work were synthesis and characterization of mesoporous HAp through the microwave-assisted co-precipitation method and elucidate the underlying drug release capability of mesoporous HAp nanoparticles. The SO3H group was incorporated into the mesoporous HAp and then used as drug delivery carriers using atenolol as a model drug to investigate their drug storage/release properties in simulated body fluid (SBF). Increasing pH value to 8 causes increase in the drug release.

  20. Synthesis, characterization and in vitro study of biocompatible cinnamaldehyde functionalized magnetite nanoparticles (CPGF Nps for hyperthermia and drug delivery applications in breast cancer.

    Directory of Open Access Journals (Sweden)

    Kirtee D Wani

    Full Text Available Cinnamaldehyde, the bioactive component of the spice cinnamon, and its derivatives have been shown to possess anti-cancer activity against various cancer cell lines. However, its hydrophobic nature invites attention for efficient drug delivery systems that would enhance the bioavailability of cinnamaldehyde without affecting its bioactivity. Here, we report the synthesis of stable aqueous suspension of cinnamaldehyde tagged Fe3O4 nanoparticles capped with glycine and pluronic polymer (CPGF NPs for their potential application in drug delivery and hyperthermia in breast cancer. The monodispersed superparamagnetic NPs had an average particulate size of ∼ 20 nm. TGA data revealed the drug payload of ∼ 18%. Compared to the free cinnamaldehyde, CPGF NPs reduced the viability of breast cancer cell lines, MCF7 and MDAMB231, at lower doses of cinnamaldehyde suggesting its increased bioavailability and in turn its therapeutic efficacy in the cells. Interestingly, the NPs were non-toxic to the non-cancerous HEK293 and MCF10A cell lines compared to the free cinnamaldehyde. The novelty of CPGF nanoparticulate system was that it could induce cytotoxicity in both ER/PR positive/Her2 negative (MCF7 and ER/PR negative/Her2 negative (MDAMB231 breast cancer cells, the latter being insensitive to most of the chemotherapeutic drugs. The NPs decreased the growth of the breast cancer cells in a dose-dependent manner and altered their migration through reduction in MMP-2 expression. CPGF NPs also decreased the expression of VEGF, an important oncomarker of tumor angiogenesis. They induced apoptosis in breast cancer cells through loss of mitochondrial membrane potential and activation of caspase-3. Interestingly, upon exposure to the radiofrequency waves, the NPs heated up to 41.6 °C within 1 min, suggesting their promise as a magnetic hyperthermia agent. All these findings indicate that CPGF NPs prove to be potential nano-chemotherapeutic agents in breast cancer.

  1. Synthesis and Structural Characterization of Bioactive PHA and γ-PGA Oligomers for Potential Applications as a Delivery System

    Directory of Open Access Journals (Sweden)

    Iwona Kwiecień

    2016-04-01

    Full Text Available The (transesterification reaction of bacterial biopolymers with a selected bioactive compound with a hydroxyl group was applied as a convenient method for obtaining conjugates of such compound. Tyrosol, a naturally occurring phenolic compound, was selected as a model of a bioactive compound with a hydroxyl group. Selected biodegradable polyester and polyamide, poly(3-hydroxybutyrate-co-4-hydroxybutyrate (P(3HB-co-4HB and poly-γ-glutamic acid (γ-PGA, respectively, were used. The (transesterification reactions were carried out in melt mediated by 4-toluenesulfonic acid monohydrate. The structures of (transesterification products were established at the molecular level with the aid of ESI-MS2 (electrospray ionization tandem mass spectrometry and/or 1H NMR (nuclear magnetic resonance techniques. Performed analyses confirmed that the developed method leads to the formation of conjugates in which bioactive compounds are covalently bonded to biopolymer chains. The amount of covalently bonded bioactive compounds in the resulting conjugates depends on the type of biopolymers applied in synthesis.

  2. Promising applications in drug delivery systems of a novel β-cyclodextrin derivative obtained by green synthesis.

    Science.gov (United States)

    García, Agustina; Leonardi, Darío; Lamas, María C

    2016-01-15

    An efficient and green method has been developed for the synthesis of succinyl-β-cyclodextrin in aqueous media obtaining very good yield. Acidic groups have been introduced in the synthesized carrier molecule to improve the guest-host affinity. To evaluate the suitability of the novel excipient focused to develop oral dosage forms, albendazole, a BSC class II compound, was chosen as a model drug. The β-cyclodextrin derivative and the inclusion complex were thoroughly characterized in solution and solid state by phase solubility studies, FT-IR spectroscopy, SEM, XRD, ESI-MS, DSC, 1D (1)H NMR, 1D (13)C NMR, selective 1D TOCSY, 2D COSY, 2D HSQC, 2D HMBC and ROESY NMR spectroscopy. Phase solubility studies indicated that both of them β-cyclodextrin and succinyl-β-cyclodextrin formed 1:1 inclusion complexes with albendazole, and the stability constants were 68M(-1) (β-cyclodextrin), 437M(-1) (succinyl-β-cyclodextrin), respectively. Water solubility and dissolution rate of albendazole were significantly improved in complex forms. Thus, the succinyl-β-cyclodextrin derivative could be a promising excipient to design oral dosage forms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Biopolymers/poly(ε-caprolactone)/polyethylenimine functionalized nano-hydroxyapatite hybrid cryogel: Synthesis, characterization and application in gene delivery.

    Science.gov (United States)

    Simionescu, Bogdan C; Drobota, Mioara; Timpu, Daniel; Vasiliu, Tudor; Constantinescu, Cristina Ana; Rebleanu, Daniela; Calin, Manuela; David, Geta

    2017-12-01

    Nano-hydroxyapatite (nHAp), surface functionalized with linear polyethylenimine (LPEI), was used for the preparation of biocomposites in combination with biopolymers and poly(ε-caprolactone) (PCL), by cryogelation technique, to yield biomimetic scaffolds with controlled interconnected macroporosity, mechanical stability, and predictable degradation behavior. The structural characteristics, swelling and degradation behavior of hydroxyapatite and hydroxyapatite/β-tricalcium phosphate (β-TCP) filled matrices were investigated as compared to the corresponding naked polymer 3D system. It was found that the homogeneity and cohesivity of the composite are significantly dependent on the size and amount of the included inorganic particles, which are thus determining the structural parameters. Surface modification with LPEI and nanodimensions favored the nHAp integration in the organic matrix, with preferential location along protein fibers, while β-TCP microparticles induced an increased disorder in the hybrid system. The biocomposite including nHAp only was further investigated targeting biomedical uses, and proved to be non-cytotoxic and capable of acting as gene-activated matrix (GAM). It allowed sustained delivery over time (until 22days) of embedded PEI 25 -pDNA polyplexes at high levels of transgene expression, while insuring a decrease in cytotoxicity as compared to polyplexes alone. Experimental data recommend such biocomposite as an attractive material for regenerative medicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Synthesis and characterization of N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan chloride for potential application in gene delivery.

    Science.gov (United States)

    Xiao, Bo; Wan, Ying; Wang, Xiaoyu; Zha, Qichen; Liu, Haoming; Qiu, Zhiye; Zhang, Shengmin

    2012-03-01

    A series of N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan chloride (HTCC) samples with various degrees of quaternization ranging from 12.4 to 43.7% was synthesized. The structures and properties of HTCC were investigated by FT-IR, (1)H NMR, conductometric titration and XRD analysis. It was found that HTCC had a more amorphous structure than chitosan. HTCC samples showed significantly lower cytotoxicity than polyethyleneimine in HepG2 and HeLa cell lines. The samples spontaneously formed complexes with pGL3 luciferase plasmid. These complexes had desirable particle sizes (160-300 nm) and zeta potentials (10.8-18.7 mV) when the weight ratios of HTCC to plasmid altered in the range of 3:1-20:1. In vitro gene transfection results indicated that HTCC had significantly high transfection efficiency compared with chitosan for delivering pGL3 luciferase plasmid to HeLa cells. The results suggest that HTCC could be a promising non-viral vector for safe and efficient DNA delivery. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Synthesis and characterization of insulin/zirconium phosphate@TiO2 hybrid composites for enhanced oral insulin delivery applications.

    Science.gov (United States)

    Safari, Mostafa; Kamari, Younes; Ghiaci, Mehran; Sadeghi-Aliabadi, Hojjat; Mirian, Mina

    2017-05-01

    In this work, a series of composites of insulin (Ins)/zirconium phosphate (ZrP) were synthesized by intercalation method, then, these composites were coated with TiO 2 by sol-gel method to prepare Ins/ZrP@TiO 2 hybrid composites and the drug release of the composites was investigated by using UV-Vis spectroscopy. Ins/ZrP (10, 30, 60 wt%) composites were prepared by intercalation of insulin into the ZrP layers in water. Then Ins/ZrP composites were coated with different amounts of TiO 2 (30, 50, 100 wt %) by using titanium tetra n-butoxide, as precursor. Formation of intercalated Ins/ZrP and Ins/ZrP@TiO 2 hybrid composites was characterized by FT-IR, FE-SEM, BET and XRD analysis. Zeta potential of the optimized Ins/ZrP@TiO 2 hybrid composite was determined -27.2 mV. Cytotoxic effects of the optimized Ins/ZrP@TiO 2 hybrid composite against HeLa and Hek293T cell lines were evaluated using MTT assay and the results showed that designed drug delivery system was not toxic in biological environment. Compared to the Ins/ZrP composites, incorporation of TiO 2 coating enhanced the drug entrapment considerably, and reduced the drug release. The Ins/ZrP composites without TiO 2 coating released the whole drug after 30 min in pH 7.4 (phosphate buffer solution) while the TiO 2 -coated composites released the entrapped drug after 20 h. In addition to increasing the shelf life of hormone, this nanoencapsulation and nanocoating method can convert the insulin utilization from injection to oral and present a painless and more comfortable treatment for diabetics.

  6. Radiation Synthesis and Characterization of Polyvinyl alcohol/Acrylic acid Hydrogel and its Amoxicillin drug Delivery application

    International Nuclear Information System (INIS)

    El kelesh, N.A.; Ismail, S.A.; Abd El Wahab, S.Y.

    2012-01-01

    Polyvinyl alcohol /Acrylic acid based hydrogels can be synthesized by Gamma radiation technique using 60 Co irradiation cell at irradiation dose rate 1.8 Gray/second. The optimum conditions of hydrogel preparation takes place at different factors such as composition ratios of PVA/AAc, different comonomer concentration and different irradiation doses resulting in hydrogel with maximum gel percent as it obtained 98%. The structures of hydrogels were characterized by FTIR analysis. The results can be confirmed the expected structures as well as free radical copolymerization. According to the swelling studies, hydrogels with high content of AAc gave relatively high swelling percent. The hydrogel showed a super adsorbent with swelling capacity 10320 %. Water diffusion into such prepared hydrogel showed a non-Fickian type where a Fickian number was 0.77. This hydrogel was used for the adsorption of amoxicillin drug from their aqueous solutions. The factors affected on the uptake conditions such as ph, time and initial feed concentration on the amoxicillin adsorption capacity of hydrogel was studied depending on Freundlish model of adsorption isotherm.. It was observed that the interaction between drug and ionic comonomers was enhanced in alkaline medium and high initial feed concentration of the drug. The ability of the hydrogel and the affinity of the drug to be adsorbed can be cleared by determining the empirical constants n and k respectively from the logarithmic form of Freundlish equation. The recovery of drug was also investigated in different ph values to study the suitable condition of drug release as drug delivery system.

  7. Multifunctional Nanoparticles for Drug Delivery Applications Imaging, Targeting, and Delivery

    CERN Document Server

    Prud'homme, Robert

    2012-01-01

    This book clearly demonstrates the progression of nanoparticle therapeutics from basic research to applications. Unlike other books covering nanoparticles used in medical applications, Multifunctional Nanoparticles for Drug Delivery Applications presents the medical challenges that can be reduced or even overcome by recent advances in nanoscale drug delivery. Each chapter highlights recent progress in the design and engineering of select multifunctional nanoparticles with topics covering targeting, imaging, delivery, diagnostics, and therapy.

  8. Synthesis and toxicity test of magnetic nanoparticle via biocompatible microemulsion system as template for application in targeted drug delivery

    Science.gov (United States)

    Kader, Razinah Abdul; Rose, Laili Che; Suhaimi, Hamdan; Manickam, Mariessa Soosai

    2017-09-01

    This work reports the preparation of magnetic nanoparticles (FeNPs) using biocompatible W/O microemulsion for biomedical applications. W/O microemulsion was formed using decane as oil phase, water, tween 80 as non-ionic surfactant and hexanol as organic solvent. The synthesized FeNPs were characterised by using Fourier Transform Infrared Resonance Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). The FTIR showed that Fe-O bond exist on 581cm-1 having strong magnetic strength whereas SEM showed the morphology surface of magnetic nanoparticles (FeNPs). Furthermore, analysis of XRD pattern magnetic nanoparticles (FeNPs) reveals a cubic iron oxide phase with good crystallize structure. Furthermore, toxicity test on human liver cells proved that it is 70% safe on human and proved to be a safety nanomedicine.

  9. Cyclodextrins in delivery systems: Applications

    Directory of Open Access Journals (Sweden)

    Gaurav Tiwari

    2010-01-01

    Full Text Available Cyclodextrins (CDs are a family of cyclic oligosaccharides with a hydrophilic outer surface and a lipophilic central cavity. CD molecules are relatively large with a number of hydrogen donors and acceptors and, thus in general, they do not permeate lipophilic membranes. In the pharmaceutical industry, CDs have mainly been used as complexing agents to increase aqueous solubility of poorly soluble drugs and to increase their bioavailability and stability. CDs are used in pharmaceutical applications for numerous purposes, including improving the bioavailability of drugs. Current CD-based therapeutics is described and possible future applications are discussed. CD-containing polymers are reviewed and their use in drug delivery is presented. Of specific interest is the use of CD-containing polymers to provide unique capabilities for the delivery of nucleic acids. Studies in both humans and animals have shown that CDs can be used to improve drug delivery from almost any type of drug formulation. Currently, there are approximately 30 different pharmaceutical products worldwide containing drug/CD complexes in the market.

  10. Asymmetrical Polymer Vesicles for Drug delivery and Other Applications

    Directory of Open Access Journals (Sweden)

    Yi Zhao

    2017-06-01

    Full Text Available Scientists have been attracted by polymersomes as versatile drug delivery systems since the last two decades. Polymersomes have the potential to be versatile drug delivery systems because of their tunable membrane formulations, stabilities in vivo, various physicochemical properties, controlled release mechanisms, targeting abilities, and capacities to encapsulate a wide range of drugs and other molecules. Asymmetrical polymersomes are nano- to micro-sized polymeric capsules with asymmetrical membranes, which means, they have different outer and inner coronas so that they can exhibit better endocytosis rate and endosomal escape ability than other polymeric systems with symmetrical membranes. Hence, asymmetrical polymersomes are highly promising as self-assembled nano-delivery systems in the future for in vivo therapeutics delivery and diagnostic imaging applications. In this review, we prepared a summary about recent research progresses of asymmetrical polymersomes in the following aspects: synthesis, preparation, applications in drug delivery and others.

  11. Recent Advances in the Synthesis of Graphene-Based Nanomaterials for Controlled Drug Delivery

    Directory of Open Access Journals (Sweden)

    Zhuqing Wang

    2017-11-01

    Full Text Available Graphene-based nanomaterials have exhibited wide applications in nanotechnology, materials science, analytical science, and biomedical engineering due to their unique physical and chemical properties. In particular, graphene has been an excellent nanocarrier for drug delivery application because of its two-dimensional structure, large surface area, high stability, good biocompatibility, and easy surface modification. In this review, we present the recent advances in the synthesis and drug delivery application of graphene-based nanomaterials. The modification of graphene and the conjugation of graphene with other materials, such as small molecules, nanoparticles, polymers, and biomacromolecules as functional nanohybrids are introduced. In addition, the controlled drug delivery with the fabricated graphene-based nanomaterials are demonstrated in detail. It is expected that this review will guide the chemical modification of graphene for designing novel functional nanohybrids. It will also promote the potential applications of graphene-based nanomaterials in other biomedical fields, like biosensing and tissue engineering.

  12. Star-Shaped Polypeptides: Synthesis and Opportunities for Delivery of Therapeutics.

    Science.gov (United States)

    Byrne, Mark; Murphy, Robert; Kapetanakis, Antonios; Ramsey, Joanne; Cryan, Sally-Ann; Heise, Andreas

    2015-09-17

    Significant advances in the synthesis of polypeptides by N-carboxyanhydride (NCA) polymerisation over the last decade have enabled the design of advanced polypeptide architectures such as star-shaped polypeptides. These materials combine the functionality offered by amino acids with the flexibility of creating stable nanoparticles with adjustable cargo space for therapeutic delivery. This review highlights recent advances in the synthesis of star polypeptides by NCA polymerisation followed by a critical review of the applications of this class of polymer in the delivery of therapeutic agents. This includes examples of traditional small-molecule drugs as well as the emerging class of biologics such as genetic therapeutics (gene delivery). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Synthesis and application of intelligent hydrogels

    International Nuclear Information System (INIS)

    Kaetsu, I.; Uchida, K.; Sutani, K.; Nakayama, H.; Tamori, A.

    2000-01-01

    The authors have studied synthesis and application of stimule-sensitive and responsive hydrogels. In this report, two kinds of investigations were carried out on the intelligent hydrogels and the applications with radiation techniques. 1. Synthesis of temperature responsive sol-gel transition polymer and the application to drug delivery systems. Polysopropyl acrylamide is a typical temperature responsive polymers and the copolymers show broad variation of LCST (sol-gel transition temperature). The various copolymers of isopropyl acrylamide were synthesized by UV or radiation. 2. Surface curing of pH and electric field responsive hydrogel and the application to drug delivery systems. Electrolyte monomers such as acrylic acid was coated on the surface of polymer membrane (porous or non-porous) including drugs, and cured by UV or radiation various enzymes were immobilized in the coating layer in many cases. The product showed pH, electro-field and substrate responsive releases of model drug under on-off switching of environmental conditions. (J.P.N.)

  14. Synthesis and application of intelligent hydrogels

    Energy Technology Data Exchange (ETDEWEB)

    Kaetsu, I.; Uchida, K.; Sutani, K.; Nakayama, H.; Tamori, A. [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology

    2000-03-01

    The authors have studied synthesis and application of stimule-sensitive and responsive hydrogels. In this report, two kinds of investigations were carried out on the intelligent hydrogels and the applications with radiation techniques. 1. Synthesis of temperature responsive sol-gel transition polymer and the application to drug delivery systems. Polysopropyl acrylamide is a typical temperature responsive polymers and the copolymers show broad variation of LCST (sol-gel transition temperature). The various copolymers of isopropyl acrylamide were synthesized by UV or radiation. 2. Surface curing of pH and electric field responsive hydrogel and the application to drug delivery systems. Electrolyte monomers such as acrylic acid was coated on the surface of polymer membrane (porous or non-porous) including drugs, and cured by UV or radiation various enzymes were immobilized in the coating layer in many cases. The product showed pH, electro-field and substrate responsive releases of model drug under on-off switching of environmental conditions. (J.P.N.)

  15. Voice synthesis application

    Science.gov (United States)

    Lightstone, P. C.; Davidson, W. M.

    1982-04-01

    The military detection assessment laboratory houses an experimental field system which assesses different alarm indicators such as fence disturbance sensors, MILES cables, and microwave Racons. A speech synthesis board which could be interfaced, by means of a computer, to an alarm logger making verbal acknowledgement of alarms possible was purchased. Different products and different types of voice synthesis were analyzed before a linear predictive code device produced by Telesensory Speech Systems of Palo Alto, California was chosen. This device is called the Speech 1000 Board and has a dedicated 8085 processor. A multiplexer card was designed and the Sp 1000 interfaced through the card into a TMS 990/100M Texas Instrument microcomputer. It was also necessary to design the software with the capability of recognizing and flagging an alarm on any 1 of 32 possible lines. The experimental field system was then packaged with a dc power supply, LED indicators, speakers, and switches, and deployed in the field performing reliably.

  16. Detonation-synthesis nanodiamonds: synthesis, structure, properties and applications

    Energy Technology Data Exchange (ETDEWEB)

    Dolmatov, Valerii Yu [Federal State Unitary Enterprise Special Design-Technology Bureau (FSUE SDTB) ' ' Tekhnolog' ' at the St Petersburg State Institute of Technology (Technical University) (Russian Federation)

    2007-04-30

    The review outlines the theoretical foundations and industrial implementations of modern detonation synthesis of nanodiamonds and chemical purification of the nanodiamonds thus obtained. The structure, key properties and promising fields of application of detonation-synthesis nanodiamonds are considered.

  17. Detonation-synthesis nanodiamonds: synthesis, structure, properties and applications

    International Nuclear Information System (INIS)

    Dolmatov, Valerii Yu

    2007-01-01

    The review outlines the theoretical foundations and industrial implementations of modern detonation synthesis of nanodiamonds and chemical purification of the nanodiamonds thus obtained. The structure, key properties and promising fields of application of detonation-synthesis nanodiamonds are considered.

  18. Metabolic approaches to enhance transdermal drug delivery. 1. Effect of lipid synthesis inhibitors.

    Science.gov (United States)

    Tsai, J C; Guy, R H; Thornfeldt, C R; Gao, W N; Feingold, K R; Elias, P M

    1996-06-01

    The intercellular domains of the stratum corneum, which contain a mixture of cholesterol, free fatty acids, and ceramides, mediate both the epidermal permeability barrier and the transdermal delivery of both lipophilic and hydrophilic molecules. Prior studies have shown that each of the three key lipid classes is required for normal barrier function. For example, selective inhibition of either cholesterol, fatty acid, or ceramide synthesis in the epidermis delays barrier recovery rates after barrier perturbation of hairless mouse skin in vivo. In this study, we investigated the potential of certain inhibitors of lipid synthesis to enhance the transdermal delivery of lidocaine or caffeine as a result of their capacity to perturb barrier homeostasis. After acetone disruption of the barrier, the extent of lidocaine delivery and the degree of altered barrier function paralleled each other. Moreover, the further alteration in barrier function produced by either the fatty acid synthesis inhibitor 5-(tetradecyloxy)-2-furancarboxylic acid (TOFA), the cholesterol synthesis inhibitor fluvastatin (FLU), or cholesterol sulfate (CS) resulted in a further increase in lidocaine absorption. Furthermore, coapplications of TOFA and CS together caused an additive increase in lidocaine uptake. Finally, a comparable increase in drug delivery occurred when the barrier was disrupted initially with DMSO instead of acetone; coapplications of TOFA and FLU together again delayed barrier recovery and increased drug delivery by about 8-fold vs delivery from a standard enhancing vehicle. Whereas these metabolic inhibitors also variably increased the octanol/water partitioning of the drugs studied (perhaps via complexion or pH alterations), physicochemical effects of the inhibitors alone did not alter drug uptake in intact skin; i.e., passive mechanisms alone cannot account for the net increase in drug delivery. Our results show that modulations of epidermal lipid biosynthesis, following

  19. Synthesis of the project leadership staffing needs for successful development of alternative delivery programs.

    Science.gov (United States)

    2017-08-01

    This research provides a synthesis of practices in organizational structuring and professional staffing of the innovative delivery units in several state DOTs across the nation that are actively utilizing alternative project delivery. Several major c...

  20. Ferroic materials synthesis and applications

    CERN Document Server

    Virk, Hardev Singh

    2015-01-01

    Ferroics is the generic name given to the study of ferromagnets, ferroelectrics, and ferroelastics. The basis of this study is to understand the large changes in physical characteristics that occur over a very narrow temperature range. In recent years, a new class of ferroic materials has been attracting increased interest. These multiferroics exhibit more than one ferroic property simultaneously in a single phase. The present volume: ""Ferroic Materials: Synthesis and Applications"" has ten Chapters, spread over areas as diverse as Magnetic Oxide Nanomaterials, Ferrites Synthesis, Hexaferrite

  1. Facile synthesis of highly biocompatible folic acid-functionalised SiO2 nanoparticles encapsulating rare-earth metal complexes, and their application in targeted drug delivery.

    Science.gov (United States)

    Xu, Xiuling; Hu, Fan; Shuai, Qi

    2017-11-14

    Mesoporous silica core-shell nanospheres encapsulating a rare-earth metal complex (RC) were first synthesised through a facile W/O (water in oil) inverse microemulsion method. In order to achieve targeted complex delivery, folic acid (FA) was used as the targeting component due to its high affinity for over-expressed folate receptors (FRs) in cancer cells. The RC 2 @SiO 2 -FA nanospheres were characterised via ultraviolet-visible light absorption spectroscopy (UV-vis spectroscopy), dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A microwave method was used to synthesise five RC cores based on 4-chlorophenoxyacetic acid, and their crystal structures were further confirmed using X-ray diffraction. The five RC cores have the following chemical formulae: [Er 2 (p-CPA) 6 (H 2 O) 6 ] RC 1 , [Ho 2 (p-CPA) 6 (H 2 O) 6 ] RC 2 , [Sm(p-CPA) 3 (H 2 O)] RC 3 , [Pr(p-CPA) 3 (H 2 O)]·3H 2 O RC 4 and [Ce(p-CPA) 3 (H 2 O) 2 ]·2H 2 O RC 5 . The carboxyl groups showed two kinds of coordination modes, namely μ 2 -η 1 :η 1 and μ 2 -η 1 :η 2 , among RC 1 -RC 5 . The flexible -OCH 2 COO- spacer group, which can undergo rotation of its C-O and C-C bonds, offered great potential for structural diversity. In vivo experiments revealed that the nanospheres exhibited no obvious cytotoxicity on HepG2 cells and 293 T cells, even at concentrations of up to 80 μg mL -1 . Nevertheless, all of the RC cores showed a certain degree of anti-tumour efficacy; in particular, RC 2 showed the strongest cytotoxicity against HepG2 cells. Interestingly, the cytotoxicity of all of the RC 2 @SiO 2 -FA nanospheres was higher than that of lone RC 2 . These types of FA-targeted mesoporous silica nanocarriers can be used for the delivery of anti-tumour RC, and provide a basis for the further study of affordable non-platinum-based complexes.

  2. From Delivery to Adoption of Physical Activity Guidelines: Realist Synthesis

    Directory of Open Access Journals (Sweden)

    Liliana Leone

    2017-10-01

    Full Text Available Background: Evidence-based guidelines published by health authorities for the promotion of health-enhancing physical activity (PA, continue to be implemented unsuccessfully and demonstrate a gap between evidence and policies. This review synthesizes evidence on factors influencing delivery, adoption and implementation of PA promotion guidelines within different policy sectors (e.g., health, transport, urban planning, sport, education. Methods: Published literature was initially searched using PubMed, EBSCO, Google Scholar and continued through an iterative snowball technique. The literature review spanned the period 2002–2017. The realist synthesis approach was adopted to review the content of 39 included studies. An initial programme theory with a four-step chain from evidence emersion to implementation of guidelines was tested. Results: The synthesis furthers our understanding of the link between PA guidelines delivery and the actions of professionals responsible for implementation within health services, school departments and municipalities. The main mechanisms identified for guidance implementation were scientific legitimation, enforcement, feasibility, familiarity with concepts and PA habits. Threats emerged to the successful implementation of PA guidelines at national/local jurisdictional levels. Conclusions: The way PA guidelines are developed may influence their adoption by policy-makers and professionals. Useful lessons emerged that may inform synergies between policymaking and professional practices, promoting win-win multisectoral strategies.

  3. Hydroxyapatite hierarchically nanostructured porous hollow microspheres: rapid, sustainable microwave-hydrothermal synthesis by using creatine phosphate as an organic phosphorus source and application in drug delivery and protein adsorption.

    Science.gov (United States)

    Qi, Chao; Zhu, Ying-Jie; Lu, Bing-Qiang; Zhao, Xin-Yu; Zhao, Jing; Chen, Feng; Wu, Jin

    2013-04-22

    Hierarchically nanostructured porous hollow microspheres of hydroxyapatite (HAP) are a promising biomaterial, owing to their excellent biocompatibility and porous hollow structure. Traditionally, synthetic hydroxyapatite is prepared by using an inorganic phosphorus source. Herein, we report a new strategy for the rapid, sustainable synthesis of HAP hierarchically nanostructured porous hollow microspheres by using creatine phosphate disodium salt as an organic phosphorus source in aqueous solution through a microwave-assisted hydrothermal method. The as-obtained products are characterized by powder X-ray diffraction (XRD), Fourier-transform IR (FTIR) spectroscopy, SEM, TEM, Brunauer-Emmett-Teller (BET) nitrogen sorptometry, dynamic light scattering (DLS), and thermogravimetric analysis (TGA). SEM and TEM micrographs show that HAP hierarchically nanostructured porous hollow microspheres consist of HAP nanosheets or nanorods as the building blocks and DLS measurements show that the diameters of HAP hollow microspheres are within the range 0.8-1.5 μm. The specific surface area and average pore size of the HAP porous hollow microspheres are 87.3 m(2) g(-1) and 20.6 nm, respectively. The important role of creatine phosphate disodium salt and the influence of the experimental conditions on the products were systematically investigated. This method is facile, rapid, surfactant-free and environmentally friendly. The as-prepared HAP porous hollow microspheres show a relatively high drug-loading capacity and protein-adsorption ability, as well as sustained drug and protein release, by using ibuprofen as a model drug and hemoglobin (Hb) as a model protein, respectively. These experiments indicate that the as-prepared HAP porous hollow microspheres are promising for applications in biomedical fields, such as drug delivery and protein adsorption. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Sustained Release Drug Delivery Applications of Polyurethanes

    Directory of Open Access Journals (Sweden)

    Michael B. Lowinger

    2018-05-01

    Full Text Available Since their introduction over 50 years ago, polyurethanes have been applied to nearly every industry. This review describes applications of polyurethanes to the development of modified release drug delivery. Although drug delivery research leveraging polyurethanes has been ongoing for decades, there has been renewed and substantial interest in the field in recent years. The chemistry of polyurethanes and the mechanisms of drug release from sustained release dosage forms are briefly reviewed. Studies to assess the impact of intrinsic drug properties on release from polyurethane-based formulations are considered. The impact of hydrophilic water swelling polyurethanes on drug diffusivity and release rate is discussed. The role of pore formers in modulating drug release rate is examined. Finally, the value of assessing mechanical properties of the dosage form and approaches taken in the literature are described.

  5. Aerosol generation and delivery in medical applications

    International Nuclear Information System (INIS)

    Soni, P.S.; Raghunath, B.

    1998-01-01

    It is well established that radioaerosol lung technique by inhalation is a very versatile technique in the evaluation of health effects and medical diagnostic applications, especially to detect chronic obstructive pulmonary diseases, their defence mechanism permeability and many others. Most important part of aerosol technology is to generate reproducibly stable diagnostic radioaerosols of known characteristics. Many compressed air atomisers are commercially available for generating aerosols but they have limited utility in aerosol inhalation, either because of large droplet size, low aerosol output or high airflow rates. There is clearly a need for a versatile and economical aerosol generation/inhalation system that can produce dry labelled aerosol particles with high deep lung delivery efficiency suitable for clinical studies. BARC (Bhabha Atomic Research Centre) has developed a dry aerosol generation/delivery system which operates on compressed air and generates dry polydisperse aerosols. This system is described along with an assessment of the aerosol characteristics and efficiency for diagnosis of various respiratory disorders

  6. Large pore mesoporous silica nanomaterials for application in delivery of biomolecules

    Science.gov (United States)

    Knežević, Nikola Ž.; Durand, Jean-Olivier

    2015-01-01

    Various approaches for the synthesis of mesoporous silicate nanoparticles (MSN) with large pore (LP) diameters (in the range of 3-50 nm) are reviewed in this article. The work also covers the construction of magnetic analogues of large pore-mesoporous silica nanoparticles (LPMMSN) and their biomedical applications. The constructed materials exhibit vast potential for application in the loading and delivery of large drug molecules and biomolecules. Literature reports on the application of LPMSN and LPMMSN materials for the adsorption and delivery of proteins, enzymes, antibodies, and nucleic acids are covered in depth, which exemplify their highly potent characteristics for use in drug and biomolecule delivery to diseased tissues.Various approaches for the synthesis of mesoporous silicate nanoparticles (MSN) with large pore (LP) diameters (in the range of 3-50 nm) are reviewed in this article. The work also covers the construction of magnetic analogues of large pore-mesoporous silica nanoparticles (LPMMSN) and their biomedical applications. The constructed materials exhibit vast potential for application in the loading and delivery of large drug molecules and biomolecules. Literature reports on the application of LPMSN and LPMMSN materials for the adsorption and delivery of proteins, enzymes, antibodies, and nucleic acids are covered in depth, which exemplify their highly potent characteristics for use in drug and biomolecule delivery to diseased tissues. Dedicated to Professor Jeffrey I. Zink on the occasion of his 70th birthday.

  7. Microfluidic-Based Synthesis of Hydrogel Particles for Cell Microencapsulation and Cell-Based Drug Delivery

    Directory of Open Access Journals (Sweden)

    Jiandi Wan

    2012-04-01

    Full Text Available Encapsulation of cells in hydrogel particles has been demonstrated as an effective approach to deliver therapeutic agents. The properties of hydrogel particles, such as the chemical composition, size, porosity, and number of cells per particle, affect cellular functions and consequently play important roles for the cell-based drug delivery. Microfluidics has shown unparalleled advantages for the synthesis of polymer particles and been utilized to produce hydrogel particles with a well-defined size, shape and morphology. Most importantly, during the encapsulation process, microfluidics can control the number of cells per particle and the overall encapsulation efficiency. Therefore, microfluidics is becoming the powerful approach for cell microencapsulation and construction of cell-based drug delivery systems. In this article, I summarize and discuss microfluidic approaches that have been developed recently for the synthesis of hydrogel particles and encapsulation of cells. I will start by classifying different types of hydrogel material, including natural biopolymers and synthetic polymers that are used for cell encapsulation, and then focus on the current status and challenges of microfluidic-based approaches. Finally, applications of cell-containing hydrogel particles for cell-based drug delivery, particularly for cancer therapy, are discussed.

  8. One-Pot Parallel Synthesis of Lipid Library via Thiolactone Ring Opening and Screening for Gene Delivery.

    Science.gov (United States)

    Molla, Mijanur R; Böser, Alexander; Rana, Akshita; Schwarz, Karina; Levkin, Pavel A

    2018-04-18

    Efficient delivery of nucleic acids into cells is of great interest in the field of cell biology and gene therapy. Despite a lot of research, transfection efficiency and structural diversity of gene-delivery vectors are still limited. A better understanding of the structure-function relationship of gene delivery vectors is also essential for the design of novel and intelligent delivery vectors, efficient in "difficult-to-transfect" cells and in vivo clinical applications. Most of the existing strategies for the synthesis of gene-delivery vectors require multiple steps and lengthy procedures. Here, we demonstrate a facile, three-component one-pot synthesis of a combinatorial library of 288 structurally diverse lipid-like molecules termed "lipidoids" via a thiolactone ring opening reaction. This strategy introduces the possibility to synthesize lipidoids with hydrophobic tails containing both unsaturated bonds and reducible disulfide groups. The whole synthesis and purification are convenient, extremely fast, and can be accomplished within a few hours. Screening of the produced lipidoids using HEK293T cells without addition of helper lipids resulted in identification of highly stable liposomes demonstrating ∼95% transfection efficiency with low toxicity.

  9. Synthesis of boron nitride nanotubes and their applications

    Directory of Open Access Journals (Sweden)

    Saban Kalay

    2015-01-01

    Full Text Available Boron nitride nanotubes (BNNTs have been increasingly investigated for use in a wide range of applications due to their unique physicochemical properties including high hydrophobicity, heat and electrical insulation, resistance to oxidation, and hydrogen storage capacity. They are also valued for their possible medical and biomedical applications including drug delivery, use in biomaterials, and neutron capture therapy. In this review, BNNT synthesis methods and the surface modification strategies are first discussed, and then their toxicity and application studies are summarized. Finally, a perspective for the future use of these novel materials is discussed.

  10. Triboluminescence theory, synthesis, and application

    CERN Document Server

    Okoli, Okenwa; Fontenot, Ross; Hollerman, William

    2016-01-01

    This book expounds on progress made over the last 35 years in the theory, synthesis, and application of triboluminescence for creating smart structures. It presents in detail the research into utilization of the triboluminescent properties of certain crystals as new sensor systems for smart engineering structures, as well as triboluminescence-based sensor systems that have the potential to enable wireless, in-situ, real time and distributed (WIRD) structural health monitoring of composite structures. The sensor component of any structural health monitoring (SHM) technology — measures the effects of the external load/event and provides the necessary inputs for appropriate preventive/corrective action to be taken in a smart structure — sits at the heart of such a system. This volume explores advances in materials properties and structural behavior underlying creation of smart composite structures and sensor systems for structural health monitoring of critical engineering structures, such as bridges, aircraf...

  11. Polymer Brushes: Synthesis, Characterization, Applications

    Science.gov (United States)

    Advincula, Rigoberto C.; Brittain, William J.; Caster, Kenneth C.; Rühe, Jürgen

    2004-09-01

    Materials scientists, polymer chemists, surface physicists and materials engineers will find this book a complete and detailed treatise on the field of polymer brushes, their synthesis, characterization and manifold applications. In a first section, the various synthetic pathways and different surface materials are introduced and explained, followed by a second section covering important aspects of characterization and analysis in both flat surfaces and particles. These specific surface initiated polymerization (SIP) systems such as linear polymers, homopolymers, block copolymers, and hyperbranched polymers are unique compared to previously reported systems by chemisorption or physisorption. They have found their way in both large-scale and miniature applications of polymer brushes, which is covered in the last section. Such 'hairy' surfaces offer fascinating opportunities for addressing numerous problems of both academic and, in particular, industrial interest: high-quality, functional or protective coatings, composite materials, surface engineered particles, metal-organic interfaces, biological applications, micro-patterning, colloids, nanoparticles, functional devices, and many more. It is the desire of the authors that this book will be of benefit to readers who want to "brush-up on polymers".

  12. Broadly Applicable Nanowafer Drug Delivery System for Treating Eye Injuries

    Science.gov (United States)

    2015-09-01

    Systems in Systemic , Dermal, Transdermal , and Ocular Drug Delivery . Crit. Rev. Ther. Drug 2008, 25, 545–584. 14. Choy, Y. B.; Park, J.-H.; McCarey, B...AWARD NUMBER: W81XWH-13-1-0146 TITLE: Broadly Applicable Nanowafer Drug Delivery System for Treating Eye Injuries PRINCIPAL INVESTIGATOR: Dr...Broadly Applicable Nanowafer Drug Delivery System for Treating Eye Injuries” 5b. GRANT NUMBER W81XWH-13-1-0146 5c. PROGRAM ELEMENT NUMBER 6

  13. Design, Synthesis, and Applications of Carbon Nanohoops

    Science.gov (United States)

    2016-05-23

    rings via one electron reduction reactions was feasible. Therefore, the synthesis and spectroscopic investigations of these ring systems by reducing...Release; Distribution Unlimited UU UU UU UU 23-05-2016 15-Feb-2012 14-Feb-2016 Final Report: Design, Synthesis , and Applications of Carbon Nanohoops The...Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 Caron Nanohoops, paracyclophanes, carbon nanotubes, organic synthesis REPORT

  14. Nano materials Synthesis, Applications, and Toxicity 2012

    International Nuclear Information System (INIS)

    Nadagouda, M.N.; Lytle, D.A.; Speth, Th.F.; Dionysiou, D.D.; Mukhopadhyay, Sh.M.

    2013-01-01

    Nano technology presents new opportunities to create better materials and products. Nano materials find wide applications in catalysis, energy production, medicine, environmental remediation, automotive industry, and other sectors of our society. Nano material-containing products are already available globally and include automotive parts, defense application, drug delivery devices, coatings, computers, clothing, cosmetics, sports equipment, and medical devices. This special issue includes emerging advances in the field, with a special emphasis given to nano material synthesis and applications. There is an increasing interest in identifying magnetically separable catalysts for the degradation of wastewater. In this issue, A. Perumal et al. report an investigation of temperature-dependent magnetic properties and photo catalytic activity of CoFe 2 O 4 -Fe 3 O 4 magnetic nano composites (MNCs) synthesized by hydrothermal processes. These MNCs have saturation magnetization of 90 emu/g and coercivity (HC) of 530 Oe. The photo catalytic activity of the MNCs has been examined on the reduction of methyl orange (MO), a colored compound used in dyeing and printing textiles. The MNCs act as an excellent photo catalyst on the degradation of organic contaminants and degrade 93% of MO in 5 hours of UV irradiation. The photo catalytic activity of MNCs is attributed to remarkably high band gap energy and small particle size. Also, the MNCs with reproducible photo catalytic activity are easily separated from water media by applying an external magnetic field and they act as a promising catalyst for the remediation of textile wastewater. Microwaves can play an important role in orchestrating nano materials for a wide range of technological applications

  15. Graphene: from synthesis to engineering to biosensor applications

    Science.gov (United States)

    Singh, Jagpreet; Rathi, Aditi; Rawat, Mohit; Gupta, Manoj

    2018-03-01

    Graphene is a fascinating material of recent origin whose first isolation was being made possible through micromechanical cleavage of a graphite crystal. Owing to its fascinating properties, graphene has garnered significant attention in the research community for multiple applications. A number of methods have been employed for the synthesis of single-layer and multi-layer graphene. The extraordinary properties of graphene such as its Hall effect at room temperature, high surface area, tunable bandgap, high charge mobility and excellent electrical, conducting and thermal properties allow for the development of sensors of various types and also opened the doors for its use in nanoelectronics, supercapacitors and batteries. Biological aspects of graphene have also been investigated with particular emphasis on its toxicity and drug delivery. In this review, many of the salient aspects of graphene, such as from synthesis to its applications, primarily focusing on sensor applications which are of current interest, are covered.

  16. Nanodiamond and its application to drug delivery

    Directory of Open Access Journals (Sweden)

    Eiji Osawa

    2012-08-01

    Full Text Available Quasi-spherical diamond crystals having an average diameter of 3.7±0.6 nm are attracting much attention as an ideal material in carbon nanotechnology. In contrast to the other popular nanocarbons including fullerenes, carbon nanotubes and graphenes, our single-nanodiamond can be produced in uniform shape/size on industrial scale. Thus, the most serious problem in nanocarbon industry that persisted in the past 25 years, namely the technical failure to produce highly crystalline nanocarbons in narrow shape/size range does not exist in our diamond from the beginning. Among potential applications of the single-nanodiamond under development, this review concentrates on its highly promising role as a drug carrier, especially for therapeutic-resistant cancer. An interesting possibility of intercalation is proposed as the mechanism of drug transport through blood, which takes into accounts of the spontaneous formation of nanographene layer on the [111] facets, which is then extensively oxidized during oxidative soot removal process to give nanographene oxide partial surface, capable of intercalating drug molecules to prevent them from leaking and causing undesirable side effects during transportation to target malignant cells. A perspective of quantifying the drug delivery process by anticipating orders of magnitude in the number of administered detonation nanodiamond (DND particles is suggested.

  17. Hollow Micro-/Nanostructures: Synthesis and Applications

    KAUST Repository

    Lou, Xiong Wen (David); Archer, Lynden A.; Yang, Zichao

    2008-01-01

    for Portland cement, to produce concrete with enhanced strength and durability. This review is devoted to the progress made in the last decade in synthesis and applications of hollow micro-nanostructures. We present a comprehensive overview of synthetic

  18. Nanoparticle synthesis and delivery by an aerosol route for watermelon plant foliar uptake

    Science.gov (United States)

    Wang, Wei-Ning; Tarafdar, Jagadish C.; Biswas, Pratim

    2013-01-01

    An aerosol process was developed for synthesis and delivery of nanoparticles for living watermelon plant foliar uptake. This is an efficient technique capable of generating nanoparticles with controllable particle sizes and number concentrations. Aerosolized nanoparticles were easily applied to leaf surfaces and enter the stomata via gas uptake, avoiding direct interaction with soil systems, eliminating potential ecological risks. The uptake and transport of nanoparticles inside the watermelon plants were investigated systematically by various techniques, such as elemental analysis by inductively coupled plasma mass spectrometry and plant anatomy by transmission electron microscopy. The results revealed that certain fractions of nanoparticles ( d p watermelon plants. The particle size and number concentration played an important role in nanoparticle translocation inside the plants. In addition, the nanoparticle application method, working environment, and leaf structure are also important factors to be considered for successful plant foliar uptake.

  19. Surface active monomers synthesis, properties, and application

    CERN Document Server

    Borzenkov, Mykola

    2014-01-01

    This brief includes information on the background?of and development of synthesis of various types of surface active monomers. The authors explain the importance of utilization of surface active monomers for creation of surface active polymers? and the various biomedical applications of such compounds . This brief introduces techniques for the synthesis of novel types of surface active monomers, their colloidal and polymerizable properties and application for needs of medicine and biology.

  20. Applications of polymeric nanocapsules in field of drug delivery systems.

    Science.gov (United States)

    Rong, Xinyu; Xie, Yinghua; Hao, Xiaomei; Chen, Tao; Wang, Yingming; Liu, Yuanyuan

    2011-09-01

    Drug-loaded polymeric nanocapsules have exhibited potential applications in the field of drug delivery systems in recent years. This article entails the biodegradable polymers generally used for preparing nanocapsules, which include both natural polymers and synthetic polymers. Furthermore, the article presents a general review of the different preparation methods: nanoprecipitation method, emulsion-diffusion method, double emulsification method, emulsion-coacervation method, layer-by-layer assembly method. In addition, the analysis methods of nanocapsule characteristics, such as mean size, morphology, surface characteristics, shell thickness, encapsulation efficiency, active substance release, dispersion stability, are mentioned. Also, the applications of nanocapsules as carriers for use in drug delivery systems are reviewed, which primarily involve targeting drug delivery, controlled/sustained release drug delivery systems, transdermal drug delivery systems and improving stability and bioavailability of drugs. Nanocapsules, prepared with different biodegradable polymers, have received more and more attention and have been regarded as one of the most promising drug delivery systems.

  1. Synthesis of thermosensitive magnetic nanocarrier for controlled sorafenib delivery

    Energy Technology Data Exchange (ETDEWEB)

    Heidarinasab, Amir [Department of Chemical Engineering, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Ahmad Panahi, Homayon [Department of Chemistry, Central Tehran Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Faramarzi, Mehdi, E-mail: faramarzi.iaug@gmail.com [Department of Chemical Engineering, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Farjadian, Fatemeh [Pharmaceutical Sciences Research Center, Faculty of Pharmacy, Shiraz University of Medical Sciences, Shiraz (Iran, Islamic Republic of)

    2016-10-01

    Allyl glycidyl ether/N-isopropylacrylamide-grafted magnetic nanoparticles were prepared using silica-coated magnetic nanoparticles as a substrate for radical copolymerization of allyl glycidyl ether and N-isopropylacrylamide. Chitosan was coupled with the prepared nanoparticles by opening the epoxy ring of the allyl glycidyl ether. The thermosensitive magnetic nanocarrier (TSMNC) obtained can be applied as a potent drug carrier. The TSMNC structure was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and elemental analysis. Its morphology and size were investigated using field emission scanning electron microscopy, transmission electron microscopy and dynamic light scattering. The feasibility of employing the TSMNC for adsorption and in vitro controlled release of the chemotherapeutic agent sorafenib was tested. The effect of the adsorption parameters of pH, temperature, and loading time of sorafenib onto TSMNC was evaluated. The adsorption data was fitted to the Langmuir and Freundlich isotherms and the relevant parameters derived. The drug release profile indicated that 88% of the adsorbed drug was released within 35 h at 45 °C and drug release was Fickian diffusion-controlled. The results confirmed that the TSMNC has a high adsorption capacity at low temperature and good controlled release in a slow rate at a high temperature and could be developed for further application as a drug nanocarrier. - Graphical abstract: Magnetic nanoparticles were functionalized with chitosan and N-isopropylacrylamide. It was evaluated for sorafenib (SFB) adsorption and tested as a controlled-release system in response to changes in temperature. The TSMNC showed superparamagnetic properties with a high adsorption capacity and desirable controlled release at below and above LCST. Display Omitted - Highlights: • A TSMNC was synthesized for controlled

  2. Engineered nonviral nanocarriers for intracellular gene delivery applications

    International Nuclear Information System (INIS)

    Ojea-Jiménez, Isaac; Puntes, Victor F; Tort, Olivia; Lorenzo, Julia

    2012-01-01

    The efficient delivery of nucleic acids into mammalian cells is a central aspect of cell biology and of medical applications, including cancer therapy and tissue engineering. Non-viral chemical methods have been received with great interest for transfecting cells. However, further development of nanocarriers that are biocompatible, efficient and suitable for clinical applications is still required. In this paper, the different material platforms for gene delivery are comparatively addressed, and the mechanisms of interaction with biological systems are discussed carefully. (paper)

  3. Biodegradable multiblock copolymers for drug delivery applications

    NARCIS (Netherlands)

    van Dijkhuizen-Radersma, Riemke

    2004-01-01

    With rapid advances in genomic research and biotechnology, an increasing number of pharmaceutical proteins and peptides become available for a variety of diseases. However, the efficient delivery of these drugs is hampered by their large size and (biological) instability. Consequently, to obtain a

  4. Albumin and its application in drug delivery.

    Science.gov (United States)

    Sleep, Darrell

    2015-05-01

    Rapid clearance of drugs from the body results in short therapeutic half-life and is an integral property of many protein and peptide-based drugs. To maintain the desired therapeutic effect patients are required to administer higher doses more frequently, which is inconvenient and risks undesirable side effects. Drug delivery technologies aim to minimise the number of administrations and dose-related toxicity while maximising therapeutic efficacy. This review describes albumin's inherent biochemical and biophysical properties, which make it an attractive drug delivery platform and the developmental status of drugs that are associated, conjugated or genetically fused with albumin. Albumin interacts with a number of cell surface receptors including gp18, gp30, gp60, FcRn, cubilin and megalin. The importance of albumin's interaction with the FcRn receptor, the basis for albumin's long circulatory half-life, is described, as are engineered albumins with improved pharmacokinetics. Albumin naturally accumulates at tumours and sites of inflammation, a characteristic which can be augmented by the addition of targeting ligands. The development of albumin drug conjugates which reply upon this property is described. Albumin's inherent biochemical and biophysical properties make it an ideal drug delivery platform. Recent advances in our understanding of albumin physiology and the improvement in albumin-based therapies strongly suggest that albumin-based therapies have a significant advantage over alternative technologies in terms of half-life, stability, versatility, safety and ease of manufacture. Given the importance of the albumin:FcRn interaction, the interpretation of the pharmacokinetic and pharmacodynamic profiles of albumin-based therapeutics with disturbed albumin:FcRn interaction may have to be reassessed. The FcRn receptor has additional functionality, especially in relation to immunology, antigen presentation and delivery of proteins across mucosal membranes

  5. Functionalization of protein-based nanocages for drug delivery applications.

    Science.gov (United States)

    Schoonen, Lise; van Hest, Jan C M

    2014-07-07

    Traditional drug delivery strategies involve drugs which are not targeted towards the desired tissue. This can lead to undesired side effects, as normal cells are affected by the drugs as well. Therefore, new systems are now being developed which combine targeting functionalities with encapsulation of drug cargo. Protein nanocages are highly promising drug delivery platforms due to their perfectly defined structures, biocompatibility, biodegradability and low toxicity. A variety of protein nanocages have been modified and functionalized for these types of applications. In this review, we aim to give an overview of different types of modifications of protein-based nanocontainers for drug delivery applications.

  6. Drug delivery and nanoparticles: Applications and hazards

    Directory of Open Access Journals (Sweden)

    Wim H De Jong

    2008-06-01

    Full Text Available Wim H De Jong1, Paul JA Borm2,31Laboratory for Toxicology, Pathology and Genetics, National Institute for Public Health and the Environment (RIVM, Bilthoven, The Netherlands; 2Zuyd University, Centre of Expertise in Life Sciences, Heerlen, The Netherlands; 3Magnamedics GmbH, Aachen, GermanyAbstract: The use of nanotechnology in medicine and more specifically drug delivery is set to spread rapidly. Currently many substances are under investigation for drug delivery and more specifically for cancer therapy. Interestingly pharmaceutical sciences are using nanoparticles to reduce toxicity and side effects of drugs and up to recently did not realize that carrier systems themselves may impose risks to the patient. The kind of hazards that are introduced by using nanoparticles for drug delivery are beyond that posed by conventional hazards imposed by chemicals in classical delivery matrices. For nanoparticles the knowledge on particle toxicity as obtained in inhalation toxicity shows the way how to investigate the potential hazards of nanoparticles. The toxicology of particulate matter differs from toxicology of substances as the composing chemical(s may or may not be soluble in biological matrices, thus influencing greatly the potential exposure of various internal organs. This may vary from a rather high local exposure in the lungs and a low or neglectable exposure for other organ systems after inhalation. However, absorbed species may also influence the potential toxicity of the inhaled particles. For nanoparticles the situation is different as their size opens the potential for crossing the various biological barriers within the body. From a positive viewpoint, especially the potential to cross the blood brain barrier may open new ways for drug delivery into the brain. In addition, the nanosize also allows for access into the cell and various cellular compartments including the nucleus. A multitude of substances are currently under investigation

  7. Photopolymerization Synthesis of Magnetic Nanoparticle Embedded Nanogels for Targeted Biotherapeutic Delivery

    Science.gov (United States)

    Denmark, Daniel J.

    materials. Herein, a low-cost, scalable, and rapid, custom ultraviolet photo-reactor with in-situ, spectroscopic monitoring system is used to observe the synthesis as the sample undergoes photopolymerization. This method also allows in-situ encapsulation of the magnetic nanoparticles simplifying the process. Size characterization of the resulting nanogels was performed by Transmission Electron Microscopy revealing size-tunable nanogel spheres between 50 and 800 nm by varying the ratio and concentration of the reactants. Nano-Tracking Analysis indicates that the nanogels exhibit minimal agglomeration as well as provides a temperature-dependent particle size distribution. Optical characterization utilized Fourier Transform Infrared and Ultraviolet Spectroscopy to confirm successful polymerization. When samples of the nanogels encapsulating magnetic nanoparticles were subjected to an alternating magnetic field a temperature increase was observed indicating that triggered release is possible. Furthermore, a model, based on linear response theory that innovatively utilizes size distribution data, is presented to explain alternating magnetic field heating results. The results presented here will advance targeted biotherapeutic delivery and have a wide range of applications in medical sciences like oncology, gene delivery, cardiology and endocrinology.

  8. Recent progress on fabrication and drug delivery applications of nanostructured hydroxyapatite.

    Science.gov (United States)

    Mondal, Sudip; Dorozhkin, Sergy V; Pal, Umapada

    2018-07-01

    Through this brief review, we provide a comprehensive historical background of the development of nanostructured hydroxyapatite (nHAp), and its application potentials for controlled drug delivery, drug conjugation, and other biomedical treatments. Aspects associated with efficient utilization of hydroxyapatite (HAp) nanostructures such as their synthesis, interaction with drug molecules, and other concerns, which need to be resolved before they could be used as a potential drug carrier in body system, are discussed. This review focuses on the evolution of perceptions, practices, and accomplishments in providing improved delivery systems for drugs until date. The pioneering developments that have presaged today's fascinating state of the art drug delivery systems based on HAp and HAp-based composite nanostructures are also discussed. Special emphasis has been given to describe the application and effectiveness of modified HAp as drug carrier agent for different diseases such as bone-related disorders, carriers for antibiotics, anti-inflammatory, carcinogenic drugs, medical imaging, and protein delivery agents. As only a very few published works made comprehensive evaluation of HAp nanostructures for drug delivery applications, we try to cover the three major areas: concepts, practices and achievements, and applications, which have been consolidated and patented for their practical usage. The review covers a broad spectrum of nHAp and HAp modified inorganic drug carriers, emphasizing some of their specific aspects those needed to be considered for future drug delivery applications. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Therapeutic Approaches and Drug Discovery > Nanomedicine for Respiratory Disease Nanotechnology Approaches to Biology > Cells at the Nanoscale. © 2017 Wiley Periodicals, Inc.

  9. Transdermal microneedles for drug delivery applications

    International Nuclear Information System (INIS)

    Teo, Ai Ling; Shearwood, Christopher; Ng, Kian Chye; Lu Jia; Moochhala, Shabbir

    2006-01-01

    Transdermal drug delivery (TDD) has many advantages, the main one being the ability to maintain the prolonged release of drugs to attain optimal blood concentrations. Unfortunately, nature has provided a very effective protective barrier, the stratum corneum (sc), which limits TDD to certain types of drugs with specific properties. In order to enhance TDD, the idea of using microneedles to painlessly penetrate the sc barrier has previously been proposed. In this paper, we will review the different microneedles that are currently being developed as well as our own efforts in this area. Based on our experiences, we will offer our view on the key parameters for effective transdermal microneedle design as well as future directions in this area

  10. Transdermal microneedles for drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Teo, Ai Ling [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117510 (Singapore); Shearwood, Christopher [School of Mechanical and Aerospace Engineering, 50 Nanyang Avenue, Singapore 639798 (Singapore); Ng, Kian Chye [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117510 (Singapore); Lu Jia [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117510 (Singapore); Moochhala, Shabbir [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117510 (Singapore)]. E-mail: mshabbir@dso.org.sg

    2006-07-25

    Transdermal drug delivery (TDD) has many advantages, the main one being the ability to maintain the prolonged release of drugs to attain optimal blood concentrations. Unfortunately, nature has provided a very effective protective barrier, the stratum corneum (sc), which limits TDD to certain types of drugs with specific properties. In order to enhance TDD, the idea of using microneedles to painlessly penetrate the sc barrier has previously been proposed. In this paper, we will review the different microneedles that are currently being developed as well as our own efforts in this area. Based on our experiences, we will offer our view on the key parameters for effective transdermal microneedle design as well as future directions in this area.

  11. Synthesis and Application of Graphene Based Nanomaterials

    Science.gov (United States)

    Peng, Zhiwei

    Graphene, a two-dimensional sp2-bonded carbon material, has recently attracted major attention due to its excellent electrical, optical and mechanical properties. Depending on different applications, graphene and its derived hybrid nanomaterials can be synthesized by either bottom-up chemical vapor deposition (CVD) methods for electronics, or various top-down chemical reaction methods for energy generation and storage devices. My thesis begins with the investigation of CVD synthesis of graphene thin films in Chapter 1, including the direct growth of bilayer graphene on insulating substrates and synthesis of "rebar graphene": a hybrid structure with graphene and carbon or boron nitride nanotubes. Chapter 2 discusses the synthesis of nanoribbon-shaped materials and their applications, including splitting of vertically aligned multi-walled carbon nanotube carpets for supercapacitors, synthesis of dispersable ferromagnetic graphene nanoribbon stacks with enhanced electrical percolation properties in magnetic field, graphene nanoribbon/SnO 2 nanocomposite for lithium ion batteries, and enhanced electrocatalysis for hydrogen evolution reactions from WS2 nanoribbons. Next, Chapter 3 discusses graphene coated iron oxide nanomaterials and their use in energy storage applications. Finally, Chapter 4 introduces the development, characterization, and fabrication of laser induced graphene and its application as supercapacitors.

  12. Applications of covalent organic frameworks (COFs): From gas storage and separation to drug delivery

    Institute of Scientific and Technical Information of China (English)

    Ming-Xue Wu; Ying-Wei Yang

    2017-01-01

    Covalent organic frameworks (COFs) are an emerging class of porous covalent organic structures whose backbones were composed of light elements (B,C,N,O,Si) and linked by robust covalent bonds to endow such material with desirable properties,i.e.,inherent porosity,well-defined pore aperture,ordered channel structure,large surface area,high stability,and multi-dimension.As expected,the abovementioned properties of COFs broaden the applications of this class of materials in various fields such as gas storage and separation,catalysis,optoelectronics,sensing,small molecules adsorption,and drug delivery.In this review,we outlined the synthesis of COFs and highlighted their applications ranging from the initial gas storage and separation to drug delivery.

  13. Application of nanohydrogels in drug delivery systems: recent patents review.

    Science.gov (United States)

    Dalwadi, Chintan; Patel, Gayatri

    2015-01-01

    Nanohydrogel combines the advantages of hydrogel and nano particulate systems. Similar to the hydrogel and macrogel, nanohydrogel can protect the drug and control drug release by stimuli responsive conformation or biodegradable bond into the polymer networks. Nanohydrogel has drawn huge interest due to their potential applications, such as carrier in target-specific controlled drug delivery, absorbents, chemical/biological sensors, and bio-mimetic materials. Similar to the nanoparticles, stimuli responsive nanohydrogel can easily be delivered in the liquid form for parenteral drug delivery application. This review highlights the methods to prepare nanohydrogel based on natural and synthetic polymers for diverse applications in drug delivery. It also encompasses the drug loading and drug release mechanism of the nanohydrogel formulation and patents related to the composition and chemical methods for preparation of nanohydrogel formulation with current status in clinical trials.

  14. Fluid Delivery System For Capillary Electrophoretic Applications.

    Science.gov (United States)

    Li, Qingbo; Liu, Changsheng; Kane, Thomas E.; Kernan, John R.; Sonnenschein, Bernard; Sharer, Michael V.

    2002-04-23

    An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.

  15. Self-Assembled Hydrogel Nanoparticles for Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Miguel Gama

    2010-02-01

    Full Text Available Hydrogel nanoparticles—also referred to as polymeric nanogels or macromolecular micelles—are emerging as promising drug carriers for therapeutic applications. These nanostructures hold versatility and properties suitable for the delivery of bioactive molecules, namely of biopharmaceuticals. This article reviews the latest developments in the use of self-assembled polymeric nanogels for drug delivery applications, including small molecular weight drugs, proteins, peptides, oligosaccharides, vaccines and nucleic acids. The materials and techniques used in the development of self-assembling nanogels are also described.

  16. 3D printing applications for transdermal drug delivery.

    Science.gov (United States)

    Economidou, Sophia N; Lamprou, Dimitrios A; Douroumis, Dennis

    2018-06-15

    The role of two and three-dimensional printing as a fabrication technology for sophisticated transdermal drug delivery systems is explored in literature. 3D printing encompasses a family of distinct technologies that employ a virtual model to produce a physical object through numerically controlled apparatuses. The applicability of several printing technologies has been researched for the direct or indirect printing of microneedle arrays or for the modification of their surface through drug-containing coatings. The findings of the respective studies are presented. The range of printable materials that are currently used or potentially can be employed for 3D printing of transdermal drug delivery (TDD) systems is also reviewed. Moreover, the expected impact and challenges of the adoption of 3D printing as a manufacturing technique for transdermal drug delivery systems, are assessed. Finally, this paper outlines the current regulatory framework associated with 3D printed transdermal drug delivery systems. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Application of polymeric nanoparticles and micelles in insulin oral delivery

    Directory of Open Access Journals (Sweden)

    Milind Sadashiv Alai

    2015-09-01

    Full Text Available Diabetes mellitus is an endocrine disease in which the pancreas does not produce sufficient insulin or the body cannot effectively use the insulin it produces. Insulin therapy has been the best choice for the clinical management of diabetes mellitus. The current insulin therapy is via subcutaneous injection, which often fails to mimic the glucose homeostasis that occurs in normal individuals. This provokes numerous attempts to develop a safe and effective noninvasive route for insulin delivery. Oral delivery is the most convenient administration route. However, insulin cannot be well absorbed orally because of its rapid enzymatic degradation in the gastrointestinal tract. Therefore, nanoparticulate carriers such as polymeric nanoparticles and micelles are employed for the oral delivery of insulin. These nanocarriers protect insulin from degradation and facilitate insulin uptake via a transcellular and/or paracellular pathway. This review article focuses on the application of nanoparticles and micelles in insulin oral delivery. The recent advances in this topic are also reviewed.

  18. MICROWAVE TECHNOLOGY CHEMICAL SYNTHESIS APPLICATIONS

    Science.gov (United States)

    Microwave-accelerated chemical syntheses in various solvents as well as under solvent-free conditions have witnessed an explosive growth. The technique has found widespread application predominantly exploiting the inexpensive unmodified household microwave (MW) ovens although th...

  19. Photocatalytic semiconductors synthesis, characterization, and environmental applications

    CERN Document Server

    Hernández-Ramírez, Aracely

    2014-01-01

    This critical volume examines the different methods used for the synthesis of a great number of photocatalysts, including TiO2, ZnO and other modified semiconductors, as well as characterization techniques used for determining the optical, structural and morphological properties of the semiconducting materials. Additionally, the authors discuss photoelectrochemical methods for determining the light activity of the photocatalytic semiconductors by means of measurement of properties such as band gap energy, flat band potential and kinetics of hole and electron transfer. Photocatalytic Semiconductors: Synthesis, Characterization and Environmental Applications provide an overview of the semiconductor materials from first- to third-generation photocatalysts and their applications in wastewater treatment and water disinfection. The book further presents economic and toxicological aspects in the production and application of photocatalytic materials.

  20. Asymmetric synthesis II more methods and applications

    CERN Document Server

    Christmann, Mathias

    2012-01-01

    After the overwhelming success of 'Asymmetric Synthesis - The Essentials', narrating the colorful history of asymmetric synthesis, this is the second edition with latest subjects and authors. While the aim of the first edition was mainly to honor the achievements of the pioneers in asymmetric syntheses, the aim of this new edition was bringing the current developments, especially from younger colleagues, to the attention of students. The format of the book remained unchanged, i.e. short conceptual overviews by young leaders in their field including a short biography of the authors. The growing multidisciplinary research within chemistry is reflected in the selection of topics including metal catalysis, organocatalysis, physical organic chemistry, analytical chemistry, and its applications in total synthesis. The prospective reader of this book is a graduate or undergraduate student of advanced organic chemistry as well as the industrial chemist who wants to get a brief update on the current developments in th...

  1. Nanoparticle synthesis and delivery by an aerosol route for watermelon plant foliar uptake

    International Nuclear Information System (INIS)

    Wang Weining; Tarafdar, Jagadish C.; Biswas, Pratim

    2013-01-01

    An aerosol process was developed for synthesis and delivery of nanoparticles for living watermelon plant foliar uptake. This is an efficient technique capable of generating nanoparticles with controllable particle sizes and number concentrations. Aerosolized nanoparticles were easily applied to leaf surfaces and enter the stomata via gas uptake, avoiding direct interaction with soil systems, eliminating potential ecological risks. The uptake and transport of nanoparticles inside the watermelon plants were investigated systematically by various techniques, such as elemental analysis by inductively coupled plasma mass spectrometry and plant anatomy by transmission electron microscopy. The results revealed that certain fractions of nanoparticles (d p < 100 nm) generated by the aerosol process could enter the leaf following the stomatal pathway, then pass through the stem, and reach the root of the watermelon plants. The particle size and number concentration played an important role in nanoparticle translocation inside the plants. In addition, the nanoparticle application method, working environment, and leaf structure are also important factors to be considered for successful plant foliar uptake.

  2. Nanoparticle synthesis and delivery by an aerosol route for watermelon plant foliar uptake

    Energy Technology Data Exchange (ETDEWEB)

    Wang Weining [Washington University in St. Louis, Aerosol and Air Quality Research Laboratory, Department of Energy, Environmental and Chemical Engineering (United States); Tarafdar, Jagadish C. [Central Arid Zone Research Institute (India); Biswas, Pratim, E-mail: pbiswas@wustl.edu [Washington University in St. Louis, Aerosol and Air Quality Research Laboratory, Department of Energy, Environmental and Chemical Engineering (United States)

    2013-01-15

    An aerosol process was developed for synthesis and delivery of nanoparticles for living watermelon plant foliar uptake. This is an efficient technique capable of generating nanoparticles with controllable particle sizes and number concentrations. Aerosolized nanoparticles were easily applied to leaf surfaces and enter the stomata via gas uptake, avoiding direct interaction with soil systems, eliminating potential ecological risks. The uptake and transport of nanoparticles inside the watermelon plants were investigated systematically by various techniques, such as elemental analysis by inductively coupled plasma mass spectrometry and plant anatomy by transmission electron microscopy. The results revealed that certain fractions of nanoparticles (d{sub p} < 100 nm) generated by the aerosol process could enter the leaf following the stomatal pathway, then pass through the stem, and reach the root of the watermelon plants. The particle size and number concentration played an important role in nanoparticle translocation inside the plants. In addition, the nanoparticle application method, working environment, and leaf structure are also important factors to be considered for successful plant foliar uptake.

  3. Hydroxyapatite-ciprofloxacin delivery system: Synthesis, characterisation and antibacterial activity

    Directory of Open Access Journals (Sweden)

    Ciocilteu Maria-Viorica

    2018-06-01

    Full Text Available The main objective of this study was to synthesize hydroxyapatite-ciprofloxacin composites using a chemical precipitation method and to evaluate the properties and in vitro release profile of the drug from the hydroxyapatite-ciprofloxacin composites. Composite characterization was achieved by FT-IR, XRD and DLS. Ciprofloxacin determination was accomplished by HPLC, resulting in good incorporation efficiency of the drug (18.13 %. The in vitro release study (Higuchi model C = K t1/2 and Ritger-Peppas model, C = K t0.6 showed a diffusion-controlled mechanism. The antibacterial activity showed that the bacterial growth inhibition zones were approximately equal for the synthesis composites and for the mechanical mixture on the Staphylococcus aureus germ.

  4. Synthesis, toxicity, biocompatibility, and biomedical applications of graphene and graphene-related materials

    Directory of Open Access Journals (Sweden)

    Gurunathan S

    2016-05-01

    Full Text Available Sangiliyandi Gurunathan, Jin-Hoi Kim Stem Cell and Regenerative Biology, Konkuk University, Seoul, Republic of Korea Abstract: Graphene is a two-dimensional atomic crystal, and since its development it has been applied in many novel ways in both research and industry. Graphene possesses unique properties, and it has been used in many applications including sensors, batteries, fuel cells, supercapacitors, transistors, components of high-strength machinery, and display screens in mobile devices. In the past decade, the biomedical applications of graphene have attracted much interest. Graphene has been reported to have antibacterial, antiplatelet, and anticancer activities. Several salient features of graphene make it a potential candidate for biological and biomedical applications. The synthesis, toxicity, biocompatibility, and biomedical applications of graphene are fundamental issues that require thorough investigation in any kind of applications related to human welfare. Therefore, this review addresses the various methods available for the synthesis of graphene, with special reference to biological synthesis, and highlights the biological applications of graphene with a focus on cancer therapy, drug delivery, bio-imaging, and tissue engineering, together with a brief discussion of the challenges and future perspectives of graphene. We hope to provide a comprehensive review of the latest progress in research on graphene, from synthesis to applications. Keywords: biomedical applications, cancer therapy, drug delivery, graphene, graphene-related materials, tissue engineering, toxicity 

  5. Aminooxylated Carbohydrates: Synthesis and Applications.

    Science.gov (United States)

    Pifferi, Carlo; Daskhan, Gour Chand; Fiore, Michele; Shiao, Tze Chieh; Roy, René; Renaudet, Olivier

    2017-08-09

    Among other classes of biomolecules, carbohydrates and glycoconjugates are widely involved in numerous biological functions. In addition to addressing the related synthetic challenges, glycochemists have invested intense efforts in providing access to structures that can be used to study, activate, or inhibit these biological processes. Over the past few decades, aminooxylated carbohydrates have been found to be key building blocks for achieving these goals. This review provides the first in-depth overview covering several aspects related to the syntheses and applications of aminooxylated carbohydrates. After a brief introduction to oxime bonds and their relative stabilities compared to related C═N functions, synthetic aspects of oxime ligation and methodologies for introducing the aminooxy functionality onto both glycofuranosyls and glycopyranosyls are described. The subsequent section focuses on biological applications involving aminooxylated carbohydrates as components for the construcion of diverse architectures. Mimetics of natural structures represent useful tools for better understanding the features that drive carbohydrate-receptor interaction, their biological output and they also represent interesting structures with improved stability and tunable properties. In the next section, multivalent structures such as glycoclusters and glycodendrimers obtained through oxime ligation are described in terms of synthetic design and their biological applications such as immunomodulators. The second-to-last section discusses miscellaneous applications of oxime-based glycoconjugates, such as enantioselective catalysis and glycosylated oligonucleotides, and conclusions and perspectives are provided in the last section.

  6. Encapsulation systems for the delivery of hydrophilic nutraceuticals: Food application.

    Science.gov (United States)

    Aditya, N P; Espinosa, Yadira Gonzalez; Norton, Ian T

    2017-07-01

    Increased health risk associated with the sedentary life style is forcing the food manufacturers to look for food products with specific or general health benefits e.g. beverages enriched with nutraceuticals like catechin, curcumin rutin. Compounds like polyphenols, flavonoids, vitamins are the good choice of bioactive compounds that can be used to fortify the food products to enhance their functionality. However due to low stability and bioavailability of these bioactives (both hydrophobic and hydrophilic) within the heterogeneous food microstructure and in the Gastro Intestinal Tract (GIT), it becomes extremely difficult to pass on the real health benefits to the consumers. Recent developments in the application of nano-delivery systems for food product development is proving to be a game changer which has raised the expectations of the researchers, food manufacturers and consumers regarding possibility of enhancing the functionality of bioactives within the fortified food products. In this direction, nano/micro delivery systems using lipids, surfactants and other materials (carbohydrates, polymers, complexes, protein) have been fabricated to stabilize and enhance the biological activity of the bioactive compounds. In the present review, current status of the various delivery systems that are used for the delivery of hydrophilic bioactives and future prospects for using other delivery systems that have been not completely explored for the delivery of hydrophilic bioactives e.g. niosomes; bilosomes, cubosomes are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Discovery of Antibiotics-derived Polymers for Gene Delivery using Combinatorial Synthesis and Cheminformatics Modeling

    Science.gov (United States)

    Potta, Thrimoorthy; Zhen, Zhuo; Grandhi, Taraka Sai Pavan; Christensen, Matthew D.; Ramos, James; Breneman, Curt M.; Rege, Kaushal

    2014-01-01

    We describe the combinatorial synthesis and cheminformatics modeling of aminoglycoside antibiotics-derived polymers for transgene delivery and expression. Fifty-six polymers were synthesized by polymerizing aminoglycosides with diglycidyl ether cross-linkers. Parallel screening resulted in identification of several lead polymers that resulted in high transgene expression levels in cells. The role of polymer physicochemical properties in determining efficacy of transgene expression was investigated using Quantitative Structure-Activity Relationship (QSAR) cheminformatics models based on Support Vector Regression (SVR) and ‘building block’ polymer structures. The QSAR model exhibited high predictive ability, and investigation of descriptors in the model, using molecular visualization and correlation plots, indicated that physicochemical attributes related to both, aminoglycosides and diglycidyl ethers facilitated transgene expression. This work synergistically combines combinatorial synthesis and parallel screening with cheminformatics-based QSAR models for discovery and physicochemical elucidation of effective antibiotics-derived polymers for transgene delivery in medicine and biotechnology. PMID:24331709

  8. Polyfuran Conducting Polymers: Synthesis, Properties, and Applications.

    OpenAIRE

    González-Tejera, M.J.; Sánchez de la Blanca, Emilia; Carrillo Ramiro, Isabel

    2008-01-01

    In this review, polyfuran (PFu) synthesis methods and the nucleation mechanism; the electrochemical, structural, morphological, and magnetic properties of PFu; thermal behavior; theoretical calculations on PFu, as well as its applications reported to date, have been compiled. Not only PFu homopolymers have been reviewed, but also PFu co-polymers, PFu bipolymers, and PFu composites. The results are listed, discussed, and compared. It is hoped that this assembly of all the relevant data might e...

  9. Nanodiamonds of Laser Synthesis for Biomedical Applications.

    Science.gov (United States)

    Perevedentseva, E; Peer, D; Uvarov, V; Zousman, B; Levinson, O

    2015-02-01

    In recent decade detonation nanodiamonds (DND), discovered 50 years ago and used in diverse technological processes, have been actively applied in biomedical research as a drug and gene delivery carrier, a contrast agent for bio-imaging and diagnostics and an adsorbent for protein separation and purification. In this work we report about nanodiamonds of high purity produced by laser assisted technique, compare them with DND and consider the prospect and advantages of their use in the said applications.

  10. Magnetite Nanoparticles Coated with Rifampicin and Chlortetracycline for Drug Delivery Applications

    International Nuclear Information System (INIS)

    Nadejde, Claudia; Ciurlica, Ecaterina Foca-nici; Creanga, Dorina; Carlescu, Aurelian; Badescu, Vasile

    2010-01-01

    Four types of biocompatible magnetic fluids based on superparamagnetic nanoparticles with Fe 3 O 4 cores were functionalized with antibiotics (rifampicin or chlortetracycline) as potential candidates for in vivo biomedical applications, such as magnetically controlled drug delivery. The synthesis consisted in coprecipitation of iron oxide in basic, as well as in acid medium, followed by the dispersion of the resulted magnetite nanoparticles in aqueous solution containing the antibiotic. The chosen method to prepare the magnetite-core/drug-shell systems avoided intermediate organic coating of the magnetic nanoparticles. Comparative analysis of the rheological features of the aqueous magnetic fluid samples was performed. The structural features of the coated magnetic particles were investigated by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometry (VSM). Good crystallinity and adequate stability in time were evidenced. Drug delivery curves were spectrophotometrically provided.

  11. Dendrimers as tunable vectors of drug delivery systems and biomedical and ocular applications

    Science.gov (United States)

    Kalomiraki, Marina; Thermos, Kyriaki; Chaniotakis, Nikos A

    2016-01-01

    Dendrimers are large polymeric structures with nanosize dimensions (1–10 nm) and unique physicochemical properties. The major advantage of dendrimers compared with linear polymers is their spherical-shaped structure. During synthesis, the size and shape of the dendrimer can be customized and controlled, so the finished macromolecule will have a specific “architecture” and terminal groups. These characteristics will determine its suitability for drug delivery, diagnostic imaging, and as a genetic material carrier. This review will focus initially on the unique properties of dendrimers and their use in biomedical applications, as antibacterial, antitumor, and diagnostic agents. Subsequently, emphasis will be given to their use in drug delivery for ocular diseases. PMID:26730187

  12. Dendrimers as tunable vectors of drug delivery systems and biomedical and ocular applications

    Directory of Open Access Journals (Sweden)

    Kalomiraki M

    2015-12-01

    Full Text Available Marina Kalomiraki,1 Kyriaki Thermos,2 Nikos A Chaniotakis1 1Laboratory of Analytical Chemistry, Department of Chemistry, 2Department of Pharmacology, School of Medicine, University of Crete Voutes, Heraklion, Greece Abstract: Dendrimers are large polymeric structures with nanosize dimensions (1–10 nm and unique physicochemical properties. The major advantage of dendrimers compared with linear polymers is their spherical-shaped structure. During synthesis, the size and shape of the dendrimer can be customized and controlled, so the finished macromolecule will have a specific “architecture” and terminal groups. These characteristics will determine its suitability for drug delivery, diagnostic imaging, and as a genetic material carrier. This review will focus initially on the unique properties of dendrimers and their use in biomedical applications, as antibacterial, antitumor, and diagnostic agents. Subsequently, emphasis will be given to their use in drug delivery for ocular diseases. Keywords: nanoparticles, ocular diseases, encapsulation, macromolecule, diagnostic agent

  13. Review on the progress in synthesis and application of magnetic carbon nanocomposites

    Science.gov (United States)

    Zhu, Maiyong; Diao, Guowang

    2011-07-01

    This review focuses on the synthesis and application of nanostructured composites containing magnetic nanostructures and carbon-based materials. Great progress in fabrication of magnetic carbon nanocomposites has been made by developing methods including filling process, template-based synthesis, chemical vapor deposition, hydrothermal/solvothermal method, pyrolysis procedure, sol-gel process, detonation induced reaction, self-assembly method, etc. The applications of magnetic carbon nanocomposites expanded to a wide range of fields such as environmental treatment, microwave absorption, magnetic recording media, electrochemical sensor, catalysis, separation/recognization of biomolecules and drug delivery are discussed. Finally, some future trends and perspectives in this research area are outlined.

  14. Graphene optoelectronics synthesis, characterization, properties, and applications

    CERN Document Server

    bin M Yusoff, Abdul Rashid

    2014-01-01

    This first book on emerging applications for this innovative material gives an up-to-date account of the many opportunities graphene offers high-end optoelectronics.The text focuses on potential as well as already realized applications, discussing metallic and passive components, such as transparent conductors and smart windows, as well as high-frequency devices, spintronics, photonics, and terahertz devices. Also included are sections on the fundamental properties, synthesis, and characterization of graphene. With its unique coverage, this book will be welcomed by materials scientists, solid-

  15. Polypeptide nanogels with hydrophobic moieties in the cross-linked ionic cores: Synthesis, characterization and implications for anticancer drug delivery

    Science.gov (United States)

    Kim, Jong Oh; Oberoi, Hardeep S.; Desale, Swapnil; Kabanov, Alexander V.; Bronich, Tatiana K.

    2014-01-01

    Polymer nanogels have gained considerable attention as a potential platform for drug delivery applications. Here we describe the design and synthesis of novel polypeptide-based nanogels with hydrophobic moieties in the cross-linked ionic cores. Diblock copolymer, poly(ethylene glycol)-b-poly(L-glutamic acid), hydrophobically modified with L-phenylalanine methyl ester moieties was used for controlled template synthesis of nanogels with small size (ca. 70 nm in diameter) and narrow particle size distribution. Steady-state and time-resolved fluorescence studies using coumarin C153 indicated the existence of hydrophobic domains in the ionic cores of the nanogels. Stable doxorubicin-loaded nanogels were prepared at high drug capacity (30 w/w%). We show that nanogels are enzymatically-degradable leading to accelerated drug release under simulated lysosomal acidic pH. Furthermore, we demonstrate that the nanogel-based formulation of doxorubicin is well tolerated and exhibit an improved antitumor activity compared to a free doxorubicin in an ovarian tumor xenograft mouse model. Our results signify the point to a potential of these biodegradable nanogels as attractive carriers for delivery of chemotherapeutics. PMID:23998716

  16. Submicron Emulsions and Their Applications in Oral Delivery.

    Science.gov (United States)

    Mundada, Veenu; Patel, Mitali; Sawant, Krutika

    2016-01-01

    A "submicron emulsion" is an isotropic mixture of drug, lipids, and surfactants, usually with hydrophilic cosolvents and with droplet diameters ranging from 10 to 500 nm. Submicron emulsions are of increasing interest in medicine due to their kinetic stability, high solubilizing capacity, and tiny globule size. Because of these properties, they have been applied in various fields, such as personal care, cosmetics, health care, pharmaceuticals, and agrochemicals. Submicron emulsions are by far the most advanced nanoparticulate systems for the systemic delivery of biologically active agents for controlled drug delivery and targeting. They are designed mainly for pharmaceutical formulations suitable for various routes of administration like parenteral, ocular, transdermal, and oral. This review article describes the marked potential of submicron emulsions for oral drug delivery owing to their numerous advantages like reduced first pass metabolism, inhibition of P-glycoprotein efflux system, and enhanced absorption via intestinal lymphatic pathway. To overcome the limitations of liquid dosage forms, submicron emulsions can be formulated into solid dosage forms such as solid self-emulsifying systems. This article covers various types of submicron emulsions like microemulsion, nanoemulsion, and self-emulsifying drug delivery system (SEDDS), and their potential pharmaceutical applications in oral delivery with emphasis on their advantages, limitations, and advancements.

  17. Chitosan for gene delivery and orthopedic tissue engineering applications.

    Science.gov (United States)

    Raftery, Rosanne; O'Brien, Fergal J; Cryan, Sally-Ann

    2013-05-15

    Gene therapy involves the introduction of foreign genetic material into cells in order exert a therapeutic effect. The application of gene therapy to the field of orthopaedic tissue engineering is extremely promising as the controlled release of therapeutic proteins such as bone morphogenetic proteins have been shown to stimulate bone repair. However, there are a number of drawbacks associated with viral and synthetic non-viral gene delivery approaches. One natural polymer which has generated interest as a gene delivery vector is chitosan. Chitosan is biodegradable, biocompatible and non-toxic. Much of the appeal of chitosan is due to the presence of primary amine groups in its repeating units which become protonated in acidic conditions. This property makes it a promising candidate for non-viral gene delivery. Chitosan-based vectors have been shown to transfect a number of cell types including human embryonic kidney cells (HEK293) and human cervical cancer cells (HeLa). Aside from its use in gene delivery, chitosan possesses a range of properties that show promise in tissue engineering applications; it is biodegradable, biocompatible, has anti-bacterial activity, and, its cationic nature allows for electrostatic interaction with glycosaminoglycans and other proteoglycans. It can be used to make nano- and microparticles, sponges, gels, membranes and porous scaffolds. Chitosan has also been shown to enhance mineral deposition during osteogenic differentiation of MSCs in vitro. The purpose of this review is to critically discuss the use of chitosan as a gene delivery vector with emphasis on its application in orthopedic tissue engineering.

  18. 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.

  19. Carbon nanotubes from synthesis to in vivo biomedical applications.

    Science.gov (United States)

    Sajid, Muhammad Imran; Jamshaid, Usama; Jamshaid, Talha; Zafar, Nadiah; Fessi, H; Elaissari, Abdelhamid

    2016-03-30

    Owing to their unique and interesting properties, extensive research round the globe has been carried out on carbon nanotubes and carbon nanotubes based systems to investigate their practical usefulness in biomedical applications. The results from these studies demonstrate a great promise in their use in targeted drug delivery systems, diagnostic techniques and in bio-analytical applications. Although, carbon nanotubes possess quite interesting properties, which make them potential candidates in the biomedical science, but they also have some inherent properties which arise great concern regarding their biosafety. In this comprehensive review, we have discussed different aspects of carbon nanotubes and carbon nanotube based systems related to biomedical applications. In the beginning, a short historical account of these tiny yet powerful particles is given followed by discussion regarding their types, properties, methods of synthesis, large scale production method, purification techniques and characterization aspects of carbon nanotubes. In the second part of the review, the functionalization of carbon nanotubes is reviewed in detail, which is not only important to make them biocompatible and stable in biological systems but also render them a great property of loading various biomolecules, diagnostic and therapeutic moieties resulting in diversified applications. In the final part of the review, emphasis is given on the pharmacokinetic aspects of carbon nanotubes including administration routes, absorption mechanisms, distribution and elimination of carbon nanotubes based systems. Lastly, a comprehensive account about the potential biomedical applications has been given followed by insights into the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Conducting polymers: Synthesis and industrial applications

    Energy Technology Data Exchange (ETDEWEB)

    Gottesfeld, S. [Los Alamos National Laboratory, NM (United States)

    1995-05-01

    The Conducting Polymer project funded by the AIM Materials Program is developing new methods for the synthesis of electronically conducting polymers and is evaluating new industrial applications for these materials which will result in significant reductions in energy usage or industrial waste. The applications specifically addressed during FY 1994 are electrochemical capacitors and membranes for gas separation. As an active material in electrochemical capacitors, conducting polymers have the potential of storing large amounts of electrical energy in low cost materials. Such devices are needed in electronics for power failure back-up and peak power, in power supplies for filtering, and in electric vehicles for peak power and load leveling. As a gas electrically adapt the membrane for specific gas combinations. Potential energy savings in the US. for this application are estimated at 1 to 3 quads/yr.

  1. Hollow Micro-/Nanostructures: Synthesis and Applications

    KAUST Repository

    Lou, Xiong Wen (David)

    2008-11-03

    Hollow micro-nanostructures are of great interest in many current and emerging areas of technology. Perhaps the best-known example of the former is the use of fly-ash hollow particles generated from coal power plants as partial replacement for Portland cement, to produce concrete with enhanced strength and durability. This review is devoted to the progress made in the last decade in synthesis and applications of hollow micro-nanostructures. We present a comprehensive overview of synthetic strategies for hollow structures. These strategies are broadly categorized into four themes, which include well-established approaches, such as conventional hard-templating and soft-templating methods, as well as newly emerging methods based on sacrificial templating and template-free synthesis. Success in each has inspired multiple variations that continue to drive the rapid evolution of the field. The Review therefore focuses on the fundamentals of each process, pointing out advantages and disadvantages where appropriate. Strategies for generating more complex hollow structures, such as rattle-type and nonspherical hollow structures, are also discussed. Applications of hollow structures in lithium batteries, catalysis and sensing, and biomedical applications are reviewed. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA,.

  2. Chiral ferrocenes in asymmetric catalysis: synthesis and applications

    National Research Council Canada - National Science Library

    Dai, Li-Xin; Hou, Xue-Long

    2010-01-01

    .... It provides a thorough overview of the synthesis and characterization of different types of chiral ferrocene ligands, their application to various catalytic asymmetric reactions, and versatile chiral...

  3. Synthesis and evaluation of amphiphilic peptides as nanostructures and drug delivery tools

    Science.gov (United States)

    Sayeh, Naser Ali

    the well-known, highly cationic CPPs, such as TAT and Arg9, which do not translocate across phospholipid bilayers, and enter cells mostly by active endocytosis. Alternatively, researchers have found that an effective cellular delivery vector can be improved developed by conjugating a CPP with a fatty acid chain. Amphiphilic peptides have also become a subject of major interest as potent antibacterial agents. Antimicrobial peptides (AMPs) are produced naturally by bacteria and are considered as the first line of host defense protecting living organisms from microorganisms. Various types of AMPs has been discovered, such as defensins, cecropins, magainins and cathelicidins, with significant different structures and bioactivity profiles. The mechanism of actions for these peptides were reported as effectors and regulators of the innate immune system by increasing production and release of chemokine, and enhancing wound healing and angiogenesis. They were able to suppress biofilm formation and induce the dissolution of existing biofilms. Thus, design of new AMPs and more cost effective sequences with highly activity are urgently needed. Although a number of cyclic peptides were discovered and reported as efficient cellular delivery agents or antimicrobial agent, a more systematic investigation is required to identify design rules for optimal entrapment, drug loading, and stability. The balance of many small forces determines the overall morphology, size, and functionality of the structures. A deeper understanding of these factors is required for guiding future research, and for customizing cyclic peptides for drug loading and cellular delivery applications. Thus, additional amphiphilic cyclic and linear peptides were designed with variable electrostatic and hydrophobic residues to optimize drug encapsulation. The diversity in ring size, amino acid number, position and sequences, number of rings, net charge, and hydrophobicity of side chains in cyclic peptides will allow

  4. Synthesis, functionalization, and applications of metal-organic frameworks in biomedicine.

    Science.gov (United States)

    Chen, Wei; Wu, Chunsheng

    2018-02-13

    Metal-organic frameworks (MOFs), also known as coordination polymers, have attracted extensive research interest in the past few decades due to their unique physical structures and potentially vast applications. In this review, we outline the recent progress in the synthesis, functionalization and applications of MOFs in biomedicine, mainly focusing on two promising, yet challenging areas, i.e., drug delivery and biosensing applications. A major challenge is the proper functionalization of MOFs with demanding properties suitable for biomedical applications. Extensive studies on MOFs in biomedicine have led to substantial progress in the control of key properties of MOFs such as toxicity, size and shape, and biological stability. Due to their flexible composition, pore size and easy functionalization properties, MOFs can be utilized as key components for the development of various functional systems, and their applications in drug delivery and biosensing are reviewed. Future trends and perspectives in these research areas are also outlined.

  5. Recent Applications of Polymer Supported Organometallic Catalysts in Organic Synthesis

    Directory of Open Access Journals (Sweden)

    Nina Kann

    2010-09-01

    Full Text Available Recent developments concerning the application of polymer supported organometallic reagents in solid phase synthesis are reviewed, with a special focus on methodology for carbon-carbon formation. Examples of reactions that are covered include the classical Suzuki, Sonogashira and Heck coupings, but also aryl amination, epoxide opening, rearrangements, metathesis and cyclopropanation. Applications in the field of asymmetric synthesis are also discussed.

  6. Nanoparticle-Based Delivery System for Biomedical Applications of RNAi

    DEFF Research Database (Denmark)

    Yang, Chuanxu

    RNA interference (RNAi) is a post-transcriptional gene silencing process triggered by double-strand RNA, including synthetic short interfering RNA (siRNA) and endogenous microRNA (miRNA). RNAi has attracted great attention for developing a new class of therapeutics, due to its capability to speci......RNA/miRNA and transport them to the action site in the target cells. This thesis describes the development of various nanocarriers for siRNA/miRNA delivery and investigate their potential biomedical applications including: anti-inflammation, tissue engineering and cancer...

  7. Electrospinning of polymeric nanofibers for drug delivery applications.

    Science.gov (United States)

    Hu, Xiuli; Liu, Shi; Zhou, Guangyuan; Huang, Yubin; Xie, Zhigang; Jing, Xiabin

    2014-07-10

    Electrospinning has been recognized as a simple and versatile method for fabrication of polymer nanofibers. Various polymers that include synthetic, natural, and hybrid materials have been successfully electrospun into ultrafine fibers. The inherently high surface to volume ratio of electrospun fibers can enhance cell attachment, drug loading, and mass transfer properties. Drugs ranging from antibiotics and anticancer agents to proteins, DNA, RNA, living cells, and various growth factors have been incorporated into electrospun fibers. This article presents an overview of electrospinning techniques and their application in drug delivery. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Monofunctional gold nanoparticles: synthesis and applications

    International Nuclear Information System (INIS)

    Huo Qun; Worden, James G.

    2007-01-01

    The ability to control the assembly of nanoparticle building blocks is critically important for the development of new materials and devices. The properties and functions of nanomaterials are not only dependent on the size and properties of individual particles, but also the interparticle distance and interactions. In order to control the structures of nanoassemblies, it is important to first achieve a precise control on the chemical functionality of nanoparticle building blocks. This review discusses three methods that have been reported recently for the preparation of monofunctional gold nanoparticles, i.e., nanoparticles with a single chemical functional group attached to each particle. The advantages and disadvantages of the three methods are discussed and compared. With a single functional group attached to the surface, one can treat such nanoparticles as molecular building blocks to react with other molecules or nanoparticles. In other words, by using appropriate chemical reactions, nanoparticles can be linked together into nanoassemblies and materials by covalent bonds, similar to the total chemical synthesis of complicated organic compounds from smaller molecular units. An example of using this approach for the synthesis of nanoparticle/polymer hybrid materials with optical limiting properties is presented. Other potential applications and advantages of covalent bond-based nanoarchitectures vs. non-covalent interaction-based supramolecular self-assemblies are also discussed briefly in this review

  9. Synthesis and applications of 13C glycerol

    International Nuclear Information System (INIS)

    Stocking, E.; Khalsa, O.; Martinez, R.A.; Silks, L.A. III

    1994-01-01

    Due in part to the use of labeled glycerol for the 13 C enrichment of biomolecules, we are currently developing new synthetic routes to various isotopomers of glycerol. Judging from our experience, traditional methods of glycerol synthesis are not easily adapted for isotopic enrichment and/or have poor overall yields (12 to 15%). Furthermore, the use of glycerol for enrichment can be prohibitively expensive and its availability is limited by the level of demand. We are presently developing a short de novo synthesis of glycerol from carbon dioxide (∼53% overall yield for four steps) and are examining the feasibility of synthesizing site-specific 13 C-labeled glycerol and dihydroxyacetone (DHA) from labeled methanol and carbon dioxide. One application of 13 C glycerol we have examined is enzymatic conversion of glycerol to glyceraldehyde-3-monophosphate or dihydroxyacetone monophosphate (DHAP) with yields ranging from 25 to 50% (as determined by NMR spectroscopy). We are also pursuing the chemical conversion of 13 C-labeled DHA to DHAP. We are especially interested in 13 C-labeled DHAP because we are investigating its use as a chemo-enzymatic precursor for both labeled 2-deoxyribose and 2-deoxyribonucleic acids

  10. Development of Novel Polymeric Materials for Gene Therapy and pH-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Brian Curtis [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    The underlying theme of this thesis is the use of polymeric materials in bioapplications. Chapters 2-5 either develop a fundamental understanding of current materials used for bioapplications or establish protocols and procedures used in characterizing and synthesizing novel materials. In chapters 6 and 7 these principles and procedures are applied to the development of materials to be used for gene therapy and drug delivery. Chapter one is an introduction to the ideas that will be necessary to understand the subsequent chapters, as well as a literature review of these topics. Chapter two is a paper that has been published in the ''Journal of Controlled Release'' that examines the mechanism of drug release from a polymer gel, as well as experimental design suggestions for the evaluation of water soluble drug delivery systems. Chapter three is a paper that has been published in the ''Journal of Pharmaceutical Sciences'' that discusses the effect ionic salts have on properties of the polymer systems examined in chapter two. Chapter four is a paper published in the Materials Research Society Fall 2000 Symposium Series dealing with the design and synthesis of a pH-sensitive polymeric drug delivery device. Chapter five is a paper that has been published in the journal ''Biomaterials'' proposing a novel polymer/metal composite for use as a biomaterial in hip arthroplasty surgery. Chapter six is a paper that will appear in an upcoming volume of the Journal ''Biomaterials'' dealing with the synthesis of a novel water soluble cationic polymer with possible applications in non-viral gene therapy. Chapter seven is a paper that has been submitted to ''Macromolecules'' discussing several novel block copolymers based on poly(ethylene glycol) and poly(diethylamino ethyl methacrylate) that possess both pH-sensitive and temperature sensitive properties. Chapter eight contains a

  11. Nanostructured metal foams: synthesis and applications

    Energy Technology Data Exchange (ETDEWEB)

    Luther, Erik P [Los Alamos National Laboratory; Tappan, Bryce [Los Alamos National Laboratory; Mueller, Alex [Los Alamos National Laboratory; Mihaila, Bogdan [Los Alamos National Laboratory; Volz, Heather [Los Alamos National Laboratory; Cardenas, Andreas [Los Alamos National Laboratory; Papin, Pallas [Los Alamos National Laboratory; Veauthier, Jackie [Los Alamos National Laboratory; Stan, Marius [Los Alamos National Laboratory

    2009-01-01

    Fabrication of monolithic metallic nanoporous materials is difficult using conventional methodology. Here they report a relatively simple method of synthesizing monolithic, ultralow density, nanostructured metal foams utilizing self-propagating combustion synthesis of novel metal complexes containing high nitrogen energetic ligands. Nanostructured metal foams are formed in a post flame-front dynamic assembly with densities as low as 0.011 g/cc and surface areas as high as 270 m{sup 2}/g. They have produced metal foams via this method of titanium, iron, cobalt, nickel, zirconium, copper, palladium, silver, hafnium, platinum and gold. Microstructural features vary as a function of composition and process parameters. Applications for the metal foams are discussed including hydrogen absorption in palladium foams. A model for the sorption kinetics of hydrogen in the foams is presented.

  12. Synthesis and Applications of Semiconducting Graphene

    Directory of Open Access Journals (Sweden)

    Shahrima Maharubin

    2016-01-01

    Full Text Available Semimetal-to-semiconductor transition in graphene can bestow graphene with numerous novel and enhanced structural, electrical, optical, and physicochemical characteristics. The scope of graphene and its prospective for an array of implications could be significantly outspread by this transition. In consideration of the recent advancements of semiconducting graphene, this article widely reviews the properties, production, and developing operations of this emergent material. The comparisons among the benefits and difficulties of current methods are made, intending to offer evidences to develop novel and scalable synthesis approaches. The emphasis is on the properties and applications resulting from various conversion methods (doping, controlled reduction, and functionalization, expecting to get improved knowledge on semiconducting graphene materials. Intending to motivate further efficient implications, the mechanisms leading to their beneficial usages for energy conversion and storage are also emphasized.

  13. Optical nanoparticles: synthesis and biomedical application

    International Nuclear Information System (INIS)

    Nhung Tran, Hong; Lien Nghiem, Thi Ha; Duong Vu, Thi Thuy; Ha Chu, Viet; Hoa Do, Quang; Vu, Duong; Nghia Nguyen, Trong; Tan Pham, Minh; Son Vu, Van; Nguyen, Thi Thuy; Ngoc Nguyen, Thi Bich; Duc Tran, Anh; Trinh, Thi Thuong; Huan Le, Quang; Thuan Tong, Kim; Thuy Tran, Thanh; Hoang, Thi My Nhung; Thanh Nguyen, Lai; Nguyen Duong, Cao; Minh Pham, Duc

    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 (SiO_2/Au, Fe_3O_4/SiO_2, Fe_3O_4/SiO_2/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 (SiO_2/Au and Fe_3O_4/SiO_2/Au) on cells and tissues were investigated. The nano silver substrates were developed for surface enhanced Raman scattering (SERS) spectroscopy to detect melamine. (review)

  14. Polylactic acid (PLA) controlled delivery carriers for biomedical applications.

    Science.gov (United States)

    Tyler, Betty; Gullotti, David; Mangraviti, Antonella; Utsuki, Tadanobu; Brem, Henry

    2016-12-15

    Polylactic acid (PLA) and its copolymers have a long history of safety in humans and an extensive range of applications. PLA is biocompatible, biodegradable by hydrolysis and enzymatic activity, has a large range of mechanical and physical properties that can be engineered appropriately to suit multiple applications, and has low immunogenicity. Formulations containing PLA have also been Food and Drug Administration (FDA)-approved for multiple applications making PLA suitable for expedited clinical translatability. These biomaterials can be fashioned into sutures, scaffolds, cell carriers, drug delivery systems, and a myriad of fabrications. PLA has been the focus of a multitude of preclinical and clinical testing. Three-dimensional printing has expanded the possibilities of biomedical engineering and has enabled the fabrication of a myriad of platforms for an extensive variety of applications. PLA has been widely used as temporary extracellular matrices in tissue engineering. At the other end of the spectrum, PLA's application as drug-loaded nanoparticle drug carriers, such as liposomes, polymeric nanoparticles, dendrimers, and micelles, can encapsulate otherwise toxic hydrophobic anti-tumor drugs and evade systemic toxicities. The clinical translation of these technologies from preclinical experimental settings is an ever-evolving field with incremental advancements. In this review, some of the biomedical applications of PLA and its copolymers are highlighted and briefly summarized. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Protein cages and synthetic polymers: a fruitful symbiosis for drug delivery applications, bionanotechnology and materials science.

    Science.gov (United States)

    Rother, Martin; Nussbaumer, Martin G; Renggli, Kasper; Bruns, Nico

    2016-11-07

    Protein cages are hollow protein nanoparticles, such as viral capsids, virus-like particles, ferritin, heat-shock proteins and chaperonins. They have well-defined capsule-like structures with a monodisperse size. Their protein subunits can be modified by genetic engineering at predetermined positions, allowing for example site-selective introduction of attachment points for functional groups, catalysts or targeting ligands on their outer surface, in their interior and between subunits. Therefore, protein cages have been extensively explored as functional entities in bionanotechnology, as drug-delivery or gene-delivery vehicles, as nanoreactors or as templates for the synthesis of organic and inorganic nanomaterials. The scope of functionalities and applications of protein cages can be significantly broadened if they are combined with synthetic polymers on their surface or within their interior. For example, PEGylation reduces the immunogenicity of protein cage-based delivery systems and active targeting ligands can be attached via polymer chains to favour their accumulation in diseased tissue. Polymers within protein cages offer the possibility of increasing the loading density of drug molecules, nucleic acids, magnetic resonance imaging contrast agents or catalysts. Moreover, the interaction of protein cages and polymers can be used to modulate the size and shape of some viral capsids to generate structures that do not occur with native viruses. Another possibility is to use the interior of polymer cages as a confined reaction space for polymerization reactions such as atom transfer radical polymerization or rhodium-catalysed polymerization of phenylacetylene. The protein nanoreactors facilitate a higher degree of control over polymer synthesis. This review will summarize the hybrid structures that have been synthesized by polymerizing from protein cage-bound initiators, by conjugating polymers to protein cages, by embedding protein cages into bulk polymeric

  16. Manufacture and Drug Delivery Applications of Silk Nanoparticles.

    Science.gov (United States)

    Wongpinyochit, Thidarat; Johnston, Blair F; Seib, F Philipp

    2016-10-08

    Silk is a promising biopolymer for biomedical and pharmaceutical applications due to its outstanding mechanical properties, biocompatibility and biodegradability, as well its ability to protect and subsequently release its payload in response to a trigger. While silk can be formulated into various material formats, silk nanoparticles are emerging as promising drug delivery systems. Therefore, this article covers the procedures for reverse engineering silk cocoons to yield a regenerated silk solution that can be used to generate stable silk nanoparticles. These nanoparticles are subsequently characterized, drug loaded and explored as a potential anticancer drug delivery system. Briefly, silk cocoons are reverse engineered first by degumming the cocoons, followed by silk dissolution and clean up, to yield an aqueous silk solution. Next, the regenerated silk solution is subjected to nanoprecipitation to yield silk nanoparticles - a simple but powerful method that generates uniform nanoparticles. The silk nanoparticles are characterized according to their size, zeta potential, morphology and stability in aqueous media, as well as their ability to entrap a chemotherapeutic payload and kill human breast cancer cells. Overall, the described methodology yields uniform silk nanoparticles that can be readily explored for a myriad of applications, including their use as a potential nanomedicine.

  17. Nano-Star-Shaped Polymers for Drug Delivery Applications.

    Science.gov (United States)

    Yang, Da-Peng; Oo, Ma Nwe Nwe Linn; Deen, Gulam Roshan; Li, Zibiao; Loh, Xian Jun

    2017-11-01

    With the advancement of polymer engineering, complex star-shaped polymer architectures can be synthesized with ease, bringing about a host of unique properties and applications. The polymer arms can be functionalized with different chemical groups to fine-tune the response behavior or be endowed with targeting ligands or stimuli responsive moieties to control its physicochemical behavior and self-organization in solution. Rheological properties of these solutions can be modulated, which also facilitates the control of the diffusion of the drug from these star-based nanocarriers. However, these star-shaped polymers designed for drug delivery are still in a very early stage of development. Due to the sheer diversity of macromolecules that can take on the star architectures and the various combinations of functional groups that can be cross-linked together, there remain many structure-property relationships which have yet to be fully established. This review aims to provide an introductory perspective on the basic synthetic methods of star-shaped polymers, the properties which can be controlled by the unique architecture, and also recent advances in drug delivery applications related to these star candidates. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Quantum dots in imaging, drug delivery and sensor applications.

    Science.gov (United States)

    Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Pop, Teodora; Mosteanu, Ofelia; Puia, Cosmin; Iancu, Cornel; Mocan, Lucian

    2017-01-01

    Quantum dots (QDs), also known as nanoscale semiconductor crystals, are nanoparticles with unique optical and electronic properties such as bright and intensive fluorescence. Since most conventional organic label dyes do not offer the near-infrared (>650 nm) emission possibility, QDs, with their tunable optical properties, have gained a lot of interest. They possess characteristics such as good chemical and photo-stability, high quantum yield and size-tunable light emission. Different types of QDs can be excited with the same light wavelength, and their narrow emission bands can be detected simultaneously for multiple assays. There is an increasing interest in the development of nano-theranostics platforms for simultaneous sensing, imaging and therapy. QDs have great potential for such applications, with notable results already published in the fields of sensors, drug delivery and biomedical imaging. This review summarizes the latest developments available in literature regarding the use of QDs for medical applications.

  19. Amphiphilic block co-polymers: preparation and application in nanodrug and gene delivery.

    Science.gov (United States)

    Xiong, Xiao-Bing; Binkhathlan, Ziyad; Molavi, Ommoleila; Lavasanifar, Afsaneh

    2012-07-01

    Self-assembly of amphiphilic block co-polymers composed of poly(ethylene oxide) (PEO) as the hydrophilic block and poly(ether)s, poly(amino acid)s, poly(ester)s and polypropyleneoxide (PPO) as the hydrophobic block can lead to the formation of nanoscopic structures of different morphologies. These structures have been the subject of extensive research in the past decade as artificial mimics of lipoproteins and viral vectors for drug and gene delivery. The aim of this review is to provide an overview of the synthesis of commonly used amphiphilic block co-polymers. It will also briefly go over some pharmaceutical applications of amphiphilic block co-polymers as "nanodelivery systems" for small molecules and gene therapeutics. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. Synthesis, characterization, and cytocompatibility of potential cockle shell aragonite nanocrystals for osteoporosis therapy and hormonal delivery

    Directory of Open Access Journals (Sweden)

    Jaji AZ

    2017-01-01

    Full Text Available Alhaji Zubair Jaji,1,2 Md Zuki Bin Abu Bakar,1,3 Rozi Mahmud,4 Mohamad Yusof Loqman,5 Mohamad Noor Mohamad Hezmee,1 Tijani Isa,3 Fu Wenliang,3 Nahidah Ibrahim Hammadi1 1Department of Veterinary Pre-Clinical Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 2Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ilorin, Ilorin, Kwara, Nigeria; 3Molecular Biomedicine Laboratory, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 4Department of Imaging, Faculty of Medicine and Health Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 5Department of Companion Animal Medicine and Surgery, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Calcium carbonate is a porous inorganic nanomaterial with huge potential in biomedical applications and controlled drug delivery. This study aimed at evaluating the physicochemical properties and in vitro efficacy and safety of cockle shell aragonite calcium carbonate nanocrystals (ANC as a potential therapeutic and hormonal delivery vehicle for osteoporosis management. Free and human recombinant parathyroid hormone 1-34 (PTH 1-34-loaded cockle shell aragonite calcium carbonate nanocrystals (PTH-ANC were synthesized and evaluated using standard procedures. Transmission electron microscopy and field emission scanning electron microscopy results demonstrated highly homogenized spherical-shaped aragonite nanocrystals of 30±5 nm diameter. PTH-ANC had a zeta potential of −27.6 ± 8.9 mV. The encapsulation efficiency of the formulation was found to be directly proportional to the concentrations of the drug fed. The X-ray diffraction patterns revealed strong crystallizations with no positional change of peaks before and after PTH-ANC synthesis. Fourier transform infrared spectroscopy demonstrated no detectable interactions between micron-sized aragonite and surfactant at molecular level. PTH-ANC formulation was stabilized

  1. Block Copolymers: Synthesis and Applications in Nanotechnology

    Science.gov (United States)

    Lou, Qin

    This study is focused on the synthesis and study of (block) copolymers using reversible deactivation radical polymerizations (RDRPs), including atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. In particular, two primary areas of study are undertaken: (1) a proof-of-concept application of lithographic block copolymers, and (2) the mechanistic study of the deposition of titania into block copolymer templates for the production of well-ordered titania nanostructures. Block copolymers have the ability to undergo microphase separation, with an average size of each microphase ranging from tens to hundreds of nanometers. As such, block copolymers have been widely considered for nanotechnological applications over the past two decades. The development of materials for various nanotechnologies has become an increasingly studied area as improvements in many applications, such as those found in the semiconductor and photovoltaic industries are constantly being sought. Significant growth in developments of new synthetic methods ( i.e. RDRPs) has allowed the production of block copolymers with molecular (and sometimes atomic) definition. In turn, this has greatly expanded the use of block copolymers in nanotechnology. Herein, we describe the synthesis of statistical and block copolymers of 193 nm photolithography methacrylate and acrylate resist monomers with norbornyl and adamantyl moieties using RAFT polymerization.. For these resist (block) copolymers, the phase separation behaviors were examined by atomic force microscopy (AFM). End groups were removed from the polymers to avoid complications during the photolithography since RAFT end groups absorb visible light. Poly(glycidyl methacrylate-block-polystyrene) (PGMA-b-PS) was synthesize by ATRP and demonstrated that this block copolymer acts as both a lithographic UV (365 nm) photoresist and a self-assembly material. The PGMA segments can undergo cationic

  2. Potential applications for halloysite nanotubes based drug delivery systems

    Science.gov (United States)

    Sun, Lin

    could be released in a sustained manner; (2) cytotoxicity test confirmed the biocompatibility of HNTs and methotrexate coated HNTs; (3) proliferation test confirmed the growth inhibition of released methotrexate on osteosarcoma cells; and (4) nylon-6 could prolong the sustained release of methotrexate from polyelectrolytes coated HNTs. Another application comes from the prevention of surgical site infection. It is a common complication in surgery, which may prolong hospital stay, increase mortality rate, and cause additional financial burden for patients. By directly releasing antibiotics at the surgical site, it is supposed to enhance the drug efficacy and improve the treatment outcome. Therefore, the same HNTs based system was tested with E. coli in vitro to show the potential of delivering antibiotics to enhance the prevention of surgical site infection. Nitrofurantoin was incorporated within HNTs using the layer-by-layer coating technique, and the drug coated HNTs were filled into nylon-6 again. Results showed that (1) nitrofurantoin could be incorporated with this HNTs based drug delivery system, and released in a sustained manner; (2) nylon-6 could prolong the sustained release of nitrofurantoin from polyelectrolytes coated HNTs; and (3) released nitrofurantoin could severely inhibit E. coil growth. Therefore, a tunable drug delivery system based on HNTs was developed, and a great potential of medical application in drug delivery was shown.

  3. Nanoparticles as conjugated delivery agents for therapeutic applications

    Science.gov (United States)

    Muroski, Megan Elizabeth

    a molecular beacon. The development of non-viral transfection approaches using gold nanoparticles (AuNP) as a gene carrier allows the implementation of advanced biophysical tools to follow the transfection cycle by utilizing nanometal surface energy transfer (NSET) molecular beacon methods coupled to delivery of a gene that induces a fluorescent protein. The change in photoluminescence of an appended dye following gene release from the AuNP surface within endosomes can be tempo-rally and spatially followed. The ability to correlate the release events with the protein expression event by simultaneously monitoring fluorescent protein production provides insight into package uptake, nanoparticle disassembly, and final gene expression. Employing AuNP transfection constructs and then monitoring the stages of the transfection cycle via NSET, indicates delivery of the constructs leads to gene release from the AuNP surface within the endosome followed by slow cytosolic diffusion. The slow diffusion is the limiting step for transfection and impacts the protein yield due to competing degradation processes. Chapter 4 aims to improve the NP conjugate through the use of cell penetrating peptides (CPP) to Transfect Primary Cells. All future clinical applications of mesenchymal stem cell (MSC) therapies must allow the MSC to be harvested, transfected, and induced to express a desired protein or selection of proteins to have medical benefit. For the full potential of MSC cell therapy to be realized, it is desirable to be able to systematically alter the protein expression in harvested MSC cells with high fidelity in a single transfection event. We have developed a bimodal delivery platform based on the use of a solid gold core nanoparticle that has been surface modified to produce a chimera containing a protein transduction domain (PTD) sequence to enhance cellular uptake and a linearized expression vector to induce protein production. The transfection chimera is observed to be an

  4. Theory and in vivo application of electroporative gene delivery.

    Science.gov (United States)

    Somiari, S; Glasspool-Malone, J; Drabick, J J; Gilbert, R A; Heller, R; Jaroszeski, M J; Malone, R W

    2000-09-01

    Efficient and safe methods for delivering exogenous genetic material into tissues must be developed before the clinical potential of gene therapy will be realized. Recently, in vivo electroporation has emerged as a leading technology for developing nonviral gene therapies and nucleic acid vaccines (NAV). Electroporation (EP) involves the application of pulsed electric fields to cells to enhance cell permeability, resulting in exogenous polynucleotide transit across the cytoplasmic membrane. Similar pulsed electrical field treatments are employed in a wide range of biotechnological processes including in vitro EP, hybridoma production, development of transgenic animals, and clinical electrochemotherapy. Electroporative gene delivery studies benefit from well-developed literature that may be used to guide experimental design and interpretation. Both theory and experimental analysis predict that the critical parameters governing EP efficacy include cell size and field strength, duration, frequency, and total number of applied pulses. These parameters must be optimized for each tissue in order to maximize gene delivery while minimizing irreversible cell damage. By providing an overview of the theory and practice of electroporative gene transfer, this review intends to aid researchers that wish to employ the method for preclinical and translational gene therapy, NAV, and functional genomic research.

  5. Synthesis and properties of unagglomerated nanocomposite particles for nanomedical applications

    Science.gov (United States)

    Rouse, Sarah M.

    2005-11-01

    Methods have been developed to prepare stable, unagglomerated active-medical-agent nanoparticles in a range of sizes, based on reverse-micelle microemulsion techniques. The process used to prepare monodisperse, spherical nanocomposite particles is based on methods originally outlined in detail by Adair et al. and Li et al. The "Molecular Dot" (MD) nanoparticles incorporate a variety of medically-active substances, such as organic fluorophores and therapeutic drugs, internally distributed in silica, titania, calcium phosphate, or calcium phospho-silicate matrices. The synthesis techniques have also been modified to produce nanoparticles containing combinations of fluorophores and medicinal agents, in order to monitor drug release and location. The specific biomedical application for the nanocomposite particles dictates the selection of core and shell-matrix materials. For example, the protective shell-matrices of the silica and titania MDs shield the active-medical agents from damage due to changes in pH, temperature, and other environmental effects. Conversely, the calcium phosphate and calcium phospho-silicate shell-matrix nanoparticles can potentially be engineered to dissolve in physiological environments. The method used to remove residual precursor materials while maintaining a well-dispersed assembly of nanoparticles is critical to the use of nanocolloids in medical applications. The dispersion approach is based on protection-dispersion theory tailored to accommodate the high surface areas and reactivity of sub-50 nm particles in aqueous or water/ethanol mixtures. Dispersion of the nanocomposite particles is further enhanced with the use of size-exclusion high performance liquid chromatography (HPLC) to simultaneously wash and disperse the nanocomposite particle suspensions. The state of dispersion of the nanosuspensions is evaluated using the average agglomeration number (AAN) approach in conjunction with other characterization techniques. The formulation of

  6. Ferromagnetic filled carbon nanotubes and nanoparticles: synthesis and lipid-mediated delivery into human tumor cells

    International Nuclear Information System (INIS)

    Moench, I.; Meye, A.; Leonhardt, A.; Kraemer, K.; Kozhuharova, R.; Gemming, T.; Wirth, M.P.; Buechner, B.

    2005-01-01

    We describe the synthesis and the properties of Fe-filled multi-walled carbon nanotubes (MWNTs) and nanoparticles (NP) produced by chemical vapor deposition (CVD). We have employed ferrocene as a starting substance and oxidized Si-wafers as substrates. The magnetic properties and the interaction of the material with bladder cancer cells were determined. After the addition of NP suspensions to cultured cells, no adhesion of the nanoparticles/nanotubes (NT/NP) to the cell membrane and also no cellular uptake were observed. However, the preincubation of the (NT/NP) suspension with cationic lipid caused an efficient delivery of the lipid-nanostructure complexes into the cytoplasm within 2 h after adding to the culture medium

  7. Synthesis, characterization and applications of graphene architectures

    Science.gov (United States)

    Thomas, Abhay Varghese

    Graphene, a two--dimensional sheet of sp2 hybridized carbon atoms arranged in a honeycomb lattice structure, has garnered tremendous interest from the scientific community for its unique combination of properties. It has interesting electrical, thermal, optical and mechanical properties that scientists and engineers are trying to understand and harness to improve current products as well as focus on disruptive technologies that can be made possible by this next generation material. In this thesis the synthesis, characterization and applications of various graphene architectures were explored from the context of a bottom--up and top--down synthesis approach. The work is divided into three main chapters and each one deals with a unique architecture of graphene as well as its properties and an application to a real world problem. In Chapter 2, we focus on bottom--up synthesis of graphene sheets by chemical vapor deposition. We then studied the wetting properties of graphene coated surfaces. More specifically the wetting properties of single and multilayer graphene films on flat and nanoscale rough surfaces are explored and the insights gained are used in improving heat transfer performance of copper surfaces. Single layer graphene, on certain flat surfaces, was shown to exhibit `wetting transparency' as a result of its sheer thinness and this property is of interest in various wetting related applications. Surface protection from corrosion and/or oxidation without change in wetting properties is tremendously useful in multiple fields and we looked to apply this property to dehumidification of copper surfaces. The short time scales results demonstrated that graphene indeed served to prevent oxidation of the surface which in turn promoted increased heat transfer co--efficients with respect to the oxidized copper surfaces. Closer inspection of the surface over long time scales however revealed that the oxide layer changed the wetting properties and this was detrimental

  8. Synthesis of Nano Hydroxyapatite: Application in Drug Delivery of Sulfasalazine

    Directory of Open Access Journals (Sweden)

    D. Moslemi

    2015-10-01

    Full Text Available In this work we synthesized Nano hydroxyapatite (HAp  by Sol-gel method, Then we functionalized hydroxyapatite nanoparticle by use of  3-Aminopropyl trimethoxysilane (APTMS , to improve the loading and control release of sulfasalazine drug bonded to APTMS. The drug release patterns from Sulfasalazine loaded HAp nanoparticles at pH value 8 For 6h, Sulfasalazine loaded functionalized HAp nanoparticles (Sulfasalazine loaded HAp-APTMS at pH value 8 as in the intestine for 48h. Moreover, the functionalized HAp showed relatively slower release rate of sulfasalazine compare with non functionalized HAp. because the strong ionic interaction between NH2 group in sulfasalazine in HAp-APTMS. On other side, the functionalized HAp loaded more drug than pure HAp. The synthesized nanoparticles and functionalized HAp characterized by Scanning Electron Microscopy (SEM, X-ray Diffraction (XRD, Fourier transform infrared (FT-IR and  UV/Vis analysis techniques. Then the obtained material was studied in the simulated body fluid (SBF to this investigated storage and release properties.

  9. Sonochemically synthesized biocompatible zirconium phosphate nanoparticles for pH sensitive drug delivery application.

    Science.gov (United States)

    Kalita, Himani; Prashanth Kumar, B N; Konar, Suraj; Tantubay, Sangeeta; Kr Mahto, Madhusudan; Mandal, Mahitosh; Pathak, Amita

    2016-03-01

    The present work reports the synthesis of biocompatible zirconium phosphate (ZP) nanoparticles as nanocarrier for drug delivery application. The ZP nanoparticles were synthesized via a simple sonochemical method in the presence of cetyltrimethylammonium bromide and their efficacy for the delivery of drugs has been tested through various in-vitro experiments. The particle size and BET surface area of the nanoparticles were found to be ~48 nm and 206.51 m(2)/g respectively. The conventional MTT assay and cellular localization studies of the particles, performed on MDA-MB-231 cell lines, demonstrate their excellent biocompatibility and cellular internalization behavior. The loading of curcumin, an antitumor drug, onto the ZP nanoparticles shows the rapid drug uptake ability of the particles, while the drug release study, performed at two different pH values (at 7.4 and 5) depicts pH sensitive release-profile. The MTT assay and cellular localization studies revealed higher cellular inhibition and better bioavailability of the nanoformulated curcumin compared to free curcumin. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Solid lipid nanoparticles as oral delivery systems of phenolic compounds: Overcoming pharmacokinetic limitations for nutraceutical applications.

    Science.gov (United States)

    Nunes, Sara; Madureira, Ana Raquel; Campos, Débora; Sarmento, Bruno; Gomes, Ana Maria; Pintado, Manuela; Reis, Flávio

    2017-06-13

    Drug delivery systems, accompanied by nanoparticle technology, have recently emerged as prominent solutions to improve the pharmacokinetic properties, namely bioavailability, of therapeutic and nutraceutical agents. Solid lipid nanoparticles (SLNs) have received much attention from researchers due to their potential to protect or improve drug properties. SLNs have been reported to be an alternative system to traditional carriers, such as emulsions, liposomes, and polymeric nanoparticles. Phenolic compounds are widespread in plant-derived foodstuffs and therefore abundant in our diet. Over the last decades, phenolic compounds have received considerable attention due to several health promoting properties, mostly related to their antioxidant activity, which can have important implications for health. However, most of these compounds have been associated with poor bioavailability being poorly absorbed, rapidly metabolized and eliminated, which compromises its biological and pharmacological benefits. This paper provides a systematic review of the use of SLNs as oral delivery systems of phenolic compounds, in order to overcome pharmacokinetic limitations of these compounds and improved nutraceutical potential. In vitro studies, as well as works describing topical and oral treatments will be revisited and discussed. The classification, synthesis, and clinical application of these nanomaterials will be also considered in this review article.

  11. Sonochemically synthesized biocompatible zirconium phosphate nanoparticles for pH sensitive drug delivery application

    Energy Technology Data Exchange (ETDEWEB)

    Kalita, Himani, E-mail: hkalita74@gmail.com [Department of Chemistry, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Prashanth Kumar, B.N., E-mail: prasanthkumar999@gmail.com [School of Medical Science and Technology, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Konar, Suraj, E-mail: suraj.konar@gmail.com [Department of Chemistry, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Tantubay, Sangeeta, E-mail: sang.chem2@gmail.com [Department of Chemistry, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Mahto, Madhusudan Kr., E-mail: mahtomk0@gmail.com [Department of Chemistry, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Mandal, Mahitosh, E-mail: mahitosh@smst.iitkgp.ernet.in [School of Medical Science and Technology, Indian Institute of Technology Kharagpur, West Bengal 721302 (India); Pathak, Amita, E-mail: ami@chem.iitkgp.ernet.in [Department of Chemistry, Indian Institute of Technology Kharagpur, West Bengal 721302 (India)

    2016-03-01

    The present work reports the synthesis of biocompatible zirconium phosphate (ZP) nanoparticles as nanocarrier for drug delivery application. The ZP nanoparticles were synthesized via a simple sonochemical method in the presence of cetyltrimethylammonium bromide and their efficacy for the delivery of drugs has been tested through various in-vitro experiments. The particle size and BET surface area of the nanoparticles were found to be ~ 48 nm and 206.51 m{sup 2}/g respectively. The conventional MTT assay and cellular localization studies of the particles, performed on MDA-MB-231 cell lines, demonstrate their excellent biocompatibility and cellular internalization behavior. The loading of curcumin, an antitumor drug, onto the ZP nanoparticles shows the rapid drug uptake ability of the particles, while the drug release study, performed at two different pH values (at 7.4 and 5) depicts pH sensitive release-profile. The MTT assay and cellular localization studies revealed higher cellular inhibition and better bioavailability of the nanoformulated curcumin compared to free curcumin. - Highlights: • Biocompatible zirconium phosphate nanoparticles were synthesized by a simple sonochemical approach. • Curcumin was rapidly loaded onto the particles by the aid by hydrogen bond formation. • The curcumin loaded zirconium phosphate nanoparticles depict pH triggered drug release phenomenon. • The nanoformulated curcumin showed enhanced anti-tumor activity as compared to the native curcumin.

  12. Sonochemically synthesized biocompatible zirconium phosphate nanoparticles for pH sensitive drug delivery application

    International Nuclear Information System (INIS)

    Kalita, Himani; Prashanth Kumar, B.N.; Konar, Suraj; Tantubay, Sangeeta; Mahto, Madhusudan Kr.; Mandal, Mahitosh; Pathak, Amita

    2016-01-01

    The present work reports the synthesis of biocompatible zirconium phosphate (ZP) nanoparticles as nanocarrier for drug delivery application. The ZP nanoparticles were synthesized via a simple sonochemical method in the presence of cetyltrimethylammonium bromide and their efficacy for the delivery of drugs has been tested through various in-vitro experiments. The particle size and BET surface area of the nanoparticles were found to be ~ 48 nm and 206.51 m"2/g respectively. The conventional MTT assay and cellular localization studies of the particles, performed on MDA-MB-231 cell lines, demonstrate their excellent biocompatibility and cellular internalization behavior. The loading of curcumin, an antitumor drug, onto the ZP nanoparticles shows the rapid drug uptake ability of the particles, while the drug release study, performed at two different pH values (at 7.4 and 5) depicts pH sensitive release-profile. The MTT assay and cellular localization studies revealed higher cellular inhibition and better bioavailability of the nanoformulated curcumin compared to free curcumin. - Highlights: • Biocompatible zirconium phosphate nanoparticles were synthesized by a simple sonochemical approach. • Curcumin was rapidly loaded onto the particles by the aid by hydrogen bond formation. • The curcumin loaded zirconium phosphate nanoparticles depict pH triggered drug release phenomenon. • The nanoformulated curcumin showed enhanced anti-tumor activity as compared to the native curcumin.

  13. Ferrite nanoparticles: Synthesis, characterisation and applications in electronic device

    Energy Technology Data Exchange (ETDEWEB)

    Kefeni, Kebede K., E-mail: kkefeni@gmail.com; Msagati, Titus A.M.; Mamba, Bhekie B.

    2017-01-15

    Highlights: • Available synthesis methods of ferrite nanoparticles (FNPs) are briefly reviewed. • Summary of the advantage and limitation of FNPs synthesis techniques are presented. • The existing most common FNPs characterisation techniques are briefly reviewed. • Major application areas of FNPs in electronic materials are reviewed. - Abstract: Ferrite nanoparticles (FNPs) have attracted a great interest due to their wide applications in several areas such as biomedical, wastewater treatment, catalyst and electronic device. This review focuses on the synthesis, characterisation and application of FNPs in electronic device with more emphasis on the recently published works. The most commonly used synthesis techniques along with their advantages and limitations are discussed. The available characterisation techniques and their application in electronic materials such as sensors and biosensors, energy storage, microwave device, electromagnetic interference shielding and high-density recording media are briefly reviewed.

  14. Electrochemically Active Biofilms Assisted Nanomaterial Synthesis for Environmental Applications

    KAUST Repository

    Ahmed, Elaf

    2017-01-01

    Nanomaterials have a great potential for environmental applications due to their high surface areas and high reactivity. This dissertation investigated the use of electrochemically active biofilms (EABs) as a synthesis approach for the fabrication

  15. Gold nanocages: from synthesis to theranostic applications.

    Science.gov (United States)

    Xia, Younan; Li, Weiyang; Cobley, Claire M; Chen, Jingyi; Xia, Xiaohu; Zhang, Qiang; Yang, Miaoxin; Cho, Eun Chul; Brown, Paige K

    2011-10-18

    some of the most recent advances in the use of Au nanocages for a broad range of theranostic applications. First, we describe their use as tracers for tracking by multiphoton luminescence. Gold nanocages can also serve as contrast agents for photoacoustic (PA) and mutimodal (PA/fluorescence) imaging. In addition, these nanostructures can be used as photothermal agents for the selective destruction of cancerous or diseased tissue. Finally, Au nanocages can serve as drug delivery vehicles for controlled and localized release in response to external stimuli such as NIR radiation or high-intensity focused ultrasound (HIFU).

  16. Supramolecular Nanostructures Based on Cyclodextrin and Poly(ethylene oxide: Syntheses, Structural Characterizations and Applications for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Yue Zheng

    2016-05-01

    Full Text Available Cyclodextrins (CDs have been extensively studied as drug delivery carriers through host–guest interactions. CD-based poly(pseudorotaxanes, which are composed of one or more CD rings threading on the polymer chain with or without bulky groups (or stoppers, have attracted great interest in the development of supramolecular biomaterials. Poly(ethylene oxide (PEO is a water-soluble, biocompatible polymer. Depending on the molecular weight, PEO can be used as a plasticizer or as a toughening agent. Moreover, the hydrogels of PEO are also extensively studied because of their outstanding characteristics in biological drug delivery systems. These biomaterials based on CD and PEO for controlled drug delivery have received increasing attention in recent years. In this review, we summarize the recent progress in supramolecular architectures, focusing on poly(pseudorotaxanes, vesicles and supramolecular hydrogels based on CDs and PEO for drug delivery. Particular focus will be devoted to the structures and properties of supramolecular copolymers based on these materials as well as their use for the design and synthesis of supramolecular hydrogels. Moreover, the various applications of drug delivery techniques such as drug absorption, controlled release and drug targeting based CD/PEO supramolecular complexes, are also discussed.

  17. Engineered magnetic core shell nanoprobes: Synthesis and applications to cancer imaging and therapeutics.

    Science.gov (United States)

    Mandal, Samir; Chaudhuri, Keya

    2016-02-26

    Magnetic core shell nanoparticles are composed of a highly magnetic core material surrounded by a thin shell of desired drug, polymer or metal oxide. These magnetic core shell nanoparticles have a wide range of applications in biomedical research, more specifically in tissue imaging, drug delivery and therapeutics. The present review discusses the up-to-date knowledge on the various procedures for synthesis of magnetic core shell nanoparticles along with their applications in cancer imaging, drug delivery and hyperthermia or cancer therapeutics. Literature in this area shows that magnetic core shell nanoparticle-based imaging, drug targeting and therapy through hyperthermia can potentially be a powerful tool for the advanced diagnosis and treatment of various cancers.

  18. Silver nanoparticles: Synthesis methods, bio-applications and properties.

    Science.gov (United States)

    Abbasi, Elham; Milani, Morteza; Fekri Aval, Sedigheh; Kouhi, Mohammad; Akbarzadeh, Abolfazl; Tayefi Nasrabadi, Hamid; Nikasa, Parisa; Joo, San Woo; Hanifehpour, Younes; Nejati-Koshki, Kazem; Samiei, Mohammad

    2016-01-01

    Silver nanoparticles size makes wide range of new applications in various fields of industry. Synthesis of noble metal nanoparticles for applications such as catalysis, electronics, optics, environmental and biotechnology is an area of constant interest. Two main methods for Silver nanoparticles are the physical and chemical methods. The problem with these methods is absorption of toxic substances onto them. Green synthesis approaches overcome this limitation. Silver nanoparticles size makes wide range of new applications in various fields of industry. This article summarizes exclusively scalable techniques and focuses on strengths, respectively, limitations with respect to the biomedical applicability and regulatory requirements concerning silver nanoparticles.

  19. Polymer nanotube nanocomposites: synthesis, properties, and applications

    National Research Council Canada - National Science Library

    Mittal, Vikas

    2010-01-01

    ... in these commercially important areas of polymer technology. It sums up recent advances in nanotube composite synthesis technology, provides basic introduction to polymer nanotubes nanocomposite technology for the readers new to this field, provides valuable...

  20. Synthesis, Characterization and Application of Nano Lepidocrocite ...

    African Journals Online (AJOL)

    NICO

    Degradation of halogenated organic compounds using nanoparticles is one of the innovative ... way as the synthesis of nano zero-valent iron by using sodium .... +. −. 2и High. 2и Low. FWHM. Crystallite. /counts. /counts. /degree. /degree.

  1. Carbon and oxide nanostructures. Synthesis, characterisation and applications

    Energy Technology Data Exchange (ETDEWEB)

    Yahya, Noorhana [Universiti Teknologi PETRONAS, Tronoh, Perak (Malaysia). Dept. of Fundamental and Applied Sciences

    2010-07-01

    This volume covers all aspects of carbon and oxide based nanostructured materials. The topics include synthesis, characterization and application of carbon-based namely carbon nanotubes, carbon nanofibres, fullerenes, carbon filled composites etc. In addition, metal oxides namely, ZnO, TiO2, Fe2O3, ferrites, garnets etc., for various applications like sensors, solar cells, transformers, antennas, catalysts, batteries, lubricants, are presented. The book also includes the modeling of oxide and carbon based nanomaterials. The book covers the topics: - Synthesis, characterization and application of carbon nanotubes, carbon nanofibres, fullerenes - Synthesis, characterization and application of oxide based nanomaterials. - Nanostructured magnetic and electric materials and their applications. - Nanostructured materials for petro-chemical industry. - Oxide and carbon based thin films for electronics and sustainable energy. - Theory, calculations and modeling of nanostructured materials. (orig.)

  2. Microencapsulation of indocyanine green for potential applications in image-guided drug delivery.

    Science.gov (United States)

    Zhu, Zhiqiang; Si, Ting; Xu, Ronald X

    2015-02-07

    We present a novel process to encapsulate indocyanine green (ICG) in liposomal droplets at high concentration for potential applications in image-guided drug delivery. The microencapsulation process follows two consecutive steps of droplet formation by liquid-driven coaxial flow focusing (LDCFF) and solvent removal by oil phase dewetting. These biocompatible lipid vesicles may have important applications in drug delivery and fluorescence imaging.

  3. Synthesis of thiolated chitosan and preparation nanoparticles with sodium alginate for ocular drug delivery.

    Science.gov (United States)

    Zhu, Xuan; Su, Meiqin; Tang, Shaoheng; Wang, Lingsong; Liang, Xinfang; Meng, Feihong; Hong, Ying; Xu, Zhiran

    2012-01-01

    The goal of the present study was to synthesize mucoadhesive polymer - thiolated chitosan (TCS) from chitosan (CS), then prepared CS/TCS-sodium alginate nanoparticles (CS/TCS-SA NPs), determined which was more potential for ocular drug delivery. A new method for preparing TCS was developed, and the characteristics were determined using Fourier transform infrared spectroscopy and the degree of thiol immobilized was measured by Ellman's reagent. Human corneal epithelium (HCE) cells were incubated with different concentrations of TCS for 48 h to determine the cell viabilities. CS/TCS-SA NPs were prepared and optimized by a modified ionic gelation method. The particle sizes, zeta potentials, Scanning electron microscopy images, mucoadhesion, in vitro cell uptake and in vivo studies of the two types of NP were compared. The new method enabled a high degree of thiol substitution of TCS, up to 1,411.01±4.02 μmol/g. In vitro cytocompatibility results suggest that TCS is nontoxic. Compared to CS-SA NPs, TCS-SA NPs were more stable, with higher mucoadhesive properties and could deliver greater amounts of drugs into HCE cells in vitro and cornea in vivo. TCS-SA NPs have better delivery capability, suggesting they have good potential for ocular drug delivery applications.

  4. Synthesis and characterization of thiolated carboxymethyl chitosan-graft-cyclodextrin nanoparticles as a drug delivery vehicle for albendazole.

    Science.gov (United States)

    Alamdarnejad, Ghazaleh; Sharif, Alireza; Taranejoo, Shahrouz; Janmaleki, Mohsen; Kalaee, Mohammad Reza; Dadgar, Mohsen; Khakpour, Mazyar

    2013-08-01

    A new strategy for the synthesis of thiolated carboxymethyl chitosan-g-cyclodextrin nanoparticles by an ionic-gelation method is presented. The synthetic approach was based on the utilization of 1,6-hexamethylene diisocyanate during cyclodextrin grafting onto carboxymethyl chitosan. The use of the 1,6-hexamethylene diisocyanate resulted in reactions between cyclodextrin and active sites at the C6-position of chitosan, and preserved amino groups of chitosan for subsequent reactions with thioglycolic acid, as the thiolating agent, and tripolyphosphate, as the gelling counterion. Various methods such as scanning electron microscopy, rheology and in vitro release studies were employed to exhibit significant features of the nanoparticles for mucosal albendazole delivery applications. It was found that the thiolated carboxymethyl chitosan-g-cyclodextrin nanoparticles prepared using an aqueous solution containing 1 wt% of tripolyphosphate and having 115.65 (μmol/g polymer) of grafted thiol groups show both the highest mucoadhesive properties and the highest albendazole entrapment efficiency. The latter was confirmed theoretically by calculating the enthalpy of mixing of albendazole in the above thiolated chitosan polymer.

  5. Gold nanoparticle trapping and delivery for therapeutic applications

    Directory of Open Access Journals (Sweden)

    Aziz MS

    2011-12-01

    Full Text Available MS Aziz1, Nathaporn Suwanpayak3,4, Muhammad Arif Jalil2, R Jomtarak4, T Saktioto2, Jalil Ali1, PP Yupapin41Institute of Advanced Photonics Science, 2Ibnu Sina Institute of Fundamental Science Studies, Nanotechnology Research Alliance, Universiti Teknologi Malaysia, Johor Bahru, Malaysia; 3King Mongkut's Institute of Technology Ladkrabang, Chump on Campus, Chumphon, 4Nanoscale Science and Engineering Research Alliance (N'SERA, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Bangkok, ThailandAbstract: A new optical trapping design to transport gold nanoparticles using a PANDA ring resonator system is proposed. Intense optical fields in the form of dark solitons controlled by Gaussian pulses are used to trap and transport nanoscopic volumes of matter to the desired destination via an optical waveguide. Theoretically, the gradient and scattering forces are responsible for this trapping phenomenon, where in practice such systems can be fabricated and a thin-film device formed on the specific artificial medical materials, for instance, an artificial bone. The dynamic behavior of the tweezers can be tuned by controlling the optical pulse input power and parameters of the ring resonator system. Different trap sizes can be generated to trap different gold nanoparticles sizes, which is useful for gold nanoparticle therapy. In this paper, we have shown the utility of gold nanoparticle trapping and delivery for therapy, which may be useful for cosmetic therapy and related applications.Keywords: gold nanoparticle trapping, particle trapping, therapy, transport

  6. Chemical functionalization of hyaluronic acid for drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Vasi, Ana-Maria [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); Popa, Marcel Ionel, E-mail: mipopa@ch.tuiasi.ro [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); Butnaru, Maria [“Grigore T. Popa” University of Medicine Pharmacy, Faculty of Medical Bioengineering, 9-13 Kogalniceanu Street, 700454 Iasi (Romania); Dodi, Gianina [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); SCIENT — Research Center for Instrumental Analysis, S.C. CROMATEC PLUS, 18 Sos. Cotroceni, 060114 Bucharest (Romania); Verestiuc, Liliana [“Grigore T. Popa” University of Medicine Pharmacy, Faculty of Medical Bioengineering, 9-13 Kogalniceanu Street, 700454 Iasi (Romania)

    2014-05-01

    Functionalized hyaluronic acid (HA) derivatives were obtained by ring opening mechanism of maleic anhydride (MA). FTIR and H{sup 1} NMR spectroscopy were used to confirm the chemical linkage of MA on the hyaluronic acid chains. Thermal analysis (TG-DTG and DSC) and GPC data for the new products revealed the formation of new functional groups, without significant changes in molecular weight and thermal stability. New gels based on hyaluronic acid modified derivatives were obtained by acrylic acid copolymerization in the presence of a redox initiation system. The resulted circular and interconnected pores of the gels were visualized by SEM. The release profiles of an ophthalmic model drug, pilocarpine from tested gels were studied in simulated media. Evaluation of the cytotoxicity and cell proliferation properties indicates the potential of the new systems to be used in contact with biological media in drug delivery applications. - Highlights: • New functionalized hyaluronic acid was prepared by ring opening of maleic anhydride. • Gels with circular pores based on acrylic acid copolymerization were formulated. • In vitro drug loading/release profile was evaluated in simulated ophthalmic media. • The cytotoxicity indicates the potential of derivatives to be used in vivo.

  7. Application of ion exchange resin in floating drug delivery system.

    Science.gov (United States)

    Upadhye, Abhijeet A; Ambike, Anshuman A; Mahadik, Kakasaheb R; Paradkar, Anant

    2008-10-01

    The purpose of this study was to explore the application of low-density ion exchange resin (IER) Tulsion(R) 344, for floating drug delivery system (FDDS), and study the effect of its particle size on rate of complexation, water uptake, drug release, and in situ complex formation. Batch method was used for the preparation of complexes, which were characterized by physical methods. Tablet containing resin with high degree of crosslinking showed buoyancy lag time (BLT) of 5-8 min. Decreasing the particle size of resin showed decrease in water uptake and drug release, with no significant effect on the rate of complexation and in situ complex formation for both preformed complexes (PCs) and physical mixtures (PMs). Thus, low-density and high degree of crosslinking of resin and water uptake may be the governing factor for controlling the initial release of tablet containing PMs but not in situ complex formation. However, further sustained release may be due to in situ complex formation.

  8. Hydrogels for efficient light delivery in optogenetic applications

    Science.gov (United States)

    Johannsmeier, S.; Torres, M. L.; Ripken, T.; Heinemann, D.; Heisterkamp, A.

    2018-02-01

    Light-based therapies have been established for various indications, such as skin conditions, cancer or neonatal jaundice. Advances in the field of optogenetics open up new horizons for light-tissue interactions with an organism-wide impact. Excitable tissues, such as nerve and muscle tissues, can be controlled by light after the introduction of light-sensitive ion channels. Since these organs are generally not easily accessible to illumination in vivo, there is an increasing need for effective biocompatible waveguides for light delivery. These devices not only have to guide and distribute the light as desired with minimal losses, they should also mimic the mechanical properties of the surrounding tissue to ensure compatibility. In this project, we are tuning the properties of hydrogels from poly(ethylene glycol) derivatives to achieve compatibility with muscle tissue as well as optimal light guiding and distribution for optogenetic applications at the heart. The excitation light is coupled into the hydrogel with a biocompatible fiber. Properties of the hydrogel are mainly tuned by monomer length and concentration. Total reflection can be achieved by embedding a fiber-like hydrogel with a high refractive index into a second, low refractive index gel. Different geometries and scattering microparticles are used for light distribution in a flat gel patch. Targeted cell attachment can be achieved by introducing a protein layer to the otherwise bioinert gel. After optimization, the hydrogel may be used to deliver light for the excitation of genetically altered cardiomyocytes for controlled contraction.

  9. Targeted drug delivery to magnetic implants for therapeutic applications

    International Nuclear Information System (INIS)

    Yellen, Benjamin B.; Forbes, Zachary G.; Halverson, Derek S.; Fridman, Gregory; Barbee, Kenneth A.; Chorny, Michael; Levy, Robert; Friedman, Gary

    2005-01-01

    A new method for locally targeted drug delivery is proposed that employs magnetic implants placed directly in the cardiovascular system to attract injected magnetic carriers. Theoretical simulations and experimental results support the assumption that using magnetic implants in combination with externally applied magnetic field will optimize the delivery of magnetic drug to selected sites within a subject

  10. Image-guided drug delivery: preclinical applications and clinical translation

    NARCIS (Netherlands)

    Ojha, Tarun; Rizzo, Larissa; Storm, Gerrit; Kiessling, Fabian; Lammers, Twan Gerardus Gertudis Maria

    2015-01-01

    Image-guided drug delivery refers to the combination of drug targeting and imaging. Preclinically, image-guided drug delivery can be used for several different purposes, including for monitoring biodistribution, target site accumulation, off-target localization, drug release and drug efficacy.

  11. Synthesis and application of labelled growth regulators

    International Nuclear Information System (INIS)

    Shyutte, G.R.

    1982-01-01

    For the investigation of the metabolism both of phytoeffectors like herbicides and plant growth regulators such compounds are needed in radioactive labelled form. The synthesis of radioactive labelled fluorodifen, nitrofen, ethephon, diphenylic acetic acid, 2,4-dichlorophenoxyisobutyric acid, abscisic acid, hydroxybenzoic acids and different conjugates are described. Some examples of these compounds metabolism in plants are discussed [ru

  12. Hybrid principle with applications to synthesis

    International Nuclear Information System (INIS)

    Nanneh, M.M.

    1991-01-01

    The theory of hybrid principles is presented together with the transformation rule for converting odd-parity approximations into even-parity approximations. This rule leads to a method which provides rigorous upper and lower bounds for the disadvantage factor for a reactor lattice cell. With these bounds very precise benchmarks have been constructed for representative lattices. It is found that a combination of even and odd-parity solutions for the neutron flux is much more efficient than solutions based on either the even-parity or odd-parity. This is the basis of one synthesis scheme. In another synthesis method, a hybrid principle with trial functions for both the even- and odd- parity angular flux is used in conjunction with a classical principle with an odd-parity trial function. The synthesis process is efficient because the largest set of equations to be solved, i.e. the frame work, involves as few as one unknown per node of the finite element mesh. The effectiveness of the synthesis method is demonstrated for a thick shield problem. (author)

  13. Advances in the Applications of Polyhydroxyalkanoate Nanoparticles for Novel Drug Delivery System

    Directory of Open Access Journals (Sweden)

    Anupama Shrivastav

    2013-01-01

    Full Text Available Drug delivery technology is emerging as an interdisciplinary science aimed at improving human health. The controlled delivery of pharmacologically active agents to the specific site of action at the therapeutically optimal rate and dose regimen has been a major goal in designing drug delivery systems. Over the past few decades, there has been considerable interest in developing biodegradable drug carriers as effective drug delivery systems. Polymeric materials from natural sources play an important role in controlled release of drug at a particular site. Polyhydroxyalkanoates, due to their origin from natural sources, are given attention as candidates for drug delivery materials. Biodegradable and biocompatible polyhydroxyalkanoates are linear polyesters produced by microorganisms under unbalanced growth conditions, which have emerged as potential polymers for use as biomedical materials for drug delivery due to their unique physiochemical and mechanical properties. This review summarizes many of the key findings in the applications of polyhydroxyalkanoates and polyhydroxyalkanoate nanoparticles for drug delivery system.

  14. Fabrication of luminescent hydroxyapatite nanorods through surface-initiated RAFT polymerization: Characterization, biological imaging and drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Heng, Chunning [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi’an, 710069 (China); Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Zheng, Xiaoyan [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi’an, 710069 (China); Liu, Meiying; Xu, Dazhuang; Huang, Hongye; Deng, Fengjie [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Hui, Junfeng, E-mail: huijunfeng@126.com [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi’an, 710069 (China); Zhang, Xiaoyong, E-mail: xiaoyongzhang1980@gmail.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Wei, Yen, E-mail: weiyen@tsinghua.edu.cn [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China)

    2016-11-15

    Highlights: • Hydrophobic hydroxyapatite nanorods were obtained from hydrothermal synthesis. • Surface initiated RAFT polymerization was adopted to surface modification of hydroxyapatite nanorods. • These modified hydroxyapatite nanorods showed high water dispersibility and biocompatibility. • These modified hydroxyapatite nanorods can be used for controlled drug delivery. - Abstract: Hydroxyapatite nanomaterials as an important class of nanomaterials, have been widely applied for different biomedical applications for their excellent biocompatibility, biodegradation potential and low cost. In this work, hydroxyapatite nanorods with uniform size and morphology were prepared through hydrothermal synthesis. The surfaces of these hydroxyapatite nanorods are covered with hydrophobic oleic acid, making them poor dispersibility in aqueous solution and difficult for biomedical applications. To overcome this issue, a simple surface initiated polymerization strategy has been developed via combination of the surface ligand exchange and reversible addition fragmentation chain transfer (RAFT) polymerization. Hydroxyapatite nanorods were first modified with Riboflavin-5-phosphate sodium (RPSSD) via ligand exchange reaction between the phosphate group of RPSSD and oleic acid. Then hydroxyl group of nHAp-RPSSD was used to immobilize chain transfer agent, which was used as the initiator for surface-initiated RAFT polymerization. The nHAp-RPSSD-poly(IA-PEGMA) nanocomposites were characterized by means of {sup 1}H nuclear magnetic resonance, Fourier transform infrared spectroscopy, fluorescence spectroscopy and thermal gravimetric analysis in detailed. The biocompatibility, biological imaging and drug delivery of nHAp-RPSSD-poly(IA-PEGMA) were also investigated. Results showed that nHAp-RPSSD-poly(IA-PEGMA) exhibited excellent water dispersibility, desirable optical properties, good biocompatibility and high drug loading capability, making them promising candidates for

  15. Fabrication of luminescent hydroxyapatite nanorods through surface-initiated RAFT polymerization: Characterization, biological imaging and drug delivery applications

    International Nuclear Information System (INIS)

    Heng, Chunning; Zheng, Xiaoyan; Liu, Meiying; Xu, Dazhuang; Huang, Hongye; Deng, Fengjie; Hui, Junfeng; Zhang, Xiaoyong; Wei, Yen

    2016-01-01

    Highlights: • Hydrophobic hydroxyapatite nanorods were obtained from hydrothermal synthesis. • Surface initiated RAFT polymerization was adopted to surface modification of hydroxyapatite nanorods. • These modified hydroxyapatite nanorods showed high water dispersibility and biocompatibility. • These modified hydroxyapatite nanorods can be used for controlled drug delivery. - Abstract: Hydroxyapatite nanomaterials as an important class of nanomaterials, have been widely applied for different biomedical applications for their excellent biocompatibility, biodegradation potential and low cost. In this work, hydroxyapatite nanorods with uniform size and morphology were prepared through hydrothermal synthesis. The surfaces of these hydroxyapatite nanorods are covered with hydrophobic oleic acid, making them poor dispersibility in aqueous solution and difficult for biomedical applications. To overcome this issue, a simple surface initiated polymerization strategy has been developed via combination of the surface ligand exchange and reversible addition fragmentation chain transfer (RAFT) polymerization. Hydroxyapatite nanorods were first modified with Riboflavin-5-phosphate sodium (RPSSD) via ligand exchange reaction between the phosphate group of RPSSD and oleic acid. Then hydroxyl group of nHAp-RPSSD was used to immobilize chain transfer agent, which was used as the initiator for surface-initiated RAFT polymerization. The nHAp-RPSSD-poly(IA-PEGMA) nanocomposites were characterized by means of "1H nuclear magnetic resonance, Fourier transform infrared spectroscopy, fluorescence spectroscopy and thermal gravimetric analysis in detailed. The biocompatibility, biological imaging and drug delivery of nHAp-RPSSD-poly(IA-PEGMA) were also investigated. Results showed that nHAp-RPSSD-poly(IA-PEGMA) exhibited excellent water dispersibility, desirable optical properties, good biocompatibility and high drug loading capability, making them promising candidates for biological

  16. Applications of nanodiamonds in drug delivery and catalysis

    KAUST Repository

    Moosa, Basem; Fhayli, Karim; Li, Song; Julfakyan, Khachatur; Ezzeddine, Alaa; Khashab, Niveen M.

    2014-01-01

    The interest of researchers in utilizing nanomaterials as carriers for a wide spectrum of molecules has exploded in the last two decades. Nanodiamonds are one class of carbon-based nanomaterials that have emerged as promising drug delivery vehicles

  17. Facile synthesis of semi-library of low charge density cationic polyesters from poly(alkylene maleate)s for efficient local gene delivery.

    Science.gov (United States)

    Yan, Huijie; Zhu, Dingcheng; Zhou, Zhuxian; Liu, Xin; Piao, Ying; Zhang, Zhen; Liu, Xiangrui; Tang, Jianbin; Shen, Youqing

    2018-03-30

    Cationic polymers are one of the main non-viral vectors for gene therapy, but their applications are hindered by the toxicity and inefficient transfection, particularly in the presence of serum or other biological fluids. While rational design based on the current understanding of gene delivery process has produced various cationic polymers with improved overall transfection, high-throughput parallel synthesis of libraries of cationic polymers seems a more effective strategy to screen out efficacious polymers. Herein, we demonstrate a novel platform for parallel synthesis of low cationic charge-density polyesters for efficient gene delivery. Unsaturated polyester poly(alkylene maleate) (PAM) readily underwent Michael-addition reactions with various mercaptamines to produce polyester backbones with pendant amine groups, poly(alkylene maleate mercaptamine)s (PAMAs). Variations of the alkylenes in the backbone and the mercaptamines on the side chain produced PAMAs with tunable hydrophobicity and DNA-condensation ability, the key parameters dominating transfection efficiency of the resulting polymer/DNA complexes (polyplexes). A semi-library of such PAMAs was exampled from 7 alkylenes and 18 mercaptamines, from which a lead PAMA, G-1, synthesized from poly(1,4-phenylene bis(methylene) maleate) and N,N-dimethylcysteamine, showed remarkable transfection efficiency even in the presence of serum, owing to its efficient lysosome-circumventing cellular uptake. Furthermore, G-1 polyplexes efficiently delivered the suicide gene pTRAIL to intraperitoneal tumors and elicited effective anticancer activity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Vinyldisiloxanes: their synthesis, cross coupling and applications.

    Science.gov (United States)

    Sore, Hannah F; Boehner, Christine M; Laraia, Luca; Logoteta, Patrizia; Prestinari, Cora; Scott, Matthew; Williams, Katharine; Galloway, Warren R J D; Spring, David R

    2011-01-21

    During the studies towards the development of pentafluorophenyldimethylsilanes as a novel organosilicon cross coupling reagent it was revealed that the active silanolate and the corresponding disiloxane formed rapidly under basic conditions. The discovery that disiloxanes are in equilibrium with the silanolate led to the use of disiloxanes as cross coupling partners under fluoride free conditions. Our previous report focused on the synthesis and base induced cross coupling of aryl substituted vinyldisiloxanes with aryl halides; good yields and selectivities were achieved. As a continuation of our research, studies into the factors which influence the successful outcome of the cross coupling reaction with both alkyl and aryl substituted vinyldisiloxanes were examined and a proposed mechanism discussed. Further investigation into expanding the breadth and diversity of substituted vinyldisiloxanes in cross coupling was explored and applied to the synthesis of unsymmetrical trans-stilbenes and cyclic structures containing the trans-alkene architecture.

  19. Collagen like peptide bioconjugates for targeted drug delivery applications

    Science.gov (United States)

    Luo, Tianzhi

    , suggesting that the nanoparticles do not initiate inflammatory response. Endowed with specific collagen binding, controlled thermoresponsiveness, excellent cytocompatibility, and non-immune responsiveness, we believe the ELP-CLP nanoparticles are promising candidates as drug delivery vehicles for targeting collagen containing matrices. Considering the critical role of collagens in extracellular matrix and the unique ability of the CLP to target native collagens, our work offers significant opportunities for the design of collagen-like peptides and their bioconjugates for targeted application in the biomedical arena.

  20. Synthesis of PLGA-Lipid Hybrid Nanoparticles for siRNA Delivery Using the Emulsion Method PLGA-PEG-Lipid Nanoparticles for siRNA Delivery.

    Science.gov (United States)

    Wang, Lei; Griffel, Benjamin; Xu, Xiaoyang

    2017-01-01

    The effective delivery of small interfering RNA (siRNA) to tumor cells remains a challenge for applications in cancer therapy. The development of polymeric nanoparticles with high siRNA loading efficacy has shown great potential for cancer targets. Double emulsion solvent evaporation technique is a useful tool for encapsulation of hydrophilic molecules (e.g., siRNA). Here we describe a versatile platform for siRNA delivery based on PLGA-PEG-cationic lipid nanoparticles by using the double emulsion method. The resulting nanoparticles show high encapsulation efficiency for siRNA (up to 90%) and demonstrate effective downregulation of the target genes in vitro and vivo.

  1. Design and synthesis of mixed oxides nanoparticles for biofuel applications

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Senniang [Iowa State Univ., Ames, IA (United States)

    2010-05-15

    The work in this dissertation presents the synthesis of two mixed metal oxides for biofuel applications and NMR characterization of silica materials. In the chapter 2, high catalytic efficiency of calcium silicate is synthesized for transesterfication of soybean oil to biodisels. Chapter 3 describes the synthesis of a new Rh based catalyst on mesoporous manganese oxides. The new catalyst is found to have higher activity and selectivity towards ethanol. Chapter 4 demonstrates the applications of solid-state Si NMR in the silica materials.

  2. Synthesis of γ-Valerolactone from Carbohydrates and its Applications.

    Science.gov (United States)

    Zhang, Zehui

    2016-01-01

    γ-Valerolactone (GVL) is a valuable chemical intermediate that can be obtained by catalytic reduction of levulinic acid (LA) or alkyl levulinates (AL). There are many reports on the synthesis of GVL from LA or AL. However, the demand for the large-scale synthesis of GVL requires more environmentally friendly and cost-effective production processes. This article focuses on the recent advance in the synthesis of GVL from carbohydrates or lignocellulosic biomass. In addition, application of GVL as the reaction solvents, fuel additives, and as precursor for the synthesis of jet fuel and polymer monomers is also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Application of mathematical modeling in sustained release delivery systems.

    Science.gov (United States)

    Grassi, Mario; Grassi, Gabriele

    2014-08-01

    This review, presenting as starting point the concept of the mathematical modeling, is aimed at the physical and mathematical description of the most important mechanisms regulating drug delivery from matrix systems. The precise knowledge of the delivery mechanisms allows us to set up powerful mathematical models which, in turn, are essential for the design and optimization of appropriate drug delivery systems. The fundamental mechanisms for drug delivery from matrices are represented by drug diffusion, matrix swelling, matrix erosion, drug dissolution with possible recrystallization (e.g., as in the case of amorphous and nanocrystalline drugs), initial drug distribution inside the matrix, matrix geometry, matrix size distribution (in the case of spherical matrices of different diameter) and osmotic pressure. Depending on matrix characteristics, the above-reported variables may play a different role in drug delivery; thus the mathematical model needs to be built solely on the most relevant mechanisms of the particular matrix considered. Despite the somewhat diffident behavior of the industrial world, in the light of the most recent findings, we believe that mathematical modeling may have a tremendous potential impact in the pharmaceutical field. We do believe that mathematical modeling will be more and more important in the future especially in the light of the rapid advent of personalized medicine, a novel therapeutic approach intended to treat each single patient instead of the 'average' patient.

  4. Drug delivery systems and materials for wound healing applications.

    Science.gov (United States)

    Saghazadeh, Saghi; Rinoldi, Chiara; Schot, Maik; Kashaf, Sara Saheb; Sharifi, Fatemeh; Jalilian, Elmira; Nuutila, Kristo; Giatsidis, Giorgio; Mostafalu, Pooria; Derakhshandeh, Hossein; Yue, Kan; Swieszkowski, Wojciech; Memic, Adnan; Tamayol, Ali; Khademhosseini, Ali

    2018-04-05

    Chronic, non-healing wounds place a significant burden on patients and healthcare systems, resulting in impaired mobility, limb amputation, or even death. Chronic wounds result from a disruption in the highly orchestrated cascade of events involved in wound closure. Significant advances in our understanding of the pathophysiology of chronic wounds have resulted in the development of drugs designed to target different aspects of the impaired processes. However, the hostility of the wound environment rich in degradative enzymes and its elevated pH, combined with differences in the time scales of different physiological processes involved in tissue regeneration require the use of effective drug delivery systems. In this review, we will first discuss the pathophysiology of chronic wounds and then the materials used for engineering drug delivery systems. Different passive and active drug delivery systems used in wound care will be reviewed. In addition, the architecture of the delivery platform and its ability to modulate drug delivery are discussed. Emerging technologies and the opportunities for engineering more effective wound care devices are also highlighted. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Biocompatible fluorescent zein nanoparticles for simultaneous bioimaging and drug delivery application

    International Nuclear Information System (INIS)

    Girija Aswathy, Ravindran; Sivakumar, Balasubramanian; Brahatheeswaran, Dhandayudhapani; Fukuda, Takahiro; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D

    2012-01-01

    We report the synthesis of 5-fluorouracil (5-FU) loaded biocompatible fluorescent zein nanoparticles. Zein is the storage protein in corn kernels that has a variety of unique characteristics and functionalities that makes zein valuable in various commercial applications. It is classified as generally recognized as safe (GRAS) by the Food and Drug Administration (FDA). We synthesized zein nanoparticles of around 800 nm in size and conjugated with quantum dot ZnS:Mn. The nanoparticle was in turn encapsulated with the drug 5-FU. The luminescent properties of these nanoparticles were studied by using fluorescence microscopy. The nanoparticles were characterized and the drug release profile was studied. The biocompatibility of zein nanoparticle and the cytotoxicity with drug-loaded nanoparticle was studied in L929 and MCF-7 cell lines. The nanoparticles were successfully employed for cellular imaging. In vitro drug release studies were also performed. The biocompatibility of the nanoparticle showed that nanoparticles at higher concentrations are compatible for cells and are expected to be promising agents for the targeted delivery of drugs in the near future

  6. Poly (DL-lactide-co-glycolide) (PLGA) nanoparticles with entrapped trans-cinnamaldehyde and eugenol for antimicrobial delivery applications.

    Science.gov (United States)

    Gomes, Carmen; Moreira, Rosana G; Castell-Perez, Elena

    2011-03-01

    Eugenol and trans-cinnamaldehyde are natural compounds known to be highly effective antimicrobials; however, both are hydrophobic molecules, a limitation to their use within the food industry. The goal of this study was to synthesize spherical poly (DL-lactide-co-glycolide) (PLGA) nanoparticles with entrapped eugenol and trans-cinnamaldehyde for future antimicrobial delivery applications. The emulsion evaporation method was used to form the nanoparticles in the presence of poly (vinyl alcohol) (PVA) as a surfactant. The inclusion of antimicrobial compounds into the PLGA nanoparticles was accomplished in the organic phase. Synthesis was followed by ultrafiltration (performed to eliminate the excess of PVA and antimicrobial compound) and freeze-drying. The nanoparticles were characterized by their shape, size, entrapment efficiency, and antimicrobial efficiency. The entrapment efficiency for eugenol and trans-cinnamaldehyde was approximately 98% and 92%, respectively. Controlled release experiments conducted in vitro at 37 °C and 100 rpm for 72 h showed an initial burst followed by a slower rate of release of the antimicrobial entrapped inside the PLGA matrix. All loaded nanoparticles formulations proved to be efficient in inhibiting growth of Salmonella spp. (Gram-negative bacterium) and Listeria spp. (Gram-positive bacterium) with concentrations ranging from 20 to 10 mg/mL. Results suggest that the application of these antimicrobial nanoparticles in food systems may be effective at inhibiting specific pathogens. Nanoencapsulation of lipophilic antimicrobial compounds has great potential for improving the effectiveness and efficiency of delivery in food systems. This study consisted of synthesizing PLGA nanoparticles with entrapped eugenol and trans-cinnamaldehyde. By characterizing these new delivery systems, one can understand the controlled-release mechanism and antimicrobial efficiency that provides a foundation that will enable food manufacturers to design

  7. Synthesis and in vitro characterization of entirely S-protected thiolated pectin for drug delivery.

    Science.gov (United States)

    Hintzen, Fabian; Hauptstein, Sabine; Perera, Glen; Bernkop-Schnürch, Andreas

    2013-11-01

    The study was aimed to synthesize a thiolated polymer (thiomer) that is resistant to oxidation in solutions above pH 5. In order to protect a pectin-cysteine conjugate against premature oxidation, the thiomer was S-protected by a disulfide connected leaving group. Therefore, 2-mercaptonicotinic acid was first coupled to L-cysteine by a disulfide exchange reaction and the purified product was subsequently attached to pectin by a carbodiimide mediated amid bond formation. The obtained fully S-protected thiolated pectin was in vitro characterized with respect to co- and mucoadhesive properties and stability toward oxidation. The results indicated a 1.8-fold and 2.3-fold enhanced disintegration time at pH 6.8 of the S-protected thiolated pectin (Pec-Cys-MNA) compared to thiolated pectin (Pec-Cys) and unmodified pectin (Pec). Moreover, rheological measurements of polymer/mucus mixtures showed a 1.6-fold (compared to Pec-Cys) and 6.7-fold (compared to Pec) increased dynamic viscosity of Pec-Cys-MNA. On the other hand, in the presence of a strong oxidizing agent such as H2O2 (0.3% v/v), no increase in viscosity of Pec-Cys-MNA could be observed. A 6-month experiment also demonstrated the long-term stability of a liquid formulation based on Pec-Cys-MNA. Further investigations proved that the first time all thiol groups on a thiolated polymer could be protected owing to the novel synthesis. Accordingly, these features may help to develop thiomer based liquid or gel formulations targeting mucosal surfaces such as nasal, ocular or vaginal drug delivery systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Sociocultural barriers to maternity services delivery: a qualitative meta-synthesis of the literature.

    Science.gov (United States)

    Sumankuuro, J; Crockett, J; Wang, S

    2018-04-01

    Maternal and neonatal healthcare outcomes in Sub-Saharan Africa (SSA) remain poor despite decades of different health service delivery interventions and stakeholder investments. Qualitative studies have attributed these results, at least in part, to sociocultural beliefs and practices. Thus there is a need to understand, from an overarching perspective, how these sociocultural beliefs affect maternal and neonatal health (MNH) outcomes. A qualitative meta-synthesis of primary studies on cultural beliefs and practices associated with maternal and neonatal health care was carried out, incorporating research conducted in any country within SSA, using data from men, women and health professionals gathered through focus group discussions, structured and semistructured interviews. A systematic search was carried out on seven electronic databases, Scopus, Ovid Medline, PubMed, CINAHL Plus, Humanities and Social Sciences (Informit), EMBASE and Web of Science, and on Google Scholar, using both manual and electronic methods, between 1st January 1990 and 1st January 2017. The terms 'cultural beliefs'; 'cultural beliefs AND maternal health'; 'cultural beliefs OR maternal health'; 'traditional practices' and 'maternal health' were used in the search. Key components of cultural beliefs and practices associated with adverse health outcomes on pregnancy, labour and the postnatal period were identified in five overarching factors: (a) pregnancy secrecy; (b) labour complications attributed to infidelity; (c) mothers' autonomy and reproductive services; (d) marital status, trust in traditional medicines and traditional birth attendants; and (e) intergenerational beliefs attached to the 'ordeal' of giving birth. Cultural beliefs and practices related to maternal and neonatal health care are intergenerational. Therefore, intensive community-specific education strategies to facilitate behaviour changes are required for improved MNH outcomes. Adopting practical approaches such as

  9. Recent advances on liposomal nanoparticles: synthesis, characterization and biomedical applications.

    Science.gov (United States)

    Panahi, Yunes; Farshbaf, Masoud; Mohammadhosseini, Majid; Mirahadi, Mozhdeh; Khalilov, Rovshan; Saghfi, Siamak; Akbarzadeh, Abolfazl

    2017-06-01

    Liposome is a new nanostructure for the encapsulation and delivery of bioactive agents. There are a lot of bioactive materials that could be incorporated into liposomes including cosmetics, food ingredients, and pharmaceuticals. Liposomes possess particular properties such as biocompatibility, biodegradability; accompanied by their nanosize they have potential applications in nanomedicine, cosmetics, and food industry. Nanoliposome technology offers thrilling chances for food technologists in fields including encapsulation and controlled release of food ingredients, also improved bioavailability and stability of sensitive materials. Amid numerous brilliant new drug and gene delivery systems, liposomes provide an advanced technology to carry active molecules to the specific site of action, and now days, various formulations are in clinical use. In this paper, we provide review of the main physicochemical properties of liposomes, current methods of the manufacturing and introduce some of their usage in food nanotechnology as carrier vehicles of nutrients, enzymes, and food antimicrobials and their applications as drug carriers and gene delivery agents in biomedicine.

  10. One-step shell polymerization of inorganic nanoparticles and their applications in SERS/nonlinear optical imaging, drug delivery, and catalysis.

    Science.gov (United States)

    Liu, Tzu-Ming; Yu, Jiashing; Chang, C Allen; Chiou, Arthur; Chiang, Huihua Kenny; Chuang, Yu-Chun; Wu, Cheng-Han; Hsu, Che-Hao; Chen, Po-An; Huang, Chih-Chia

    2014-07-07

    Surface functionalized nanoparticles have found their applications in several fields including biophotonics, nanobiomedicine, biosensing, drug delivery, and catalysis. Quite often, the nanoparticle surfaces must be post-coated with organic or inorganic layers during the synthesis before use. This work reports a generally one-pot synthesis method for the preparation of various inorganic-organic core-shell nanostructures (Au@polymer, Ag@polymer, Cu@polymer, Fe3O4@polymer, and TiO2@polymer), which led to new optical, magnetic, and catalytic applications. This green synthesis involved reacting inorganic precursors and poly(styrene-alt-maleic acid). The polystyrene blocks separated from the external aqueous environment acting as a hydrophobic depot for aromatic drugs and thus illustrated the integration of functional nanoobjects for drug delivery. Among these nanocomposites, the Au@polymer nanoparticles with good biocompatibility exhibited shell-dependent signal enhancement in the surface plasmon resonance shift, nonlinear fluorescence, and surface-enhanced Raman scattering properties. These unique optical properties were used for dual-modality imaging on the delivery of the aromatic photosensitizer for photodynamic therapy to HeLa cells.

  11. The application of nanomaterials in controlled drug delivery for bone regeneration.

    Science.gov (United States)

    Shi, Shuo; Jiang, Wenbao; Zhao, Tianxiao; Aifantis, Katerina E; Wang, Hui; Lin, Lei; Fan, Yubo; Feng, Qingling; Cui, Fu-zhai; Li, Xiaoming

    2015-12-01

    Bone regeneration is a complicated process that involves a series of biological events, such as cellular recruitment, proliferation and differentiation, and so forth, which have been found to be significantly affected by controlled drug delivery. Recently, a lot of research studies have been launched on the application of nanomaterials in controlled drug delivery for bone regeneration. In this article, the latest research progress in this area regarding the use of bioceramics-based, polymer-based, metallic oxide-based and other types of nanomaterials in controlled drug delivery for bone regeneration are reviewed and discussed, which indicates that the controlling drug delivery with nanomaterials should be a very promising treatment in orthopedics. Furthermore, some new challenges about the future research on the application of nanomaterials in controlled drug delivery for bone regeneration are described in the conclusion and perspectives part. Copyright © 2015 Wiley Periodicals, Inc.

  12. Sustained delivery of biomolecules from gelatin carriers for applications in bone regeneration.

    Science.gov (United States)

    Song, Jiankang; Leeuwenburgh, Sander Cg

    2014-08-01

    Local delivery of therapeutic biomolecules to stimulate bone regeneration has matured considerably during the past decades, but control over the release of these biomolecules still remains a major challenge. To this end, suitable carriers that allow for tunable spatial and temporal delivery of biomolecules need to be developed. Gelatin is one of the most widely used natural polymers for the controlled and sustained delivery of biomolecules because of its biodegradability, biocompatibility, biosafety and cost-effectiveness. The current study reviews the applications of gelatin as carriers in form of bulk hydrogels, microspheres, nanospheres, colloidal gels and composites for the programmed delivery of commonly used biomolecules for applications in bone regeneration with a specific focus on the relationship between carrier properties and delivery characteristics.

  13. Synthesis and applications of radiolabelled drugs in pharmaceutical development

    International Nuclear Information System (INIS)

    Landvatter, S.W.; Heys, J.R.; Garner, K.T.; Mack, J.F.; Senderoff, S.G.; Shu, A.Y.; Villani, A.J.; Saunders, D.

    1994-01-01

    Radiolabelled drugs play a vital role in the development of new pharmaceuticals including application in drug discovery, pre-clinical development and clinical development. The synthesis of these pharmaceuticals in tritium or carbon-14 labelled form poses many challenges for the synthetic organic chemist. The actual choice of synthetic route must take into account the small scale, limited choice and high cost of labelled precursors, and the positioning of the label into a metabolically stable position. There are, however, a number of synthetic strategies available for overcoming these constraints. Although in some C-14 syntheses the requisite labelled raw material can be purchased and the existing synthesis adapted for labelling, frequently the synthetic challenge is the synthesis of a structurally simple, yet commercially unavailable, labelled precursor (e.g., γ-butyrolactone-[2- 14 C], cyclohexanone-[ 3 H], CuCN-[ 14 C], 2-furancarboxaldehyde-[ 14 C]). Another useful strategy in C-14 synthesis is the conversion of an advanced intermediate, or perhaps the unlabelled product itself, into a precursor which can then be reconverted into the labelled version of the intermediate. Occasionally, a new total synthesis must be developed. In addition to these strategies, tritium labelling can uniquely take advantage of exchange labelling techniques, synthesis and reduction of unsaturated precursors, or tritium-halogen replacement reactions. Examples of these strategies and use of the labelled products are discussed

  14. Catalytic asymmetric synthesis of enantiopure isoprenoid building blocks : application in the synthesis of apple leafminer pheromones

    NARCIS (Netherlands)

    Summeren, Ruben P. van; Reijmer, Sven J.W.; Minnaard, Adriaan J.; Feringa, Bernard

    2005-01-01

    The first catalytic asymmetric procedure capable of preparing all 4 diastereoisomers (ee > 99%, de > 98%) of a versatile saturated isoprenoid building block was developed and the value of this new method was demonstrated in its application to the concise total synthesis of two pheromones.

  15. Synthesis and applications of 13C glycerol

    International Nuclear Information System (INIS)

    Stocking, E.; Khalsa, O.; Martinez, R.; Silks, L.A. III

    1994-01-01

    The authors are currently developing new synthetic routes to the various isotopomers of glycerol. Labeled glycerol is useful for 13 C enrichment of biomolecules. However, traditional methods of glycerol synthesis are not easily adapted for isotopic enrichment or have poor overall yields (12-15%). In addition, the use of glycerol for enrichment can be prohibitively expensive and its availability depends on the level of demand. The authors have developed a short de novo synthesis of [U- 13 C]glycerol from carbon dioxide (∼53% overall yield for four steps) and are currently examining the feasibility of synthesizing site-specific 13 C labeled glycerol and dihydroxyacetone (DHA) from methanol and carbon dioxide. The authors have examined the enzymatic conversion of [U- 13 C]glycerol to glyceraldehyde-3-monophosphate or dihydroxyacetone monophosphate (DHAP) with yields ranging from 25-50% (as determined by NMR spectroscopy). The authors are also pursuing the chemical conversion of 13 C labeled DHA to DHAP and the results are presented. Labeled DHAP is a possible enzymatic precursor for both labeled 2-deoxyribose and 2-deoxyribonucleic acids

  16. Design, development and characterization of multi-functionalized gold nanoparticles for biodetection and targeted boron delivery in BNCT applications.

    NARCIS (Netherlands)

    Mandal, S.; Bakeine, G.J.; Krol, S.; Ferrari, C.; Clerici, A.M.; Zonta, C.; Cansolino, L.; Ballarini, F.; Bortolussi, S.; Stella, S.; Protti, N.; Bruschi, P.; Altieri, S.

    2011-01-01

    The aim of this study is to optimize targeted boron delivery to cancer cells and its tracking down to the cellular level. To this end, we describe the design and synthesis of novel nanovectors that double as targeted boron delivery agents and fluorescent imaging probes. Gold nanoparticles were

  17. Application of social media to library service delivery: Perception of ...

    African Journals Online (AJOL)

    The study revealed that few of the social media identified are rarely relevant to library service delivery. Reference services, current awareness services, and library news postings were the types of library services that social media are applied. Results also indicated that there were benefits derived from using social media in ...

  18. Excimer laser beam delivery systems for medical applications

    Science.gov (United States)

    Kubo, Uichi; Hashishin, Yuichi; Okada, Kazuyuki; Tanaka, Hiroyuki

    1993-05-01

    We have been doing the basic experiments of UV laser beams and biotissue interaction with both KrF and XeCl lasers. However, the conventional optical fiber can not be available for power UV beams. So we have been investigating about UV power beam delivery systems. These experiments carry on with the same elements doped quartz fibers and the hollow tube. The doped elements are OH ion, chlorine and fluorine. In our latest work, we have tried ArF excimer laser and biotissue interactions, and the beam delivery experiments. From our experimental results, we found that the ArF laser beam has high incision ability for hard biotissue. For example, in the case of the cow's bone incision, the incision depth by ArF laser was ca.15 times of KrF laser. Therefore, ArF laser would be expected to harden biotissue therapy as non-thermal method. However, its beam delivery is difficult to work in this time. We will develop ArF laser beam delivery systems.

  19. DSP Based System for Real time Voice Synthesis Applications Development

    OpenAIRE

    Arsinte, Radu; Ferencz, Attila; Miron, Costin

    2008-01-01

    This paper describes an experimental system designed for development of real time voice synthesis applications. The system is composed from a DSP coprocessor card, equipped with an TMS320C25 or TMS320C50 chip, voice acquisition module (ADDA2),host computer (IBM-PC compatible), software specific tools.

  20. Synthesis and photovoltaic application of coper (I) sulfide nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yue; Wadia, Cyrus; Ma, Wanli; Sadtler, Bryce; Alivisatos, A.Paul

    2008-06-24

    We present the rational synthesis of colloidal copper(I) sulfide nanocrystals and demonstrate their application as an active light absorbing component in combination with CdS nanorods to make a solution-processed solar cell with 1.6percent power conversion efficiency on both conventional glass substrates and flexible plastic substrates with stability over a 4 month testing period.

  1. Film grain synthesis and its application to re-graining

    Science.gov (United States)

    Schallauer, Peter; Mörzinger, Roland

    2006-01-01

    Digital film restoration and special effects compositing require more and more automatic procedures for movie regraining. Missing or inhomogeneous grain decreases perceived quality. For the purpose of grain synthesis an existing texture synthesis algorithm has been evaluated and optimized. We show that this algorithm can produce synthetic grain which is perceptually similar to a given grain template, which has high spatial and temporal variation and which can be applied to multi-spectral images. Furthermore a re-grain application framework is proposed, which synthesises based on an input grain template artificial grain and composites this together with the original image content. Due to its modular approach this framework supports manual as well as automatic re-graining applications. Two example applications are presented, one for re-graining an entire movie and one for fully automatic re-graining of image regions produced by restoration algorithms. Low computational cost of the proposed algorithms allows application in industrial grade software.

  2. Carbon Onions: Synthesis and Electrochemical Applications

    Energy Technology Data Exchange (ETDEWEB)

    McDonough, John K. [Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering; Gogotsi, Y. [Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering

    2013-01-01

    Onion-like carbon structures have been synthesized in many ways and large scale production is currently under study. The annealing method can satisfy the need for large scale production, though the ideal spherical shape is unachievable, and the temperature attainable in this method is not sufficient for treating the entire particle. The arc-discharge method provides an alternate pathway toward large scale synthesis. Due to its structure and electrochemical properties, carbon onions can be used as materials for electrochemical double layer capacitors (EDLC) and can be used to store energy across a much wider temperature range, which gives these materials advantages over conventional EDLCs. This and other aspects of carbon onions are discussed in this article.

  3. Synthesis, Properties Characterization and Applications of Various Organobismuth Compounds

    Directory of Open Access Journals (Sweden)

    Jingfei Luan

    2011-05-01

    Full Text Available Organobismuth chemistry was emphasized in this review article due to the low price, low toxicity and low radioactivity characteristics of bismuth. As an environmentally-friendly class of organometallic compounds, different types of organobismuth compounds have been used in organic synthesis, catalysis, materials, etc. The synthesis and property characterization of many organobismuth compounds had been summarized. This review article also presented a survey of various applications of organobismuth compounds in organic transformations, as reagents or catalysts. The reactivity, reaction pathways and mechanisms of reactions with organobismuths were discussed. Less common and limiting aspects of organobismuth compounds were also briefly mentioned.

  4. Applications of nanodiamonds in drug delivery and catalysis.

    Science.gov (United States)

    Moosa, Basem; Fhayli, Karim; Li, Song; Julfakyan, Khatchatur; Ezzeddine, Alaa; Khashab, Niveen M

    2014-01-01

    The interest of researchers in utilizing nanomaterials as carriers for a wide spectrum of molecules has exploded in the last two decades. Nanodiamonds are one class of carbon-based nanomaterials that have emerged as promising drug delivery vehicles and imaging probes. Their ease of functionalization also led to the generation of stimuli-responsive nanodiamonds that deliver drugs on demand in a controlled manner. The ample surface area of NDs allowed for a higher loading of not only small molecules but also macromolecules like genes and proteins. Recently, the unique surface of NDs has attracted more attention as catalyst support in a huge range of organic modification and C-C bond formation reactions. Herein, recent advances in the utilization of nanodiamonds as a drug delivery vehicle and catalytical support are highlighted and summarized to illustrate the potential and versatility of this cheap and commercially available nanomaterial.

  5. Microneedle delivery: clinical studies and emerging medical applications.

    Science.gov (United States)

    Pettis, Ronald J; Harvey, Alfred J

    2012-03-01

    The concept of microneedle drug delivery was described three decades ago; however, effective clinical demonstration has only occurred within the past 10-15 years. Substantial progress in microneedle design and fabrication including extensive in vitro, ex vivo, and in vivo preclinical evaluation with various drugs, vaccines and other agents has transpired over the last decade. In contrast with this large volume of preclinical data, there are relatively few published microneedle clinical studies. To date, the clinical investigative focus has included testing to reduce dermal barrier properties and enhance transdermal delivery; evaluation of enhanced vaccine antigenicity, including development of the first commercial microneedle product for intradermal influenza vaccination; evaluation of altered microneedle protein pharmacokinetics and pharmacodynamics, especially for insulin; and evaluation of the pain and other perceptions associated with microneedle usage. This review summarizes the various aspects of microneedle clinical evaluation to date and identifies areas requiring further clinical evaluation.

  6. Applications of nanodiamonds in drug delivery and catalysis

    KAUST Repository

    Moosa, Basem

    2014-01-01

    The interest of researchers in utilizing nanomaterials as carriers for a wide spectrum of molecules has exploded in the last two decades. Nanodiamonds are one class of carbon-based nanomaterials that have emerged as promising drug delivery vehicles and imaging probes. Their ease of functionalization also led to the generation of stimuli-responsive nanodiamonds that deliver drugs on demand in a controlled manner. The ample surface area of NDs allowed for a higher loading of not only small molecules but also macromolecules like genes and proteins. Recently, the unique surface of NDs has attracted more attention as catalyst support in a huge range of organic modification and C-C bond formation reactions. Herein, recent advances in the utilization of nanodiamonds as a drug delivery vehicle and catalytical support are highlighted and summarized to illustrate the potential and versatility of this cheap and commercially available nanomaterial. Copyright © 2014 American Scientific Publishers All rights reserved.

  7. Application of Ferriferous Oxide Modified by Chitosan in Gene Delivery

    Directory of Open Access Journals (Sweden)

    Yu Kuang

    2012-01-01

    Full Text Available New approaches to improve the traditional gene carriers are still required. Here we explore Fe3O4 modified with degradable polymers that enhances gene delivery and target delivery using permanent magnetic field. Two magnetic Fe3O4 nanoparticles coated with chitosan (CTS and polyethylene glycol (PEG were synthesized by means of controlled chemical coprecipitation. Plasmid pEGFP was encapsulated as a reported gene. The ferriferous oxide complexes were approximately spherical; surface charge of CTS-Fe3O4 and PEG-Fe3O4 was about 20 mv and 0 mv, respectively. The controlled release of DNA from the CTS-Fe3O4 nanoparticles was observed. Concurrently, a desired Fe3O4 concentration of less than 2 mM was verified as safe by means of a cytotoxicity test in vitro. Presence of the permanent magnetic field significantly increased the transfection efficiency. Furthermore, the passive target property and safety of magnetic nanoparticles were also demonstrated in an in vivo test. The novel gene delivery system was proved to be an effective tool required for future target expression and gene therapy in vivo.

  8. Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

    Directory of Open Access Journals (Sweden)

    Stephen Hill

    2017-04-01

    Full Text Available Fluorescent carbon dots (FCDs are an emerging class of nanomaterials made from carbon sources that have been hailed as potential non-toxic replacements to traditional semiconductor quantum dots (QDs. Particularly in the areas of live imaging and drug delivery, due to their water solubility, low toxicity and photo- and chemical stability. Carbohydrates are readily available chiral biomolecules in nature which offer an attractive and cheap starting material from which to synthesise FCDs with distinct features and interesting applications. This mini-review article will cover the progress in the development of FCDs prepared from carbohydrate sources with an emphasis on their synthesis, functionalization and technical applications, including discussions on current challenges.

  9. Polymer nanotube nanocomposites: synthesis, properties, and applications

    National Research Council Canada - National Science Library

    Mittal, Vikas

    2010-01-01

    ... insights for the use of technologies for polymer nanocomposites for commercial application, and features chapters from the most experienced researches in the field"-- "The purpose of this edited book...

  10. Upconversion Nanomaterials: Synthesis, Mechanism, and Applications in Sensing

    Directory of Open Access Journals (Sweden)

    Julia Xiaojun Zhao

    2012-02-01

    Full Text Available Upconversion is an optical process that involves the conversion of lower-energy photons into higher-energy photons. It has been extensively studied since mid-1960s and widely applied in optical devices. Over the past decade, high-quality rare earth-doped upconversion nanoparticles have been successfully synthesized with the rapid development of nanotechnology and are becoming more prominent in biological sciences. The synthesis methods are usually phase-based processes, such as thermal decomposition, hydrothermal reaction, and ionic liquids-based synthesis. The main difference between upconversion nanoparticles and other nanomaterials is that they can emit visible light under near infrared irradiation. The near infrared irradiation leads to low autofluorescence, less scattering and absorption, and deep penetration in biological samples. In this review, the synthesis of upconversion nanoparticles and the mechanisms of upconversion process will be discussed, followed by their applications in different areas, especially in the biological field for biosensing.

  11. Complex Hollow Nanostructures: Synthesis and Energy-Related Applications.

    Science.gov (United States)

    Yu, Le; Hu, Han; Wu, Hao Bin; Lou, Xiong Wen David

    2017-04-01

    Hollow nanostructures offer promising potential for advanced energy storage and conversion applications. In the past decade, considerable research efforts have been devoted to the design and synthesis of hollow nanostructures with high complexity by manipulating their geometric morphology, chemical composition, and building block and interior architecture to boost their electrochemical performance, fulfilling the increasing global demand for renewable and sustainable energy sources. In this Review, we present a comprehensive overview of the synthesis and energy-related applications of complex hollow nanostructures. After a brief classification, the design and synthesis of complex hollow nanostructures are described in detail, which include hierarchical hollow spheres, hierarchical tubular structures, hollow polyhedra, and multi-shelled hollow structures, as well as their hybrids with nanocarbon materials. Thereafter, we discuss their niche applications as electrode materials for lithium-ion batteries and hybrid supercapacitors, sulfur hosts for lithium-sulfur batteries, and electrocatalysts for oxygen- and hydrogen-involving energy conversion reactions. The potential superiorities of complex hollow nanostructures for these applications are particularly highlighted. Finally, we conclude this Review with urgent challenges and further research directions of complex hollow nanostructures for energy-related applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Synthesis and characterization of iron based nanoparticles for novel applications

    Science.gov (United States)

    Khurshid, Hafsa

    The work in this thesis has been focused on the fabrication and characterization of iron based nanoparticles with controlled size and morphology with the aim: (i) to investigate their properties for potential applications in MICR toners and biomedical field and (ii) to study finite size effects on the magnetic properties of the nanoparticles. For the biomedical applications, core/shell structured iron/iron-oxide and hollow shell nanoparticles were synthesized by thermal decomposition of iron organometallic compounds [Fe(CO)5] at high temperature. Core/shell structured iron/iron-oxide nanoparticles have been prepared in the presence of oleic acid and oleylamine. Particle size and composition was controlled by varying the reaction parameters during synthesis. The as-made particles are hydrophobic and not dispersible in water. Water dispersibility was achieved by ligand exchange a with double hydrophilic diblock copolymer. Relaxometery measurements of the transverse relaxation time T2 of the nanoparticles solution at 3 Tesla confirm that the core/shell nanoparticles are an excellent MRI contrast agent using T2 weighted imaging sequences. In comparison to conventionally used iron oxide nanoparticles, iron/iron-oxide core/shell nanoparticles offer four times stronger T2 shortening effect at comparable core size due to their higher magnetization. The magnetic properties were studied as a function of particle size, composition and morphology. Hollow nanostructures are composed of randomly oriented grains arranged together to make a shell layer and make an interesting class of materials. The hollow morphology can be used as an extra degree of freedom to control the magnetic properties. Owing to their hollow morphology, they can be used for the targeted drug delivery applications by filling the drug inside their cavity. For the magnetic toners applications, particles were synthesized by chemically reducing iron salt using sodium borohydride and then coated with polyethylene

  13. Organic nanomaterials: synthesis, characterization, and device applications

    CERN Document Server

    Torres, Tomas

    2013-01-01

    Recent developments in nanoscience and nanotechnology have given rise to a new generation of functional organic nanomaterials with controlled morphology and well-defined properties, which enable a broad range of useful applications. This book explores some of the most important of these organic nanomaterials, describing how they are synthesized and characterized. Moreover, the book explains how researchers have incorporated organic nanomaterials into devices for real-world applications.Featuring contributions from an international team of leading nanoscientists, Organic Nanomaterials is divided into five parts:Part One introduces the fundamentals of nanomaterials and self-assembled nanostructuresPart Two examines carbon nanostructures—from fullerenes to carbon nanotubes to graphene—reporting on properties, theoretical studies, and applicationsPart Three investigates key aspects of some inorganic materials, self-assembled monolayers,...

  14. Nanoencapsulation of Insulin into Zirconium Phosphate for Oral Delivery Applications

    Science.gov (United States)

    Díaz, Agustín; David, Amanda; Pérez, Riviam; González, Millie L.; Báez, Adriana; Wark, Stacey E.; Zhang, Paul; Clearfield, Abraham; Colón, Jorge L.

    2010-01-01

    The encapsulation of insulin into different kinds of materials for non-invasive delivery is an important field of study because of the many drawbacks of painful needle and syringe delivery such as physiological stress, infection, and local hypertrophy, among others.1 A stable, robust, non-toxic, and viable non-invasive carrier for insulin delivery is needed. We present a new approach for protein nanoencapsulation using layered zirconium phosphate (ZrP) nanoparticles produced without any preintercalator present. The use of ZrP without preintercalators produces a highly pure material, without any kinds of contaminants, such as the preintercalator, which can be noxious. Cytotoxicity cell viability in vitro experiments for the ZrP nanoparticles show that ZrP is not toxic, or harmful, in a biological environment, as previously reported for rats.2 Contrary to previous preintercalator-based methods, we show that insulin can be nanoencapsulated in ZrP if a highly hydrate phase of ZrP with an interlayer distance of 10.3 Å (10.3 Å-ZrP or θ-ZrP) is used as precursor. The intercalation of insulin into ZrP produced a new insulin-intercalated ZrP phase with a ca. 27 Å interlayer distance, as determined by X-ray powder diffraction, demonstrating a successful nanoencapsulation of the hormone. The in vitro release profile of the hormone after the intercalation was determined and circular dichroism was used to study the hormone stability upon intercalation and release. The insulin remains stable in the layered material, at room temperature, for a considerable amount of time, improving the shell life of the peptidic hormone. This type of materials represents a strong candidate to develop a non-invasive insulin carrier for the treatment of diabetes mellitus. PMID:20707305

  15. 78 FR 53712 - Surface Transportation Project Delivery Program Application Requirements

    Science.gov (United States)

    2013-08-30

    ... application, and discussion of classes of multimodal projects that may be best handled on a case-by-case basis... submissions; a paragraph discussing the joint application process; and a paragraph authorizing the Agencies to... early enough to allow for a joint application of the Secretary's responsibilities before the...

  16. Carbon Nanotube Arrays for Intracellular Delivery and Biological Applications

    Science.gov (United States)

    Golshadi, Masoud

    Introducing nucleic acids into mammalian cells is a crucial step to elucidate biochemical pathways, modify gene expression in immortalized cells, primary cells, and stem cells, and intoduces new approaches for clinical diagnostics and therapeutics. Current gene transfer technologies, including lipofection, electroporation, and viral delivery, have enabled break-through advances in basic and translational science to enable derivation and programming of embryonic stem cells, advanced gene editing using CRISPR (Clustered regularly interspaced short palindromic repeats), and development of targeted anti-tumor therapy using chimeric antigen receptors in T-cells (CAR-T). Despite these successes, current transfection technologies are time consuming and limited by the inefficient introduction of test molecules into large populations of target cells, and the cytotoxicity of the techniques. Moreover, many cell types cannot be consistently transfected by lipofection or electroporation (stem cells, T-cells) and viral delivery has limitations to the size of experimental DNA that can be packaged. In this dissertation, a novel coverslip-like platform consisting of an array of aligned hollow carbon nanotubes (CNTs) embedded in a sacrificial template is developed that enhances gene transfer capabilities, including high efficiency, low toxicity, in an expanded range of target cells, with the potential to transfer mixed combinations of protein and nucleic acids. The CNT array devices are fabricated by a scalable template-based manufacturing method using commercially available membranes, eliminating the need for nano-assembly. High efficient transfection has been demonstrated by delivering various cargos (nanoparticles, dye and plasmid DNA) into populations of cells, achieving 85% efficiency of plasmid DNA delivery into immortalized cells. Moreover, the CNT-mediated transfection of stem cells shows 3 times higher efficiency compared to current lipofection methods. Evaluating the cell

  17. ATRP-based synthesis and characterization of light-responsive coatings for transdermal delivery systems

    Science.gov (United States)

    Pauly, Anja C.; Schöller, Katrin; Baumann, Lukas; Rossi, René M.; Dustmann, Kathrin; Ziener, Ulrich; de Courten, Damien; Wolf, Martin; Boesel, Luciano F.; Scherer, Lukas J.

    2015-06-01

    The grafting of poly(hydroxyethylmethacrylate) on polymeric porous membranes via atom transfer radical polymerization (ATRP) and subsequent modification with a photo-responsive spiropyran derivative is described. This method leads to photo-responsive membranes with desirable properties such as light-controlled permeability changes, exceptional photo-stability and repeatability of the photo-responsive switching. Conventional track etched polyester membranes were first treated with plasma polymer coating introducing anchoring groups, which allowed the attachment of ATRP-initiator molecules on the membrane surface. Surface initiated ARGET-ATRP of hydroxyethylmethacrylate (where ARGET stands for activator regenerated by electron transfer) leads to a membrane covered with a polymer layer, whereas the controlled polymerization procedure allows good control over the thickness of the polymer layer in respect to the polymerization conditions. Therefore, the final permeability of the membranes could be tailored by choice of pore diameter of the initial membranes, applied monomer concentration or polymerization time. Moreover a remarkable switch in permeability (more than 1000%) upon irradiation with UV-light could be achieved. These properties enable possible applications in the field of transdermal drug delivery, filtration, or sensing.

  18. ATRP-based synthesis and characterization of light-responsive coatings for transdermal delivery systems

    International Nuclear Information System (INIS)

    Pauly, Anja C; Schöller, Katrin; Baumann, Lukas; Rossi, René M; Dustmann, Kathrin; Boesel, Luciano F; Scherer, Lukas J; Ziener, Ulrich; De Courten, Damien; Wolf, Martin

    2015-01-01

    The grafting of poly(hydroxyethylmethacrylate) on polymeric porous membranes via atom transfer radical polymerization (ATRP) and subsequent modification with a photo-responsive spiropyran derivative is described. This method leads to photo-responsive membranes with desirable properties such as light-controlled permeability changes, exceptional photo-stability and repeatability of the photo-responsive switching. Conventional track etched polyester membranes were first treated with plasma polymer coating introducing anchoring groups, which allowed the attachment of ATRP-initiator molecules on the membrane surface. Surface initiated ARGET–ATRP of hydroxyethylmethacrylate (where ARGET stands for activator regenerated by electron transfer) leads to a membrane covered with a polymer layer, whereas the controlled polymerization procedure allows good control over the thickness of the polymer layer in respect to the polymerization conditions. Therefore, the final permeability of the membranes could be tailored by choice of pore diameter of the initial membranes, applied monomer concentration or polymerization time. Moreover a remarkable switch in permeability (more than 1000%) upon irradiation with UV-light could be achieved. These properties enable possible applications in the field of transdermal drug delivery, filtration, or sensing. (focus issue paper)

  19. Synthesis of Polymer-Lipid Nanoparticles by Microfluidic Focusing for siRNA Delivery

    Directory of Open Access Journals (Sweden)

    Yujing Li

    2016-10-01

    Full Text Available Polyethylenimine (PEI as a cationic polymer is commonly used as a carrier for gene delivery. PEI-800 is less toxic than PEI-25K but it is also less efficient. A novel nanocarrier was developed by combining PEI-800 with a pH-sensitive lipid to form polymer-lipid hybrid nanoparticles (P/LNPs. They were synthesized by microfluidic focusing (MF. Two microfluidic devices were used to synthesize P/LNPs loaded with VEGF siRNA. A series of P/LNPs with different particle sizes and distributions were obtained by altering the flow rate and geometry of microfluidic chips, and introducing sonication. Furthermore, the P/LNPs can be loaded with VEGF siRNA efficiently and were stable in serum for 12 h. Finally, P/LNPs produced by the microfluidic chip showed greater cellular uptake as well as down-regulation of VEGF protein level in both A549 and MCF-7 with reduced cellular toxicity. All in all, the P/LNPs produced by MF method were shown to be a safe and efficient carrier for VEGF siRNA, with potential application for siRNA therapeutics.

  20. Synthesis of Chromophores for Nonlinear Optics Applications

    Science.gov (United States)

    2010-03-12

    Investigacion de Quimica Aplicada Blvd. Enrique reyna, No. 140 Saltillo, Coahuila, Mexico 25253 AFOSR FA9550-09-1-0017 12 March 2010...PERFORMING ORGANIZATION REPORT NUMBER CENTRO DE INVESTIGACION EN QUIMICA APLICADA BLVD ENRIQUE REYNA NO 140 SALTILLO 25253 MEXICO...APPLICATIONS Eduardo Arias, Ivana Moggio and Ronald F. Ziolo Centro de Investigacion de Quimica Aplicada Saltillo, Coahuila, Mexico 25253

  1. Synthesis, properties, and applications of hydroxyapatite

    CSIR Research Space (South Africa)

    Chetty, A

    2012-08-01

    Full Text Available is its poor tensile strength and fracture toughness compared to natural bone. This makes HA unsuitable for several load-bearing applications. HA has been reinforced with a number of fillers including polymers such as collagen, metals and inorganic...

  2. Zirconium Phosphate Nanoplatelet Potential for Anticancer Drug Delivery Applications.

    Science.gov (United States)

    González, Millie L; Ortiz, Mayra; Hernández, Carmen; Cabán, Jennifer; Rodríguez, Axel; Colón, Jorge L; Báez, Adriana

    2016-01-01

    Zirconium phosphate (ZrP) nanoplatelets can intercalate anticancer agents via an ion exchange reaction creating an inorganic delivery system with potential for cancer treatment. ZrP delivery of anticancer agents inside tumor cells was explored in vitro. Internalization and cytotoxicity of ZrP nanoplatelets were studied in MCF-7 and MCF-10A cells. DOX-loaded ZrP nanoplatelets (DOX@ZrP) uptake was assessed by confocal (CLSM) and transmission electron microscopy (TEM). Cytotoxicity to MCF-7 and MCF-10A cells was determined by the MTT assay. Reactive Oxy- gen Species (ROS) production was analyzed by fluorometric assay, and cell cycle alterations and induction of apoptosis were analyzed by flow cytometry. ZrP nanoplatelets were localized in the endosomes of MCF-7 cells. DOX and ZrP nanoplatelets were co-internalized into MCF-7 cells as detected by CLSM. While ZrP showed limited toxicity to MCF-7 cells, DOX@ZrP was cytotoxic at an IC₅₀ similar to that of free DOX. Meanwhile, DOX lC₅₀ was significantly lower than the equivalent concentration of DOX@ZrP in MCF-10A cells. ZrP did not induce apoptosis in both cell lines. DOX and DOX@ZrP induced significant oxidative stress in both cell models. Results suggest that ZrP nanoplatelets are promising as carriers of anticancer agents into cancer cells.

  3. PEG-based degradable networks for drug delivery applications

    Science.gov (United States)

    Ostroha, Jamie L.

    The controlled delivery of therapeutic agents by biodegradable hydrogels has become a popular mechanism for drug administration in recent years. Hydrogels are three-dimensional networks of polymer chains held together by crosslinks. Although the changes which the hydrogel undergoes in solution are important to a wide range of experimental studies, they have not been investigated systematically and the factors which influence the degree of swelling have not been adequately described. Hydrogels made of poly(ethylene glycol) (PEG) will generally resist degradation in aqueous conditions, while a hydrogel made from a copolymer of poly(lactic acid) (PLA) and PEG will degrade via hydrolysis of the lactic acid group. This ability to degrade makes these hydrogels promising candidates for controlled release drug delivery systems. The goal of this research was to characterize the swelling and degradation of both degradable and non-degradable gels and to evaluate the release of different drugs from these hydrogels, where the key variable is the molecular weight of the PEG segment. These hydrogels were formed by the addition and subsequent chemically crosslinking of methacrylate end groups. During crosslinking, both PEG and LA-PEG-LA hydrogels of varied PEG molecular weight were loaded with Vitamin B12, Insulin, Haloperidol, and Dextran. It was shown that increasing PEG molecular weight produces a hydrogel with larger pores, thus increasing water uptake and degradation rate. While many environmental factors do not affect the swelling behavior, they do significantly impact the degradation of the hydrogel, and thus the release of incorporated therapeutic agents.

  4. Graphene Nanoelectronics Metrology, Synthesis, Properties and Applications

    CERN Document Server

    2012-01-01

    Graphene is a perfectly two-dimensional single-atom thin membrane with zero bandgap. It has attracted huge attention due to its linear dispersion around the Dirac point, excellent transport properties, novel magnetic characteristics, and low spin-orbit coupling. Graphene and its nanostructures may have potential applications in spintronics, photonics, plasmonics and electronics. This book brings together a team of experts to provide an overview of the most advanced topics in theory, experiments, spectroscopy and applications of graphene and its nanostructures. It covers the state-of-the-art in tutorial-like and review-like manner to make the book useful not only to experts, but also newcomers and graduate students.

  5. Glyco-gold nanoparticles: synthesis and applications

    OpenAIRE

    Compostella, Federica; Pitirollo, Olimpia; Silvestri, Alessandro; Polito, Laura

    2017-01-01

    Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco ...

  6. ASAM: Automatic architecture synthesis and application mapping

    DEFF Research Database (Denmark)

    Jozwiak, Lech; Lindwer, Menno; Corvino, Rosilde

    2013-01-01

    of the European project ASAM of the ARTEMIS program. The paper briefly presents the results of our analysis of the main challenges to be faced in the design of such heterogeneous MPSoCs. It explains which system, design, and electronic design automation (EDA) concepts seem to be adequate to address the challenges...... and solve the problems. Finally, it discusses the ASAM design-flow, its main stages and tools and their application to a real-life case study....

  7. Glyco-gold nanoparticles: synthesis and applications

    Directory of Open Access Journals (Sweden)

    Federica Compostella

    2017-05-01

    Full Text Available Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco nanoparticle design.

  8. Magnetic nanomaterials undamentals, synthesis and applications

    CERN Document Server

    Sellmyer, David J

    2017-01-01

    Timely and comprehensive, this book presents recent advances in magnetic nanomaterials research, covering the latest developments, including the design and preparation of magnetic nanoparticles, their physical and chemical properties as well as their applications in different fields, including biomedicine, magnetic energy storage, wave–absorbing and water remediation. By allowing researchers to get to the forefront developments related to magnetic nanomaterials in various disciplines, this is invaluable reading for the nano, magnetic, energy, medical, and environmental communities.

  9. Conducting polymer nanostructures: template synthesis and applications in energy storage.

    Science.gov (United States)

    Pan, Lijia; Qiu, Hao; Dou, Chunmeng; Li, Yun; Pu, Lin; Xu, Jianbin; Shi, Yi

    2010-07-02

    Conducting polymer nanostructures have received increasing attention in both fundamental research and various application fields in recent decades. Compared with bulk conducting polymers, conducting polymer nanostructures are expected to display improved performance in energy storage because of the unique properties arising from their nanoscaled size: high electrical conductivity, large surface area, short path lengths for the transport of ions, and high electrochemical activity. Template methods are emerging for a sort of facile, efficient, and highly controllable synthesis of conducting polymer nanostructures. This paper reviews template synthesis routes for conducting polymer nanostructures, including soft and hard template methods, as well as its mechanisms. The application of conducting polymer mesostructures in energy storage devices, such as supercapacitors and rechargeable batteries, are discussed.

  10. Conducting Polymer Nanostructures: Template Synthesis and Applications in Energy Storage

    Directory of Open Access Journals (Sweden)

    Lijia Pan

    2010-07-01

    Full Text Available Conducting polymer nanostructures have received increasing attention in both fundamental research and various application fields in recent decades. Compared with bulk conducting polymers, conducting polymer nanostructures are expected to display improved performance in energy storage because of the unique properties arising from their nanoscaled size: high electrical conductivity, large surface area, short path lengths for the transport of ions, and high electrochemical activity. Template methods are emerging for a sort of facile, efficient, and highly controllable synthesis of conducting polymer nanostructures. This paper reviews template synthesis routes for conducting polymer nanostructures, including soft and hard template methods, as well as its mechanisms. The application of conducting polymer mesostructures in energy storage devices, such as supercapacitors and rechargeable batteries, are discussed.

  11. Fundamentals and applications of organic electrochemistry synthesis, materials, devices

    CERN Document Server

    Fuchigami, Toshio; Inagi, Shinsuke

    2014-01-01

    This textbook is an accessible overview of the broad field of organic electrochemistry, covering the fundamentals and applications of contemporary organic electrochemistry.  The book begins with an introduction to the fundamental aspects of electrode electron transfer and methods for the electrochemical measurement of organic molecules. It then goes on to discuss organic electrosynthesis of molecules and macromolecules, including detailed experimental information for the electrochemical synthesis of organic compounds and conducting polymers. Later chapters highlight new methodology for organic electrochemical synthesis, for example electrolysis in ionic liquids, the application to organic electronic devices such as solar cells and LEDs, and examples of commercialized organic electrode processes. Appendices present useful supplementary information including experimental examples of organic electrosynthesis, and tables of physical data (redox potentials of various organic solvents and organic compounds and phy...

  12. Inorganic-whisker-reinforced polymer composites synthesis, properties and applications

    CERN Document Server

    Sun, Qiuju

    2015-01-01

    Inorganic-Whisker-Reinforced Polymer Composites: Synthesis, Properties and Applications gives a comprehensive presentation of inorganic microcrystalline fibers, or whiskers, a polymer composite filler. It covers whisker synthesis, surface modification, applications for reinforcing polymer-matrix composites, and analysis of resulting filled polymer composites. It focuses on calcium carbonate whiskers as a primary case study, introducing surface treatment methods for calcium carbonate whiskers and factors that influence them. Along with calcium carbonate, the book discusses potassium titanate and aluminum borate whiskers, which also comprise the new generation of inorganic whiskers. According to research results, composites filled by inorganic whiskers show improved strength, wear-resistance, thermal conductivity, and antistatic properties. It explains the importance of modifying polymer materials for use with inorganic whiskers and describes preparation and evaluation methods of polymers filled with inorganic ...

  13. Nanosilicon properties, synthesis, applications, methods of analysis and control

    CERN Document Server

    Ischenko, Anatoly A; Aslalnov, Leonid A

    2015-01-01

    Nanosilicon: Properties, Synthesis, Applications, Methods of Analysis and Control examines the latest developments on the physics and chemistry of nanosilicon. The book focuses on methods for producing nanosilicon, its electronic and optical properties, research methods to characterize its spectral and structural properties, and its possible applications. The first part of the book covers the basic properties of semiconductors, including causes of the size dependence of the properties, structural and electronic properties, and physical characteristics of the various forms of silicon. It presents theoretical and experimental research results as well as examples of porous silicon and quantum dots. The second part discusses the synthesis of nanosilicon, modification of the surface of nanoparticles, and properties of the resulting particles. The authors give special attention to the photoluminescence of silicon nanoparticles. The third part describes methods used for studying and controlling the structure and pro...

  14. Synthesis and applications of nano-structured iron oxides/hydroxides

    African Journals Online (AJOL)

    ... in numerous synthesis processes. This review outlines the work being carried out on synthesis of iron oxides in nano form and their various applications. Keywords: nano iron oxides, synthesis, catalysts, magnetic properties, biomedical application. International Journal of Engineering, Science and Technology, Vol. 2, No.

  15. Nanoporous ionic organic networks: from synthesis to materials applications

    OpenAIRE

    Sun, Jian-Ke; Antonietti, Markus; Yuan, Jiayin

    2016-01-01

    The past decade has witnessed rapid progress in the synthesis of nanoporous organic networks or polymer frameworks for various potential applications. Generally speaking, functionalization of porous networks to add extra properties and enhance materials performance could be achieved either during the pore formation (thus a concurrent approach) or by post-synthetic modification (a sequential approach). Nanoporous organic networks which include ion pairs bound in a covalent manner are of specia...

  16. Nanostructured silver sulfide: synthesis of various forms and their application

    Science.gov (United States)

    Sadovnikov, S. I.; Rempel, A. A.; Gusev, A. I.

    2018-04-01

    The results of experimental studies on nanostructured silver sulfide are analyzed and generalized. The influence of small particle size on nonstoichiometry of silver sulfide is discussed. Methods for the synthesis of various forms of nanostructured Ag2S including nanopowders, stable colloidal solutions, quantum dots, core–shell nanoparticles and heteronanostructures are described. The advantages and drawbacks of different synthetic procedures are analyzed. Main fields of application of nanostructured silver sulfide are considered. The bibliography includes 184 references.

  17. AIE Polymers: Synthesis, Properties, and Biological Applications.

    Science.gov (United States)

    Zhan, Ruoyu; Pan, Yutong; Manghnani, Purnima Naresh; Liu, Bin

    2017-05-01

    Aggregation-caused quenching (ACQ) is a general phenomenon that is faced by traditional fluorescent polymers. Aggregation-induced emission (AIE) is exactly opposite to ACQ. AIE molecules are almost nonemissive in their molecularly dissolved state, but they can be induced to show high fluorescence in the aggregated or solid state. Incorporation of AIE phenomenon into polymer design has yielded various polymers with AIE characteristics. In this review, the recent progress of AIE polymers for biological applications is summarized. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Applications of nanoparticle systems in drug delivery technology

    Directory of Open Access Journals (Sweden)

    Syed A.A. Rizvi

    2018-01-01

    Full Text Available The development of nanoparticle-based drug formulations has yielded the opportunities to address and treat challenging diseases. Nanoparticles vary in size but are generally ranging from 100 to 500 nm. Through the manipulation of size, surface characteristics and material used, the nanoparticles can be developed into smart systems, encasing therapeutic and imaging agents as well as bearing stealth property. Further, these systems can deliver drug to specific tissues and provide controlled release therapy. This targeted and sustained drug delivery decreases the drug related toxicity and increase patient’s compliance with less frequent dosing. Nanotechnology has proven beneficial in the treatment of cancer, AIDS and many other disease, also providing advancement in diagnostic testing.

  19. Plasma Synthesis of Nanoparticles for Nanocomposite Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Peter C. Kong; Alex W. Kawczak

    2008-09-01

    The nanocomposite energy applications for plasma reactor produced nanoparticles are reviewed. Nanoparticles are commonly defined as particles less than 100 nm in diameter. Due to this small size, nanoparticles have a high surface-to-volume ratio. This increases the surface energy compared to the bulk material. The high surface-to-volume ratio and size effects (quantum effects) give nanoparticles distinctive chemical, electronic, optical, magnetic and mechanical properties from those of the bulk material. Nanoparticles synthesis can be grouped into 3 broad approaches. The first one is wet phase synthesis (sol-gel processing), the second is mechanical attrition, and the third is gas-phase synthesis (aerosol). The properties of the final product may differ significantly depending on the fabrication route. Currently, there are no economical large-scale production processes for nanoparticles. This hinders the widespread applications of nanomaterials in products. The Idaho National Laboratory (INL) is engaging in research and development of advanced modular hybrid plasma reactors for low cost production of nanoparticles that is predicted to accelerate application research and enable the formation of technology innovation alliances that will result in the commercial production of nanocomposites for alternative energy production devices such as fuel cells, photovoltaics and electrochemical double layer capacitors.

  20. Application of three-dimensional printing for colon targeted drug delivery systems.

    Science.gov (United States)

    Charbe, Nitin B; McCarron, Paul A; Lane, Majella E; Tambuwala, Murtaza M

    2017-01-01

    Orally administered solid dosage forms currently dominate over all other dosage forms and routes of administrations. However, human gastrointestinal tract (GIT) poses a number of obstacles to delivery of the drugs to the site of interest and absorption in the GIT. Pharmaceutical scientists worldwide have been interested in colon drug delivery for several decades, not only for the delivery of the drugs for the treatment of colonic diseases such as ulcerative colitis and colon cancer but also for delivery of therapeutic proteins and peptides for systemic absorption. Despite extensive research in the area of colon targeted drug delivery, we have not been able to come up with an effective way of delivering drugs to the colon. The current tablets designed for colon drug release depend on either pH-dependent or time-delayed release formulations. During ulcerative colitis the gastric transit time and colon pH-levels is constantly changing depending on whether the patient is having a relapse or under remission. Hence, the current drug delivery system to the colon is based on one-size-fits-all. Fails to effectively deliver the drugs locally to the colon for colonic diseases and delivery of therapeutic proteins and peptides for systemic absorption from the colon. Hence, to overcome the current issues associated with colon drug delivery, we need to provide the patients with personalized tablets which are specifically designed to match the individual's gastric transit time depending on the disease state. Three-dimensional (3D) printing (3DP) technology is getting cheaper by the day and bespoke manufacturing of 3D-printed tablets could provide the solutions in the form of personalized colon drug delivery system. This review provides a bird's eye view of applications and current advances in pharmaceutical 3DP with emphasis on the development of colon targeted drug delivery systems.

  1. Boron Nitride Nanotube: Synthesis and Applications

    Science.gov (United States)

    Tiano, Amanda L.; Park, Cheol; Lee, Joseph W.; Luong, Hoa H.; Gibbons, Luke J.; Chu, Sang-Hyon; Applin, Samantha I.; Gnoffo, Peter; Lowther, Sharon; Kim, Hyun Jung; hide

    2014-01-01

    Scientists have predicted that carbon's immediate neighbors on the periodic chart, boron and nitrogen, may also form perfect nanotubes, since the advent of carbon nanotubes (CNTs) in 1991. First proposed then synthesized by researchers at UC Berkeley in the mid 1990's, the boron nitride nanotube (BNNT) has proven very difficult to make until now. Herein we provide an update on a catalyst-free method for synthesizing highly crystalline, small diameter BNNTs with a high aspect ratio using a high power laser under a high pressure and high temperature environment first discovered jointly by NASA/NIA JSA. Progress in purification methods, dispersion studies, BNNT mat and composite formation, and modeling and diagnostics will also be presented. The white BNNTs offer extraordinary properties including neutron radiation shielding, piezoelectricity, thermal oxidative stability (> 800 C in air), mechanical strength, and toughness. The characteristics of the novel BNNTs and BNNT polymer composites and their potential applications are discussed.

  2. Application of Fused Deposition Modelling (FDM) Method of 3D Printing in Drug Delivery.

    Science.gov (United States)

    Long, Jingjunjiao; Gholizadeh, Hamideh; Lu, Jun; Bunt, Craig; Seyfoddin, Ali

    2017-01-01

    Three-dimensional (3D) printing is an emerging manufacturing technology for biomedical and pharmaceutical applications. Fused deposition modelling (FDM) is a low cost extrusion-based 3D printing technique that can deposit materials layer-by-layer to create solid geometries. This review article aims to provide an overview of FDM based 3D printing application in developing new drug delivery systems. The principle methodology, suitable polymers and important parameters in FDM technology and its applications in fabrication of personalised tablets and drug delivery devices are discussed in this review. FDM based 3D printing is a novel and versatile manufacturing technique for creating customised drug delivery devices that contain accurate dose of medicine( s) and provide controlled drug released profiles. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Realist synthesis of educational interventions to improve nutrition care competencies and delivery by doctors and other healthcare professionals

    Science.gov (United States)

    Mogre, Victor; Scherpbier, Albert J J A; Stevens, Fred; Aryee, Paul; Cherry, Mary Gemma; Dornan, Tim

    2016-01-01

    Objective To determine what, how, for whom, why, and in what circumstances educational interventions improve the delivery of nutrition care by doctors and other healthcare professionals work. Design Realist synthesis following a published protocol and reported following Realist and Meta-narrative Evidence Synthesis: Evolving Standards (RAMESES) guidelines. A multidisciplinary team searched MEDLINE, CINAHL, ERIC, EMBASE, PsyINFO, Sociological Abstracts, Web of Science, Google Scholar and Science Direct for published and unpublished (grey) literature. The team identified studies with varied designs; appraised their ability to answer the review question; identified relationships between contexts, mechanisms and outcomes (CMOs); and entered them into a spreadsheet configured for the purpose. The final synthesis identified commonalities across CMO configurations. Results Over half of the 46 studies from which we extracted data originated from the USA. Interventions that improved the delivery of nutrition care improved skills and attitudes rather than just knowledge; provided opportunities for superiors to model nutrition care; removed barriers to nutrition care in health systems; provided participants with local, practically relevant tools and messages; and incorporated non-traditional, innovative teaching strategies. Operating in contexts where student and qualified healthcare professionals provided nutrition care in developed and developing countries, these interventions yielded health outcomes by triggering a range of mechanisms, which included feeling competent, feeling confident and comfortable, having greater self-efficacy, being less inhibited by barriers in healthcare systems and feeling that nutrition care was accepted and recognised. Conclusions These findings show how important it is to move education for nutrition care beyond the simple acquisition of knowledge. They show how educational interventions embedded within systems of healthcare can improve

  4. Synthesis and Biomedical Applications of Copper Sulfide Nanoparticles: From Sensors to Theranostics

    Science.gov (United States)

    Goel, Shreya; Chen, Feng; Cai, Weibo

    2013-01-01

    Copper sulfide (CuS) nanoparticles have attracted increasing attention from biomedical researchers across the globe, because of their intriguing properties which have been mainly explored for energy- and catalysis-related applications to date. This focused review article aims to summarize the recent progress made in the synthesis and biomedical applications of various CuS nanoparticles. After a brief introduction to CuS nanoparticles in the first section, we will provide a concise outline of the various synthetic routes to obtain different morphologies of CuS nanoparticles, which can influence their properties and potential applications. CuS nanoparticles have found broad applications in vitro, especially in the detection of biomolecules, chemicals, and pathogens which will be illustrated in detail. The in vivo uses of CuS nanoparticles have also been investigated in preclinical studies, including molecular imaging with various techniques, cancer therapy based on the photothermal properties of CuS, as well as drug delivery and theranostic applications. Research on CuS nanoparticles will continue to thrive over the next decade, and tremendous opportunities lie ahead for potential biomedical/clinical applications of CuS nanoparticles. PMID:24106015

  5. A review of the magnetic properties, synthesis methods and applications of maghemite

    Energy Technology Data Exchange (ETDEWEB)

    Shokrollahi, H., E-mail: shokrollahi@sutech.ac.ir

    2017-03-15

    It must be pointed out that maghemite (γ-Fe{sub 2}O{sub 3}) with a cubic spinel structure is a crucial material for various applications, including spin electronic devices, high-density magnetic recording, nano-medicines and biosensors. This paper has to do with a review study on the synthesis methods, magnetic properties and application of maghemite in the form of one-dimensional (1D) nanostructured materials, such as nanoparticles, nanotubes, nano-rods, and nanowires, as well as two-dimensional (2D) thin films. The results revealed that maghemite is widely used in the biomedical applications (hyperthermia, magnetic resonance imaging and drug delivery) and magnetic recording devices. The unmodified and Co/Mn modified maghemite thin films prepared by the dc-reactive magnetron sputtering show the excellent values of coercivity 2100 Oe and 3900 Oe, respectively, for the magnetic storage application. The super-paramagnetic particles with 7 nm size and the saturation magnetization of 80 emu/g prepared by the established thermolysis method are good candidates for bio-medical applications. - Highlights: • Among iron oxides, maghemite is one of the most important magnetic ceramics. • Maghemite is widely sued in magnetic recording and biomedicine. • This paper attempts to give an overview on the some important areas. • They contain synthetic methods, magnetic study, structural study and applications.

  6. [Progress in synthesis technologies and application of aviation biofuels].

    Science.gov (United States)

    Sun, Xiaoying; Liu, Xiang; Zhao, Xuebing; Yang, Ming; Liu, Dehua

    2013-03-01

    Development of aviation biofuels has attracted great attention worldwide because that the shortage of fossil resources has become more and more serious. In the present paper, the development background, synthesis technologies, current application status and existing problems of aviation biofuels were reviewed. Several preparation routes of aviation biofuels were described, including Fischer-Tropsch process, catalytic hydrogenation and catalytic cracking of bio-oil. The status of flight tests and commercial operation were also introduced. Finally the problems for development and application of aviation biofuels were stated, and some accommodation were proposed.

  7. Relational Constraint Driven Test Case Synthesis for Web Applications

    Directory of Open Access Journals (Sweden)

    Xiang Fu

    2010-09-01

    Full Text Available This paper proposes a relational constraint driven technique that synthesizes test cases automatically for web applications. Using a static analysis, servlets can be modeled as relational transducers, which manipulate backend databases. We present a synthesis algorithm that generates a sequence of HTTP requests for simulating a user session. The algorithm relies on backward symbolic image computation for reaching a certain database state, given a code coverage objective. With a slight adaptation, the technique can be used for discovering workflow attacks on web applications.

  8. Polymer-Nanoparticle Composites: From Synthesis to Modern Applications

    Directory of Open Access Journals (Sweden)

    Thomas Hanemann

    2010-05-01

    Full Text Available The addition of inorganic spherical nanoparticles to polymers allows the modification of the polymers physical properties as well as the implementation of new features in the polymer matrix. This review article covers considerations on special features of inorganic nanoparticles, the most important synthesis methods for ceramic nanoparticles and nanocomposites, nanoparticle surface modification, and composite formation, including drawbacks. Classical nanocomposite properties, as thermomechanical, dielectric, conductive, magnetic, as well as optical properties, will be summarized. Finally, typical existing and potential applications will be shown with the focus on new and innovative applications, like in energy storage systems.

  9. Gold nanocages: synthesis, properties, and applications.

    Science.gov (United States)

    Skrabalak, Sara E; Chen, Jingyi; Sun, Yugang; Lu, Xianmao; Au, Leslie; Cobley, Claire M; Xia, Younan

    2008-12-01

    Noble-metal nanocages comprise a novel class of nanostructures possessing hollow interiors and porous walls. They are prepared using a remarkably simple galvanic replacement reaction between solutions containing metal precursor salts and Ag nanostructures prepared through polyol reduction. The electrochemical potential difference between the two species drives the reaction, with the reduced metal depositing on the surface of the Ag nanostructure. In our most studied example, involving HAuCl(4) as the metal precursor, the resultant Au is deposited epitaxially on the surface of the Ag nanocubes, adopting their underlying cubic form. Concurrent with this deposition, the interior Ag is oxidized and removed, together with alloying and dealloying, to produce hollow and, eventually, porous structures that we commonly refer to as Au nanocages. This approach is versatile, with a wide range of morphologies (e.g., nanorings, prism-shaped nanoboxes, nanotubes, and multiple-walled nanoshells or nanotubes) available upon changing the shape of the initial Ag template. In addition to Au-based structures, switching the metal salt precursors to Na(2)PtCl(4) and Na(2)PdCl(4) allows for the preparation of Pt- and Pd-containing hollow nanostructures, respectively. We have found that changing the amount of metal precursor added to the suspension of Ag nanocubes is a simple means of tuning both the composition and the localized surface plasmon resonance (LSPR) of the metal nanocages. Using this approach, we are developing structures for biomedical and catalytic applications. Because discrete dipole approximations predicted that the Au nanocages would have large absorption cross-sections and because their LSPR can be tuned into the near-infrared (where the attenuation of light by blood and soft tissue is greatly reduced), they are attractive materials for biomedical applications in which the selective absorption of light at great depths is desirable. For example, we have explored their

  10. CODE-RADE - Community Infrastructure for the Delivery of Physics Applications

    OpenAIRE

    Becker, Bruce; Murray, Sean

    2017-01-01

    Scientific computing can in some sense be distilled to the execution of an application - or rather sets of applications which are combined into complex workflows. Due to the complexity and number both of scientific packages as well as computing platforms, delivering these applications to end users has always been a significant challenge through the grid era, and remains so in the cloud era. In this contribution we describe a platform for user-driven, continuous integration and delivery of res...

  11. Nanoscale Nutrient Delivery Systems for Food Applications: Improving Bioactive Dispersibility, Stability, and Bioavailability.

    Science.gov (United States)

    McClements, David Julian

    2015-07-01

    There has been a surge of interest in the development of nanoscale systems for the encapsulation, protection, and delivery of lipophilic nutrients, vitamins, and nutraceuticals. This review article highlights the challenges associated with incorporating these lipophilic bioactive components into foods, and then discusses potential nanoscale delivery systems that can be used to overcome these challenges. In particular, the desirable characteristics required for any nanoscale delivery system are presented, as well as methods of fabricating them and of characterizing them. An overview of different delivery systems is given, such as microemulsions, nanoemulsions, emulsions, microgels, and biopolymer nanoparticles, and their potential applications are discussed. Nanoscale delivery systems have considerable potential within the food industry, but they must be carefully formulated to ensure that they are safe, economically viable, and effective. Nanoscale delivery systems have numerous potential applications in the food industry for encapsulating, protecting, and releasing bioactive agents, such as nutraceuticals and vitamins. This review article highlights methods for designing, fabricating, characterizing, and utilizing edible nanoparticles from a variety of different food-grade ingredients. © 2015 Institute of Food Technologists®

  12. The application of Markov decision process in restaurant delivery robot

    Science.gov (United States)

    Wang, Yong; Hu, Zhen; Wang, Ying

    2017-05-01

    As the restaurant delivery robot is often in a dynamic and complex environment, including the chairs inadvertently moved to the channel and customers coming and going. The traditional path planning algorithm is not very ideal. To solve this problem, this paper proposes the Markov dynamic state immediate reward (MDR) path planning algorithm according to the traditional Markov decision process. First of all, it uses MDR to plan a global path, then navigates along this path. When the sensor detects there is no obstructions in front state, increase its immediate state reward value; when the sensor detects there is an obstacle in front, plan a global path that can avoid obstacle with the current position as the new starting point and reduce its state immediate reward value. This continues until the target is reached. When the robot learns for a period of time, it can avoid those places where obstacles are often present when planning the path. By analyzing the simulation experiment, the algorithm has achieved good results in the global path planning under the dynamic environment.

  13. Molecular Design of Bioinspired Nanostructures for Biomedical Applications: Synthesis, Self-Assembly and Functional Properties

    Science.gov (United States)

    Xu, Hesheng Victor; Zheng, Xin Ting; Mok, Beverly Yin Leng; Ibrahim, Salwa Ali; Yu, Yong; Tan, Yen Nee

    2016-08-01

    Biomolecules are the nanoscale building blocks of cells, which play multifaceted roles in the critical biological processes such as biomineralization in a living organism. In these processes, the biological molecules such as protein and nucleic acids use their exclusive biorecognition properties enabled from their unique chemical composition, shape and function to initiate a cascade of cellular events. The exceptional features of these biomolecules, coupled with the recent advancement in nanotechnology, have led to the emergence of a new research field that focuses on the molecular design of bioinspired nanostructures that inherit the extraordinary function of natural biomaterials. These “bioinspired” nanostructures could be formulated by biomimetic approaches through either self-assembling of biomolecules or acting as a biomolecular template/precursor to direct the synthesis of nanocomposite. In either situation, the resulting nanomaterials exhibit phenomenal biocompatibility, superb aqueous solubility and excellent colloidal stability, branding them exceptionally desirable for both in vitro and in vivo biomedical applications. In this review, we will present the recent developments in the preparation of “bioinspired” nanostructures through biomimetic self-assembly and biotemplating synthesis, as well as highlight their functional properties and potential applications in biomedical diagnostics and therapeutic delivery. Lastly, we will conclude this topic with some personal perspective on the challenges and future outlooks of the “bioinspired” nanostructures for nanomedicine.

  14. Barriers to Liposomal Gene Delivery: from Application Site to the Target.

    Science.gov (United States)

    Saffari, Mostafa; Moghimi, Hamid Reza; Dass, Crispin R

    2016-01-01

    Gene therapy is a therapeutic approach to deliver genetic material into cells to alter their function in entire organism. One promising form of gene delivery system (DDS) is liposomes. The success of liposome-mediated gene delivery is a multifactorial issue and well-designed liposomal systems might lead to optimized gene transfection particularly in vivo. Liposomal gene delivery systems face different barriers from their site of application to their target, which is inside the cells. These barriers include presystemic obstacles (epithelial barriers), systemic barriers in blood circulation and cellular barriers. Epithelial barriers differ depending on the route of administration. Systemic barriers include enzymatic degradation, binding and opsonisation. Both of these barriers can act as limiting hurdles that genetic material and their vector should overcome before reaching the cells. Finally liposomes should overcome cellular barriers that include cell entrance, endosomal escape and nuclear uptake. These barriers and their impact on liposomal gene delivery will be discussed in this review.

  15. Donor-Acceptor Block Copolymers: Synthesis and Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Kazuhiro Nakabayashi

    2014-04-01

    Full Text Available Fullerene derivatives have been widely used for conventional acceptor materials in organic photovoltaics (OPVs because of their high electron mobility. However, there are also considerable drawbacks for use in OPVs, such as negligible light absorption in the visible-near-IR regions, less compatibility with donor polymeric materials and high cost for synthesis and purification. Therefore, the investigation of non-fullerene acceptor materials that can potentially replace fullerene derivatives in OPVs is increasingly necessary, which gives rise to the possibility of fabricating all-polymer (polymer/polymer solar cells that can deliver higher performance and that are potentially cheaper than fullerene-based OPVs. Recently, considerable attention has been paid to donor-acceptor (D-A block copolymers, because of their promising applications as fullerene alternative materials in all-polymer solar cells. However, the synthesis of D-A block copolymers is still a challenge, and therefore, the establishment of an efficient synthetic method is now essential. This review highlights the recent advances in D-A block copolymers synthesis and their applications in all-polymer solar cells.

  16. Electrochemically Active Biofilms Assisted Nanomaterial Synthesis for Environmental Applications

    KAUST Repository

    Ahmed, Elaf

    2017-12-01

    Nanomaterials have a great potential for environmental applications due to their high surface areas and high reactivity. This dissertation investigated the use of electrochemically active biofilms (EABs) as a synthesis approach for the fabrication and environmental applications of different nanomaterials. Bacteria in EABs generate electrons upon consuming electron donor and have the ability to transport these electrons to solid or insoluble substrates through extracellular electron transport (EET) mechanism. The extracellularly transported electrons, once utilized, can lead to nanoparticle synthesis. In this dissertation, noble metal (i.e., Au, Pd, and Pt) ultra-small nanoparticles (USNPs) were first synthesized with the assistance by the EABs. The assynthesized USNPs had a size range between 2 and 7 nm and exhibited excellent catalytic performance in dye decomposition. Also in this research, a two-dimensional (2D) cobalt nanosheet was successfully synthesized in the presence of EABs. A simple biogenic route led to the transformation of cobalt acetate to produce a green, toxic free homogeneous 2D cobalt nanosheet structure. Further, TiO2 nanotubes were successfully combined with the noble metal USNPs to enhance their photocatalytic activity. In this work, for the first time, the noble metal USNPs were directly reduced and decorated on the internal surfaces of the TiO2 nanotubes structure assisted by the EABs. The USNPs modified TiO2 nanotubes generated significantly improved photoelectrocatatlyic performances. This dissertation shines lights on the use of EABs in ultra-small nanoparticle synthesis.

  17. Engineering and Applications of fungal laccases for organic synthesis

    Directory of Open Access Journals (Sweden)

    Ballesteros Antonio

    2008-11-01

    Full Text Available Abstract Laccases are multi-copper containing oxidases (EC 1.10.3.2, widely distributed in fungi, higher plants and bacteria. Laccase catalyses the oxidation of phenols, polyphenols and anilines by one-electron abstraction, with the concomitant reduction of oxygen to water in a four-electron transfer process. In the presence of small redox mediators, laccase offers a broader repertory of oxidations including non-phenolic substrates. Hence, fungal laccases are considered as ideal green catalysts of great biotechnological impact due to their few requirements (they only require air, and they produce water as the only by-product and their broad substrate specificity, including direct bioelectrocatalysis. Thus, laccases and/or laccase-mediator systems find potential applications in bioremediation, paper pulp bleaching, finishing of textiles, bio-fuel cells and more. Significantly, laccases can be used in organic synthesis, as they can perform exquisite transformations ranging from the oxidation of functional groups to the heteromolecular coupling for production of new antibiotics derivatives, or the catalysis of key steps in the synthesis of complex natural products. In this review, the application of fungal laccases and their engineering by rational design and directed evolution for organic synthesis purposes are discussed.

  18. Synthesis and Characterization of Stimuli Responsive Block Copolymers, Self-Assembly Behavior and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Determan, Michael Duane [Iowa State Univ., Ames, IA (United States)

    2005-12-17

    The central theme of this thesis work is to develop new block copolymer materials for biomedical applications. While there are many reports of stimuli-responsive amphiphilic [19-21] and crosslinked hydrogel materials [22], the development of an in situ gel forming, pH responsive pentablock copolymer is a novel contribution to the field, Figure 1.1 is a sketch of an ABCBA pentablock copolymer. The A blocks are cationic tertiary amine methacrylates blocked to a central Pluronic F127 triblock copolymer. In addition to the prerequisite synthetic and macromolecular characterization of these new materials, the self-assembled supramolecular structures formed by the pentablock were experimentally evaluated. This synthesis and characterization process serves to elucidate the important structure property relationships of these novel materials, The pH and temperature responsive behavior of the pentablock copolymer were explored especially with consideration towards injectable drug delivery applications. Future synthesis work will focus on enhancing and tuning the cell specific targeting of DNA/pentablock copolymer polyplexes. The specific goals of this research are: (1) Develop a synthetic route for gel forming pentablock block copolymers with pH and temperature sensitive properties. Synthesis of these novel copolymers is accomplished with ATRP, yielding low polydispersity and control of the block copolymer architecture. Well defined macromolecular characteristics are required to tailor the phase behavior of these materials. (2) Characterize relationship between the size and shape of pentablock copolymer micelles and gel structure and the pH and temperature of the copolymer solutions with SAXS, SANS and CryoTEM. (3) Evaluate the temperature and pH induced phase separation and macroscopic self-assembly phenomenon of the pentablock copolymer. (4) Utilize the knowledge gained from first three goals to design and formulate drug delivery formulations based on the multi

  19. Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

    Directory of Open Access Journals (Sweden)

    Satoru Mori

    2017-10-01

    Full Text Available Phthalocyanines and subphthalocyanines are attracting attention as functional dyes that are applicable to organic solar cells, photodynamic therapy, organic electronic devices, and other applications. However, phthalocyanines are generally difficult to handle due to their strong ability to aggregate, so this property must be controlled for further applications of phthalocyanines. On the other hand, trifluoroethoxy-substituted phthalocyanines are known to suppress aggregation due to repulsion of the trifluoroethoxy group. Furthermore, the electronic characteristics of phthalocyanines are significantly changed by the strong electronegativity of fluorine. Therefore, it is expected that trifluoroethoxy-substituted phthalocyanines can be applied to new industrial fields. This review summarizes the synthesis and application of trifluoroethoxy-substituted phthalocyanine and subphthalocyanine derivatives.

  20. Application of ionizing radiation for metal nanoclusters synthesis

    International Nuclear Information System (INIS)

    Smietanko-Chmielewska, D.K.; Chmielewski, A.G.; Warsaw University of Technology, Warsaw

    2011-01-01

    Complete text of publication follows. Possibility of ionizing radiation application in nanotechnology has been observed from very beginning when this field of science and technology was named. The lithography is based on electron and ion beam applications, and metal clusters synthesis by radiation induced radicals was reported many years ago. International Atomic Energy Agency was the first organization which has started coordinated programs on radiation applications in nanotechnology which are being continued in the frame of regional cooperation project RER8014. Some of applications led to patented technical solutions. Then review papers and chapters in the books have been published. The main applications beside of lithography deal with metal nanoclusters and nano-composites synthesis. Polymer composites containing metal nanoparticles have attracted a great interest due to their unique chemical and physical properties. 'Green' chemistry promotes application of natural fibers in such structures, among them cellulose is one of the most frequently used. However, cellulose fabric have ability to absorb moisture, so under certain conditions of humidity and temperature they can be subjected to microbial attack. One of the most popular and best known antibacterial agents is silver, which serves as a potential antibacterial material acting against an exceptionally broad spectrum of bacteria including activity against antibiotic-resistant bacteria. Silver nanoparticles (Ag NPs) were grown at the cellulose fibers surface by direct reduction of AgNO 3 with electron beam (EB) application. The big field of development concerns nano composites, possibility of e/X units application enlarge this possibility to industrial scale product manufacturing. Acknowledgement: This work was supported by the IAEA, regional project RER/8/014 and by the Ministry of Science and Higher Education, project DPN/W14/IAEA/2009.

  1. Specific synthesis of Pt nanowires for catalytic applications

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, Daniela; Kehres, Jan; Al-Shamery, Katharina [IRAC, University Oldenburg (Germany); Center of Interface Science, CIS (Germany); Borchert, Holger; Kolny-Olesiak, Joanna [EHF, University Oldenburg (Germany); Center of Interface Science, CIS (Germany); Baeumer, Marcus [IAPC, University Bremen (Germany); Center of Interface Science, CIS (Germany)

    2008-07-01

    Metallic nanomaterials are of great interest in the last years due to their interesting properties as new materials for optical, electronic, magnetic or catalytic applications. Particularly size and morphology of such nanoparticulate systems offer also high potential for material improvement. A promising issue is the preparation of platinum nanowires by means of colloidal chemistry which allows obtaining particles with well-defined size and shape by use of stabilizing ligands. Recent efforts have been focused on the development of synthesis to obtain these nanowires. Therefore we were able to prepare dodecylamine-capped Pt nanowires with 2 nm in diameter and several multiple in length in varying the synthesis conditions. The influence of temperature, stabilisers and reducing agents on the morphology has been investigated. The catalytic activity of such nanowires immobilized at different oxidic supports could also be demonstrated on the example of CO oxidation and are compared to spherical Pt and bimetallic colloidal nanoparticles.

  2. Synthesis and catalytic applications of combined zeolitic/mesoporous materials

    Directory of Open Access Journals (Sweden)

    Jarian Vernimmen

    2011-11-01

    Full Text Available In the last decade, research concerning nanoporous siliceous materials has been focused on mesoporous materials with intrinsic zeolitic features. These materials are thought to be superior, because they are able to combine (i the enhanced diffusion and accessibility for larger molecules and viscous fluids typical of mesoporous materials with (ii the remarkable stability, catalytic activity and selectivity of zeolites. This review gives an overview of the state of the art concerning combined zeolitic/mesoporous materials. Focus is put on the synthesis and the applications of the combined zeolitic/mesoporous materials. The different synthesis approaches and formation mechanisms leading to these materials are comprehensively discussed and compared. Moreover, Ti-containing nanoporous materials as redox catalysts are discussed to illustrate a potential implementation of combined zeolitic/mesoporous materials.

  3. Performance Testing of Data Delivery Techniques for AJAX Applications

    NARCIS (Netherlands)

    Bozdag, E.; Mesbah, A.; Van Deursen, A.

    2008-01-01

    Preprint of paper published in: Journal of Web Engineering (Rinton Press), 8 (4), 2009 AJAX applications are designed to have high user interactivity and low user-perceived latency. Real-time dynamic web data such as news headlines, stock tickers, and auction updates need to be propagated to the

  4. Synthesis and characterization of modified starch/polybutadiene as novel transdermal drug delivery system.

    Science.gov (United States)

    Saboktakin, Mohammad Reza; Akhyari, Shahab; Nasirov, Fizuli A

    2014-08-01

    Transdermal drug delivery systems are topically administered medicaments in the form of patches that deliver drugs for systemic effects at a predetermined and controlled rate. It works very simply in which drug is applied inside the patch and it is worn on skin for long period of time. Polymer matrix, drug, permeation enhancers are the main components of transdermal drug delivery systems. The objective of the present study was to develop the modified starch and 1,4-cis polybutadiene nanoparticles as novel polymer matrix system. We have been studied the properties of a novel transdermal drug delivery system with clonidine as drug model. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Synthesis and Characterization of Salicylate-zinc Layered Hydroxide Nano hybrid for Antiinflammatory Active Delivery

    International Nuclear Information System (INIS)

    Mohd Zobir Hussein; Mohd Zobir Hussein; Munirah Ramli; Khatijah Yusoff

    2011-01-01

    The emergence of nano technology has prompted much advancement in various areas of research that includes cellular delivery systems, particularly those dealing with delivery of compounds with therapeutic effects. This study aimed at investigating the use of a layered nano material for formation of a new organic-inorganic nano hybrid material. In this work, a compound of zinc layered hydroxide (ZLH) used as a host for a guest, anti-inflammatory agent salicylate (SA) was synthesized. Through simple, direct reaction of SA solution at various concentrations with commercial zinc oxide, SA was found to be intercalated between the ZLH inorganic layers. Powder x-ray diffraction (PXRD) patterns revealed that the basal spacing of the nano hybrid is around 16.14 Angstrom. Further characterizations also confirmed that SA was successfully intercalated into the interlayers of the nano hybrid. Results generated from this work provide information beneficial for development of a new delivery system for therapeutic compounds consisting of antiinflammatory agents. (author)

  6. Electrosprayed nanoparticles for drug delivery and pharmaceutical applications

    Science.gov (United States)

    Sridhar, Radhakrishnan; Ramakrishna, Seeram

    2013-01-01

    Nanotechnology based Pharma has emerged significantly and has influenced the Pharma industry up to a considerable extent. Nanoparticles technology holds a good share of the nanotech Pharma and is significant in comparison with the other domains. Electrospraying technology answers the potential needs of nanoparticle production such as scalability, reproducibility, effective encapsulation etc. Many drugs have been electrosprayed with and without polymer carriers. Drug release characteristics are improved with the incorporation of biodegradable polymer carriers which sustain the release of encapsulated drug. Electrospraying is acknowledged as an important technique for the preparation of nanoparticles with respect to pharmaceutical applications. Herein we attempted to consolidate the reports pertaining to electrospraying and their corresponding therapeutic application area. PMID:23512013

  7. Theranostic applications of carbon nanomaterials in cancer: Focus on imaging and cargo delivery.

    Science.gov (United States)

    Chen, Daiqin; Dougherty, Casey A; Zhu, Kaicheng; Hong, Hao

    2015-07-28

    Carbon based nanomaterials have attracted significant attention over the past decades due to their unique physical properties, versatile functionalization chemistry, and biological compatibility. In this review, we will summarize the current state-of-the-art applications of carbon nanomaterials in cancer imaging and drug delivery/therapy. The carbon nanomaterials will be categorized into fullerenes, nanotubes, nanohorns, nanodiamonds, nanodots and graphene derivatives based on their morphologies. The chemical conjugation/functionalization strategies of each category will be introduced before focusing on their applications in cancer imaging (fluorescence/bioluminescence, magnetic resonance (MR), positron emission tomography (PET), single-photon emission computed tomography (SPECT), photoacoustic, Raman imaging, etc.) and cargo (chemo/gene/therapy) delivery. The advantages and limitations of each category and the potential clinical utilization of these carbon nanomaterials will be discussed. Multifunctional carbon nanoplatforms have the potential to serve as optimal candidates for image-guided delivery vectors for cancer. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Silica hollow core microstructured fibers for beam delivery in industrial and medical applications

    Directory of Open Access Journals (Sweden)

    Jonathan Dale Shephard

    2015-04-01

    Full Text Available The focus of this review is our recent work to develop microstructured hollow core fibers for two applications where the flexible delivery of a single mode beam is desired. Also, a review of other fiber based solutions is included.High power, short-pulsed lasers are widely used for micro-machining, providing high precision and high quality. However, the lack of truly flexible beam delivery systems limits their application to the processing of relatively small planar components. To address this, we developed hollow-core optical fibers for the 1 μm and green wavelength ranges. The hollow core overcomes the power delivery limitations of conventional silica fibers arising from nonlinear effects and material damage in the solid core. We have characterized such fibers in terms of power handling capability, damage threshold, bend loss and dispersion, and practically demonstrated delivery of high peak power pulses from the nanosecond to the femtosecond regime. Such fibers are ideal candidates for industrial laser machining applications.In laser surgical applications, meanwhile, an Er:YAG laser (2.94 μm is frequently the laser of choice because the water contained in tissue strongly absorbs this wavelength. If this laser beam is precisely delivered damage to surrounding tissue can be minimized. A common delivery method of surgical lasers, for use in the operating theatre, is articulated arms that are bulky, cumbersome and unsuitable for endoscopic procedures. To address this need for flexible mid-IR delivery we developed silica based hollow core fibers. By minimizing the overlap of the light with glass it is possible to overcome the material absorption limits of silica and achieve low attenuation. Additionally, it is possible to deliver pulse energies suitable for the ablation of both hard and soft tissue even with very small bend radii. The flexibility and small physical size of systems based on these fibers will enable new minimally invasive surgical

  9. Biobased functional polyesters for coating applications: Synthesis, characterization and application

    NARCIS (Netherlands)

    Noordover, B.A.J.; Duchateau, R.; Koning, C.E.; Benthem, van R.A.T.M.; Ming, W.; Haveren, van J.; Es, van D.S.

    2007-01-01

    Thermosetting coating systems contain polyesters as binders. A crucial property of these polymers is their functionality. During coating application, the polyesters are cross-linked in situ, which means that each polymer chain needs a sufficient no. of reactive end-groups. Renewable monomers are

  10. Nanotechnology in Drug Delivery and Tissue Engineering: From Discovery to Applications

    OpenAIRE

    Shi, Jinjun; Votruba, Alexander R.; Farokhzad, Omid C.; Langer, Robert

    2010-01-01

    The application of nanotechnology in medicine, referred to as nanomedicine, is offering numerous exciting possibilities in healthcare. Herein, we discuss two important aspects of nanomedicine—drug delivery and tissue engineering—highlighting the advances we have recently experienced, the challenges we are currently facing, and what we are likely to witness in the near future.

  11. An Overview of Chitosan Nanoparticles and Its Application in Non-Parenteral Drug Delivery

    Directory of Open Access Journals (Sweden)

    Munawar A. Mohammed

    2017-11-01

    Full Text Available The focus of this review is to provide an overview of the chitosan based nanoparticles for various non-parenteral applications and also to put a spotlight on current research including sustained release and mucoadhesive chitosan dosage forms. Chitosan is a biodegradable, biocompatible polymer regarded as safe for human dietary use and approved for wound dressing applications. Chitosan has been used as a carrier in polymeric nanoparticles for drug delivery through various routes of administration. Chitosan has chemical functional groups that can be modified to achieve specific goals, making it a polymer with a tremendous range of potential applications. Nanoparticles (NP prepared with chitosan and chitosan derivatives typically possess a positive surface charge and mucoadhesive properties such that can adhere to mucus membranes and release the drug payload in a sustained release manner. Chitosan-based NP have various applications in non-parenteral drug delivery for the treatment of cancer, gastrointestinal diseases, pulmonary diseases, drug delivery to the brain and ocular infections which will be exemplified in this review. Chitosan shows low toxicity both in vitro and some in vivo models. This review explores recent research on chitosan based NP for non-parenteral drug delivery, chitosan properties, modification, toxicity, pharmacokinetics and preclinical studies.

  12. Nanotechnology in Drug Delivery and Tissue Engineering: From Discovery to Applications

    Science.gov (United States)

    Shi, Jinjun; Votruba, Alexander R.; Farokhzad, Omid C.; Langer, Robert

    2010-01-01

    The application of nanotechnology in medicine, referred to as nanomedicine, is offering numerous exciting possibilities in healthcare. Herein, we discuss two important aspects of nanomedicine—drug delivery and tissue engineering—highlighting the advances we have recently experienced, the challenges we are currently facing, and what we are likely to witness in the near future. PMID:20726522

  13. Nanotechnology in drug delivery and tissue engineering: from discovery to applications.

    Science.gov (United States)

    Shi, Jinjun; Votruba, Alexander R; Farokhzad, Omid C; Langer, Robert

    2010-09-08

    The application of nanotechnology in medicine, referred to as nanomedicine, is offering numerous exciting possibilities in healthcare. Herein, we discuss two important aspects of nanomedicine, drug delivery and tissue engineering, highlighting the advances we have recently experienced, the challenges we are currently facing, and what we are likely to witness in the near future.

  14. Medical applications of membranes: Drug delivery, artificial organs and tissue engineering

    NARCIS (Netherlands)

    Stamatialis, Dimitrios; Papenburg, B.J.; Girones nogue, Miriam; Saiful, S.; Bettahalli Narasimha, M.S.; Schmitmeier, Stephanie; Wessling, Matthias

    2008-01-01

    This paper covers the main medical applications of artificial membranes. Specific attention is given to drug delivery systems, artificial organs and tissue engineering which seem to dominate the interest of the membrane community this period. In all cases, the materials, methods and the current

  15. Supporting Pervasive Computing Applications with Active Context Fusion and Semantic Context Delivery

    DEFF Research Database (Denmark)

    Roy, Nirmalya; Gu, Tao; Das, Sajal

    2010-01-01

    Future pervasive computing applications are envisioned to adapt the applications’ behaviors by utilizing various contexts of an environment and its users. Such context information may often be ambiguous and also heterogeneous, which make the delivery of unambiguous context information to real app...

  16. Metal–organic framework membranes: from synthesis to separation application

    KAUST Repository

    Qiu, Shilun

    2014-06-26

    Metal-organic framework (MOF) materials, which are constructed from metal ions or metal ion clusters and bridging organic linkers, exhibit regular crystalline lattices with relatively well-defined pore structures and interesting properties. As a new class of porous solid materials, MOFs are attractive for a variety of industrial applications including separation membranes-a rapidly developing research area. Many reports have discussed the synthesis and applications of MOFs and MOF thin films, but relatively few have addressed MOF membranes. This critical review provides an overview of the diverse MOF membranes that have been prepared, beginning with a brief introduction to the current techniques for the fabrication of MOF membranes. Gas and liquid separation applications with different MOF membranes are also included (175 references). This journal is © the Partner Organisations 2014.

  17. Synthesis, Properties and Potential Applications of Porous Graphene: A Review

    Institute of Scientific and Technical Information of China (English)

    Paola Russo; Anming Hu; Giuseppe Compagnini

    2013-01-01

    Since the discovery of graphene, many efforts have been done to modify the graphene structure for integrating this novel material to nanoelectronics, fuel cells, energy storage devices and in many other applications. This leads to the production of different types of graphene-based materials, which possess properties different from those of pure graphene. Porous graphene is an example of this type of materials. It can be considered as a graphene sheet with some holes/pores within the atomic plane. Due to its spongy structure, porous graphene can have potential applications as membranes for molecular sieving, energy storage components and in nanoelectronics. In this review, we present the recent progress in the synthesis of porous graphene. The properties and the potential applications of this new material are also discussed.

  18. Radiation synthesis and modification of polymers for biomedical applications. Final results of a co-ordinated research project. 1996-2000

    CERN Document Server

    2002-01-01

    Radiation techniques are being used for synthesis of hydrogels, functional polymers, interpenetrating systems, chemical modification of surfaces, immobilization of bioactive materials, synthesis of functional micro- and nanospheres and processing of naturally derived biomaterials. Potential medical applications of these biomaterials include implants, topical dressings, treatment devices and drug delivery systems. Biotechnological applications include diagnostic assays, separation and purification systems, immobilized enzyme and cell bioprocesses and cell culture surfaces. The main objective of the CRP on The use of Radiation Processing to Prepare Biomaterials for Application in Medicine was to co-ordinate the research carried out in the participating countries, to ensure that different research programmes complement each other and the information exchange is available to all. Furthermore, the objective was to expand the use of ionizing radiation in two major areas: synthesis of polymers and gels for medical a...

  19. Synthesis of Polymer-Lipid Nanoparticles for Image-Guided Delivery of Dual Modality Therapy

    NARCIS (Netherlands)

    Mieszawska, Aneta J.; Kim, Yongtae; Gianella, Anita; van Rooy, Inge; Priem, Bram; Labarre, Matthew P.; Ozcan, Canturk; Cormode, David P.; Petrov, Artiom; Langer, Robert; Farokhzad, Omid C.; Fayad, Zahi A.; Mulder, Willem J. M.

    2013-01-01

    For advanced treatment of diseases such as cancer, multicomponent, multifunctional nanoparticles hold great promise. In the current study we report the synthesis of a complex nanoparticle (NP) system with dual drug loading as well as diagnostic properties. To that aim we present a methodology where

  20. Self-regulating insulin delivery systems I. Synthesis and characterization of glycosylated insulin

    NARCIS (Netherlands)

    Jeong, Seo Young; Kim, Sung Wan; Eenink, Martinus J.D.; Feijen, Jan

    1984-01-01

    A design for a self-regulating insulin delivery system based on the competitive binding of glucose and glycosylated insulin to the lectin Concanavalin A is proposed. A differnt approach to diabetes therapy is the attempt to effect a permanent cure of the disease by supplementing the patient's

  1. Recent Advances in the Application of Vitamin E TPGS for Drug Delivery

    Science.gov (United States)

    Yang, Conglian; Wu, Tingting; Qi, Yan; Zhang, Zhiping

    2018-01-01

    D-ɑ-tocopheryl polyethylene glycol succinate (Vitamin E TPGS or TPGS) has been approved by FDA as a safe adjuvant and widely used in drug delivery systems. The biological and physicochemical properties of TPGS provide multiple advantages for its applications in drug delivery like high biocompatibility, enhancement of drug solubility, improvement of drug permeation and selective antitumor activity. Notably, TPGS can inhibit the activity of ATP dependent P-glycoprotein and act as a potent excipient for overcoming multi-drug resistance (MDR) in tumor. In this review, we aim to discuss the recent advances of TPGS in drug delivery including TPGS based prodrugs, nitric oxide donor and polymers, and unmodified TPGS based formulations. These potential applications are focused on enhancing delivery efficiency as well as the therapeutic effect of agents, especially on overcoming MDR of tumors. It also demonstrates that the clinical translation of TPGS based nanomedicines is still faced with many challenges, which requires more detailed study on TPGS properties and based delivery system in the future. PMID:29290821

  2. Porous Zinc Oxide Thin Films: Synthesis Approaches and Applications

    Directory of Open Access Journals (Sweden)

    Marco Laurenti

    2018-02-01

    Full Text Available Zinc oxide (ZnO thin films have been widely investigated due to their multifunctional properties, i.e., catalytic, semiconducting and optical. They have found practical use in a wide number of application fields. However, the presence of a compact micro/nanostructure has often limited the resulting material properties. Moreover, with the advent of low-dimensional ZnO nanostructures featuring unique physical and chemical properties, the interest in studying ZnO thin films diminished more and more. Therefore, the possibility to combine at the same time the advantages of thin-film based synthesis technologies together with a high surface area and a porous structure might represent a powerful solution to prepare ZnO thin films with unprecedented physical and chemical characteristics that may find use in novel application fields. Within this scope, this review offers an overview on the most successful synthesis methods that are able to produce ZnO thin films with both framework and textural porosities. Moreover, we discuss the related applications, mainly focused on photocatalytic degradation of dyes, gas sensor fabrication and photoanodes for dye-sensitized solar cells.

  3. Synthesis optimization of calcium aluminate cement phases for biomedical applications

    International Nuclear Information System (INIS)

    Andrade, T.L.; Santos, G.L.; Oliveira, I.R.; Pandolfelli, V.C.

    2011-01-01

    Calcium aluminate cement (CAC) has been studied as a potential material for applications in the areas of health such as, endodontics and bone reconstruction. These studies have been based on commercial products consisting of a mixture of phases. Improvements can be attained by investigating the synthesis routes of CAC aiming the proper balance between the phases and the control of impurities that may impair its performance for biomedical applications. Thus, the aim of this work was to study the CAC synthesis routes in the Al 2 O 3 -CaCO 3 and Al 2 O 3 -CaO systems, as well as the phase characterization attained by means of X ray analysis. The Al 2 O 3 -CaO route enabled the production of the target phases (CA, CA 2 , C 3 A and C 12 A 7 ) with a higher purity compared to the Al2O3-CaCO3 one. As a result the particular properties of these phases can be evaluated to define a more suitable composition that results in better properties for an endodontic cement and other applications. (author)

  4. Metal Oxide Nano structures: Synthesis, Properties, and Applications

    International Nuclear Information System (INIS)

    Xu, L. H.; Patil, D. S.; Yang, J.; Xiao, J.

    2015-01-01

    In recent years, nano structured materials have attracted wide attention due to their fascinating optical and electrical properties, which make these materials potentially suitable for applications in electronics, optics, photonics, and sensors. Some metal oxides show a wide variety of morphologies such as nano wires, nano rods, nano tubes, nano rings, and nano belts. Synthesis and investigation of these metal-oxide nano structures are beneficial not only for understanding the fundamental phenomena in low dimensional systems, but also for developing new-generation nano devices with high performance.

  5. Cell-free protein synthesis: applications in proteomics and biotechnology.

    Science.gov (United States)

    He, Mingyue

    2008-01-01

    Protein production is one of the key steps in biotechnology and functional proteomics. Expression of proteins in heterologous hosts (such as in E. coli) is generally lengthy and costly. Cell-free protein synthesis is thus emerging as an attractive alternative. In addition to the simplicity and speed for protein production, cell-free expression allows generation of functional proteins that are difficult to produce by in vivo systems. Recent exploitation of cell-free systems enables novel development of technologies for rapid discovery of proteins with desirable properties from very large libraries. This article reviews the recent development in cell-free systems and their application in the large scale protein analysis.

  6. Design, Microfabrication and Characterization of a Power Delivery System for new Biomedical Applications

    Directory of Open Access Journals (Sweden)

    CARUSO Massimo

    2017-05-01

    Full Text Available This paper presents the design, microfabrication and characterization of a wireless power delivery system capable of driving a surface acoustic wave sensor (SAW for biomedical applications. The system consists of two planar, spiral-square microcoils, which have been geometrically optimized in order to maximize the quality factor Q. The integration of the SAW - microcoil system into artificial implant sites will allow a real-time biofilm growth monitoring and treatment, providing countless advantages to the related medical applications.

  7. Synthesis of mesoporous SiO2–ZnO nanocapsules: encapsulation of small biomolecules for drugs and “SiOZO-plex” for gene delivery

    International Nuclear Information System (INIS)

    Kumar, Vijay Bhooshan; Annamanedi, Madhavi; Prashad, Muvva Durga; Arunasree, Kalle M.; Mastai, Yitzhak; Gedanken, Aharon; Paik, Pradip

    2013-01-01

    This work presents a new synthesis of mesoporous SiO 2 –ZnO composite nanocapsules with sizes of 90–150 nm and represents their applications in encapsulation of small biomolecules (fluorescent molecules, drugs, and DNA) for uses in medical biotechnology (e.g., drug and gene delivery) for the first time. The nanocapsule size and morphology have been confirmed through the HRSEM and HRTEM. The mesoporous structure of the novel materials has been confirmed through both BET and HRTEM, and the pore diameter observed to be ca. 2–8 nm with an average diameter of 5.1 nm. The BET surface area of mesoporous SiO 2 –ZnO was found to be ∼230 m 2 g −1 . Three different types of pores were detected through HRTEM: type-I, normal pores in silica matrix, pore with ZnO nanoparticles at the boundary (type-II) and type-III, the pores with tiny ZnO nanoparticles (∼5–7 nm) inside them. To demonstrate the biocompatibility and cell viability of the nanocapsules, normal and cancerous lymphocyte cells have been chosen and investigated in a systematic way. Fluorescent dye (Rhodamine 6G), anticancer drug e.g., Doxorubicin (DOX) were loaded in all types of pores, and EtBr-labeled DNA molecules were loaded efficiently into the mesopores of second and third types of the composite nanocapsules to manifest the characteristic of mesoporous, and to find out its loading efficacy. The release kinetics of Rhodamine 6G and DOX were studied. The results highlight the potential of novel functional mesoporous SiO 2 –ZnO nanoparticles for using as the carrier of drugs and formation of “SiOZO-plex”, a complex of mesoporous SiO 2 –ZnO with DNA for gene delivery applications.Graphical Abstract

  8. Synthesis of mesoporous SiO{sub 2}-ZnO nanocapsules: encapsulation of small biomolecules for drugs and 'SiOZO-plex' for gene delivery

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Vijay Bhooshan [School of Engineering Sciences and Technology, University of Hyderabad (India); Annamanedi, Madhavi [School of Life Sciences, University of Hyderabad, Department of Animal Sciences (India); Prashad, Muvva Durga [University of Hyderabad, Centre for Nanoscience and Nanotechnology (India); Arunasree, Kalle M. [School of Life Sciences, University of Hyderabad, Department of Animal Sciences (India); Mastai, Yitzhak; Gedanken, Aharon, E-mail: gedanken@mail.biu.ac.il [Bar-Ilan University, Department of Chemistry, Institute for Nanotechnology and Advanced Materials (Israel); Paik, Pradip, E-mail: ppse@uohyd.ernet.in [School of Engineering Sciences and Technology, University of Hyderabad (India)

    2013-09-15

    This work presents a new synthesis of mesoporous SiO{sub 2}-ZnO composite nanocapsules with sizes of 90-150 nm and represents their applications in encapsulation of small biomolecules (fluorescent molecules, drugs, and DNA) for uses in medical biotechnology (e.g., drug and gene delivery) for the first time. The nanocapsule size and morphology have been confirmed through the HRSEM and HRTEM. The mesoporous structure of the novel materials has been confirmed through both BET and HRTEM, and the pore diameter observed to be ca. 2-8 nm with an average diameter of 5.1 nm. The BET surface area of mesoporous SiO{sub 2}-ZnO was found to be {approx}230 m{sup 2} g{sup -1}. Three different types of pores were detected through HRTEM: type-I, normal pores in silica matrix, pore with ZnO nanoparticles at the boundary (type-II) and type-III, the pores with tiny ZnO nanoparticles ({approx}5-7 nm) inside them. To demonstrate the biocompatibility and cell viability of the nanocapsules, normal and cancerous lymphocyte cells have been chosen and investigated in a systematic way. Fluorescent dye (Rhodamine 6G), anticancer drug e.g., Doxorubicin (DOX) were loaded in all types of pores, and EtBr-labeled DNA molecules were loaded efficiently into the mesopores of second and third types of the composite nanocapsules to manifest the characteristic of mesoporous, and to find out its loading efficacy. The release kinetics of Rhodamine 6G and DOX were studied. The results highlight the potential of novel functional mesoporous SiO{sub 2}-ZnO nanoparticles for using as the carrier of drugs and formation of 'SiOZO-plex', a complex of mesoporous SiO{sub 2}-ZnO with DNA for gene delivery applications.Graphical Abstract.

  9. Materials Research Society Symposium Proceedings Volume 635. Anisotropic Nanoparticles - Synthesis, Characterization and Applications

    National Research Council Canada - National Science Library

    Lyon, L

    2000-01-01

    This volume contains a series of papers originally presented at Symposium C, "Anisotropic Nanoparticles Synthesis, Characterization and Applications," at the 2000 MRS Fall Meeting in Boston, Massachusetts...

  10. Synthesis of Biomaterials for use in Drug Delivery to the Brain

    DEFF Research Database (Denmark)

    Bak, Martin

    -subtype of the immune system. Hence, this methodology could potentially offer a tool to specifically stimulate and activate differentiation of cell-subtypes of the immune system, making it a viable platform for e.g. cancer vaccines. In conclusion, during this PhD we have managed to develop multiple strategies......The need for new treatments of brain diseases is growing with the increasing lifespan of western populations. Drug delivery to the central nervous system (CNS) is generally perceived as a tremendous challenge. Drug transport across the brain endothelium forming the blood-brain barrier (BBB....... The objective of this PhD thesis was to expand the knowledge about nanoparticle delivery to the brain, by developing targeted hard and soft nanoparticles that could be sensitized towards glioma pathological conditions. The first study attempted to improve the understanding of TfR-mediated transcytosis...

  11. Design and Synthesis of Self-Assembled Polymeric Nanoparticles for Cancer Drug Delivery

    Science.gov (United States)

    Logie, Jennifer

    Current chemotherapeutics are plagued by poor solubility and selectivity, requiring toxic excipients in formulations and causing a number of dose limiting side effects. Nanoparticle delivery has emerged as a strategy to more effectively deliver chemotherapeutics to the tumour site. Specifically, polymeric micelles enable the solubilization of hydrophobic small molecule drugs within the core and mitigate the necessity of excipients. Notwithstanding the significant progress made in polymeric micelle delivery, translation is limited by poor stability and low drug loading. In this work, a rational design approach is used to chemically modify poly(D,L-lactide-co-2-methyl-2-carboxytrimethylene carbonate)-graft-poly(ethylene glycol) (P(LA-co-TMCC)-g-PEG) in order to overcome these limitations and effectively deliver drug to tumours. The PEG density of the polymer system was optimized to enhance the stability of our polymeric micelles. Higher PEG densities permitted the lyophilization of micelles and enhanced the serum stability of the system. To increase the drug loading of our system, we facilitated specific intermolecular interactions within the micelle core. For drugs that form colloidal aggregates, such as pentyl-PABC doxazolidine, polymers were used to stabilize the colloidal core against aggregation and protein adsorption. For more challenging molecules, where self-assembly cannot be controlled, such as docetaxel, we modified the polymeric backbone with a peptide from the binding site of the drug to achieve loadings five times higher than those achieved in conventional micelle systems. This novel docetaxel nanoparticle was assessed in vivo in an orthotopic mouse model of breast cancer, where it showed a wider therapeutic index than the conventional ethanolic polysorbate 80 formulation. The improved tolerability of this formulation enabled higher dosing regimens and led to heightened efficacy and survival in this mouse model. Combined, these studies validated P

  12. Toward Developing Made-to-Order Metal-Organic Frameworks: Design, Synthesis and Applications

    KAUST Repository

    Ashri, Lubna Y.

    2016-05-26

    Synthesis of materials with certain properties for targeted applications is an ongoing challenge in materials science. One of the most interesting classes of solid-state materials that have been recently introduced with the potential to address this is metal-organic frameworks (MOFs). MOFs chemistry offers a higher degree of control over materials to be synthesized utilizing various new design strategies, such as the molecular building blocks (MBBs) and the supermolecular building layers (SBLs) approaches. Depending on using predetermined building blocks, these strategies permit the synthesis of MOFs with targeted topologies and enable fine tuning of their properties. This study examines a number of aspects of the design and synthesis of MOFs while exploring their possible utilization in two diverse fields related to energy and pharmaceutical applications. Concerning MOFs design and synthesis, the work presented here explores the rational design of various MOFs with predicted topologies and tunable cavities constructed by pillaring pre-targeted 2-periodic SBLs using the ligand-to-axial and six-connected axial-to-axial pillaring strategies. The effect of expanding the confined spaces in prepared MOFs or modifying their functionalities, while preserving the underlying network topology, was investigated. Additionally, The MBBs approach was employed to discover new modular polynuclear rare earth (RE)-MBBs in the presence of different angular polytopic ligands containing carboxylate and nitrogen moieties with the aid of a modulator. The goal was to assess the diverse possible coordination modes and construct highly-connected nets for utility in the design of new MOFs and enhance the predictability of structural outcomes. The effect of adjusting ligands’ length-to-width ratio on the prepared MOFs was also evaluated. As a result, the reaction conditions amenable for reliable formation of the unprecedented octadecanuclear, octanuclear and double tetranuclear RE-MBBs were

  13. Enhanced Transdermal Delivery by Combined Application of Dissolving Microneedle Patch on Serum-Treated Skin.

    Science.gov (United States)

    Kim, Suyong; Dangol, Manita; Kang, Geonwoo; Lahiji, Shayan F; Yang, Huisuk; Jang, Mingyu; Ma, Yonghao; Li, Chengguo; Lee, Sang Gon; Kim, Chang Hyun; Choi, Young Wook; Kim, So Jeong; Ryu, Ja Hyun; Baek, Ji Hwoon; Koh, Jaesuk; Jung, Hyungil

    2017-06-05

    Dissolving microneedle (DMN), a transdermal drug delivery system in which drugs are encapsulated in a biodegradable polymeric microstructure, is designed to dissolve after skin penetration and release the encapsulated drugs into the body. However, because of limited loading capacity of drugs within microsized structures, only a small dosage can be delivered, which is often insufficient for patients. We propose a novel DMN application that combines topical and DMN application simultaneously to improve skin permeation efficiency. Drugs in pretreated topical formulation and encapsulated drugs in DMN patch are delivered into the skin through microchannels created by DMN application, thus greatly increasing the delivered dose. We used 4-n-butylresorcinol to treat human hyperpigmentation and found that sequential application of serum formulation and DMNs was successful. In skin distribution experiments using Alexa Fluor 488 and 568 dyes as model drugs, we confirmed that the pretreated serum formulation was delivered into the skin through microchannels created by the DMNs. In vitro skin permeation and retention experiments confirmed that this novel combined application delivered more 4-n-butylresorcinol into the skin than traditional DMN-only and serum-only applications. Moreover, this combined application showed a higher efficacy in reducing patients' melanin index and hyperpigmented regions compared with the serum-only application. As combined application of DMNs on serum-treated skin can overcome both dose limitations and safety concerns, this novel approach can advance developments in transdermal drug delivery.

  14. Photopatternable Magnetic Hollowbots by Nd-Fe-B Nanocomposite for Potential Targeted Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Hui Li

    2018-04-01

    Full Text Available In contrast to traditional drug administration, targeted drug delivery can prolong, localize, target and have a protected drug interaction with the diseased tissue. Drug delivery carriers, such as polymeric micelles, liposomes, dendrimers, nanotubes, and so on, are hard to scale-up, costly, and have short shelf life. Here we show the novel fabrication and characterization of photopatternable magnetic hollow microrobots that can potentially be utilized in microfluidics and drug delivery applications. These magnetic hollowbots can be fabricated using standard ultraviolet (UV lithography with low cost and easily accessible equipment, which results in them being easy to scale up, and inexpensive to fabricate. Contact-free actuation of freestanding magnetic hollowbots were demonstrated by using an applied 900 G external magnetic field to achieve the movement control in an aqueous environment. According to the movement clip, the average speed of the magnetic hollowbots was estimated to be 1.9 mm/s.

  15. Thermocleavable pi-Conjugated polymers. Synthesis and photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Helgesen, M

    2009-10-15

    Polymer solar cells (plastic solar cells) have seen remarkable improvements in recent years where power conversion efficiencies of up to 6% have been reported for small area devices. However in terms of stability polymer solar cells degrade during illumination and in the dark leading to operational lifetimes that are generally very poor. There has been a recent interest in the operational stability of devices and more importantly on the understanding of why devices and materials break down. This has lead to the discovery of a new class of materials that enable exceptionally long device lifetimes (>20000 hours). This Ph.D. thesis describes the synthesis, characterization and photovoltaic applications of these novel polymer materials. A key feature of these materials is that solubilizing thermocleavable alkyl ester side chains are introduced on the polymer backbone. The side chains make the polymer soluble in organic solvents and allow film formation via solution processing. Subsequently they can be removed by heating in a post-processing step forming a harder insoluble material with enhanced stability. These new thermocleavable materials can potentially offer higher chromophore density, higher level processing and improved stability in a solar cell device. Methods are developed for the incorporation of alkoxy chains and thermocleavable ester groups on the benzothiadiazole and the thiophene units in an attempt to evolve the PDTBT system to a more advanced level. The synthesis and photovoltaic applications of the PDTTP and PDTBT systems is described. (author)

  16. Soft chemical synthesis of silicon nanosheets and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Hideyuki; Ikuno, Takashi [Toyota Central R& D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

    2016-12-15

    Two-dimensional silicon nanomaterials are expected to show different properties from those of bulk silicon materials by virtue of surface functionalization and quantum size effects. Since facile fabrication processes of large area silicon nanosheets (SiNSs) are required for practical applications, a development of soft chemical synthesis route without using conventional vacuum processes is a challenging issue. We have recently succeeded to prepare SiNSs with sub-nanometer thicknesses by exfoliating layered silicon compounds, and they are found to be composed of crystalline single-atom-thick silicon layers. In this review, we present the synthesis and modification methods of SiNSs. These SiNSs have atomically flat and smooth surfaces due to dense coverage of organic moieties, and they are easily self-assembled in a concentrated state to form a regularly stacked structure. We have also characterized the electron transport properties and the electronic structures of SiNSs. Finally, the potential applications of these SiNSs and organic modified SiNSs are also reviewed.

  17. Nano crystals-Related Synthesis, Assembly, and Energy Applications 2012

    International Nuclear Information System (INIS)

    Zou, B.; Yu, W.W.; Seo, J.; Zhu, T.; Hu, M.Z.

    2012-01-01

    During the past decades, nano crystals have attracted broad attention due to their unique shape- and size-dependent physical and chemical properties that differ drastically from their bulk counterparts. Hitherto, much effort has been dedicated to achieving rational controlling over the morphology, assembly, and related energy applications of the nano materials. Therefore, the ability to manipulate the morphology, size, and size distribution of inorganic nano materials is still an important goal in modern materials physics and chemistry. Especially, the world's demand for energy supply is causing a dramatic escalation of social and political unrest. Likewise, the environmental impact of the global climate change due to the combustion of fossil fuel is becoming increasingly alarming. These problems compel us to search for effective routes to build devices that can supply sustainable energy, with not only high efficiency but also environmental friendship. One of ways to relieve the energy crisis is to exploit devices based on renewable energy sources, such as solar energy and water power. Aiming at this exploration, the primary stage requires the design of appropriate strategies for the synthesis of high-quality nano crystals with respect to size uniformity and superior electrochemical performances. As a consequence, we organize the current special issue for Journal of Nano materials to provide the authors with a platform and readers with the latest achievements of nano crystals-related synthesis, assembly, and energy applications.

  18. Nano crystals-Related Synthesis, Assembly, and Energy Applications

    International Nuclear Information System (INIS)

    Dai, Q.; Hu, M.Z.; Yu, B.Z.; William, W.; Seo, J.

    2011-01-01

    Fundamental material properties have been dramatically altered in the nano scale regime because of quantum confinement effect. The unique size-tunable functionalities of nano materials make them involved in an extensive variety of energy applications, such as light-emitting diodes and solar cells. These applications have been demonstrated to cut energy consumption. In response to the ever-growing energy demands as well as the concerns of global warming, researchers are actively placing their enormous emphasis on the exploration of energy savings. During this exploration, the primary stage requires the design of appropriate strategies for the synthesis of high-quality nano crystals in terms of size uniformity and superior optical/electronic properties. Especially, there is a need to seek green-chemistry approaches for the synthesis of environmentally benign and user-friendly nano crystals. Another recent area of focus is the use of individual nano crystals as building blocks for self-assembly, providing new opportunities to improve the nano crystal performance

  19. Synthesis, Optical Properties and Applications for New Trianguleniums Derivatives

    DEFF Research Database (Denmark)

    Santella, Marco

    The development of new types of emissive organic dyes is an exciting area of research due to the applicability of these compounds in a wide range of disciplines. Cationic triangulenium salts are highly stable carbenium ions with a planar conformation. The convenient and versatile synthetic proced...... focused on the synthesis of thioether para substituted dyes, where the reactivity of various para-methoxy substituted propeller shaped cations towards different alkyl thiols was examined. Furthermore, ringclosure reactions of these thioether bearing propellers in order to obtain trioxa...... structures. These dyes possess excellent emissive properties with possible applications as cell staining agents or as fluorescent probes. Lastly, I focused on the use of triangulenes as binding group for molecular electronics. It has been shown that TATA can form self-assembled monolayers (SAMs) on a gold...

  20. Synthesis of Disintegrable Metal Composite for Oilfield Applications

    Science.gov (United States)

    Zhang, Zhihui; Salinas, Bobby; Newman, Caleb; Xu, Zhiyue

    Lightweight metal composites were traditionally developed for weight-critical applications. Recently, significant efforts have been made to improve the corrosion performance. In this study we report the synthesis of a novel type of high-strength metal composites with enhanced corrosion rate for use in self-disintegratable tools in oil and gas wells. The composites were fabricated through a powder metallurgy procedure by consolidating reactive metal powders that were coated with nanoscale metallic and/or ceramic coatings. The interaction between the metal matrix and coating was studied using X-ray diffraction, differential scanning calorimetry, and electron microscopy. The composites exhibit simultaneous high strength (up to 460 MPa) and two orders of magnitude increase in the corrosion rate (i.e., 250 mg/cm2/hr) under saline water. The corrosion behavior and associated field applications are described.

  1. Carbon nanotubes: properties, synthesis, purification, and medical applications

    Science.gov (United States)

    2014-01-01

    Current discoveries of different forms of carbon nanostructures have motivated research on their applications in various fields. They hold promise for applications in medicine, gene, and drug delivery areas. Many different production methods for carbon nanotubes (CNTs) have been introduced; functionalization, filling, doping, and chemical modification have been achieved, and characterization, separation, and manipulation of individual CNTs are now possible. Parameters such as structure, surface area, surface charge, size distribution, surface chemistry, and agglomeration state as well as purity of the samples have considerable impact on the reactivity of carbon nanotubes. Otherwise, the strength and flexibility of carbon nanotubes make them of potential use in controlling other nanoscale structures, which suggests they will have a significant role in nanotechnology engineering. PMID:25170330

  2. Carbon nanotubes: properties, synthesis, purification, and medical applications

    Science.gov (United States)

    Eatemadi, Ali; Daraee, Hadis; Karimkhanloo, Hamzeh; Kouhi, Mohammad; Zarghami, Nosratollah; Akbarzadeh, Abolfazl; Abasi, Mozhgan; Hanifehpour, Younes; Joo, Sang Woo

    2014-08-01

    Current discoveries of different forms of carbon nanostructures have motivated research on their applications in various fields. They hold promise for applications in medicine, gene, and drug delivery areas. Many different production methods for carbon nanotubes (CNTs) have been introduced; functionalization, filling, doping, and chemical modification have been achieved, and characterization, separation, and manipulation of individual CNTs are now possible. Parameters such as structure, surface area, surface charge, size distribution, surface chemistry, and agglomeration state as well as purity of the samples have considerable impact on the reactivity of carbon nanotubes. Otherwise, the strength and flexibility of carbon nanotubes make them of potential use in controlling other nanoscale structures, which suggests they will have a significant role in nanotechnology engineering.

  3. Drug Delivery and Cosmeceutical Applications of Poly- Lactic Acid Based Novel Constructs - A Review.

    Science.gov (United States)

    Ruiz-Ruiz, Federico; Mancera-Andrade, Elena Ivonne; Parra-Saldivar, Roberto; Keshavarz, Tajalli; Iqbal, Hafiz M N

    2017-01-01

    Poly (lactic acid) (PLA) based novel constructs have been engineered for targeted applications in various biomedical sectors of the modern world. In this context, a special focus has been given to pharmaceutical and cosmeceutical industries. In this review, we extensively reviewed, analyzed and compiled salient information from the authentic bibliographic sources including PubMed, Scopus, Elsevier, Springer, Bentham Science and other scientific databases. A focused review question and inclusion/exclusion criterion were adopted to appraise the quality of retrieved peer-reviewed research literature. Recently, bio-based constructs are being engineered for target applications in different bio- and non-bio sectors of the modern world to address the growing human health-related serious concerns. The utilization of properly designed and structured materials thus allows the creation of a well-defined environment that induces a series of directed measures, and so on. Over the last few years, PLA-based novel constructs have received exceptional attention as potential candidates for various biotechnological and biomedical applications at large and drug delivery in particular. Owing to their unique characteristics including biocompatibility, together with the adjustable thermomechanical and tunable control drug release, PLA has raised interesting applications in many sectors of the medical world. So far, many of such PLA-based bio-constructs have been exploited in drug delivery systems, cosmeceutical products, and therapeutic uses. In recent years, many new applications have been reported for PLA-based materials at the micro- and nano- level, resulting in novel requests for specific drug delivery and cosmeceutical sectors. In summary, this review summarizes recent research on different aspects of PLA and PLA-based novel constructs and their potential biomedical applications. Moreover, with the aid of nanotechnology, PLA has made a positive impact in emerging sectors such as

  4. Radiation Synthesis of Some Copolymers and their Potential Industrial Applications

    International Nuclear Information System (INIS)

    Hegazy, N.R.

    2015-01-01

    The field of biomaterials has advanced rapidly in the recent years. Much attention has been focused on the research and developments of polymer for biomedical applications. One of the most promising classes of materials for biomedical applications seems to be the hydrogels. In this connection, the first part concern with preparation of various types of hydrogels by using gamma irradiation for possible Industrial uses. Novel super absorbent hydrogels were prepared successfully from carboxymethylcellulose sodium (CMC) and acrylamide (AAm) due to their good biocompatibility. The structure of the hydrogels was characterized by FT-IR and thermogravimetric analysis. Scanning electron microscopy was also carried out to study the surface morphology of the hydrogel and it verifies that the synthesized hydrogels have a porous structure then the synthesis of silver (AAm/CMC) nano composite hydrogel from the prepared (AAm/CMC) hydrogel has done and characterized using UV-visible, XRD, EDX, SEM and TEM which confirmed the formation of silver nanoparticles and determined its particle size. Their equilibrium swelling ratio in distilled water and different physiological fluids were evaluated. Moreover, the hydrogels exhibited smart swelling and shrinking in different aqueous solutions that could be controlled by changing CMC content. The second part concern with the synthesis of grafting polymers using γ-rays and the factors affect on the grafting process onto LDPE, HDPE and PP films by binary comonomer GMA:NVIm such as solvent, concentration, composition and dose were investigated. The grafted films were characterized by enough number of techniques. Afterwards, the grafted films were treated by many chemical reagents such as Isonicotinamide, 4(6) Aminouracil, Sulpha methoxy di azine and Guanidine hydrochloride at different interval times, respectively. The prepared hydrogels are promising for the applications in the biomaterials area and the applicability of grafted films to be

  5. Self-Assembled Nanocarriers Based on Amphiphilic Natural Polymers for Anti- Cancer Drug Delivery Applications.

    Science.gov (United States)

    Sabra, Sally; Abdelmoneem, Mona; Abdelwakil, Mahmoud; Mabrouk, Moustafa Taha; Anwar, Doaa; Mohamed, Rania; Khattab, Sherine; Bekhit, Adnan; Elkhodairy, Kadria; Freag, May; Elzoghby, Ahmed

    2017-01-01

    Micellization provides numerous merits for the delivery of water insoluble anti-cancer therapeutic agents including a nanosized 'core-shell' drug delivery system. Recently, hydrophobically-modified polysaccharides and proteins are attracting much attention as micelle forming polymers to entrap poorly soluble anti-cancer drugs. By virtue of their small size, the self-assembled micelles can passively target tumor tissues via enhanced permeation and retention effect (EPR). Moreover, the amphiphilic micelles can be exploited for active-targeted drug delivery by attaching specific targeting ligands to the outer micellar hydrophilic surface. Here, we review the conjugation techniques, drug loading methods, physicochemical characteristics of the most important amphiphilic polysaccharides and proteins used as anti-cancer drug delivery systems. Attention focuses on the mechanisms of tumor-targeting and enhanced anti-tumor efficacy of the encapsulated drugs. This review will highlight the remarkable advances of hydrophobized polysaccharide and protein micelles and their potential applications as anti-cancer drug delivery nanosystems. Micellar nanocarriers fabricated from amphiphilic natural polymers hold great promise as vehicles for anti-cancer drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  6. Design, development and characterization of multi-functionalized gold nanoparticles for biodetection and targeted boron delivery in BNCT applications

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Subhra [Department of Tumor Immunology, Radboud University Nijmegen Medical Centre (Netherlands); Bakeine, Gerald J., E-mail: Jamesbakeine1@yahoo.com [Department of Internal Medicine and Therapeutics-Section of Clinical Toxicology, University of Pavia, Piazza Botta 10, 27100 Pavia (Italy); Krol, Silke [Institute of Neurology, Fondazione IRCCS Carlo Besta, Milan (Italy); Ferrari, Cinzia; Clerici, Anna M.; Zonta, Cecilia; Cansolino, Laura [Department of Surgery, Laboratory of Experimental Surgery, University of Pavia (Italy); Ballarini, Francesca [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Bortolussi, Silva [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)] [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy); Stella, Subrina; Protti, Nicoletta [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Bruschi, Piero [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy); Altieri, Saverio [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)] [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy)

    2011-12-15

    The aim of this study is to optimize targeted boron delivery to cancer cells and its tracking down to the cellular level. To this end, we describe the design and synthesis of novel nanovectors that double as targeted boron delivery agents and fluorescent imaging probes. Gold nanoparticles were coated with multilayers of polyelectrolytes functionalized with the fluorescent dye (FITC), boronophenylalanine and folic acid. In vitro confocal fluorescence microscopy demonstrated significant uptake of the nanoparticles in cancer cells that are known to overexpress folate receptors. - Highlights: Black-Right-Pointing-Pointer Synthesis of multi-labeled gold nanoparticles for selective boron delivery to tumor cells. Black-Right-Pointing-Pointer Tumor selectivity is achieved through folic acid receptor targeting. Black-Right-Pointing-Pointer Optical fluorescent microscopy allows tracking of cellular uptake of the gold nanoparticle. Black-Right-Pointing-Pointer In vitro tests demonstrate selective nanoparticle up in folate receptor positive tumor cells.

  7. Polysaccharide-Based Materials Associated with or Coordinated to Gold Nanoparticles: Synthesis and Medical Application.

    Science.gov (United States)

    Facchi, Débora P; da Cruz, Joziel A; Bonafé, Elton G; Pereira, Antonio G B; Fajardo, André R; Venter, Sandro A S; Monteiro, Johny P; Muniz, Edvani C; Martins, Alessandro F

    2017-01-01

    Gold nanoparticles (AuNPs) have enormous potential for application in imaging, diagnosis, and therapies in the medical field. AuNPs are renowned for their localized surface plasmon resonance (LSPR) properties, large surface area, and biocompatibility with body fluids. Further, AuNPs have featured prominently in new methodologies for cancer treatments, like photothermal and imaging therapies. Although AuNPs present enormous potential for application in the medical field, their instability under physiological conditions prevents further uses. However, this limitation may be overcome by associating AuNPs with biopolymers. To the best of our knowledge, a revision paper rationalizing the structure/property relationship and applications of AuNPspolysaccharide composites in the medical field has not been published yet. This manuscript discusses the most relevant aspects and state-of-art concepts surrounding the synthesis of AuNPs based on green chemistry and their association with polysaccharides that can efficiently function both as stabilizing and reducing agents of Au nanoparticles. Even more, polysaccharide devices may inhibit non-specific interactions between AuNPs and biological macromolecules, suppressing unsuitable "protein corona" formations on AuNP surfaces, thereby increasing the potential of AuNP composites of being employing as drug delivery matrices and wound-healing devices as well as in photothermal/ imaging purposes for cancer treatments and biosensors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Nanodiamonds as novel nanomaterials for biomedical applications: drug delivery and imaging systems.

    Science.gov (United States)

    Kaur, Randeep; Badea, Ildiko

    2013-01-01

    Detonation nanodiamonds (NDs) are emerging as delivery vehicles for small chemical drugs and macromolecular biotechnology products due to their primary particle size of 4 to 5 nm, stable inert core, reactive surface, and ability to form hydrogels. Nanoprobe technology capitalizes on the intrinsic fluorescence, high refractive index, and unique Raman signal of the NDs, rendering them attractive for in vitro and in vivo imaging applications. This review provides a brief introduction of the various types of NDs and describes the development of procedures that have led to stable single-digit-sized ND dispersions, a crucial feature for drug delivery systems and nanoprobes. Various approaches used for functionalizing the surface of NDs are highlighted, along with a discussion of their biocompatibility status. The utilization of NDs to provide sustained release and improve the dispersion of hydrophobic molecules, of which chemotherapeutic drugs are the most investigated, is described. The prospects of improving the intracellular delivery of nucleic acids by using NDs as a platform are exemplified. The photoluminescent and optical scattering properties of NDs, together with their applications in cellular labeling, are also reviewed. Considering the progress that has been made in understanding the properties of NDs, they can be envisioned as highly efficient drug delivery and imaging biomaterials for use in animals and humans.

  9. Nanodiamonds as novel nanomaterials for biomedical applications: drug delivery and imaging systems

    Directory of Open Access Journals (Sweden)

    Kaur R

    2013-01-01

    Full Text Available Randeep Kaur, Ildiko BadeaDrug Design and Discovery Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, CanadaAbstract: Detonation nanodiamonds (NDs are emerging as delivery vehicles for small chemical drugs and macromolecular biotechnology products due to their primary particle size of 4 to 5 nm, stable inert core, reactive surface, and ability to form hydrogels. Nanoprobe technology capitalizes on the intrinsic fluorescence, high refractive index, and unique Raman signal of the NDs, rendering them attractive for in vitro and in vivo imaging applications. This review provides a brief introduction of the various types of NDs and describes the development of procedures that have led to stable single-digit-sized ND dispersions, a crucial feature for drug delivery systems and nanoprobes. Various approaches used for functionalizing the surface of NDs are highlighted, along with a discussion of their biocompatibility status. The utilization of NDs to provide sustained release and improve the dispersion of hydrophobic molecules, of which chemotherapeutic drugs are the most investigated, is described. The prospects of improving the intracellular delivery of nucleic acids by using NDs as a platform are exemplified. The photoluminescent and optical scattering properties of NDs, together with their applications in cellular labeling, are also reviewed. Considering the progress that has been made in understanding the properties of NDs, they can be envisioned as highly efficient drug delivery and imaging biomaterials for use in animals and humans.Keywords: dispersion, surface functionalization, toxicity, carriers, fluorescence, light scattering

  10. Seaweed Polysaccharide-Based Nanoparticles: Preparation and Applications for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Jayachandran Venkatesan

    2016-01-01

    Full Text Available In recent years, there have been major advances and increasing amounts of research on the utilization of natural polymeric materials as drug delivery vehicles due to their biocompatibility and biodegradability. Seaweed polysaccharides are abundant resources and have been extensively studied for several biological, biomedical, and functional food applications. The exploration of seaweed polysaccharides for drug delivery applications is still in its infancy. Alginate, carrageenan, fucoidan, ulvan, and laminarin are polysaccharides commonly isolated from seaweed. These natural polymers can be converted into nanoparticles (NPs by different types of methods, such as ionic gelation, emulsion, and polyelectrolyte complexing. Ionic gelation and polyelectrolyte complexing are commonly employed by adding cationic molecules to these anionic polymers to produce NPs of a desired shape, size, and charge. In the present review, we have discussed the preparation of seaweed polysaccharide-based NPs using different types of methods as well as their usage as carriers for the delivery of various therapeutic molecules (e.g., proteins, peptides, anti-cancer drugs, and antibiotics. Seaweed polysaccharide-based NPs exhibit suitable particle size, high drug encapsulation, and sustained drug release with high biocompatibility, thereby demonstrating their high potential for safe and efficient drug delivery.

  11. Structural and biological properties of thermosensitive chitosan-graphene hybrid hydrogels for sustained drug delivery applications.

    Science.gov (United States)

    Saeednia, Leyla; Yao, Li; Berndt, Marcus; Cluff, Kim; Asmatulu, Ramazan

    2017-09-01

    Chitosan has the ability to make injectable thermosensitive hydrogels which has been highly investigated for drug delivery applications. The addition of nanoparticles is one way to increase the mechanical strength of thermosensitive chitosan hydrogel and subsequently and control the burst release of drug. Graphene nanoparticles have shown unique mechanical, optical and electrical properties which can be exploited for biomedical applications, especially in drug delivery. This study, have focused on the mechanical properties of a thermosensitive and injectable hybrid chitosan hydrogel incorporated with graphene nanoparticles. Scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray diffraction (XRD) have been used for morphological and chemical characterization of graphene infused chitosan hydrogels. The cell viability and cytotoxicity of graphene-contained hydrogels were analyzed using the alamarBlue ® technique. In-vitro methotrexate (MTX) release was investigated from MTX-loaded hybrid hydrogels as well. As a last step, to evaluate their efficiency as a cancer treatment delivery system, an in vitro anti-tumor test was also carried out using MCF-7 breast cancer cell lines. Results confirmed that a thermosensitive chitosan-graphene hybrid hydrogel can be used as a potential breast cancer therapy system for controlled delivery of methotrexate. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2381-2390, 2017. © 2017 Wiley Periodicals, Inc.

  12. Porous silicon-cyclodextrin based polymer composites for drug delivery applications.

    Science.gov (United States)

    Hernandez-Montelongo, J; Naveas, N; Degoutin, S; Tabary, N; Chai, F; Spampinato, V; Ceccone, G; Rossi, F; Torres-Costa, V; Manso-Silvan, M; Martel, B

    2014-09-22

    One of the main applications of porous silicon (PSi) in biomedicine is drug release, either as a single material or as a part of a composite. PSi composites are attractive candidates for drug delivery systems because they can display new chemical and physical characteristics, which are not exhibited by the individual constituents alone. Since cyclodextrin-based polymers have been proven efficient materials for drug delivery, in this work β-cyclodextrin-citric acid in-situ polymerization was used to functionalize two kinds of PSi (nanoporous and macroporous). The synthesized composites were characterized by microscopy techniques (SEM and AFM), physicochemical methods (ATR-FTIR, XPS, water contact angle, TGA and TBO titration) and a preliminary biological assay was performed. Both systems were tested as drug delivery platforms with two different model drugs, namely, ciprofloxacin (an antibiotic) and prednisolone (an anti-inflammatory), in two different media: pure water and PBS solution. Results show that both kinds of PSi/β-cyclodextrin-citric acid polymer composites, nano- and macro-, provide enhanced release control for drug delivery applications than non-functionalized PSi samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Synthesis of polymer-lipid nanoparticles for image-guided delivery of dual modality therapy.

    Science.gov (United States)

    Mieszawska, Aneta J; Kim, YongTae; Gianella, Anita; van Rooy, Inge; Priem, Bram; Labarre, Matthew P; Ozcan, Canturk; Cormode, David P; Petrov, Artiom; Langer, Robert; Farokhzad, Omid C; Fayad, Zahi A; Mulder, Willem J M

    2013-09-18

    For advanced treatment of diseases such as cancer, multicomponent, multifunctional nanoparticles hold great promise. In the current study we report the synthesis of a complex nanoparticle (NP) system with dual drug loading as well as diagnostic properties. To that aim we present a methodology where chemically modified poly(lactic-co-glycolic) acid (PLGA) polymer is formulated into a polymer-lipid NP that contains a cytotoxic drug doxorubicin (DOX) in the polymeric core and an anti-angiogenic drug sorafenib (SRF) in the lipidic corona. The NP core also contains gold nanocrystals (AuNCs) for imaging purposes and cyclodextrin molecules to maximize the DOX encapsulation in the NP core. In addition, a near-infrared (NIR) Cy7 dye was incorporated in the coating. To fabricate the NP we used a microfluidics-based technique that offers unique NP synthesis conditions, which allowed for encapsulation and fine-tuning of optimal ratios of all the NP components. NP phantoms could be visualized with computed tomography (CT) and near-infrared (NIR) fluorescence imaging. We observed timed release of the encapsulated drugs, with fast release of the corona drug SRF and delayed release of a core drug DOX. In tumor bearing mice intravenously administered NPs were found to accumulate at the tumor site by fluorescence imaging.

  14. Novel flurbiprofen derivatives with improved brain delivery: synthesis, in vitro and in vivo evaluations.

    Science.gov (United States)

    Zheng, Dan; Shuai, Xiao; Li, Yanping; Zhou, Peng; Gong, Tao; Sun, Xun; Zhang, Zhirong

    2016-09-01

    Tarenflurbil (R-flurbiprofen) was acknowledged as a promising candidate in Alzheimer's disease (AD) therapy. However, the Phase III study of tarenflurbil was extremely restricted by its poor delivery efficiency to the brain. To tackle this problem, the novel carriers for tarenflurbil, racemic flurbiprofen (FLU) derivatives (FLU-D1 and FLU-D2) modified by N,N-dimethylethanolamine-related structures were synthesized and characterized. These derivatives showed good safety level in vitro and they possessed much higher cellular uptake efficiency in brain endothelial cells than FLU did. More importantly, the uptake experiments suggested that they were internalized via active transport mechanisms. Biodistribution studies in rats also illustrated a remarkably enhanced accumulation of these derivatives in the brain. FLU-D2, the ester linkage form of these derivatives, achieved a higher brain-targeting efficiency. Its C max and AUC 0- t were enhanced by 12.09-fold and 4.61-fold, respectively compared with those of FLU. Additionally, it could be hydrolyzed by esterase in the brain to release the parent FLU, which might facilitate its therapeutic effect. These in vitro and in vivo results highlighted the improvement of the brain-targeted delivery of FLU by making use of N,N-dimethylethanolamine ligand, with which an active transport mechanism was involved.

  15. Surfactant-assisted sol–gel synthesis of forsterite nanoparticles as a novel drug delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Hassanzadeh-Tabrizi, S.A., E-mail: tabrizi1980@gmail.com [Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Bigham, Ashkan [Advanced Materials Research Center, Materials Engineering Department, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Rafienia, Mohammad [Biosensor Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of)

    2016-01-01

    In the present study, forsterite nanoparticles were synthesized via surfactant-assisted sol–gel method using cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The effects of CTAB contents and heat treatment on the textural properties and drug release from nanoparticles were investigated. The synthesized powders were studied by X-ray diffraction, Fourier transform infrared spectra, Brunauer–Emmett–Teller surface area analysis and transmission electron microscope images. Mg{sub 2}SiO{sub 4} materials demonstrated mesoporous characteristics and large specific surface area ranging from 159 to 30 m{sup 2}/g. The TEM results showed that forsterite nanorods had diameters about 4 nm and lengths ranging from 10 to 60 nm. It was found that the samples with 6 g CTAB show slower drug release rate than the other specimens, which is due to smaller pore size. This study revealed that the drug delivery of forsterite can be tailored by changing the amount of surfactant. - Highlights: • Forsterite nanoparticles were synthesized via surfactant-assisted sol–gel method. • Nanoparticles were loaded with ibuprofen as a novel drug delivery system. • Synthesized nanoparticles had a rod-like morphology. • CTAB concentration strongly affected the textural properties and drug release of the nanoparticles.

  16. Synthesis of New Functionalized Citric Acid-based Dendrimers as Nanocarrier Agents for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Sanaz Motamedi

    2011-06-01

    Full Text Available Introduction: Citric acid-polyethylene glycol-citric acid (CPEGC triblock dendrimers can serve as potential delivery systems. Methods: In this investigation, CPEGC triblock dendrimers were synthesized and then imidazole groups were conjugated onto the surface of the G1, G2 and G3 of the obtained dendrimers. In order to study the type of the interactions between the functionalized dendrimers and a drug molecule, Naproxen which contains acidic groups, was examined as a hydrophobic drug in which the interactions would be of the electrostatic kind between its acidic groups and the lone pair electrons of nitrogen atom in imidazole groups. The quantity of the trapped drug and also the amount of its release were measured with UV spectrometric method in pH 1, 7.4 and 10. The average diameter of the nanocarriers was measured by Dynamic Light Scattering (DLS technique Results: The size range of particles was determined to be 16-50 nm for different generations. The rate of the release increased in pH=10 in all generations due to the increase in Naproxen solubility and the hydrolysis of the esteric bonds in the mentioned pH. The results showed that the amount of the trapped drug increased with the increase in the generation of the dendrimer and pH. Conclusion: Based on our findings, we suggest CPEGC triblock dendrimers possess great potential to be used as drug/gene delivery system.

  17. Synthesis and investigation of novel shelf-stable, brain-specific chemical delivery system

    International Nuclear Information System (INIS)

    Al-Obaid, Abdulrahman M.; Farag, Hassan A.; Khalil, Ashraf A.; Hamide, Sami G. Abdel; Ahmed, Hassan S.; Al-Affifi, Ahmed M.; Gadkariem Elrasheed, A.; El-Subbagh, Hussein I.; Al-Shabanah, Othman A.; El-Kashef, Hassan A.

    2006-01-01

    A 1, 4-dihydropyridine pyridinium salt type redox system is described as a general and flexible method for site-specific and sustained delivery of drugs into the brain. Monoamine oxidase inhibitors (MAOIs) were used as a model example to be delivered into the brain. Chemical and biological oxidations of these compounds were investigated. The prepared 1, 4-dihydropyridines were subjected to various chemical and biological oxidations to evaluate their ability to cross blood brain barrier (BBB), and to be oxidized biologically into their corresponding quaternary compounds. 1-(Ethioxy-carbonylmethyl)-3, 5-bis[N-(2-fluoro-benzylideneamino)carbamoyl]-1, 4-dyhydropyridine (31) proved to cross BBB in adequate rate and converted by the oxidizing enzymes into the corresponding quaternary salt N-(ethoxycarbolynmethyl)-3, 5-bis[N-(2-fluorobenylideneamino)carbamoyl]pyridimium bromide(20). Stability studies of the synthesized chemical delivery systems (CDSs) at various pH values and temperatures showed the shelf life time of a solution containing compound 31 is 20.53 days at 5C, which recommended a lower storage temperature for such solutions. The prepared CDSs proved to be fairly stable for powder form storage. The stability of the prepared compounds is attributed to the conjugation of the two carboxylic functions at C3 and C5 of the pyridine ring with their adjacent double bonds. These results are in consistency with the original rationale design. (author)

  18. New biodegradable dextran-based hydrogels for protein delivery: Synthesis and characterization.

    Science.gov (United States)

    Pacelli, Settimio; Paolicelli, Patrizia; Casadei, Maria Antonietta

    2015-08-01

    A new derivative of dextran grafted with polyethylene glycol methacrylate through a carbonate bond (DEX-PEG-MA) has been synthesized and characterized. The photo-crosslinking reaction of DEX-PEG-MA allowed the obtainment of biodegradable networks tested for their mechanical and release properties. The new hydrogels were compared with those made of dextran methacrylate (DEX-MA), often employed as drug delivery systems of small molecules. The inclusion of PEG as a spacer created additional interactions among the polymeric chains improving the extreme fragility and lack of hardness typical of gels made of DEX-MA. Moreover, the different behavior in terms of swelling and degradability of the networks was able to affect the release of a model macromolecule over time, making DEX-PEG-MA matrices suitable candidates for the delivery of high molecular weight peptides. Interestingly, the combination of the two dextran derivatives showed intermediate ability to modulate the release of high molecular weight macromolecules. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Synthesis and applications of {sup 13}C glycerol

    Energy Technology Data Exchange (ETDEWEB)

    Stocking, E.; Khalsa, O.; Martinez, R.A.; Silks, L.A. III [Los Alamos National Laboratory, NM (United States)

    1994-12-01

    Due in part to the use of labeled glycerol for the {sup 13}C enrichment of biomolecules, we are currently developing new synthetic routes to various isotopomers of glycerol. Judging from our experience, traditional methods of glycerol synthesis are not easily adapted for isotopic enrichment and/or have poor overall yields (12 to 15%). Furthermore, the use of glycerol for enrichment can be prohibitively expensive and its availability is limited by the level of demand. We are presently developing a short de novo synthesis of glycerol from carbon dioxide ({approximately}53% overall yield for four steps) and are examining the feasibility of synthesizing site-specific {sup 13}C-labeled glycerol and dihydroxyacetone (DHA) from labeled methanol and carbon dioxide. One application of {sup 13}C glycerol we have examined is enzymatic conversion of glycerol to glyceraldehyde-3-monophosphate or dihydroxyacetone monophosphate (DHAP) with yields ranging from 25 to 50% (as determined by NMR spectroscopy). We are also pursuing the chemical conversion of {sup 13}C-labeled DHA to DHAP. We are especially interested in {sup 13}C-labeled DHAP because we are investigating its use as a chemo-enzymatic precursor for both labeled 2-deoxyribose and 2-deoxyribonucleic acids.

  20. Construction and characterization of a pure protein hydrogel for drug delivery application.

    Science.gov (United States)

    Xu, Xu; Xu, ZhaoKang; Yang, XiaoFeng; He, YanHao; Lin, Rong

    2017-02-01

    Injectable hydrogels have a variety of applications, including regenerative medicine, tissue engineering and controlled drug delivery. In this paper, we reported on a pure protein hydrogel based on tetrameric recombinant proteins for the potential drug delivery application. This protein hydrogel was formed instantly by simply mixing two recombinant proteins (ULD-TIP1 and ULD-GGGWRESAI) through the specific protein-peptide interaction. The protein hydrogel was characterized by rheology and scanning electron microscopy (SEM). In vitro cytotoxicity test indicated that the developed protein hydrogel had no apparent cytotoxicity against L-929 cells and HCEC cells after 48h incubation. The formed protein hydrogels was gradually degraded after incubation in phosphate buffered solution (PBS, pH=7.4) for a period of 144h study, as indicated by in vitro degradation test. Encapsulation of model drug (sodium diclofenac; DIC) were achieved by simple mixing of drugs with hydrogelator and the entrapped drugs was almost completely released from hydrogels within 24h via a diffusion manner. As a conclusion, the simple and mild preparation procedure and good biocompatibility of protein hydrogel would render its good promising candidate for drug delivery applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Technical Improvement and Application of Hydrodynamic Gene Delivery in Study of Liver Diseases

    Directory of Open Access Journals (Sweden)

    Mei Huang

    2017-08-01

    Full Text Available Development of an safe and efficient in vivo gene delivery method is indispensable for molecular biology research and the progress in the following gene therapy. Over the past few years, hydrodynamic gene delivery (HGD with naked DNA has drawn increasing interest in both research and potential clinic applications due to its high efficiency and low risk in triggering immune responses and carcinogenesis in comparison to viral vectors. This method, involving intravenous injection (i.v. of massive DNA in a short duration, gives a transient but high in vivo gene expression especially in the liver of small animals. In addition to DNA, it has also been shown to deliver other substance such as RNA, proteins, synthetic small compounds and even viruses in vivo. Given its ability to robustly mimic in vivo hepatitis B virus (HBV production in liver, HGD has become a fundamental and important technology on HBV studies in our group and many other groups. Recently, there have been interesting reports about the applications and further improvement of this technology in other liver research. Here, we review the principle, safety, current application and development of hydrodynamic delivery in liver disease studies, and discuss its future prospects, clinical potential and challenges.

  2. Synthesis, delivery and regulation of eukaryotic heme and Fe-S cluster cofactors.

    Science.gov (United States)

    Barupala, Dulmini P; Dzul, Stephen P; Riggs-Gelasco, Pamela Jo; Stemmler, Timothy L

    2016-02-15

    In humans, the bulk of iron in the body (over 75%) is directed towards heme- or Fe-S cluster cofactor synthesis, and the complex, highly regulated pathways in place to accomplish biosynthesis have evolved to safely assemble and load these cofactors into apoprotein partners. In eukaryotes, heme biosynthesis is both initiated and finalized within the mitochondria, while cellular Fe-S cluster assembly is controlled by correlated pathways both within the mitochondria and within the cytosol. Iron plays a vital role in a wide array of metabolic processes and defects in iron cofactor assembly leads to human diseases. This review describes progress towards our molecular-level understanding of cellular heme and Fe-S cluster biosynthesis, focusing on the regulation and mechanistic details that are essential for understanding human disorders related to the breakdown in these essential pathways. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Synthesis of nir-sensitive Au-Au{sub 2}S nanocolloids for drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Ren, L.; Chow, G.M

    2003-01-15

    Near IR (NIR) sensitive Au-Au{sub 2}S nanocolloids were prepared by mixing HAuCl{sub 4} and Na{sub 2}S in aqueous solutions. An anti-tumor drug, cis-platin, was adsorbed onto Au-Au{sub 2}S nanoparticle surface via the 11-mercaptoundecanoic acid (MUA) layers. The results show that the degree of adsorption of cis-platin onto Au-Au{sub 2}S nanoparticles was controlled by the solution pH value, and the drug release was sensitive to near-infrared irradiation. The cis-platin-loaded Au-Au{sub 2}S nanocolloids can be potentially applied as NIR activated drug delivery carrier.

  4. Carbon-Based Nanomaterials/Allotropes: A Glimpse of Their Synthesis, Properties and Some Applications

    Science.gov (United States)

    Zainal, Zulkarnain; Yusof, Nor Azah

    2018-01-01

    Carbon in its single entity and various forms has been used in technology and human life for many centuries. Since prehistoric times, carbon-based materials such as graphite, charcoal and carbon black have been used as writing and drawing materials. In the past two and a half decades or so, conjugated carbon nanomaterials, especially carbon nanotubes, fullerenes, activated carbon and graphite have been used as energy materials due to their exclusive properties. Due to their outstanding chemical, mechanical, electrical and thermal properties, carbon nanostructures have recently found application in many diverse areas; including drug delivery, electronics, composite materials, sensors, field emission devices, energy storage and conversion, etc. Following the global energy outlook, it is forecasted that the world energy demand will double by 2050. This calls for a new and efficient means to double the energy supply in order to meet the challenges that forge ahead. Carbon nanomaterials are believed to be appropriate and promising (when used as energy materials) to cushion the threat. Consequently, the amazing properties of these materials and greatest potentials towards greener and environment friendly synthesis methods and industrial scale production of carbon nanostructured materials is undoubtedly necessary and can therefore be glimpsed as the focal point of many researchers in science and technology in the 21st century. This is based on the incredible future that lies ahead with these smart carbon-based materials. This review is determined to give a synopsis of new advances towards their synthesis, properties, and some applications as reported in the existing literatures. PMID:29438327

  5. Carbon-Based Nanomaterials/Allotropes: A Glimpse of Their Synthesis, Properties and Some Applications

    Directory of Open Access Journals (Sweden)

    Salisu Nasir

    2018-02-01

    Full Text Available Carbon in its single entity and various forms has been used in technology and human life for many centuries. Since prehistoric times, carbon-based materials such as graphite, charcoal and carbon black have been used as writing and drawing materials. In the past two and a half decades or so, conjugated carbon nanomaterials, especially carbon nanotubes, fullerenes, activated carbon and graphite have been used as energy materials due to their exclusive properties. Due to their outstanding chemical, mechanical, electrical and thermal properties, carbon nanostructures have recently found application in many diverse areas; including drug delivery, electronics, composite materials, sensors, field emission devices, energy storage and conversion, etc. Following the global energy outlook, it is forecasted that the world energy demand will double by 2050. This calls for a new and efficient means to double the energy supply in order to meet the challenges that forge ahead. Carbon nanomaterials are believed to be appropriate and promising (when used as energy materials to cushion the threat. Consequently, the amazing properties of these materials and greatest potentials towards greener and environment friendly synthesis methods and industrial scale production of carbon nanostructured materials is undoubtedly necessary and can therefore be glimpsed as the focal point of many researchers in science and technology in the 21st century. This is based on the incredible future that lies ahead with these smart carbon-based materials. This review is determined to give a synopsis of new advances towards their synthesis, properties, and some applications as reported in the existing literatures.

  6. Reversible logic synthesis methodologies with application to quantum computing

    CERN Document Server

    Taha, Saleem Mohammed Ridha

    2016-01-01

    This book opens the door to a new interesting and ambitious world of reversible and quantum computing research. It presents the state of the art required to travel around that world safely. Top world universities, companies and government institutions  are in a race of developing new methodologies, algorithms and circuits on reversible logic, quantum logic, reversible and quantum computing and nano-technologies. In this book, twelve reversible logic synthesis methodologies are presented for the first time in a single literature with some new proposals. Also, the sequential reversible logic circuitries are discussed for the first time in a book. Reversible logic plays an important role in quantum computing. Any progress in the domain of reversible logic can be directly applied to quantum logic. One of the goals of this book is to show the application of reversible logic in quantum computing. A new implementation of wavelet and multiwavelet transforms using quantum computing is performed for this purpose. Rese...

  7. Nanoporous ionic organic networks: from synthesis to materials applications.

    Science.gov (United States)

    Sun, Jian-Ke; Antonietti, Markus; Yuan, Jiayin

    2016-11-21

    The past decade has witnessed rapid progress in the synthesis of nanoporous organic networks or polymer frameworks for various potential applications. Generally speaking, functionalization of porous networks to add extra properties and enhance materials performance could be achieved either during the pore formation (thus a concurrent approach) or by post-synthetic modification (a sequential approach). Nanoporous organic networks which include ion pairs bound in a covalent manner are of special importance and possess extreme application profiles. Within these nanoporous ionic organic networks (NIONs), here with a pore size in the range from sub-1 nm to 100 nm, we observe a synergistic coupling of the electrostatic interaction of charges, the nanoconfinement within pores and the addressable functional units in soft matter resulting in a wide variety of functions and applications, above all catalysis, energy storage and conversion, as well as environment-related operations. This review aims to highlight the recent progress in this area, and seeks to raise original perspectives that will stimulate future advancements at both the fundamental and applied level.

  8. Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches

    Science.gov (United States)

    Zhang, Xi-Feng; Liu, Zhi-Guo; Shen, Wei; Gurunathan, Sangiliyandi

    2016-01-01

    Recent advances in nanoscience and nanotechnology radically changed the way we diagnose, treat, and prevent various diseases in all aspects of human life. Silver nanoparticles (AgNPs) are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. AgNPs play an important role in nanoscience and nanotechnology, particularly in nanomedicine. Although several noble metals have been used for various purposes, AgNPs have been focused on potential applications in cancer diagnosis and therapy. In this review, we discuss the synthesis of AgNPs using physical, chemical, and biological methods. We also discuss the properties of AgNPs and methods for their characterization. More importantly, we extensively discuss the multifunctional bio-applications of AgNPs; for example, as antibacterial, antifungal, antiviral, anti-inflammatory, anti-angiogenic, and anti-cancer agents, and the mechanism of the anti-cancer activity of AgNPs. In addition, we discuss therapeutic approaches and challenges for cancer therapy using AgNPs. Finally, we conclude by discussing the future perspective of AgNPs. PMID:27649147

  9. Synthesis and applications of MOF-derived porous nanostructures

    Directory of Open Access Journals (Sweden)

    Min Hui Yap

    2017-07-01

    Full Text Available Metal organic frameworks (MOFs represent a class of porous material which is formed by strong bonds between metal ions and organic linkers. By careful selection of constituents, MOFs can exhibit very high surface area, large pore volume, and excellent chemical stability. Research on synthesis, structures and properties of various MOFs has shown that they are promising materials for many applications, such as energy storage, gas storage, heterogeneous catalysis and sensing. Apart from direct use, MOFs have also been used as support substrates for nanomaterials or as sacrificial templates/precursors for preparation of various functional nanostructures. In this review, we aim to present the most recent development of MOFs as precursors for the preparation of various nanostructures and their potential applications in energy-related devices and processes. Specifically, this present survey intends to push the boundaries and covers the literatures from the year 2013 to early 2017, on supercapacitors, lithium ion batteries, electrocatalysts, photocatalyst, gas sensing, water treatment, solar cells, and carbon dioxide capture. Finally, an outlook in terms of future challenges and potential prospects towards industrial applications are also discussed. Keywords: Metal organic frameworks, Porous nanostructures, Supercapacitors, Lithium ion batteries, Heterogeneous catalyst

  10. Anisotropic gold nanoparticles: synthesis, properties, applications, and toxicity.

    Science.gov (United States)

    Li, Na; Zhao, Pengxiang; Astruc, Didier

    2014-02-10

    Anisotropic gold nanoparticles (AuNPs) have attracted the interest of scientists for over a century, but research in this field has considerably accelerated since 2000 with the synthesis of numerous 1D, 2D, and 3D shapes as well as hollow AuNP structures. The anisotropy of these nonspherical, hollow, and nanoshell AuNP structures is the source of the plasmon absorption in the visible region as well as in the near-infrared (NIR) region. This NIR absorption is especially sensitive to the AuNP shape and medium and can be shifted towards the part of the NIR region in which living tissue shows minimum absorption. This has led to crucial applications in medical diagnostics and therapy ("theranostics"), especially with Au nanoshells, nanorods, hollow nanospheres, and nanocubes. In addition, Au nanowires (AuNWs) can be synthesized with longitudinal dimensions of several tens of micrometers and can serve as plasmon waveguides for sophisticated optical devices. The application of anisotropic AuNPs has rapidly spread to optical, biomedical, and catalytic areas. In this Review, a brief historical survey is given, followed by a summary of the synthetic modes, variety of shapes, applications, and toxicity issues of this fast-growing class of nanomaterials. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Synthesis, characterization, applications, and challenges of iron oxide nanoparticles

    Science.gov (United States)

    Ali, Attarad; Zafar, Hira; Zia, Muhammad; ul Haq, Ihsan; Phull, Abdul Rehman; Ali, Joham Sarfraz; Hussain, Altaf

    2016-01-01

    Recently, iron oxide nanoparticles (NPs) have attracted much consideration due to their unique properties, such as superparamagnetism, surface-to-volume ratio, greater surface area, and easy separation methodology. Various physical, chemical, and biological methods have been adopted to synthesize magnetic NPs with suitable surface chemistry. This review summarizes the methods for the preparation of iron oxide NPs, size and morphology control, and magnetic properties with recent bioengineering, commercial, and industrial applications. Iron oxides exhibit great potential in the fields of life sciences such as biomedicine, agriculture, and environment. Nontoxic conduct and biocompatible applications of magnetic NPs can be enriched further by special surface coating with organic or inorganic molecules, including surfactants, drugs, proteins, starches, enzymes, antibodies, nucleotides, nonionic detergents, and polyelectrolytes. Magnetic NPs can also be directed to an organ, tissue, or tumor using an external magnetic field for hyperthermic treatment of patients. Keeping in mind the current interest in iron NPs, this review is designed to report recent information from synthesis to characterization, and applications of iron NPs. PMID:27578966

  12. Synthesis, Characterization, and Applications of Magnetic Nanoparticles Featuring Polyzwitterionic Coatings

    Directory of Open Access Journals (Sweden)

    Philip Biehl

    2018-01-01

    Full Text Available Throughout the last decades, magnetic nanoparticles (MNP have gained tremendous interest in different fields of applications like biomedicine (e.g., magnetic resonance imaging (MRI, drug delivery, hyperthermia, but also more technical applications (e.g., catalysis, waste water treatment have been pursued. Different surfactants and polymers are extensively used for surface coating of MNP to passivate the surface and avoid or decrease agglomeration, decrease or modulate biomolecule absorption, and in most cases increase dispersion stability. For this purpose, electrostatic or steric repulsion can be exploited and, in that regard, surface charge is the most important (hybrid particle property. Therefore, polyelectrolytes are of great interest for nanoparticle coating, as they are able to stabilize the particles in dispersion by electrostatic repulsion due to their high charge densities. In this review article, we focus on polyzwitterions as a subclass of polyelectrolytes and their use as coating materials for MNP. In the context of biomedical applications, polyzwitterions are widely used as they exhibit antifouling properties and thus can lead to minimized protein adsorption and also long circulation times.

  13. Poly(amidoamine) (PAMAM) dendrimers: from biomimicry to drug delivery and biomedical applications.

    Science.gov (United States)

    Esfand, R; Tomalia, D A.

    2001-04-01

    Poly(amidoamine) (PAMAM) dendrimers are the first complete dendrimer family to be synthesized, characterized and commercialized. Based on this extensive activity, they are recognized as a unique new class of synthetic nanostructures. Dendrimers allow the precise control of size, shape and placement of functional groups that is desirable for many life science applications. From this perspective, this review focuses on crucial properties of biomimetic dendrimers that will broaden the potential for their use as macromolecular vectors in novel drug delivery and biomedical applications.

  14. iPhone application development strategies for efficient mobile design and delivery

    CERN Document Server

    Hahn, Jim

    2011-01-01

    iPhone application development is explained here in an accessible treatment for the generalist Library and Information Science (LIS) practitioner. Future information-seeking practices by users will take place across a diverse array of ubiquitous computing devices. iPhone applications represent one of the most compelling new platforms for which to remediate and re-engineer library service. Strategies of efficient mobile design and delivery include adapting computing best practices of data independence and adhering to web standards as articulated by the W3C. These best practices apply across the

  15. Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Kanapathipillai, Mathumai [Iowa State Univ., Ames, IA (United States)

    2008-01-01

    Self-assembly is a powerful tool in forming structures with nanoscale dimensions. Self-assembly of macromolecules provides an efficient and rapid pathway for the formation of structures from the nanometer to micrometer range that are difficult, if not impossible to obtain by conventional lithographic techniques [1]. Depending on the morphologies obtained (size, shape, periodicity, etc.) these self-assembled systems have already been applied or shown to be useful for a number of applications in nanotechnology [2], biomineralization [3, 4], drug delivery [5, 6] and gene therapy [7]. In this respect, amphiphilic block copolymers that self-organize in solution have been found to be very versatile [1]. In recent years, polymer-micellar systems have been designed that are adaptable to their environment and able to respond in a controlled manner to external stimuli. In short, synthesis of 'nanoscale objects' that exhibit 'stimulus-responsive' properties is a topic gathering momentum, because their behavior is reminiscent of that exhibited by proteins [8]. By integrating environmentally sensitive homopolymers into amphiphilic block copolymers, smart block copolymers with self assembled supramolecular structures that exhibit stimuli or environmentally responsive properties can be obtained [1]. Several synthetic polymers are known to have environmentally responsive properties. Changes in the physical, chemical or biochemical environment of these polymers results in modulation of the solubility or chain conformation of the polymer [9]. There are many common schemes of engineering stimuli responsive properties into materials [8, 9]. Polymers exhibiting lower critical solution temperature (LCST) are soluble in solvent below a specific temperature and phase separate from solvent above that temperature while polymers exhibiting upper critical solution temperatures (UCST) phase separate below a certain temperature. The solubility of polymers with ionizable

  16. Gas-phase synthesis of semiconductor nanocrystals and its applications

    Science.gov (United States)

    Mandal, Rajib

    Luminescent nanomaterials is a newly emerging field that provides challenges not only to fundamental research but also to innovative technology in several areas such as electronics, photonics, nanotechnology, display, lighting, biomedical engineering and environmental control. These nanomaterials come in various forms, shapes and comprises of semiconductors, metals, oxides, and inorganic and organic polymers. Most importantly, these luminescent nanomaterials can have different properties owing to their size as compared to their bulk counterparts. Here we describe the use of plasmas in synthesis, modification, and deposition of semiconductor nanomaterials for luminescence applications. Nanocrystalline silicon is widely known as an efficient and tunable optical emitter and is attracting great interest for applications in several areas. To date, however, luminescent silicon nanocrystals (NCs) have been used exclusively in traditional rigid devices. For the field to advance towards new and versatile applications for nanocrystal-based devices, there is a need to investigate whether these NCs can be used in flexible and stretchable devices. We show how the optical and structural/morphological properties of plasma-synthesized silicon nanocrystals (Si NCs) change when they are deposited on stretchable substrates made of polydimethylsiloxane (PDMS). Synthesis of these NCs was performed in a nonthermal, low-pressure gas phase plasma reactor. To our knowledge, this is the first demonstration of direct deposition of NCs onto stretchable substrates. Additionally, in order to prevent oxidation and enhance the luminescence properties, a silicon nitride shell was grown around Si NCs. We have demonstrated surface nitridation of Si NCs in a single step process using non?thermal plasma in several schemes including a novel dual-plasma synthesis/shell growth process. These coated NCs exhibit SiNx shells with composition depending on process parameters. While measurements including

  17. Synthesis and evaluation of cationic nanomicelles for in vitro and in vivo gene delivery

    Science.gov (United States)

    Mandke, Rhishikesh Subhash

    The goal of proposed study was to contribute towards the development of a nano size, high efficiency and low toxicity non-viral polymeric vector for gene delivery in vitro and in vivo. A series of fatty acid grafted low-molecular-weight chitosan (N-acyl LMWCs) were synthesized, purified and characterized for their physicochemical properties using various analytical techniques such as infrared spectroscopy, elemental analysis and dynamic light scattering. The formulation parameters including pH, sonication duration, and filtration altered the physicochemical characteristics of N-acyl LMWC nanomicelles. The acyl chain length and degree of unsaturation in fatty acids also had an impact on the physicochemical properties and the transfection efficiency of nanomicelles. N-acyl LMWC nanomicelles showed efficient in vitro transfection as visualized and quantified using a reporter plasmid (encoding green fluorescent protein), and therapeutic plasmids (encoding for interleukin-4 and interleukin-10), respectively. The in vitro transfection efficiencies of N-acyl LMWCs with 18:1 and 18:2 grafts (oleic and linoleic acids) were comparable with FuGENERTM HD (marketed non-viral vector) but were ˜8-fold and 35-fold higher as compared to LMWC and naked DNA, respectively. The in vivo transfection efficiency of N-acyl LMWC to deliver plasmids individually encoding IL-4 and IL-10 as well as a bicistronic plasmid encoding both IL-4 and IL-10 was studied in a multiple, low-dose streptozotocin induced diabetic mouse model. The transfection efficiency of pDNA/N-acyl LMWC polyplexes injected via intramuscular route showed significant improvement (ptumor necrosis factor-alpha (TNF-alpha) levels. The pancreas of pDNA/N-acyl LMWC polyplex treated animals exhibited protection from streptozotocin-induced insulitis and the delivery systems were biocompatible. Histological studies revealed that there were no signs of chronic inflammation at the injection site. The bicistronic plasmid exhibited

  18. Nanotechnology-based polymeric bio(muco)adhesive platforms for controlling drug delivery - properties, methodologies and applications

    International Nuclear Information System (INIS)

    Carvalho, Flavia Chiva; Chorilli, Marlus; Gremiao, Maria Palmira Daflon

    2014-01-01

    Studies using bio(muco)adhesive drug delivery systems have recently gained great interest, which can promote drug targeting and more specific contact of the drug delivery system with the various absorptive membranes of the body. This technological platform associated with nanotechnology offers potential for controlling drug delivery; therefore, they are excellent strategies to increase the bioavailability of drugs. The objective of this work was to study nanotechnology-based polymeric bio(muco)adhesive platforms for controlling drug delivery, highlighting their properties, how the bio(muco)adhesion can be measured and their potential applications for different routes of administration. (author)

  19. Synthesis of new thermo/pH sensitive drug delivery systems based on tragacanth gum polysaccharide.

    Science.gov (United States)

    Hemmati, Khadijeh; Ghaemy, Mousa

    2016-06-01

    In this study, new pH/temperature responsive graft copolymers were synthesized based on natural Tragacanth Gum (TG) carbohydrate and their controlled drug release was investigated. Amphiphilic alkyne terminated terpolymers (mPEG-PCL-PDMAEMA-CCH)s consist of methylated poly(ethyleneglycol) (mPEG), polycaprolactone (PCL), and poly(dimethylaminoethylmethacrylate) (PDMAEMA) were synthesized by using ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP), and then were grafted onto azide-functionalized TG molecules by click chemistry. Different techniques such as FT-IR, (1)H NMR, gel permeation chromatography (GPC), thermo-gravimetrical analysis (TGA) and scanning electron microscopy (SEM) were used to verify the successful synthesis of graft copolymers (TG-g-PDMAEMA-PCL-mPEG)s. The graft copolymers self-assembled to single micelles in aqueous solution and upon pH changes further assembled into micellar aggregates. These micelles were used to prepare quercetin loaded nanocarriers by probe sonication method. Size and morphology of the nanocarriers were studied by dynamic light scattering (DLS) and SEM. The in vitro release behavior of quercetin from these micelles showed pH-dependence. The results showed that release profile of quercetin best followed the first order model. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Synthesis of nanohydrogels based on tragacanth gum biopolymer and investigation of swelling and drug delivery.

    Science.gov (United States)

    Sadat Hosseini, Masoomeh; Hemmati, Khadijeh; Ghaemy, Mousa

    2016-01-01

    The present article deals with preparation of pH responsive nanohydrogels based on tragacanth gum (TG) biopolymer for drug delivery. The nanohydrogels were prepared using different chemical reagents such as 3-aminopropyltriethoxysilane (APTES) modifier and glyceroldiglycidylether (GDE), polyvinyl alcohol (PVA), and glutaraldehyde (GA) as cross-linkers. The obtained nanohydrogels were characterized using different techniques such as scanning electron microscope (SEM), elemental analysis, FT-IR, zeta sizer and thermogravimetric analysis (TGA). The gel content increased with increasing the cross-linkers contents and reached to a maximum of 90%. The swelling behavior of nanohydrogels was investigated in terms of the effect of pH (2.2, 7.4 and 9), temperature (27, 37 and 60°C), and reaction time (2-24h). Loading of Indomethacin (IND) as a model drug showed dependence on the network structure of nanohydrogels. The total in vitro IND release showed dependence on the network structure of nanohydrogels and was in the range of 50-80% at pH 9 after 24h. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Synthesis and Properties of Star HPMA Copolymer Nanocarriers Synthesised by RAFT Polymerisation Designed for Selective Anticancer Drug Delivery and Imaging.

    Science.gov (United States)

    Chytil, Petr; Koziolová, Eva; Janoušková, Olga; Kostka, Libor; Ulbrich, Karel; Etrych, Tomáš

    2015-06-01

    High-molecular-weight star polymer drug nanocarriers intended for the treatment and/or visualisation of solid tumours were synthesised, and their physico-chemical and preliminary in vitro biological properties were determined. The water-soluble star polymer carriers were prepared by the grafting of poly(amido amine) (PAMAM) dendrimers by hetero-telechelic N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers, synthesised by the controlled radical Reversible Addition Fragmentation chain Transfer (RAFT) polymerisation. The well-defined star copolymers with Mw values ranging from 2 · 10(5) to 6 · 10(5) showing a low dispersity (approximately 1.2) were prepared in a high yield. A model anticancer drug, doxorubicin, was bound to the star polymer through a hydrazone bond, enabling the pH-controlled drug release in the target tumour tissue. The activated polymer arm ends of the star copolymer carrier enable a one-point attachment for the targeting ligands and/or a labelling moiety. In this study, the model TAMRA fluorescent dye was used to prove the feasibility of the polymer carrier visualisation by optical imaging in vitro. The tailor-made structure of the star polymer carriers should facilitate the synthesis of targeted polymer-drug conjugates, even polymer theranostics, for simultaneous tumour drug delivery and imaging. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. The application of carbon nanotubes in target drug delivery systems for cancer therapies

    Science.gov (United States)

    Zhang, Wuxu; Zhang, Zhenzhong; Zhang, Yingge

    2011-10-01

    Among all cancer treatment options, chemotherapy continues to play a major role in killing free cancer cells and removing undetectable tumor micro-focuses. Although chemotherapies are successful in some cases, systemic toxicity may develop at the same time due to lack of selectivity of the drugs for cancer tissues and cells, which often leads to the failure of chemotherapies. Obviously, the therapeutic effects will be revolutionarily improved if human can deliver the anticancer drugs with high selectivity to cancer cells or cancer tissues. This selective delivery of the drugs has been called target treatment. To realize target treatment, the first step of the strategies is to build up effective target drug delivery systems. Generally speaking, such a system is often made up of the carriers and drugs, of which the carriers play the roles of target delivery. An ideal carrier for target drug delivery systems should have three pre-requisites for their functions: (1) they themselves have target effects; (2) they have sufficiently strong adsorptive effects for anticancer drugs to ensure they can transport the drugs to the effect-relevant sites; and (3) they can release the drugs from them in the effect-relevant sites, and only in this way can the treatment effects develop. The transporting capabilities of carbon nanotubes combined with appropriate surface modifications and their unique physicochemical properties show great promise to meet the three pre-requisites. Here, we review the progress in the study on the application of carbon nanotubes as target carriers in drug delivery systems for cancer therapies.

  3. Core-shell designs of photoluminescent nanodiamonds with porous silica coatings for bioimaging and drug delivery, II : Application

    NARCIS (Netherlands)

    Prabhakar, N.; Näreoja, T.; Haartman, Von E.; Karaman, D.S.; Jiang, H.; Koho, S.; Dolenko, T.A.; Hänninen, P.E.; Vlasov, D.I.; Ralchenko, V.G.; Hosomi, S.; Vlasov, I.I.; Sahlgren, C.M.; Rosenholm, J.M.

    2013-01-01

    Recent advances within materials science and its interdisciplinary applications in biomedicine have emphasized the potential of using a single multifunctional composite material for concurrent drug delivery and biomedical imaging. Here we present a novel composite material consisting of a

  4. Anticancer Activities of Surfactin and Potential Application of Nanotechnology Assisted Surfactin Delivery

    Directory of Open Access Journals (Sweden)

    Yuan-Seng Wu

    2017-10-01

    Full Text Available Surfactin, a cyclic lipopeptide biosurfactant produced by various strains of Bacillus genus, has been shown to induce cytotoxicity against many cancer types, such as Ehrlich ascites, breast and colon cancers, leukemia and hepatoma. Surfactin treatment can inhibit cancer progression by growth inhibition, cell cycle arrest, apoptosis, and metastasis arrest. Owing to the potent effect of surfactin on cancer cells, numerous studies have recently investigated the mechanisms that underlie its anticancer activity. The amphiphilic nature of surfactin allows its easy incorporation nano-formulations, such as polymeric nanoparticles, micelles, microemulsions, liposomes, to name a few. The use of nano-formulations offers the advantage of optimizing surfactin delivery for an improved anticancer therapy. This review focuses on the current knowledge of surfactin properties and biosynthesis; anticancer activity against different cancer models and the underlying mechanisms involved; as well as the potential application of nano-formulations for optimal surfactin delivery.

  5. Coupling surfactants with permanganate for DNAPL removal : coinjection or sequential application as delivery methods

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, P.J. [Carus Corp., Peru, IL (United States); Siegrist, R.L. [Colorado School of Mines, Golden, CO (United States); Crimi, M.L. [Clarkson Univ., Potsdam, NY (United States)

    2010-07-01

    This PowerPoint presentation described a study conducted to test the effectiveness of surfactant-enhanced permanganate for the remediation of dense nonaqueous phase liquids (DNAPL). When DNAPL enters the environment, it can pollute millions of gallons of ground water and create huge dissolved plumes that act as long-term sources of contamination. Surfactants were used to enhance the solubilization and mobilization of DNAPL during the remediation process. In situ chemical oxidation (ISCO) was then used to deliver oxidants into the sub-surface to destroy organic contaminants in the soil and ground water. Experimental 2-D flow-through cell studies of 72 surfactants were conducted with the permanganate to evaluate delivery methods and determine compatible co-solvents for the surfactant process. Delivery methods included co-injection and sequential application. Four compatible surfactants were found to be compatible with the permanganate. A 90 percent DNAPL remediation rate was achieved using relatively low surfactant and oxidant concentrations. tabs., figs.

  6. Extended Delivery Time Analysis for Cognitive Packet Transmission With Application to Secondary Queuing Analysis

    KAUST Repository

    Usman, Muneer

    2015-05-21

    Cognitive radio transceiver can opportunistically access the underutilized spectrum resource of primary systems for new wireless services. With interweave implementation, the secondary transmission may be interrupted by the primary user\\'s transmission. To facilitate the delay analysis of such secondary transmission for fixed-size secondary packets, we study the resulting extended delivery time that includes both transmission time and waiting time. In particular, we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical and simulation results are presented for illustrating the mathematical formulation. Finally, we consider an M/G/1 queueing set-up at the secondary transmitter and formulate the closed-form expressions for the expected delay with Poisson traffic. The analytical results will greatly facilitate the design of the secondary system for particular target application. © 2015 IEEE.

  7. Synthesis of internally functionalized silica nanoparticles for theranostic applications

    Science.gov (United States)

    Walton, Nathan Isaac

    This thesis addresses the synthesis and characterization of novel inorganic silica nanoparticle hybrids. It focuses in large part on their potential applications in the medical field. Silica acts as a useful carrier for a variety of compounds and this thesis silica will demonstrate its use as a carrier for boron or gadolinium. Boron-10 and gadolinium-157 have been suggested for the radiological treatment of tumor cells through the process called neutron capture therapy (NCT). Gadolinium is also commonly used as a Magnetic Resonance Imaging (MRI) contrast agent. Particles that carry it have potential theranostic applications of both imaging and treating tumors. Chapter 1 presents a background on synthetic strategies and usages of silica nanoparticles, and NCT theory. Chapter 2 describes a procedure to create mesoporous metal chelating silica nanoparticles, mDTTA. This is achieved via a co-condensation of tetraethoxysilane (TEOS) and 3-trimethoxysilyl-propyl diethylenetriamine (SiDETA) followed by a post-synthesis modification step with bromoacetic acid (BrAA). These particles have a large surface area and well-defined pores of ~2 nm. The mDTTA nanoparticles were used to chelate the copper(II), cobalt(II) and gadolinium(III). The chelating of gadolinium is the most interesting since it can be used as a MRI contrast agent and a neutron capture therapeutic. The synthetic procedure developed also allows for the attachment of a fluorophore that gives the gadolinium chelating mDTTA nanoparticles a dual imaging modality. Chapter 3 presents the synthetic method used to produce two classes of large surface area organically modified silica (ORMOSIL) nanoparticles. Condensating the organosilane vinyltrimethoxysilane in a micellar solution results in nanoparticles that are either surface rough (raspberry-like) or mesoporous nanoparticles, which prior to this thesis has not been demonstrated in ORMOSIL chemistry. Furthermore, the vinyl functionalities are modified, using

  8. Synthesis and Evaluation of Tetramethylguanidinium-Polyethylenimine Polymers as Efficient Gene Delivery Vectors

    Directory of Open Access Journals (Sweden)

    Manohar Mahato

    2014-01-01

    Full Text Available Previously, we demonstrated that 6-(N,N,N′,N′-tetramethylguanidinium chloride-hexanoyl-polyethylenimine (THP polymers exhibited significantly enhanced transfection efficiency and cell viability. Here, in the present study, we have synthesized a series of N,N,N′,N′-tetramethylguanidinium-polyethylenimine (TP1-TP5 polymers via a single-step reaction involving peripheral primary amines of bPEI and varying amounts of 2-(1H-benzotriazol-1-yl-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU. These polymers were found to interact efficiently with negatively charged pDNA and formed stable complexes in the size range of ~240–450 nm. Acid-base titration profiles revealed improved buffering capacity of TP polymers as compared to bPEI. Transfection and cytotoxicity assays performed with TP/pDNA complexes on HEK293, CHO, and HeLa cells showed significantly higher transfection efficiency and cell viability with one of the complexes, TP2/pDNA complex, exhibited the highest transfection efficiency (~1.4–2.3-fold outcompeting native bPEI and the commercially available transfection reagent, Lipofectamine 2000. Compared to previously reported THP polymers, the transfection efficiency of TP/pDNA complexes was found to be lower, as examined by flow cytometry. These results highlight the importance of the hydrophobic C-6 linker in THP polymers in forming compact nanostructures with pDNA, which might lead to efficient uptake and internalization of the complexes; however, the projected TP polymers offer an advantage of their rapid and economical one-step synthesis.

  9. Synthesis and evaluation of tetramethylguanidinium-polyethylenimine polymers as efficient gene delivery vectors.

    Science.gov (United States)

    Mahato, Manohar; Yadav, Santosh; Kumar, Pradeep; Sharma, Ashwani Kumar

    2014-01-01

    Previously, we demonstrated that 6-(N,N,N',N'-tetramethylguanidinium chloride)-hexanoyl-polyethylenimine (THP) polymers exhibited significantly enhanced transfection efficiency and cell viability. Here, in the present study, we have synthesized a series of N,N,N',N'-tetramethylguanidinium-polyethylenimine (TP1-TP5) polymers via a single-step reaction involving peripheral primary amines of bPEI and varying amounts of 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU). These polymers were found to interact efficiently with negatively charged pDNA and formed stable complexes in the size range of ~240-450 nm. Acid-base titration profiles revealed improved buffering capacity of TP polymers as compared to bPEI. Transfection and cytotoxicity assays performed with TP/pDNA complexes on HEK293, CHO, and HeLa cells showed significantly higher transfection efficiency and cell viability with one of the complexes, TP2/pDNA complex, exhibited the highest transfection efficiency (~1.4-2.3-fold) outcompeting native bPEI and the commercially available transfection reagent, Lipofectamine 2000. Compared to previously reported THP polymers, the transfection efficiency of TP/pDNA complexes was found to be lower, as examined by flow cytometry. These results highlight the importance of the hydrophobic C-6 linker in THP polymers in forming compact nanostructures with pDNA, which might lead to efficient uptake and internalization of the complexes; however, the projected TP polymers offer an advantage of their rapid and economical one-step synthesis.

  10. Synthesis and characterization of amino acid-functionalized calcium phosphate nanoparticles for siRNA delivery.

    Science.gov (United States)

    Bakan, Feray; Kara, Goknur; Cokol Cakmak, Melike; Cokol, Murat; Denkbas, Emir Baki

    2017-10-01

    Small interfering RNAs (siRNA) are short nucleic acid fragments of about 20-27 nucleotides, which can inhibit the expression of specific genes. siRNA based RNAi technology has emerged as a promising method for the treatment of a variety of diseases. However, a major limitation in the therapeutic use of siRNA is its rapid degradation in plasma and cellular cytoplasm, resulting in short half-life. In addition, as siRNA molecules cannot penetrate into the cell efficiently, it is required to use a carrier system for its delivery. In this work, chemically and morphologically different calcium phosphate (CaP) nanoparticles, including spherical-like hydroxyapatite (HA-s), needle-like hydroxyapatite (HA-n) and calcium deficient hydroxyapatite (CDHA) nanoparticles were synthesized by the sol-gel technique and the effects of particle characteristics on the binding capacity of siRNA were investigated. In order to enhance the gene loading efficiency, the nanoparticles were functionalized with arginine and the morphological and their structural characteristics were analyzed. The addition of arginine did not significantly change the particle sizes; however, it provided a significantly increased binding of siRNA for all types of CaP nanoparticles, as revealed by spectrophotometric measurements analysis. Arginine functionalized HA-n nanoparticles showed the best binding behavior with siRNA among the other nanoparticles due to its high, positive zeta potential (+18.8mV) and high surface area of Ca ++ rich "c" plane. MTT cytotoxicity assays demonstrated that all the nanoparticles tested herein were biocompatible. Our results suggest that high siRNA entrapment in each of the three modified non-toxic CaP nanoparticles make them promising candidates as a non-viral vector for delivering therapeutic siRNA molecules to treat cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. A brief review on synthesis & applications of β-enamino carbonyl compounds

    Directory of Open Access Journals (Sweden)

    yellajyosula L N Murthy

    2012-01-01

    Full Text Available Owing to the wide range applications of β-enamino esters (enamines of β–dicarbonyl compounds in pharmaceuticals and as building blocks for the synthesis of a variety of heterocyclic compounds, β-amino esters, β-amino acids, γ-amino alcohols, peptides and alkaloids a number of methods have been developed so far for the synthesis of these compounds. Due to the importance of these compounds as intermediates in organic synthesis, a concised review is presented.

  12. Tuned apatitic materials: Synthesis, characterization and potential antimicrobial applications

    Science.gov (United States)

    Fierascu, Irina; Fierascu, Radu Claudiu; Somoghi, Raluca; Ion, Rodica Mariana; Moanta, Adriana; Avramescu, Sorin Marius; Damian, Celina Maria; Ditu, Lia Mara

    2018-04-01

    Inorganic antimicrobial materials can be viable for multiple applications (related to its use for new buildings with special requirements related to microbiological loading, such as hospital buildings and for consolidation of cultural heritage constructions); also the use of substituted hydroxyapatites for protection of stone artefacts against environmental factors (acidic rain) and biodeterioration it's an option to no longer use of toxic substances. This paper presents methods of synthesis and characterization of the material from the point of view of the obtained structures and final applications. The materials were characterized in terms of composition and morphology (using X-ray Diffraction, X-ray Fluorescence, Inductively coupled plasma-atomic emission spectrometry, Fourier Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, Surface area and pore size determination). Antimicrobial activity was tested against filamentous fungi strains and pathogenic bacteria strains, using both spot on lawn qualitative method (on agar medium) and serial microdilution quantitative method (in broth medium). Further, it was evaluated the anti-biofilm activity of the tested samples toward the most important microbial strains implicated in biofilm development, using crystal violet stained biofilms microtiter assay, followed by spectrophotometric quantitative evaluation.

  13. Synthesis, characterisation and biomedical applications of curcumin conjugated chitosan microspheres.

    Science.gov (United States)

    Saranya, T S; Rajan, V K; Biswas, Raja; Jayakumar, R; Sathianarayanan, S

    2018-04-15

    Curcumin is a diaryl heptanoid of curcuminoids class obtained from Curcuma longa. It possesses various biological activities like anti-inflammatory, hypoglycemic, antioxidant, wound-healing, and antimicrobial activities. Chitosan is a biocompatible, biodegradable and non-toxic natural polymer which enhances the adhesive property of the skin. Chemical conjugation will leads to sustained release action and to enhance the bioavailability. This study aims to synthesis and characterize biocompatible curcumin conjugated chitosan microspheres for bio-medical applications. The Schiff base reaction was carried out for the preparation of curcumin conjugated chitosan by microwave method and it was characterised using FTIR and NMR. Curcumin conjugated chitosan microspheres (CCCMs) were prepared by wet milling solvent evaporation method. SEM analysis showed these CCCMs were 2-5μm spherical particles. The antibacterial activities of the prepared CCCMs were studied against Staphylococcus aureus and Escherichia coli, the zone of inhibition was 28mm and 23mm respectively. Antioxidant activity of the prepared CCCMs was also studied by DPPH and H 2 O 2 method it showed IC 50 esteem value of 216μg/ml and 228μg/ml, and anti-inflammatory activity results showed that CCCMs having IC 50 value of 45μg/ml. The results conclude that the CCCMs having a good antibacterial, antioxidant and anti-inflammatory activities. This, the prepared CCCMs have potential application in preventing skin infections. Copyright © 2017. Published by Elsevier B.V.

  14. Synthesis and characterization of robust magnetic carriers for bioprocess applications

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Willian, E-mail: willkopp@gmail.com [Federal University of São Carlos-UFSCar, Graduate Program in Chemical Engineering, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); Silva, Felipe A., E-mail: eq.felipe.silva@gmail.com [Federal University of São Carlos-UFSCar, Graduate Program in Chemical Engineering, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); Lima, Lionete N., E-mail: lionetenunes@yahoo.com.br [Federal University of São Carlos-UFSCar, Graduate Program in Chemical Engineering, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); Masunaga, Sueli H., E-mail: sueli.masunaga@gmail.com [Department of Physics, Montana State University-MSU, 173840, Bozeman, MT 59717-3840 (United States); Tardioli, Paulo W., E-mail: pwtardioli@ufscar.br [Department of Chemical Engineering, Federal University of São Carlos-UFSCar, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); Giordano, Roberto C., E-mail: roberto@ufscar.br [Department of Chemical Engineering, Federal University of São Carlos-UFSCar, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); Araújo-Moreira, Fernando M., E-mail: faraujo@df.ufscar.br [Department of Physics, Federal University of São Carlos-UFSCar, Rodovia Washington Luiz, km 235, São Carlos, São Paulo 13565-905 (Brazil); and others

    2015-03-15

    Highlights: • Silica magnetic microparticles were synthesized for applications in bioprocesses. • The process to produce magnetic microparticles is inexpensive and easily scalable. • Microparticles with very high saturation magnetization were obtained. • The structure of the silica magnetic microparticles could be controlled. - Abstract: Magnetic carriers are an effective option to withdraw selected target molecules from complex mixtures or to immobilize enzymes. This paper describes the synthesis of robust silica magnetic microparticles (SMMps), particularly designed for applications in bioprocesses. SMMps were synthesized in a micro-emulsion, using sodium silicate as the silica source and superparamagnetic iron oxide nanoparticles as the magnetic core. Thermally resistant particles, with high and accessible surface area, narrow particle size distribution, high saturation magnetization, and with superparamagnetic properties were obtained. Several reaction conditions were tested, yielding materials with saturation magnetization between 45 and 63 emu g{sup −1}, particle size between 2 and 200 μm and average diameter between 11.2 and 15.9 μm, surface area between 49 and 103 m{sup 2} g{sup −1} and pore diameter between 2 and 60 nm. The performance of SMMps in a bioprocess was evaluated by the immobilization of Pseudomonas fluorescens lipase on to octyl modified SMMp, the biocatalyst obtained was used in the production of butyl butyrate with good results.

  15. Bottom-Up Synthesis and Sensor Applications of Biomimetic Nanostructures

    Directory of Open Access Journals (Sweden)

    Li Wang

    2016-01-01

    Full Text Available The combination of nanotechnology, biology, and bioengineering greatly improved the developments of nanomaterials with unique functions and properties. Biomolecules as the nanoscale building blocks play very important roles for the final formation of functional nanostructures. Many kinds of novel nanostructures have been created by using the bioinspired self-assembly and subsequent binding with various nanoparticles. In this review, we summarized the studies on the fabrications and sensor applications of biomimetic nanostructures. The strategies for creating different bottom-up nanostructures by using biomolecules like DNA, protein, peptide, and virus, as well as microorganisms like bacteria and plant leaf are introduced. In addition, the potential applications of the synthesized biomimetic nanostructures for colorimetry, fluorescence, surface plasmon resonance, surface-enhanced Raman scattering, electrical resistance, electrochemistry, and quartz crystal microbalance sensors are presented. This review will promote the understanding of relationships between biomolecules/microorganisms and functional nanomaterials in one way, and in another way it will guide the design and synthesis of biomimetic nanomaterials with unique properties in the future.

  16. Multimetallic nanosheets: synthesis and applications in fuel cells.

    Science.gov (United States)

    Zeb Gul Sial, Muhammad Aurang; Ud Din, Muhammad Aizaz; Wang, Xun

    2018-04-03

    Two-dimensional nanomaterials, particularly multimetallic nanosheets with single or few atoms thickness, are attracting extensive research attention because they display remarkable advantages over their bulk counterparts, including high electron mobility, unsaturated surface coordination, a high aspect ratio, and distinctive physical, chemical, and electronic properties. In particular, their ultrathin thickness endows them with ultrahigh specific surface areas and a relatively high surface energy, making them highly favorable for surface active applications; for example, they have great potential for a broad range of fuel cell applications. First, the state-of-the-art research on the synthesis of nanosheets with a controlled size, thickness, shape, and composition is described and special emphasis is placed on the rational design of multimetallic nanosheets. Then, a correlation is performed with the performance of multimetallic nanosheets with modified and improved electrochemical properties and high stability, including for the oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), formic acid oxidation (FAO), methanol oxidation reaction (MOR), ethanol oxidation reaction (EOR), and methanol tolerance are outlined. Finally, some perspectives and advantages offered by this class of materials are highlighted for the development of highly efficient fuel cell electrocatalysts, featuring low cost, enhanced performance, and high stability, which are the key factors for accelerating the commercialization of future promising fuel cells.

  17. The Advanced Aluminum Nitride Synthesis Methods and Its Applications: Patent Review.

    Science.gov (United States)

    Shishkin, Roman A; Elagin, Andrey A; Mayorova, Ekaterina S; Beketov, Askold R

    2016-01-01

    High purity nanosized aluminum nitride synthesis is a current issue for both industry and science. However, there is no up-to-date review considering the major issues and the technical solutions for different methods. This review aims to investigate the advanced methods of aluminum nitride synthesis and its development tendencies. Also the aluminum nitride application patents and prospects for development of the branch have been considered. The patent search on "aluminum nitride synthesis" has been carried out. The research activity has been analyzed. Special attention has been paid to the patenting geography and the leading researchers in aluminum nitride synthesis. Aluminum nitride synthesis methods have been divided into 6 main groups, the most studied approaches are carbothermal reduction (88 patents) and direct nitridation (107 patents). The current issues for each group have been analyzed; the main trends are purification of the final product and nanopowder synthesis. The leading researchers in aluminum nitride synthesis have represented 5 countries, namely: Japan, China, Russia, South Korea and USA. The main aluminum nitride application spheres are electronics (59,1 percent of applications) and new materials manufacturing (30,9 percent). The review deals with the state of the art data in nanosized aluminum nitride synthesis, the major issues and the technical solutions for different synthesis methods. It gives a full understanding of the development tendencies and of the current leaders in the sphere.

  18. Microfluidic Synthesis of Highly Potent Limit-size Lipid Nanoparticles for In Vivo Delivery of siRNA

    Directory of Open Access Journals (Sweden)

    Nathan M Belliveau

    2012-01-01

    Full Text Available Lipid nanoparticles (LNP are the leading systems for in vivo delivery of small interfering RNA (siRNA for therapeutic applications. Formulation of LNP siRNA systems requires rapid mixing of solutions containing cationic lipid with solutions containing siRNA. Current formulation procedures employ macroscopic mixing processes to produce systems 70-nm diameter or larger that have variable siRNA encapsulation efficiency, homogeneity, and reproducibility. Here, we show that microfluidic mixing techniques, which permit millisecond mixing at the nanoliter scale, can reproducibly generate limit size LNP siRNA systems 20 nm and larger with essentially complete encapsulation of siRNA over a wide range of conditions with polydispersity indexes as low as 0.02. Optimized LNP siRNA systems produced by microfluidic mixing achieved 50% target gene silencing in hepatocytes at a dose level of 10 µg/kg siRNA in mice. We anticipate that microfluidic mixing, a precisely controlled and readily scalable technique, will become the preferred method for formulation of LNP siRNA delivery systems.

  19. Synthesis and Applications of Inorganic/Organic-Polymer Nanocomposites

    Science.gov (United States)

    Goyal, Anubha

    This research work focuses on developing new synthesis routes to fabricate polymer nanocomposites tailored towards different applications. A simple, one-step method has been devised for synthesizing free-standing, flexible metal nanoparticle-polydimethylsiloxane films. This process simplifies prevalent methods to synthesize nanocomposites, in that here nanoparticles are created in situ while curing the polymer. This route circumvents the need for pre-synthesized nanoparticles, external reducing agents and stabilizers, thereby significantly reducing processing time and cost. The resulting nanocomposite also demonstrates enhancement in mechanical and antibacterial properties, with other envisaged applications in biomedical devices and catalysis. Applying the same mechanism as that used for the formation of bulk metalsiloxane nanocomposites, metal core-siloxane shell nanoparticles and siloxane nanowires were synthesized, with octadecylsilane as the precursor and in situ formed metal nanoparticles (gold, silver) as the catalyst. This method offers some unique advantages over the previously existing methods. This is a room temperature route which does not require high temperature refluxing or the use of pre-synthesized nanoparticles. Furthermore, this synthesis process gives a control over the shape of resulting nanocomposite structures (1-D wires or 0-D spherical particles). High thermal stability of polydimethylsiloxane (PDMS) makes it viable to alternatively synthesize metal nanoparticles in the polymer matrix by thermal decomposition process. This technique is generic across a range of metals (palladium, iron, nickel) and results in nanoparticles with a very narrow size distribution. Membranes with palladium nanoparticles demonstrate catalytic activity in ethylene hydrogenation reaction. Additionally, a new nanocomposite electrode has been developed for flexible and light-weight Li-ion batteries. Flexible films were prepared by the integration of the poly

  20. Design, synthesis and evaluation of VEGF-siRNA/CRS as a novel vector for gene delivery

    Directory of Open Access Journals (Sweden)

    Zhao W

    2016-11-01

    Full Text Available Wen Zhao, Yifan Zhang, Xueyun Jiang, Chunying Cui School of Chemical Biology and Pharmaceutical Sciences, Capital Medical University, Beijing, China Abstract: Small interfering RNA (siRNA delivery is a prospective method in gene therapy, but it has application limitations such as negative charge, water solubility and high molecular weight. In this study, a safe and efficient nano-vector, CRS, was designed and synthesized to facilitate siRNA delivery. Physical and chemical properties of VEGF-siRNA/CRS were characterized by methods including scanning electron microscopy (SEM, transmission electron microscopy, zeta potential (ζ measurement, drug-releasing rate measurement, gel electrophoresis and confocal microscopy. The biological activities were evaluated using cell viability assay, gene-silencing efficacy assay in vitro, real-time polymerase chain reaction, enzyme-linked immunosorbent assay (ELISA and antitumor tests in vivo. The mean nanoparticle size of VEGF-siRNA/CRS was 121.4±0.3 nm with positive ζ potential of 7.69±4.47 mV. The release rate of VEGF-siRNA from VEGF-siRNA/CRS was 82.50% sustained for 48 h in Tris-ethylenediaminetetraacetic acid buffer (pH 8.0. Real-time polymerase chain reaction was used to analyze the efficiency of the transfection, and the result showed that VEGF mRNA expression had been knocked down by 82.36%. The expression of VEGF protein was also recorded to be downregulated to 14.83% using ELISA. The results of cytotoxicity measured by Cell Counting Kit-8 assay showed that VEGF-siRNA/CRS had significant inhibitory effect on HeLa cells. The results of antitumor assays indicated that VEGF-siRNA/CRS exhibited tumor cell growth inhibition in vivo. The results demonstrated that VEGF-siRNA could be delivered and transported by the designed carrier, while siRNA could be released constantly and led to an increasing gene-silencing effect against VEGF gene. In conclusion, VEGF-siRNA/CRS is a promising carrier for si

  1. Application of drug delivery system for boron neutron capture therapy. Basic research toward clinical application

    International Nuclear Information System (INIS)

    Yanagie, Hironobu; Takahashi, Hiroyuki

    2010-01-01

    Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between 10 B and thermal neutrons ( 10 B+ 1 n → 7 Li+ 4 He (α) +2.31 MeV (93.7%)/2.79 MeV (6.3%)). The resulting lithium ions and αparticles are high linear energy transfer (LET) particles which give high biological effect. Their short range in tissue (5-9 μm) restricts radiation damage to those cells in which boron atoms are located at the time of neutron irradiation. BNCT has been applied clinically for the treatment of malignant brain tumors, malignant melanoma, head and neck cancer and hepatoma etc, recently. Sodium borocaptate (Na 2 10 B 12 H 11 SH; BSH) and borono-phenylalanine ( 10 BPA) are currently being used in clinical treatments. To achieve the selective delivery of boron atoms to cancer cells, drug delivery system (DDS) becomes an attractive intelligent technology as targeting and controlled release of drugs. We have firstly reported that 10 B atoms delivered by immunoliposomes are cytotoxic to human pancreatic carcinoma cells (AsPC-1) after thermal neutron irradiation in vitro. The intra-tumoural injection of boronated immunoliposomes can increase the retention of 10 B atoms in tumour cells, causing suppression of tumour growth in vivo following thermal neutron irradiation. We prepared polyethylene-glycol binding liposomes (PEG-liposomes) as an effective 10 B carrier to obviate phagocytosis by reticuloendotherial systems. We had prepared 10 BSH entrapped Water-in-Oil-in-Water (WOW) emulsion. The 10 B concentration in VX-2 tumour after intra-arterial injection of 10 BSH entrapped WOW emulsion was superior to the groups of 10 BSH entrapped conventional Lipiodol mix emulsion. 10 Boron entrapped WOW emulsion is one of the most useful for intra-arterial boron delivery carrier on BNCT to hepatocellular carcinoma. (author)

  2. Nanomedicine: towards development of patient-friendly drug-delivery systems for oncological applications

    Directory of Open Access Journals (Sweden)

    Ranganathan R

    2012-02-01

    Full Text Available Ramya Ranganathan1,*, Shruthilaya Madanmohan1,*, Akila Kesavan1, Ganga Baskar1, Yoganathan Ramia Krishnamoorthy2, Roy Santosham3, D Ponraju4, Suresh Kumar Rayala2, Ganesh Venkatraman1 1Department of Human Genetics, Sri Ramachandra University, Porur, 2Department of Biotechnology, Indian Institute of Technology, Madras, 3Department of Radiology and Imaging Sciences, Sri Ramachandra University, Porur, Chennai, 4Safety Engineering Division, Nuclear and Engineering Safety Group, Indira Gandhi Center for Atomic Research, Kalpakkam, India*Authors contributed equally to this workAbstract: The focus on nanotechnology in cancer treatment and diagnosis has intensified due to the serious side effects caused by anticancer agents as a result of their cytotoxic actions on normal cells. This nonspecific action of chemotherapy has awakened a need for formulations capable of definitive targeting with enhanced tumor-killing. Nanooncology, the application of nanobiotechnology to the management of cancer, is currently the most important area of nanomedicine. Currently several nanomaterial-based drug-delivery systems are in vogue and several others are in various stages of development. Tumor-targeted drug-delivery systems are envisioned as magic bullets for cancer therapy and several groups are working globally for development of robust systems.Keywords: patient-friendly, drug-delivery systems, cancer, nanomedicine

  3. A review of integrating electroactive polymers as responsive systems for specialized drug delivery applications.

    Science.gov (United States)

    Pillay, Viness; Tsai, Tong-Sheng; Choonara, Yahya E; du Toit, Lisa C; Kumar, Pradeep; Modi, Girish; Naidoo, Dinesh; Tomar, Lomas K; Tyagi, Charu; Ndesendo, Valence M K

    2014-06-01

    Electroactive polymers (EAPs) are promising candidate materials for the design of drug delivery technologies, especially in conditions where an "on-off" drug release mechanism is required. To achieve this, EAPs such as polyaniline, polypyrrole, polythiophene, ethylene vinyl acetate, and polyethylene may be blended into responsive hydrogels in conjunction with the desired drug to obtain a patient-controlled drug release system. The "on-off" drug release mechanism can be achieved through the environmental-responsive nature of the interpenetrating hydrogel-EAP complex via (i) charged ions initiated diffusion of drug molecules; (ii) conformational changes that occur during redox switching of EAPs; or (iii) electroerosion. These release mechanisms are not exhaustive and new release mechanisms are still under investigation. Therefore, this review seeks to provide a concise incursion and critical overview of EAPs and responsive hydrogels as a strategy for advanced drug delivery, for example, controlled release of neurotransmitters, sulfosalicyclic acid from cross-linked hydrogel, and vaccine delivery. The review further discusses techniques such as linear sweep voltammetry, cyclic voltammetry, impedance spectroscopy, and chronoamperometry for the determination of the redox capability of EAPs. The future implications of the hydrogel-EAP composites include, but not limited to, application toward biosensors, DNA hybridizations, microsurgical tools, and miniature bioreactors and may be utilized to their full potential in the form of injectable devices as nanorobots or nanobiosensors. Copyright © 2013 Wiley Periodicals, Inc.

  4. Application of an access technology delivery protocol to two children with cerebral palsy.

    Science.gov (United States)

    Mumford, Leslie; Chau, Tom

    2015-07-14

    This study further delineates the merits and limitations of the Access Technology Delivery Protocol (ATDP) through its application to two children with severe disabilities. We conducted mixed methods case studies to demonstrate the ATDP with two children with no reliable means of access to an external device. Evaluations of response efficiency, satisfaction, goal attainment, technology use and participation were made after 8 and 16 weeks of training with custom access technologies. After 16 weeks, one child's switch offered improved response efficiency, high teacher satisfaction and increased participation. The other child's switch resulted in improved satisfaction and switch effectiveness but lower overall efficiency. The latter child was no longer using his switch by the end of the study. These contrasting findings indicate that changes to any contextual factors that may impact the user's switch performance should mandate a reassessment of the access pathway. Secondly, it is important to ensure that individuals who will be responsible for switch training be identified at the outset and engaged throughout the ATDP. Finally, the ATDP should continue to be tested with individuals with severe disabilities to build an evidence base for the delivery of response efficient access solutions. Implications for Rehabilitation A data-driven, comprehensive access technology delivery protocol for children with complex communication needs could help to mitigate technology abandonment. Successful adoption of an access technology requires personalized design, training of the technology user, the teaching staff, the caregivers and other communication partners, and integration with functional activities.

  5. Micro- and nano bio-based delivery systems for food applications: In vitro behavior.

    Science.gov (United States)

    de Souza Simões, Lívia; Madalena, Daniel A; Pinheiro, Ana C; Teixeira, José A; Vicente, António A; Ramos, Óscar L

    2017-05-01

    Micro- and nanoencapsulation is an emerging technology in the food field that potentially allows the improvement of food quality and human health. Bio-based delivery systems of bioactive compounds have a wide variety of morphologies that influence their stability and functional performance. The incorporation of bioactive compounds in food products using micro- and nano-delivery systems may offer extra health benefits, beyond basic nutrition, once their encapsulation may provide protection against undesired environmental conditions (e.g., heat, light and oxygen) along the food chain (including processing and storage), thus improving their bioavailability, while enabling their controlled release and target delivery. This review provides an overview of the bio-based materials currently used for encapsulation of bioactive compounds intended for food applications, as well as the main production techniques employed in the development of micro- and nanosystems. The behavior of such systems and of bioactive compounds entrapped into, throughout in vitro gastrointestinal systems, is also tracked in a critical manner. Comparisons between various in vitro digestion systems (including the main advantages and disadvantages) currently in use, as well as correlations between the behavior of micro- and nanosystems studied through in vitro and in vivo systems were highlighted and discussed here for the first time. Finally, examples of bioactive micro- and nanosystems added to food simulants or to real food matrices are provided, together with a revision of the main challenges for their safe commercialization, the regulatory issues involved and the main legislation aspects. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Synthesis and Characterization of Mg-doped ZnO Nanorods for Biomedical Applications

    Science.gov (United States)

    Gemar, H.; Das, N. C.; Wanekaya, A.; Delong, R.; Ghosh, K.

    2013-03-01

    Nanomaterials research has become a major attraction in the field of advanced materials research in the area of Physics, Chemistry, and Materials Science. Bio-compatible and chemically stable metal nanoparticles have biomedical applications that includes drug delivery, cell and DNA separation, gene cloning, magnetic resonance imaging (MRI). This research is aimed at the fabrication and characterization of Mg-doped ZnO nanorods. Hydrothermal synthesis of undoped ZnO and Mg-doped ZnO nanorods is carried out using aqueous solutions of Zn(NO3)2 .6H2O, MgSO4, and using NH4OH as hydrolytic catalyst. Nanomaterials of different sizes and shapes were synthesized by varying the process parameters such as molarity (0.15M, 0.3M, 0.5M) and pH (8-11) of the precursors, growth temperature (130°C), and annealing time during the hydrothermal Process. Structural, morphological, and optical properties are studied using various techniques such as XRD, SEM, UV-vis and PL spectroscopy. Detailed structural, and optical properties will be discussed in this presentation. This work is partially supported by National Cancer Institute (1 R15 CA139390-01).

  7. Sonochemical synthesis of manganese (II) hydroxide for supercapacitor applications

    International Nuclear Information System (INIS)

    Anandan, Sambandam; Gnana Sundara Raj, Balasubramaniam; Lee, Gang-Juan; Wu, Jerry J.

    2013-01-01

    Graphical abstract: - Highlights: • Octahedral Mn(OH) 2 nanoparticles were prepared by sonochemical process. • TEM images indicates the formation of octahedral Mn(OH) 2 nanoparticles. • Octahedral Mn(OH) 2 nanoparticles are evaluated as a supercapacitor material. - Abstract: In this research, a rapid and controllable synthesis of octahedral Mn(OH) 2 nanoparticles with a size range from 140 to 200 nm has been done by a sonochemial irradiation method for the energy storage applications. Transmission electron microscopic images, energy disperse X-ray spectroscopy (EDX), X-ray photo electron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) analyses clearly indicate the formation of octahedral Mn(OH) 2 nanoparticles. Octahedral Mn(OH) 2 nanoparticles were evaluated as a supercapacitor material that exhibits specific capacitance 127 F g −1 at a current density of 0.5 mA cm −2 in the potential range from −0.1 to 0.8 V in 1 M Na 2 SO 4 solution

  8. Synthesis and Characterization of Metal Phosphates for Photocatalytic Applications

    KAUST Repository

    Al-Sabban, Bedour

    2012-07-01

    Solar energy is the most abundant efficient and important source of renewable energy. The objective of this study is to develop highly efficient visible light responsive photocatalysts for overall water splitting. This is done by using silver or copper containing materials. Phosphate compounds have caught much attention due to their rigid structure, thermal stability and resistance to chemical attacks. Solid phosphates can be prepared by direct solid-state reaction between metal cations and phosphate anions at high temperatures. Double metal phosphates of the Nasion-type structure had shown further technological importance. It has been reported that well-crystallized double metal phosphate particles have excellent ordering and cationic conduction channels in the Nasicon framework. In this study, several Nasion-type structured materials have been synthesized by solid-state method (e.g. CuTi2(PO4)3 and AgTi2(PO4)3) heated up under different temperatures (400–1100C) in N2 or air atmosphere. These materials were characterized by XRD, SEM, DR-UV-Vis spectroscopy and tested for photocatalytic applications. A new method for direct synthesis of photoelectrode on Ti Plate had been demonstrated. Further investigations on controlling the size and morphology for better performance of single and double metal phosphates will be done.

  9. Fluorine-18-labelled molecules: synthesis and application in medical imaging

    International Nuclear Information System (INIS)

    Dolle, F.; Perrio, C.; Barre, L.; Lasne, M.C.; Le Bars, D.

    2006-01-01

    Positron emission tomography (PET) is one of the more powerful available techniques for medical imaging. It relies on the use of molecules labelled with a positron emitter (β + ). Among those emitters, fluorine-18, available from a cyclotron, is a radionuclide of choice because of its relatively long-half-life (109.8 min) and the relatively low energy of the emitted-positron. The electrophilic form of fluorine-18 ([ 18 F]F 2 or reagents derived from [ 18 F]F 2 ) is mainly used for hydrogen or metal substitutions on aromatic or vinylic carbons. The presence of the stable isotope (fluorine-19) in the radiotracers limits their use in medical imaging. The nucleophilic form of fluorine-18 (alkaline mono-fluoride, K[ 18 F]F, the most used), obtained from irradiation of enriched water, is widely used in aliphatic and (hetero)aromatic substitutions for the synthesis of radiotracers with high specific radioactivity. Some examples of radio-fluorinated tracers used in PET are presented, as well as some of their in vivo applications in human. (authors)

  10. Silver nanoparticles: synthesis, properties, toxicology, applications and perspectives

    International Nuclear Information System (INIS)

    Tran, Quang Huy; Nguyen, Van Quy; Le, Anh-Tuan

    2013-01-01

    In recent years the outbreak of re-emerging and emerging infectious diseases has been a significant burden on global economies and public health. The growth of population and urbanization along with poor water supply and environmental hygiene are the main reasons for the increase in outbreak of infectious pathogens. Transmission of infectious pathogens to the community has caused outbreaks of diseases such as influenza (A/H 5 N 1 ), diarrhea (Escherichia coli), cholera (Vibrio cholera), etc throughout the world. The comprehensive treatments of environments containing infectious pathogens using advanced disinfectant nanomaterials have been proposed for prevention of the outbreaks. Among these nanomaterials, silver nanoparticles (Ag-NPs) with unique properties of high antimicrobial activity have attracted much interest from scientists and technologists to develop nanosilver-based disinfectant products. This article aims to review the synthesis routes and antimicrobial effects of Ag-NPs against various pathogens including bacteria, fungi and virus. Toxicology considerations of Ag-NPs to humans and ecology are discussed in detail. Some current applications of Ag-NPs in water-, air- and surface- disinfection are described. Finally, future prospects of Ag-NPs for treatment and prevention of currently emerging infections are discussed. (review)

  11. Silver nanoparticles: synthesis, properties, toxicology, applications and perspectives

    Science.gov (United States)

    Tran, Quang Huy; Quy Nguyen, Van; Le, Anh-Tuan

    2013-09-01

    In recent years the outbreak of re-emerging and emerging infectious diseases has been a significant burden on global economies and public health. The growth of population and urbanization along with poor water supply and environmental hygiene are the main reasons for the increase in outbreak of infectious pathogens. Transmission of infectious pathogens to the community has caused outbreaks of diseases such as influenza (A/H5N1), diarrhea (Escherichia coli), cholera (Vibrio cholera), etc throughout the world. The comprehensive treatments of environments containing infectious pathogens using advanced disinfectant nanomaterials have been proposed for prevention of the outbreaks. Among these nanomaterials, silver nanoparticles (Ag-NPs) with unique properties of high antimicrobial activity have attracted much interest from scientists and technologists to develop nanosilver-based disinfectant products. This article aims to review the synthesis routes and antimicrobial effects of Ag-NPs against various pathogens including bacteria, fungi and virus. Toxicology considerations of Ag-NPs to humans and ecology are discussed in detail. Some current applications of Ag-NPs in water-, air- and surface- disinfection are described. Finally, future prospects of Ag-NPs for treatment and prevention of currently emerging infections are discussed.

  12. Application of methods of discrete mathematics at modular synthesis of mechatronic devices

    OpenAIRE

    Nikiforov, S.; Nikiforov, B.; Mandarov, E.; Rabdanova, N.

    2010-01-01

    The article is devoted to application of methods of discrete mathematics (the theory of counts, the method of matrix code and others) and synthesis of executive mechanisms of mechatronic handling devices

  13. Tritium labelled steroids, preparation process and application to synthesis of tritium labelled estrane derivatives

    International Nuclear Information System (INIS)

    1978-01-01

    Process for preparing new steroids labelled with tritium in 6.7 and comprising in 3 a blocked ketonic group as ketal, thioketal or derivatives. Application of these products to the synthesis of tritium labelled estrane derivatives [fr

  14. Synthesis, Characterization and Application of Multiscale Porous Materials

    Energy Technology Data Exchange (ETDEWEB)

    Hussami, Linda

    2010-07-01

    This thesis work brings fresh insights and improved understanding of nano scale materials through introducing new hybrid composites, 2D hexagonal in MCM-41 and 3D random interconnected structures of different materials, and application relevance for developing fields of science, such as fuel cells and solar cells. New types of porous materials and organometallic crystals have been prepared and characterized in detail. The porous materials have been used in several studies: as hosts to encapsulate metal-organic complexes; as catalyst supports and electrode materials in devices for alternative energy production. The utility of the new porous materials arises from their unique structural and surface chemical characteristics as demonstrated here using various experimental and theoretical approaches. New single crystal structures and arene-ligand exchange properties of f-block elements coordinated to ligand arene and halogallates are described in Paper I. These compounds have been incorporated into ordered 2D-hexagonal MCM-41 and polyhedral silica nano foam (PNF-SiO{sub 2}) matrices without significant change to the original porous architectures as described in Paper II and III. The resulting inorganic/organic hybrids exhibited enhanced luminescence activity relative to the pure crystalline complexes. A series of novel polyhedral carbon nano foams (PNF-C's) and inverse foams were prepared by nano casting from PNF-SiO{sub 2}'s. These are discussed in Paper IV. The synthesis conditions of PNF-C's were systematically varied as a function of the filling ratio of carbon precursor and their structures compared using various characterization methods. The carbonaceous porous materials were further tested in Paper V and VI as possible catalysts and catalyst supports in counter- and working electrodes for solar- and fuel cell applications

  15. Synthesis of Conductive Polymeric Nanocomposites for Applications in Responsive Materials

    Science.gov (United States)

    Chavez, Jessica

    concentration as well as the extension of the reaction time. The overall interaction between the conductive polymer and the commercial fibers showed that the conductive polymer was physically adsorbed to the commercial fiber. This physical adsorption caused a decrease in conductive efficiency as a function of repeated washes because the weak intermolecular forces between the conductive polymer and the commercial fiber. This led to the synthesis of conductive films and nanofibers by integrating the conductive polymers directly into a cellulose acetate matrix. The voltage efficiency of the conductive films was lower compared to the coated commercial fiber nanocomposites. However, the conductive material generated greater lux values compared to the coated commercial fiber nanocomposites. Theses conductive materials can be applied to applications in both the medical field and water filtration. The conductive films can be used to create a sensor based system that can trigger a sensor to signify when bandages used for wound management need to be changed. The conductive nanofibers can be used in water filtration as a means of electroplating metals ions from contaminated water. Overall, the synthesis of these conductive materials can be applicable for responsive materials.

  16. Mesoporous Silica and Organosilica Nanoparticles: Physical Chemistry, Biosafety, Delivery Strategies, and Biomedical Applications

    KAUST Repository

    Croissant, Jonas G.

    2017-11-30

    Predetermining the physico-chemical properties, biosafety, and stimuli-responsiveness of nanomaterials in biological environments is essential for safe and effective biomedical applications. At the forefront of biomedical research, mesoporous silica nanoparticles and mesoporous organosilica nanoparticles are increasingly investigated to predict their biological outcome by materials design. In this review, it is first chronicled that how the nanomaterial design of pure silica, partially hybridized organosilica, and fully hybridized organosilica (periodic mesoporous organosilicas) governs not only the physico-chemical properties but also the biosafety of the nanoparticles. The impact of the hybridization on the biocompatibility, protein corona, biodistribution, biodegradability, and clearance of the silica-based particles is described. Then, the influence of the surface engineering, the framework hybridization, as well as the morphology of the particles, on the ability to load and controllably deliver drugs under internal biological stimuli (e.g., pH, redox, enzymes) and external noninvasive stimuli (e.g., light, magnetic, ultrasound) are presented. To conclude, trends in the biomedical applications of silica and organosilica nanovectors are delineated, such as unconventional bioimaging techniques, large cargo delivery, combination therapy, gaseous molecule delivery, antimicrobial protection, and Alzheimer\\'s disease therapy.

  17. Stimulus-responsive liposomes as smart nanoplatforms for drug delivery applications.

    Science.gov (United States)

    Zangabad, Parham Sahandi; Mirkiani, Soroush; Shahsavari, Shayan; Masoudi, Behrad; Masroor, Maryam; Hamed, Hamid; Jafari, Zahra; Taghipour, Yasamin Davatgaran; Hashemi, Hura; Karimi, Mahdi; Hamblin, Michael R

    2018-02-01

    Liposomes are known to be promising nanoparticles (NPs) for drug delivery applications. Among different types of self-assembled NPs, liposomes stand out for their non-toxic nature, and their possession of dual hydrophilic-hydrophobic domains. Advantages of liposomes include the ability to solubilize hydrophobic drugs, the ability to incorporate different hydrophilic and lipophilic drugs at the same time, lessening the exposure of host organs to potentially toxic drugs and allowing modification of the surface by a variety of different chemical groups. This modification of the surface, or of the individual constituents, may be used to achieve two important goals. Firstly, ligands for active targeting can be attached that are recognized by cognate receptors over-expressed on the target cells of tissues. Secondly, modification can be used to impart a stimulus-responsive or "smart" character to the liposomes, whereby the cargo is released on demand only when certain internal stimuli (pH, reducing agents, specific enzymes) or external stimuli (light, magnetic field or ultrasound) are present. Here, we review the field of smart liposomes for drug delivery applications.

  18. Synthesis of Biochemical Applications on Digital Microfluidic Biochips with Operation Execution Time Variability

    DEFF Research Database (Denmark)

    Alistar, Mirela; Pop, Paul

    2015-01-01

    that each biochemical operation in an application is characterized by a worst-case execution time (wcet). However, during the execution of the application, due to variability and randomness in biochemical reactions, operations may finish earlier than their wcetswcets, resulting in unexploited slack...... in the schedule. In this paper, we first propose an online synthesis strategy that re-synthesizes the application at runtime when operations experience variability in their execution time, exploiting thus the slack to obtain shorter application completion times. We also propose a quasi-static synthesis strategy...... approaches have been proposed for the synthesis of digital microfluidic biochips, which, starting from a biochemical application and a given biochip architecture, determine the allocation, resource binding, scheduling, placement and routing of the operations in the application. Researchers have assumed...

  19. Green synthesis of water soluble semiconductor nanocrystals and their applications

    Science.gov (United States)

    Wang, Ying

    II-VI semiconductor nanomaterials, e.g. CdSe and CdTe, have attracted great attention over the past decades due to their fascinating optical and electrical properties. The research presented here focuses on aqueous semiconductor nanomaterials. The work can be generally divided into three parts: synthesis, property study and application. The synthetic work is devoted to develop new methods to prepare shape- and structure-controlled II-VI semiconductor nanocrystals including nanoparticles and nanowires. CdSe and CdSe CdS semiconductor nanocrystals have been synthesized using sodium citrate as a stabilizer. Upon prolonged illumination with visible light, photoluminescence quantum yield of those quantum dots can be enhanced up to 5000%. The primary reason for luminescence enhancement is considered to be the removing of specific surface states (photocorrosion) and the smoothing of the CdSe core surface (photoannealing). CdTe nanowires are prepared through self-organization of stabilizer-depleted CdTe nanoparticles. The dipolar-dipolar attraction is believed to be the driving force of nanowire formation. The rich surface chemistry of CdTe nanowire is reflected by the formation of silica shell with different morphologies when nanowires with different capping ligands are used. Te and Se nanowires are prepared by chemical decomposition of CdTe and CdSe nanoparticles in presence of an external chemical stimulus, EDTA. These results not only provide a new example of NP→NW transformation, but also lead to a better understanding of the molecular process occurring in the stabilizer-depleted nanoparticles. The applications of those semiconductor materials are primarily based on the construction of nano-structured ultrathin films with desirable functions by using layer-by-layer technique (LBL). We demonstrate that light-induced micro-scale multicolor luminescent patterns can be obtained on photoactivable CdSe/CdS nanoparticles thin films by combining the advantages of LBL as

  20. Virosome, a hybrid vehicle for efficient and safe drug delivery and its emerging application in cancer treatment.

    Science.gov (United States)

    Liu, Hanqing; Tu, Zhigang; Feng, Fan; Shi, Haifeng; Chen, Keping; Xu, Ximing

    2015-06-01

    A virosome is an innovative hybrid drug delivery system with advantages of both viral and non-viral vectors. Studies have shown that a virosome can carry various biologically active molecules, such as nucleic acids, peptides, proteins and small organic molecules. Targeted drug delivery using virosome-based systems can be achieved through surface modifications of virosomes. A number of virosome-based prophylactic and therapeutic products with high safety profiles are currently available in the market. Cancer treatment is a big battlefield for virosome-based drug delivery systems. This review provides an overview of the general concept, preparation procedures, working mechanisms, preclinical studies and clinical applications of virosomes in cancer treatment.

  1. Synthesis, thermal properties and applications of polymer-clay nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Meneghetti, Paulo [Chemical Engineering Department, Case Western Reserve University, 10900 Euclid Ave. Cleveland, OH 44106 (United States); Qutubuddin, Syed [Chemical Engineering Department, Case Western Reserve University, 10900 Euclid Ave. Cleveland, OH 44106 (United States)]. E-mail: sxq@case.edu

    2006-03-15

    Polymer-clay nanocomposites constitute a new class of materials in which the polymer matrix is reinforced by uniformly dispersed inorganic particles (usually 10 wt.% or less) having at least one dimension in the nanometer scale. Nanocomposites exhibit improved properties when compared to pure polymer or conventional composites, such as enhanced mechanical and thermal properties, reduced gas permeability, and improved chemical stability. In this work, the synthesis of poly(methyl methacrylate) (PMMA)/clay nanocomposites is described via two methods: in situ and emulsion polymerization. The in situ technique follows a two-step process: ion-exchange of the clay to make it hydrophobic, and polymerization after dispersing the functionalized clay in the monomer. The emulsion technique combines the two steps of the in situ method into one by conducting ion-exchange and polymerization in an aqueous medium in the same reactor. The clay (montmorillonite, MMT) is functionalized with a zwitterionic surfactant, octadecyl-dimethyl betaine (C18DMB). Partially exfoliated nanocomposite, observed by transmission electron microscopy (TEM), was obtained by emulsion polymerization with 10 wt.% clay. Glass transition temperature (T {sub g}) of this nanocomposite was 18 deg. C higher than pure PMMA. With the same clay content, in situ polymerization produced intercalated nanocomposite with T {sub g} 10 deg. C lower than the emulsion nanocomposite. The storage modulus of partially exfoliated nanocomposite was superior to the intercalated structure and to the pure polymer. Using nanocomposite technology, novel PMMA nanocomposite gel electrolytes were synthesized exhibiting improved ionic conductivity and stable lithium interfacial resistance. Nanocomposites can also be used for gas storage and packaging applications as demonstrated by high barrier polymer-clay films.

  2. Synthesis, thermal properties and applications of polymer-clay nanocomposites

    International Nuclear Information System (INIS)

    Meneghetti, Paulo; Qutubuddin, Syed

    2006-01-01

    Polymer-clay nanocomposites constitute a new class of materials in which the polymer matrix is reinforced by uniformly dispersed inorganic particles (usually 10 wt.% or less) having at least one dimension in the nanometer scale. Nanocomposites exhibit improved properties when compared to pure polymer or conventional composites, such as enhanced mechanical and thermal properties, reduced gas permeability, and improved chemical stability. In this work, the synthesis of poly(methyl methacrylate) (PMMA)/clay nanocomposites is described via two methods: in situ and emulsion polymerization. The in situ technique follows a two-step process: ion-exchange of the clay to make it hydrophobic, and polymerization after dispersing the functionalized clay in the monomer. The emulsion technique combines the two steps of the in situ method into one by conducting ion-exchange and polymerization in an aqueous medium in the same reactor. The clay (montmorillonite, MMT) is functionalized with a zwitterionic surfactant, octadecyl-dimethyl betaine (C18DMB). Partially exfoliated nanocomposite, observed by transmission electron microscopy (TEM), was obtained by emulsion polymerization with 10 wt.% clay. Glass transition temperature (T g ) of this nanocomposite was 18 deg. C higher than pure PMMA. With the same clay content, in situ polymerization produced intercalated nanocomposite with T g 10 deg. C lower than the emulsion nanocomposite. The storage modulus of partially exfoliated nanocomposite was superior to the intercalated structure and to the pure polymer. Using nanocomposite technology, novel PMMA nanocomposite gel electrolytes were synthesized exhibiting improved ionic conductivity and stable lithium interfacial resistance. Nanocomposites can also be used for gas storage and packaging applications as demonstrated by high barrier polymer-clay films

  3. Synthesis of New Vinyl Monomers for Chemical Agent Sensing Applications

    National Research Council Canada - National Science Library

    Hogen-Esch, Thieo

    2001-01-01

    The synthesis of styrene momomer p-vinylbenzoylacetophenone (monomer i) has been carried by the acetylation of 2- chloroethylbenzene and base elimination of the resulting 4-acetyl-2-chloroethylbenzene to give 4-acetylstyrene...

  4. Utilization of bio-degradable fermented tapioca to synthesized low toxicity of carbon nanotubes for drug delivery applications

    International Nuclear Information System (INIS)

    Nurulhuda, I.; Poh, R.; Mazatulikhma, M. Z.; Rusop, M.; Salman, A. H. A.; Haseeb, A. K.

    2016-01-01

    Carbon nanotubes (CNT) have potential biomedical applications, and investigations are shifting towards the production of such nanotubes using renewable natural sources. CNTs were synthesized at various temperatures of 700, 750, 800, 850 and 900 °C, respectively, using a local fermented food known as “tapai ubi” or fermented tapioca as a precursor. The liquid part of this fermented food was heated separately at 80°C and channeled directly into the furnace system that employs the thermal chemical vapor deposition (CVD) method. Ferrocene, which was the catalyst was placed in furnace 1 in the thermal CVD process. The resulting CNTs produced from the process were studied using field emission scanning electron microscopy (FESEM) and Raman spectroscopy. The FESEM images showed the growth morphology of the CNTs at the different temperatures employed. It was observed that the higher the synthesis temperature up to a point, the diameter of CNTs produced, after which the diameter increased. CNTs with helical structures were observed at 700 °C with a diameter range of 111 - 143 nm. A more straightened structure was observed at 750 °C with a diameter range of 59 - 121 nm. From 800 °C onwards, the diameters of the CNTs were less than 60 nm. Raman analysis revealed the present of D, G and G’ peak were observed at 1227-1358, 1565-1582, and 2678-2695 cm −1 , respectively. The highest degree of crystallity of the carbon nanotubes synthesized were obtained at 800 °C. The radial breathing mode (RBM) were in range between 212-220 and 279-292 cm −1 . Carbon nanotubes also being functionalized with Polyethylene bis(amine) Mw2000 (PEG 2000-NH2) and showed highly cells viability compared to non-functionalized CNT. The nanotubes synthesized will be applied as drug delivery in future study.

  5. Utilization of bio-degradable fermented tapioca to synthesized low toxicity of carbon nanotubes for drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Nurulhuda, I., E-mail: nurulnye@gmail.com [NANO-SciTech Centre, Institute of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Poh, R. [Department of Molecular Medicine, University of Malaya, 50603 Kuala Lumpur (Malaysia); Mazatulikhma, M. Z. [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Rusop, M., E-mail: nanouitm@gmail.com [NANO-Electronic Centre, Faculty of Electrical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Salman, A. H. A.; Haseeb, A. K.

    2016-07-06

    Carbon nanotubes (CNT) have potential biomedical applications, and investigations are shifting towards the production of such nanotubes using renewable natural sources. CNTs were synthesized at various temperatures of 700, 750, 800, 850 and 900 °C, respectively, using a local fermented food known as “tapai ubi” or fermented tapioca as a precursor. The liquid part of this fermented food was heated separately at 80°C and channeled directly into the furnace system that employs the thermal chemical vapor deposition (CVD) method. Ferrocene, which was the catalyst was placed in furnace 1 in the thermal CVD process. The resulting CNTs produced from the process were studied using field emission scanning electron microscopy (FESEM) and Raman spectroscopy. The FESEM images showed the growth morphology of the CNTs at the different temperatures employed. It was observed that the higher the synthesis temperature up to a point, the diameter of CNTs produced, after which the diameter increased. CNTs with helical structures were observed at 700 °C with a diameter range of 111 - 143 nm. A more straightened structure was observed at 750 °C with a diameter range of 59 - 121 nm. From 800 °C onwards, the diameters of the CNTs were less than 60 nm. Raman analysis revealed the present of D, G and G’ peak were observed at 1227-1358, 1565-1582, and 2678-2695 cm{sup −1}, respectively. The highest degree of crystallity of the carbon nanotubes synthesized were obtained at 800 °C. The radial breathing mode (RBM) were in range between 212-220 and 279-292 cm{sup −1}. Carbon nanotubes also being functionalized with Polyethylene bis(amine) Mw2000 (PEG 2000-NH2) and showed highly cells viability compared to non-functionalized CNT. The nanotubes synthesized will be applied as drug delivery in future study.

  6. Topical application of recombinant activated factor VII during cesarean delivery for placenta previa.

    Science.gov (United States)

    Schjoldager, Birgit T B G; Mikkelsen, Emmeli; Lykke, Malene R; Præst, Jørgen; Hvas, Anne-Mette; Heslet, Lars; Secher, Niels J; Salvig, Jannie D; Uldbjerg, Niels

    2017-06-01

    During cesarean delivery in patients with placenta previa, hemorrhaging after removal of the placenta is often challenging. In this condition, the extraordinarily high concentration of tissue factor at the placenta site may constitute a principle of treatment as it activates coagulation very effectively. The presumption, however, is that tissue factor is bound to activated factor VII. We hypothesized that topical application of recombinant activated factor VII at the placenta site reduces bleeding without affecting intravascular coagulation. We included 5 cases with planned cesarean delivery for placenta previa. After removal of the placenta, the surgeon applied a swab soaked in recombinant activated factor VII containing saline (1 mg in 246 mL) to the placenta site for 2 minutes; this treatment was repeated once if the bleeding did not decrease sufficiently. We documented the treatment on video recordings and measured blood loss. Furthermore, we determined hemoglobin concentration, platelet count, international normalized ratio, activated partial thrombin time, fibrinogen (functional), factor VII:clot, and thrombin generation in peripheral blood prior to and 15 minutes after removal of the placenta. We also tested these blood coagulation variables in 5 women with cesarean delivery planned for other reasons. Mann-Whitney test was used for unpaired data. In all 5 cases, the uterotomy was closed under practically dry conditions and the median blood loss was 490 (range 300-800) mL. There were no adverse effects of recombinant activated factor VII and we did not measure factor VII to enter the circulation. Neither did we observe changes in thrombin generation, fibrinogen, activated partial thrombin time, international normalized ratio, and platelet count in the peripheral circulation (all P values >.20). This study indicates that in patients with placenta previa, topical recombinant activated factor VII may diminish bleeding from the placenta site without initiation

  7. Synthesis of Amphiphilic Hyperbranched AIE-active Fluorescent Organic Nanoparticles and Their Application in Biological Application.

    Science.gov (United States)

    Lv, Qiulan; Wang, Ke; Xu, Dazhuang; Liu, Meiying; Wan, Qing; Huang, Hongye; Liang, Shangdong; Zhang, Xiaoyong; Wei, Yen

    2016-02-01

    Aggregation-induced emission (AIE) dyes have recently attracted much attention for biomedical applications for their remarkable AIE properties. However, the hydrophobic nature of AIE dyes made them difficult to be dispersed in physiological solution and problematic for biomedical application directly. Great efforts have been made to overcome this problem, and different strategies for preparation of water dispersible AIE based nanoprobes had been explored previously. However, a facile and effective strategy is still highly desirable and of great importance for the biomedical applications of AIE dye based on nanoprobes. In this work, the fabrication of amphiphilic hyperbranched fluorescent organic nanoparticles with a core-shell structure based on an AIE dye [tetraphenylethene acrylate (TPE-O-E)] and a hyperbranched polyamino compound [polyethylene imine (PEI)] through Michael addition reaction is described for the first time. The AIE dye as well as the final product PEI-TPE-O-E was characterized in detail by a number of techniques. To test their biomedical application potential, the cell viability as well as cell imaging properties of the PEI-TPE-O-E was also examined. The results showed that the PEI-TPE-O-E organic nanoparticles presented high water dispersiblity, ultrabright fluroerescence, low cytotoxicity and excellent biocompatibility, making them promising for biological imaging and gene delivery applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Anisotropic nanomaterials: Synthesis, optical and magnetic properties, and applications

    Science.gov (United States)

    Banholzer, Matthew John

    As nanoscience and nanotechnology mature, anisotropic metal nanostructures are emerging in a variety of contexts as valuable class of nanostructures due to their distinctive attributes. With unique properties ranging from optical to magnetic and beyond, these structures are useful in many new applications. Chapter two discusses the nanodisk code: a linear array of metal disk pairs that serve as surface-enhanced Raman scattering substrates. These multiplexing structures employ a binary encoding scheme, perform better than previous nanowires designs (in the context of SERS) and are useful for both convert encoding and tagging of substrates (based both on spatial disk position and spectroscopic response) as well as biomolecule detection (e.g. DNA). Chapter three describes the development of improved, silver-based nanodisk code structures. Work was undertaken to generate structures with high yield and reproducibility and to reoptimize the geometry of each disk pair for maximum Raman enhancement. The improved silver structures exhibit greater enhancement than Au structures (leading to lower DNA detection limits), convey additional flexibility, and enable trinary encoding schemes where far more unique structures can be created. Chapter four considers the effect of roughness on the plasmonic properties of nanorod structures and introduces a novel method to smooth the end-surfaces of nanorods structures. The smoothing technique is based upon a two-step process relying upon diffusion control during nanowires growth and selective oxidation after each step of synthesis is complete. Empirical and theoretical work show that smoothed nanostructures have superior and controllable optical properties. Chapter five concerns silica-encapsulated gold nanoprisms. This encapsulation allows these highly sensitive prisms to remain stable and protected in solution, enabling their use as class-leading sensors. Theoretical study complements the empirical work, exploring the effect of

  9. Structure-Processing-Property Relationship of Poly(Glycolic Acid) for Drug Delivery Systems 1: Synthesis and Catalysis

    OpenAIRE

    Singh, Vineet; Tiwari, Meena

    2010-01-01

    Till date, market is augmented with a huge number of improved drug delivery systems. The success in this area is basically due to biodegradable polymers. Although conventional systems of drug delivery utilizing the natural and semisynthetic polymers so long but synthetic polymer gains success in the controlled drug delivery area due to better degradation profile and controlled network and functionality. The polyesters are the most studied class group due the susceptible ester linkage in thei...

  10. Bioactivity of Hybrid Polymeric Magnetic Nanoparticles and Their Applications in Drug Delivery.

    Science.gov (United States)

    Mohammed, Leena; Ragab, Doaa; Gomaa, Hassan

    2016-01-01

    Engineered magnetic nanoparticles (MNPs) possess unique properties and hold great potential in biomedicine and clinical applications. With their magnetic properties and their ability to work at cellular and molecular level, MNP have been applied both in-vitro and in-vivo in targeted drug delivery and imaging. Focusing on Iron Oxide Superparamagnetic nanoparticles (SPIONs), this paper elaborates on the recent advances in development of hybrid polymeric-magnetic nanoparticles. Their main applications in drug delivery include Chemotherapeutics, Hyperthermia treatment, Radio-therapeutics, Gene delivary, and Biotheraputics. Physiochemical properties such as size, shape, surface and magnetic properties are key factors in determining their behavior. Additionally tailoring SPIONs surface is often vital for desired cell targetting and improved efficiency. Polymer coating is specifically reviewed with brief discussion of SPIONs administration routes. Commonly used drug release models for describing release mechanisms and the nanotoxicity aspects are also discussed. This review focus on superparamagnetic nanoparticles coated with different types of polymers starting with the key physiochemical features that dominate their behavior. The importance of surface modification is addressed. Subsequently, the major classes of polymer modified iron oxide nanoparticles is demonstrated according to their clinical use and application. Clinically approved nanoparticles are then addressed and the different routes of administration are mentioned. Lastly, mathematical models of drug release profile of the common used nanoparticles are addressed. MNPs emerging in recent medicine are remarkable for both imaging and therapeutics, particularly, as drug carriers for their great potential in targeted delivery and cancer treatment. Targeting ability and biocompatibility can be improved though surface coating which provides a mean to alter the surface features including physical characteristics and

  11. [Application of ultrasound-enhanced gene and drug delivery to the ocular tissue].

    Science.gov (United States)

    Sonoda, Shozo; Yamashita, Toshifumi; Suzuki, Ryo; Maruyama, Kazuo; Sakamoto, Taiji

    2013-01-01

    Visual images provide an immensely rich source of information about the external world. Eye has characteristic structure sensory cells are arranged along the eye wall, and is filled inside with vitreous body. In recent years, intravitreal injection of anti-vascular endothelial growth factor (VEGF) agent had widely spread, and numerous number of patients who suffered ocular angiogenic disease such as diabetic retinopathy, age-related macular degeneration and retinal vascular occlusion for the disease, were treated and spared the blindness. Vitreous cavity was regarded as reservoir of drug, intravitreal injection is thought a sort of drug delivery. However, with regard to the administration of a selective drug deliver, it has not yet been solved. Our aim is to establish a new method of gene transfer, drug delivery using low-energy ultrasound to the eye, to date, we confirmed drug and gene deliver to the ocular tissue such as cornea, conjunctiva and retina with high efficiency. In addition, tissue damage was minimal. We have also shown that ultrasound irradiation with combination of a microbubbles or bubble liposome could be introduced drug and gene more effectively. Based on these knowledge, we will focus on development of a new device for intraocular ultrasound exposure and potential for therapeutic application of ultrasound to humans retinal disease such as retinal artery obstruction.

  12. Local Antibiotic Delivery Systems: Current and Future Applications for Diabetic Foot Infections.

    Science.gov (United States)

    Markakis, Konstantinos; Faris, Alan Robert; Sharaf, Hamed; Faris, Barzo; Rees, Sharon; Bowling, Frank L

    2018-03-01

    Foot infections are common among diabetic patients with peripheral neuropathy and/or peripheral arterial disease, and it can be the pivotal event leading to a minor or major amputation of the lower extremity. Treatment of diabetic foot infections, especially deep-seated ones, remains challenging, in part because impaired blood perfusion and the presence of biofilms can impair the effectiveness of systemic antibiotics. The local application of antibiotics is an emerging field in the treatment of diabetic foot infections, with demonstrable advantages. These include delivery of high concentrations of antibiotics in the affected area, limited systemic absorption, and thus negligible side effects. Biodegradable vehicles, such as calcium sulfate beads, are the prototypical system, providing a good elution profile and the ability to be impregnated with a variety of antibiotics. These have largely superseded the nonbiodegradable vehicles, but the strongest evidence available is for calcium bead implantation for osteomyelitis management. Natural polymers, such as collagen sponge, are an emerging class of delivery systems, although thus far, data on diabetic foot infections are limited. There is recent interest in the novel antimicrobial peptide pexiganan in the form of cream, which is active against most of the microorganisms isolated in diabetic foot infections. These are promising developments, but randomized trials are required to ascertain the efficacy of these systems and to define the indications for their use. Currently, the role of topical antibiotic agents in treating diabetic foot infections is limited and outside of routine practice.

  13. Production methodologies of polymeric and hydrogel particles for drug delivery applications.

    Science.gov (United States)

    Lima, Ana Catarina; Sher, Praveen; Mano, João F

    2012-02-01

    Polymeric particles are ideal vehicles for controlled delivery applications due to their ability to encapsulate a variety of substances, namely low- and high-molecular mass therapeutics, antigens or DNA. Micro and nano scale spherical materials have been developed as carriers for therapies, using appropriated methodologies, in order to achieve a prolonged and controlled drug administration. This paper reviews the methodologies used for the production of polymeric micro/nanoparticles. Emulsions, phase separation, spray drying, ionic gelation, polyelectrolyte complexation and supercritical fluids precipitation are all widely used processes for polymeric micro/nanoencapsulation. This paper also discusses the recent developments and patents reported in this field. Other less conventional methodologies are also described, such as the use of superhydrophobic substrates to produce hydrogel and polymeric particulate biomaterials. Polymeric drug delivery systems have gained increased importance due to the need for improving the efficiency and versatility of existing therapies. This allows the development of innovative concepts that could create more efficient systems, which in turn may address many healthcare needs worldwide. The existing methods to produce polymeric release systems have some critical drawbacks, which compromise the efficiency of these techniques. Improvements and development of new methodologies could be achieved by using multidisciplinary approaches and tools taken from other subjects, including nanotechnologies, biomimetics, tissue engineering, polymer science or microfluidics.

  14. Polymeric biomaterials for nerve regeneration applications: From promoting cellular organization to the delivery of bioactive molecules

    Science.gov (United States)

    Delgado-Rivera, Roberto L.

    Thousands of new cases of injury to the central nervous system (CNS) occur each year in the USA and all over the world. However, despite recent advances, at present there is no cure for the resulting paraplegia or quadriplegia. This research is directed towards engineering biomaterial platforms to promote cellular organization at the surface of polymer scaffolds that will be conducive to proper regeneration of injured CNS. In addition, the formulation of a delivery system for neuroactive molecules using polymer-based materials will be evaluated to establish its potential to treat CNS disorders. Initial studies involved the chemical modification of an electrospun nonwoven matrix of nanofibers with fibroblast growth factor 2 (FGF-2). Nanofibers alone up-regulated FGF-2, albeit to a lesser extent than nanofibers covalently modified with FGF-2. These results underscore the importance of both surface topography and growth factor presentation on cellular function. Moreover, that FGF-2 modified nanofibrillar scaffolds may demonstrate utility in tissue engineering applications for replacement and regeneration of damaged tissue following CNS injury or disease. Subsequent research efforts focused on a novel micropatterning technique called microscale plasma-initiated patterning (microPIP). This patterning method uses a polydimethylsiloxane (PDMS) stamp to selectively protect regions of an underlying substrate from oxygen plasma treatment resulting in hydrophobic and hydrophilic regions. FGF-2 and laminin-1 were applied to an electrospun polyamide nanofibrillar matrix following plasma treatment. In this work it, was possible to demonstrate that textured surfaces, such as nanofibrillar scaffolds, can be micropatterned to provide external chemical cues for cellular organization. Finally, a microsphere system capable of encapsulating proteins while minimizing the mechanisms of protein degradation and providing a controlled release was investigated. Microspheres were comprised of

  15. Scalable synthesis and energy applications of defect engineeered nano materials

    Science.gov (United States)

    Karakaya, Mehmet

    Nanomaterials and nanotechnologies have attracted a great deal of attention in a few decades due to their novel physical properties such as, high aspect ratio, surface morphology, impurities, etc. which lead to unique chemical, optical and electronic properties. The awareness of importance of nanomaterials has motivated researchers to develop nanomaterial growth techniques to further control nanostructures properties such as, size, surface morphology, etc. that may alter their fundamental behavior. Carbon nanotubes (CNTs) are one of the most promising materials with their rigidity, strength, elasticity and electric conductivity for future applications. Despite their excellent properties explored by the abundant research works, there is big challenge to introduce them into the macroscopic world for practical applications. This thesis first gives a brief overview of the CNTs, it will then go on mechanical and oil absorption properties of macro-scale CNT assemblies, then following CNT energy storage applications and finally fundamental studies of defect introduced graphene systems. Chapter Two focuses on helically coiled carbon nanotube (HCNT) foams in compression. Similarly to other foams, HCNT foams exhibit preconditioning effects in response to cyclic loading; however, their fundamental deformation mechanisms are unique. Bulk HCNT foams exhibit super-compressibility and recover more than 90% of large compressive strains (up to 80%). When subjected to striker impacts, HCNT foams mitigate impact stresses more effectively compared to other CNT foams comprised of non-helical CNTs (~50% improvement). The unique mechanical properties we revealed demonstrate that the HCNT foams are ideally suited for applications in packaging, impact protection, and vibration mitigation. The third chapter describes a simple method for the scalable synthesis of three-dimensional, elastic, and recyclable multi-walled carbon nanotube (MWCNT) based light weight bucky-aerogels (BAGs) that are

  16. An albumin-oligonucleotide assembly for potential combinatorial drug delivery and half-life extension applications

    DEFF Research Database (Denmark)

    Kuhlmann, Matthias; Hamming, Jonas Bohn Refslund; Voldum, Anders

    2017-01-01

    The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach, in wh...... technology platform that offers potential combinatorial drug delivery and half-life extension applications.......The long blood circulatory property of human serum albumin, due to engagement with the cellular recycling neonatal Fc receptor (FcRn), is an attractive drug half-life extension enabling technology. This work describes a novel site-specific albumin double-stranded (ds) DNA assembly approach......, in which the 3' or 5' end maleimide-derivatized oligodeoxynucleotides are conjugated to albumin cysteine at position 34 (cys34) and annealed with complementary strands to allow single site-specific protein modification with functionalized ds oligodeoxynucleotides. Electrophoretic gel shift assays...

  17. Preparation and Characterization of P(MAA-g-EG) Nanospheres for Protein Delivery Applications

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Lugo, Madeline [University of Puerto Rico, Mayagueez Campus, Department of Chemical Engineering (United States); Peppas, Nicholas A. [Purdue University, NSF Program on Therapeutic and Diagnostic Devices, School of Chemical Engineering (United States)], E-mail: peppas@ecn.purdue.edu

    2002-04-15

    Novel complexation hydrogel nanospheres of poly(methacrylic acid-grafted-poly(ethylene glycol)) (P(MAA-g-EG)) were prepared by dispersion polymerization to be used for protein delivery applications. Polymerization was conducted in solvents such as deionized water, ethanol/water, sodium hydroxide, hydrochloric acid, and acetic acid solutions. When polymerizing in deionized water we produced nanospheres without agglomeration. Photon correlation spectroscopy studies revealed that the nanospheres possessed a narrow particle size distribution and the size was inversely proportional to the concentration of poly(ethylene glycol) incorporated in the monomer mixture. These nanospheres exhibited pH-sensitivity comparable to that encountered in hydrogel films with the same composition. The composition of the nanospheres was investigated by transmission Fourier transform infrared spectroscopy. The comparison between hydrogel films and nanospheres with the same monomer composition revealed that nanospheres possessed similar spectral characteristics than hydrogel films prepared by the same techniques. These nanospheres could be used for calcitonin release under physiological conditions.

  18. Mesoporous Silica Nanomaterials for Applications in Catalysis, Sensing, Drug Delivery and Gene Transfection

    Energy Technology Data Exchange (ETDEWEB)

    Radu, Daniela Rodica [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    The central theme of this dissertation is represented by the versatility of mesoporous silica nanomaterials in various applications such as catalysis and bio-applications, with main focus on biological applications of Mesoporous Silica Nanospheres (MSN). The metamorphosis that we impose to these materials from catalysis to sensing and to drug and gene delivery is detailed in this dissertation. First, we developed a synthetic method that can fine tune the amount of chemically accessible organic functional groups on the pores surface of MSN by exploiting electrostatic and size matching between the cationic alkylammonium head group of the cetyltrimethylammonium bromide (CTAB) surfactant and various anionic organoalkoxysilane precursors at the micelle-water interface in a base-catalyzed condensation reaction of silicate. Aiming nature imitation, we demonstrated the catalytic abilities of the MSNs, We utilized an ethylenediamine functional group for chelating Cu2+ as a catalytic functional group anchored inside the mesopores. Thus, a polyalkynylene-based conducting polymer (molecular wire) was synthesized within the Cu-functionalized MSNs silica catalyst. For sensing applications, we have synthesized a poly(lactic acid) coated mesoporous silica nanosphere (PLA-MSN) material that serves as a fluorescence sensor system for detection of amino-containing neurotransmitters in neutral aqueous buffer. We exploited the mesoporosity of MSNs for encapsulating pharmaceutical drugs. We examined bio-friendly capping molecules such as polyamidoamine dendrimers of generations G2 to G4, to prevent the drug leaching. Next, the drug delivery system employed MSNs loaded with Doxorubicin, an anticancer drug. The results demonstrated that these nano-Trojan horses have ability to deliver Doxorubicin to cancer cells and induce their death. Finally, to demonstrate the potential of MSN as an universal cellular transmembrane nanovehicle, we anchored positively charged dendrimers on

  19. Facile synthesis of biphasic calcium phosphate microspheres with engineered surface topography for controlled delivery of drugs and proteins.

    Science.gov (United States)

    Zarkesh, Ibrahim; Ghanian, Mohammad Hossein; Azami, Mahmoud; Bagheri, Fatemeh; Baharvand, Hossein; Mohammadi, Javad; Eslaminejad, Mohamadreza Baghaban

    2017-09-01

    Biphasic calcium phosphate (BCP) microspheres are of great interest due to their high stability and osteoinductive properties at specific compositions. However, the need for optimal performance at a unique composition limits their flexibility for tuning drug release by modulation of bulk properties and presents the question of engineering surface topography as an alternative. It is necessary to have a facile method to control surface topography at a defined bulk composition. Here, we have produced BCP microspheres with different surface topographies that have the capability to be used as tunable drug release systems. We synthesized calcium deficient hydroxyapatite (CDHA) microparticles by precipitating calcium and phosphate ions onto ethylenediaminetetraacetic acid (EDTA) templates. The morphology and surface topography of CDHA microparticles were controlled using process parameters, which governed nucleation and growth. These parameters included template concentration, heat rate, and stirring speed. Under low heat rate and static conditions, we could obtain spherical microparticles with long and short nanosheets on their surfaces at low and high EDTA concentrations, respectively. These nanostructured microspheres were subsequently crystallized by thermal treatment to produce EDTA-free BCP microspheres with intact morphology. These biocompatible BCP microspheres were highly effective in loading and prolonged release of both small molecule [dexamethasone (Dex)] and protein [bovine serum albumin (BSA)] models. This strategy has enabled us to control the surface topography of BCP microspheres at defined compositions and holds tremendous promise for drug delivery and tissue engineering applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Hybrid Drug Delivery Patches Based on Spherical Cellulose Nanocrystals and Colloid Titania—Synthesis and Antibacterial Properties

    Directory of Open Access Journals (Sweden)

    Olga L. Evdokimova

    2018-04-01

    Full Text Available Spherical cellulose nanocrystal-based hybrids grafted with titania nanoparticles were successfully produced for topical drug delivery. The conventional analytical filter paper was used as a precursor material for cellulose nanocrystals (CNC production. Cellulose nanocrystals were extracted via a simple and quick two-step process based on first the complexation with Cu(II solution in aqueous ammonia followed by acid hydrolysis with diluted H2SO4. Triclosan was selected as a model drug for complexation with titania and further introduction into the nanocellulose based composite. Obtained materials were characterized by a broad variety of microscopic, spectroscopic, and thermal analysis methods. The drug release studies showed long-term release profiles of triclosan from the titania based nanocomposite that agreed with Higuchi model. The bacterial susceptibility tests demonstrated that released triclosan retained its antibacterial activity against Escherichia coli and Staphylococcus aureus. It was found that a small amount of titania significantly improved the antibacterial activity of obtained nanocomposites, even without immobilization of model drug. Thus, the developed hybrid patches are highly promising candidates for potential application as antibacterial agents.

  1. Application of lean manufacturing concepts to drug discovery: rapid analogue library synthesis.

    Science.gov (United States)

    Weller, Harold N; Nirschl, David S; Petrillo, Edward W; Poss, Michael A; Andres, Charles J; Cavallaro, Cullen L; Echols, Martin M; Grant-Young, Katherine A; Houston, John G; Miller, Arthur V; Swann, R Thomas

    2006-01-01

    The application of parallel synthesis to lead optimization programs in drug discovery has been an ongoing challenge since the first reports of library synthesis. A number of approaches to the application of parallel array synthesis to lead optimization have been attempted over the years, ranging from widespread deployment by (and support of) individual medicinal chemists to centralization as a service by an expert core team. This manuscript describes our experience with the latter approach, which was undertaken as part of a larger initiative to optimize drug discovery. In particular, we highlight how concepts taken from the manufacturing sector can be applied to drug discovery and parallel synthesis to improve the timeliness and thus the impact of arrays on drug discovery.

  2. Synthesis Reasoning and Its Application in Chinese Calligraphy Generation

    Institute of Scientific and Technical Information of China (English)

    XUSong-Hua; PANYun-He; ZHUANGYue-Ting; FRANCISC.M.Lau

    2005-01-01

    In this paper, we address the demanding task of developing intelligent systems equipped with machine creativity that can perform design tasks automatically. The main challenge is how to model human beings' creativity mathematically and mimic such creativity computationally. We propose a “synthesis reasoning model” as the underlying mechanism to simulate human beings’ creative thinking when they are handling design tasks. We present the theory of the synthesis reasoning model, and the detailed procedure of designing an intelligent system based on the model.We offer a case study of an intelligent Chinese calligraphy generation system which we have developed.Based on implementation experiences of the calligraphy generation system as well as a few other systems for solving real-world problems, we suggest a generic methodology for constructing intelligent systems using the synthesis reasoning model.

  3. Nanotechnology applications and approaches for neuroregeneration and drug delivery to the central nervous system.

    Science.gov (United States)

    Silva, Gabriel A

    2010-06-01

    Nanotechnology is the science and engineering concerned with the design, synthesis, and characterization of materials and devices that have a functional organization in at least one dimension on the nanometer (i.e., one billionth of a meter) scale. The potential impact of bottom up self-assembling nanotechnology, custom made molecules that self-assemble or self-organize into higher ordered structures in response to a defined chemical or physical cue, and top down lithographic type technologies where detail is engineered at smaller scales starting from bulk materials, stems from the fact that these nanoengineered materials and devices exhibit emergent mesocale and macroscale chemical and physical properties that are often different than their constituent nanoscale building block molecules or materials. As such, applications of nanotechnology to medicine and biology allow the interaction and integration of cells and tissues with nanoengineered substrates at a molecular (i.e., subcellular) level with a very high degree of functional specificity and control. This review considers applications of nanotechnology aimed at the neuroprotection and functional regeneration of the central nervous system (CNS) following traumatic or degenerative insults, and nanotechnology approaches for delivering drugs and other small molecules across the blood-brain barrier. It also discusses developing platform technologies that may prove to have broad applications to medicine and physiology, including some being developed for rescuing or replacing anatomical and/or functional CNS structures.

  4. Recent advances in engineering microparticles and their nascent utilization in biomedical delivery and diagnostic applications.

    Science.gov (United States)

    Choi, Andrew; Seo, Kyoung Duck; Kim, Do Wan; Kim, Bum Chang; Kim, Dong Sung

    2017-02-14

    Complex microparticles (MPs) bearing unique characteristics such as well-tailored sizes, various morphologies, and multi-compartments have been attempted to be produced by many researchers in the past decades. However, a conventionally used method of fabricating MPs, emulsion polymerization, has a limitation in achieving the aforementioned characteristics and several approaches such as the microfluidics-assisted (droplet-based microfluidics and flow lithography-based microfluidics), electrohydrodynamics (EHD)-based, centrifugation-based, and template-based methods have been recently suggested to overcome this limitation. The outstanding features of complex MPs engineered through these suggested methods have provided new opportunities for MPs to be applied in a wider range of applications including cell carriers, drug delivery agents, active pigments for display, microsensors, interface stabilizers, and catalyst substrates. Overall, the engineered MPs expose their potential particularly in the field of biomedical engineering as the increased complexity in the engineered MPs fulfills well the requirements of the high-end applications. This review outlines the current trends of newly developed techniques used for engineered MPs fabrication and focuses on the current state of engineered MPs in biomedical applications.

  5. Chemically functionalized gold nanoparticles: Synthesis, characterization, and applications

    Science.gov (United States)

    Daniel, Weston Lewis

    This thesis focuses on the development and application of gold nanoparticle based detection systems and biomimetic structures. Each class of modified nanoparticle has properties that are defined by its chemical moieties that interface with solution and the gold nanoparticle core. In Chapter 2, a comparison of the biomolecular composition and binding properties of various preparations of antibody oligonucleotide gold nanoparticle conjugates is presented. These constructs differed significantly in terms of their structure and binding properties. Chapter 3 reports the use of electroless gold deposition as a light scattering signal enhancer in a multiplexed, microarray-based scanometric immunoassay using the gold nanoparticle probes evaluated in Chapter 2. The use of gold development results in greater signal enhancement than the typical silver development, and multiple rounds of metal development were found to increase the resulting signal compared to one development. Chapter 4 describes an amplified scanometric detection method for human telomerase activity. Gold nanoparticles functionalized with specific oligonucleotide sequences can efficiently capture telomerase enzymes and subsequently be elongated. Both the elongated and unmodified oligonucleotide sequences are simultaneously measured. At low telomerase concentrations, elongated strands cannot be detected, but the unmodified sequences, which come from the same probe particles, can be detected because their concentration is higher, providing a novel form of amplification. Chapter 5 reports the development of a novel colorimetric nitrite and nitrate ion assay based upon gold nanoparticle probes functionalized with Griess reaction reagents. This assay takes advantage of the distance-dependent plasmonic properties of the gold nanoparticles and the ability of nitrite ion to facilitate the cross coupling of novel nanoparticle probes. The assay works on the concept of a kinetic end point and can be triggered at the EPA

  6. Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis

    Directory of Open Access Journals (Sweden)

    Anna Kuźnik

    2017-12-01

    Full Text Available The main synthetic routes towards vinylphosphonium salts and their wide applications in organic synthesis are discussed in this review. Particular attention is paid to the use of these compounds as building blocks for the synthesis of carbo- and heterocyclic systems after their prior transformation into the corresponding phosphorus ylides, followed by the intramolecular Wittig reaction with various types of nucleophiles containing a carbonyl function in their structures.

  7. Radiation synthesis and modification of polymers for biomedical applications. Final results of a co-ordinated research project. 1996-2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-12-01

    Radiation techniques are being used for synthesis of hydrogels, functional polymers, interpenetrating systems, chemical modification of surfaces, immobilization of bioactive materials, synthesis of functional micro- and nanospheres and processing of naturally derived biomaterials. Potential medical applications of these biomaterials include implants, topical dressings, treatment devices and drug delivery systems. Biotechnological applications include diagnostic assays, separation and purification systems, immobilized enzyme and cell bioprocesses and cell culture surfaces. The main objective of the CRP on The use of Radiation Processing to Prepare Biomaterials for Application in Medicine was to co-ordinate the research carried out in the participating countries, to ensure that different research programmes complement each other and the information exchange is available to all. Furthermore, the objective was to expand the use of ionizing radiation in two major areas: synthesis of polymers and gels for medical and biotechnological applications, and modification of surfaces to achieve a specific functionality and/or to immobilize bioactive materials. This publication contains 10 reports of participants; each of the reports has been indexed separately.

  8. Radiation synthesis and modification of polymers for biomedical applications. Final results of a co-ordinated research project. 1996-2000

    International Nuclear Information System (INIS)

    2002-12-01

    Radiation techniques are being used for synthesis of hydrogels, functional polymers, interpenetrating systems, chemical modification of surfaces, immobilization of bioactive materials, synthesis of functional micro- and nanospheres and processing of naturally derived biomaterials. Potential medical applications of these biomaterials include implants, topical dressings, treatment devices and drug delivery systems. Biotechnological applications include diagnostic assays, separation and purification systems, immobilized enzyme and cell bioprocesses and cell culture surfaces. The main objective of the CRP on The use of Radiation Processing to Prepare Biomaterials for Application in Medicine was to co-ordinate the research carried out in the participating countries, to ensure that different research programmes complement each other and the information exchange is available to all. Furthermore, the objective was to expand the use of ionizing radiation in two major areas: synthesis of polymers and gels for medical and biotechnological applications, and modification of surfaces to achieve a specific functionality and/or to immobilize bioactive materials. This publication contains 10 reports of participants; each of the reports has been indexed separately

  9. A Review of the Effect of Processing Variables on the Fabrication of Electrospun Nanofibers for Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Viness Pillay

    2013-01-01

    Full Text Available Electrospinning is a fast emerging technique for producing ultrafine fibers by utilizing electrostatic repulsive forces. The technique has gathered much attention due to the emergence of nanotechnology that sparked worldwide research interest in nanomaterials for their preparation and application in biomedicine and drug delivery. Electrospinning is a simple, adaptable, cost-effective, and versatile technique for producing nanofibers. For effective and efficient use of the technique, several processing parameters need to be optimized for fabricating polymeric nanofibers. The nanofiber morphology, size, porosity, surface area, and topography can be refined by varying these parameters. Such flexibility and diversity in nanofiber fabrication by electrospinning has broadened the horizons for widespread application of nanofibers in the areas of drug and gene delivery, wound dressing, and tissue engineering. Drug-loaded electrospun nanofibers have been used in implants, transdermal systems, wound dressings, and as devices for aiding the prevention of postsurgical abdominal adhesions and infection. They show great promise for use in drug delivery provided that one can confidently control the processing variables during fabrication. This paper provides a concise incursion into the application of electrospun nanofibers in drug delivery and cites pertinent processing parameters that may influence the performance of the nanofibers when applied to drug delivery.

  10. A Review of the Effect of Processing Variables on the Fabrication of Electro spun Nano fibers for Drug Delivery Applications

    International Nuclear Information System (INIS)

    Pillay, V.; Dott, C.; Choonara, Y.E.; Tyagi, Ch.; Tomar, L.; Kumar, P.; Toit, L.C.D.; Ndesendo, V.M.K.

    2013-01-01

    Electro spinning is a fast emerging technique for producing ultrafine fibers by utilizing electrostatic repulsive forces. The technique has gathered much attention due to the emergence of nano technology that sparked worldwide research interest in nano materials for their preparation and application in biomedicine and drug delivery. Electro spinning is a simple, adaptable, cost-effective, and versatile technique for producing nano fibers. For effective and efficient use of the technique, several processing parameters need to be optimized for fabricating polymeric nano fibers. The nano fiber morphology, size, porosity, surface area, and topography can be refined by varying these parameters. Such flexibility and diversity in nano fiber fabrication by electro spinning has broadened the horizons for widespread application of nano fibers in the areas of drug and gene delivery, wound dressing, and tissue engineering. Drug-loaded electro spun nano fibers have been used in implants, transdermal systems, wound dressings, and as devices for aiding the prevention of post surgical abdominal adhesions and infection. They show great promise for use in drug delivery provided that one can confidently control the processing variables during fabrication. This paper provides a concise incursion into the application of electro spun nano fibers in drug delivery and cites pertinent processing parameters that may influence the performance of the nano fibers when applied to drug delivery.

  11. Synthesis, properties and applications of biodegradable polymers derived from diols and dicarboxylic acids: from polyesters to poly(ester amide)s.

    Science.gov (United States)

    Díaz, Angélica; Katsarava, Ramaz; Puiggalí, Jordi

    2014-04-25

    Poly(alkylene dicarboxylate)s constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals. Finally, the incorporation of aromatic units and α-amino acids is considered since stiffness of molecular chains and intermolecular interactions can be drastically changed. In fact, poly(ester amide)s derived from naturally occurring amino acids offer great possibilities as biodegradable materials for biomedical applications which are also extensively discussed.

  12. Polymer nanogels: a versatile nanoscopic drug delivery platform

    Science.gov (United States)

    Chacko, Reuben T.; Ventura, Judy; Zhuang, Jiaming; Thayumanavan, S.

    2012-01-01

    In this review we put the spotlight on crosslinked polymer nanogels, a promising platform that has the characteristics of an “ideal” drug delivery vehicle. Some of the key aspects of drug delivery vehicle design like stability, response to biologically relevant stimuli, passive targeting, active targeting, toxicity and ease of synthesis are discussed. We discuss several delivery systems in this light and highlight some examples of systems, which satisfy some or all of these design requirements. In particular, we point to the advantages that crosslinked polymeric systems bring to drug delivery. We review some of the synthetic methods of nanogel synthesis and conclude with the diverse applications in drug delivery where nanogels have been fruitfully employed. PMID:22342438

  13. Formulation development of smart gel periodontal drug delivery system for local delivery of chemotherapeutic agents with application of experimental design.

    Science.gov (United States)

    Dabhi, Mahesh R; Nagori, Stavan A; Gohel, Mukesh C; Parikh, Rajesh K; Sheth, Navin R

    2010-01-01

    Smart gel periodontal drug delivery systems (SGPDDS) containing gellan gum (0.1-0.8% w/v), lutrol F127 (14, 16, and 18% w/v), and ornidazole (1% w/v) were designed for the treatment of periodontal diseases. Each formulation was characterized in terms of in vitro gelling capacity, viscosity, rheology, content uniformity, in vitro drug release, and syringeability. In vitro gelation time and the nature of the gel formed in simulated saliva for prepared formulations showed polymeric concentration dependency. Drug release data from all formulations was fitted to different kinetic models and the Korsemeyer-Peppas model was the best fit model. Drug release was significantly decreased as the concentration of each polymer component was increased. Increasing the concentration of each polymeric component significantly increased viscosity, syringeability, and time for 50%, 70%, and 90% drug release. In conclusion, the formulations described offer a wide range of physical and drug release characteristics. The formulation containing 0.8% w/v of gellan gum and 16% w/v of lutrol F127 exhibited superior physical characteristics.

  14. Marketing: Exploring Applications for Educational Dissemination. Literature Synthesis.

    Science.gov (United States)

    Reed, Linda

    This synthesis of information about marketing and information dissemination of education-related products is divided into three parts: an overview of major writings, specific marketing strategies, and resources for further study. The first part opens with a definition of marketing as it relates to education. A review of the literature provides…

  15. Application of flexible multibody modelling for control synthesis in mechatronics

    NARCIS (Netherlands)

    Aarts, Ronald G.K.M.; van Dijk, Johannes; Brouwer, Dannis Michel; Jonker, Jan B.; Samin, J.C.; Fisette, P.

    2011-01-01

    The models used in the conceptual phase of the mechatronic design should not be too complicated, yet they should capture the dominant system behaviour. This includes the computation of natural frequencies and mode shapes in a relevant frequency range. For the control system synthesis the low

  16. Synthesis and application of branched type II arabinogalactans

    DEFF Research Database (Denmark)

    Andersen, Mathias Christian Franch; Boos, Irene; Ruprecht, Colin

    2017-01-01

    The synthesis of linear- and (1→6)-branched β-(1→3)-D-galactans, structures found in plant arabinogalactan proteins (AGPs) is described. The synthetic strategy relies on iterative couplings of mono- and disaccharide thioglycoside donors, followed by a late stage glycosylation of heptagalactan bac...

  17. Microwave-Assisted Synthesis – Catalytic Applications in Aqueous Media

    Science.gov (United States)

    The development of sustainable methods directed towards the synthesis of molecules is due to the heightened awareness and recognition of alternative eco-friendly and economical protocols that have minimum impact on environment. Among others, microwave (MW)-assisted methodology ha...

  18. Audio system using binaural synthesis for multimodal telepresence applications

    DEFF Research Database (Denmark)

    Madsen, Esben; Markovic, Milos; Olesen, Søren Krarup

    2013-01-01

    are implemented in a distributed manner. Body-tracking of all participants is provided through the system for the purpose of using binaural synthesis for directional sound. Head-worn microphones are used to capture sound, and the visitor is provided with directional sound through headphones. The visitor...

  19. In situ microemulsion synthesis of hydroxyapatite-MgFe{sub 2}O{sub 4} nanocomposite as a magnetic drug delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Foroughi, Firoozeh [Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad (Iran, Islamic Republic of); Hassanzadeh-Tabrizi, S.A., E-mail: tabrizi1980@gmail.com [Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad (Iran, Islamic Republic of); Bigham, Ashkan [Advanced Materials Research Center, Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad (Iran, Islamic Republic of)

    2016-11-01

    In this study, an innovative synthesis process has been developed to produce hydroxyapatite-magnesium ferrite (HA-MgFe{sub 2}O{sub 4}) nanocomposite. In addition, the effect of calcination temperature on drug delivery behavior of produced samples was investigated. HA-MgFe{sub 2}O{sub 4} nanocomposite was prepared via one-step modified reverse microemulsion synthesis route. The resulting products were characterized by X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and Brunauer–Emmett–Teller surface area analysis (BET). The calcined samples at 500 and 700 °C demonstrated mesoporous characteristics and large specific surface areas of 88 and 32 m{sup 2}/g, respectively. TEM and VSM results showed that the nanocomposite calcined at 700 °C has core–shell morphology and a maximum saturation magnetization of 9.47 emu g{sup −1}. - Highlights: • A one-step modified reverse microemulsion method has been used to produce hydroxyapatite-magnesium ferrite. • Nanocomposites were loaded with ibuprofen as a magnetic drug delivery system. • The drug release behavior of nanocomposites were studied at different calcination temperature.

  20. Layer-by-layer assembled multilayers and polymeric nanoparticles for drug delivery in tissue engineering applications

    Science.gov (United States)

    Mehrotra, Sumit

    Tissues and organs in vivo are structured in three dimensional (3-D) ordered assemblies to maintain their metabolic functions. In the case of an injury, certain tissues lack the regenerative abilities without an external supportive environment. In order to regenerate the natural in vivo environment post-injury, there is a need to design three-dimensional (3-D) tissue engineered constructs of appropriate dimensions along with strategies that can deliver growth factors or drugs at a controlled rate from such constructs. This thesis focuses on the applications of hydrogen bonded (H-bonded) nanoscale layer-by-layer (LbL) assembled multilayers for time controlled drug delivery, fabrication of polymeric nanoparticles as drug delivery carriers, and engineering 3-D cellular constructs. Axonal regeneration in the central nervous system after spinal cord injury is often disorganized and random. To support linear axonal growth into spinal cord lesion sites, certain growth factors, such as brain-derived neurotrophic factor (BDNF), needs to be delivered at a controlled rate from an array of uniaxial channels patterned in a scaffold. In this study, we demonstrate for the first time that H-bonded LbL assembled degradable thin films prepared over agarose hydrogel, whereby the protein was loaded separately from the agarose fabrication, provided sustained release of protein under physiological conditions for more than four weeks. Further, patterned agarose scaffolds implanted at the site of a spinal cord injury forms a reactive cell layer of leptomeningeal fibroblasts in and around the scaffold. This limits the ability of axons to reinnervate the spinal cord. To address this challenge, we demonstrate the time controlled release of an anti-mitotic agent from agarose hydrdgel to control the growth of the reactive cell layer of fibroblasts. Challenges in tissue engineering can also be addressed using gene therapy approaches. Certain growth factors in the body are known to inhibit

  1. Recent Advances in Laser-Ablative Synthesis of Bare Au and Si Nanoparticles and Assessment of Their Prospects for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Kattan

    2018-05-01

    Full Text Available Driven by surface cleanness and unique physical, optical and chemical properties, bare (ligand-free laser-synthesized nanoparticles (NPs are now in the focus of interest as promising materials for the development of advanced biomedical platforms related to biosensing, bioimaging and therapeutic drug delivery. We recently achieved significant progress in the synthesis of bare gold (Au and silicon (Si NPs and their testing in biomedical tasks, including cancer imaging and therapy, biofuel cells, etc. We also showed that these nanomaterials can be excellent candidates for tissue engineering applications. This review is aimed at the description of our recent progress in laser synthesis of bare Si and Au NPs and their testing as functional modules (additives in innovative scaffold platforms intended for tissue engineering tasks.

  2. Drug nanocrystals for the formulation of poorly soluble drugs and its application as a potential drug delivery system

    International Nuclear Information System (INIS)

    Gao Lei; Zhang Dianrui; Chen Minghui

    2008-01-01

    Formulation of poorly soluble drugs is a general intractable problem in pharmaceutical field, especially those compounds poorly soluble in both aqueous and organic media. It is difficult to resolve this problem using conventional formulation approaches, so many drugs are abandoned early in discovery. Nanocrystals, a new carrier-free colloidal drug delivery system with a particle size ranging from 100 to 1000 nm, is thought as a viable drug delivery strategy to develop the poorly soluble drugs, because of their simplicity in preparation and general applicability. In this article, the product techniques of the nanocrystals were reviewed and compared, the special features of drug nanocrystals were discussed. The researches on the application of the drug nanocrystals to various administration routes were described in detail. In addition, as introduced later, the nanocrystals could be easily scaled up, which was the prerequisite to the development of a delivery system as a market product

  3. Design and Synthesis of a Novel Class of Flavonoid Derivatives via Sequential Phosphorylation and its Application for Greener Nanoparticle Synthesis

    Science.gov (United States)

    Osonga, Francis Juma

    Flavonoids exhibit arrays of biological effects that are beneficial to humans, including anti-viral, anti-oxidative, anti-inflammatory and anti-carcinogenic effects. However, these applications have been hindered by their poor stability and solubility in common solvents. Consequently, there is significant interest in the modification of flavonoids to improve their solubility. This poor solubility is also believed to be responsible for its permeability and bioavailability. Hence the central goal of this work is to design synthetic strategies for the sequential protection of the -OH groups in order to produce phosphorylated quercetin and apigenin derivatives. This work is divided into two parts: the first part presents the design, synthesis, and characterization of novel flavonoid derivatives via global and sequential phosphorylation. The second part focuses on the application of the synthesized derivatives for greener nanoparticle synthesis. This work shows for the first time that sequential phosphorylation of Quercetin is feasible through the design of 4 new derivatives namely: 5,4'-O-Quercetin Diphosphate (QDPI), 4'-O-phosphate Quercetin (4'-QPI), 5,4'-Quercetin Diphosphate (5,4'-QDP) and monophosphate 4-QP. The synthesis of 4'-QP and 5, 4'-QDP was successful with 85% and 60.5% yields respectively. In addition, the progress towards the total synthesis of apigenin phosphate derivatives (7, 4'-ADP and 7-AP) is presented. The synthesized derivatives were characterized using 1H, 13C, and 31P NMR. The phosphorylated derivatives were subsequently explored as reducing agents for sustainable synthesis of gold, silver and copper nanoparticles. We have successfully demonstrated the photochemical synthesis of gold nanoplates of sizes ranging from 10 - 200 nm using water soluble QDP in the presence of sunlight. This work contributes immensely in promoting the ideals of green nanosynthesis by (i) eliminating the use of organic solvents in the nanosynthesis, (ii) exploiting the

  4. Alkylation of human hair keratin for tunable hydrogel erosion and drug delivery in tissue engineering applications.

    Science.gov (United States)

    Han, Sangheon; Ham, Trevor R; Haque, Salma; Sparks, Jessica L; Saul, Justin M

    2015-09-01

    Polymeric biomaterials that provide a matrix for cell attachment and proliferation while achieving delivery of therapeutic agents are an important component of tissue engineering and regenerative medicine strategies. Keratins are a class of proteins that have received attention for numerous tissue engineering applications because, like other natural polymers, they promote favorable cell interactions and have non-toxic degradation products. Keratins can be extracted from various sources including human hair, and they are characterized by a high percentage of cysteine residues. Thiol groups on reductively extracted keratin (kerateine) form disulfide bonds, providing a more stable cross-linked hydrogel network than oxidatively extracted keratin (keratose) that cannot form disulfide crosslinks. We hypothesized that an iodoacetamide alkylation (or "capping") of cysteine thiol groups on the kerateine form of keratin could be used as a simple method to modulate the levels of disulfide crosslinking in keratin hydrogels, providing tunable rates of gel erosion and therapeutic agent release. After alkylation, the alkylated kerateines still formed hydrogels and the alkylation led to changes in the mechanical and visco-elastic properties of the materials consistent with loss of disulfide crosslinking. The alkylated kerateines did not lead to toxicity in MC3T3-E1 pre-osteoblasts. These cells adhered to keratin at levels comparable to fibronectin and greater than collagen. Alkylated kerateine gels eroded more rapidly than non-alkylated kerateine and this control over erosion led to tunable rates of delivery of rhBMP-2, rhIGF-1, and ciprofloxacin. These results demonstrate that alkylation of kerateine cysteine residues provides a cell-compatible approach to tune rates of hydrogel erosion and therapeutic agent release within the context of a naturally-derived polymeric system. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. A close collaboration of chitosan with lipid colloidal carriers for drug delivery applications.

    Science.gov (United States)

    Bugnicourt, Loïc; Ladavière, Catherine

    2017-06-28

    Chitosan and lipid colloids have separately shown a growing interest in the field of drug delivery applications. Their success is mainly due to their interesting physicochemical behaviors, as well as their biological properties such as bioactivity and biocompatibility. While chitosan is a well-known cationic polysaccharide with the ability to strongly interact with drugs and biological matrices through mainly electrostatic interactions, lipid colloids are carriers particularly recognized for the drug vectorization. In recent years, the combination of both entities has been considered because it offers new systems which gather the advantages of each of them to efficiently deliver various types of bioactive species. The purpose of this review is to describe these associations between chemically-unmodified chitosan chains (solubilized or dispersed) and lipid colloids (as nanoparticles or organized in lipid layers), as well as their potential in the drug delivery area so far. Three assemblies have mainly been reported in the literature: i) lipid nanoparticles (solid lipid nanoparticles or nanostructured lipid carriers) coated with chitosan chains, ii) lipid vesicles covered with chitosan chains, and iii) chitosan chains structured in nanoparticles with a lipid coating. Their elaboration processes, their physicochemical characterization, and their biological studies are detailed and discussed herein. The different bioactive species (drugs and bio(macro)molecules) incorporated in these assemblies, their maximal incorporation efficiency, and their loading capacity are also presented. This review reveals the versatility of these assemblies. Depending on the organization of lipids (i.e., nanoparticles or vesicles) and the state of polymer chains (i.e., solubilized or dispersed under the form of nanoparticles), a large variety of drugs can be successfully incorporated, and various routes of administration can be considered. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Delivery strategies of the CRISPR-Cas9 gene-editing system for therapeutic applications.

    Science.gov (United States)

    Liu, Chang; Zhang, Li; Liu, Hao; Cheng, Kun

    2017-11-28

    The CRISPR-Cas9 genome-editing system is a part of the adaptive immune system in archaea and bacteria to defend against invasive nucleic acids from phages and plasmids. The single guide RNA (sgRNA) of the system recognizes its target sequence in the genome, and the Cas9 nuclease of the system acts as a pair of scissors to cleave the double strands of DNA. Since its discovery, CRISPR-Cas9 has become the most robust platform for genome engineering in eukaryotic cells. Recently, the CRISPR-Cas9 system has triggered enormous interest in therapeutic applications. CRISPR-Cas9 can be applied to correct disease-causing gene mutations or engineer T cells for cancer immunotherapy. The first clinical trial using the CRISPR-Cas9 technology was conducted in 2016. Despite the great promise of the CRISPR-Cas9 technology, several challenges remain to be tackled before its successful applications for human patients. The greatest challenge is the safe and efficient delivery of the CRISPR-Cas9 genome-editing system to target cells in human body. In this review, we will introduce the molecular mechanism and different strategies to edit genes using the CRISPR-Cas9 system. We will then highlight the current systems that have been developed to deliver CRISPR-Cas9 in vitro and in vivo for various therapeutic purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Applications and limitations of lipid nanoparticles in dermal and transdermal drug delivery via the follicular route.

    Science.gov (United States)

    Lauterbach, Andreas; Müller-Goymann, Christel C

    2015-11-01

    Lipid nanoparticles (LN) such as solid lipid nanoparticles (SLN) and nanolipid carriers (NLC) feature several claimed benefits for topical drug therapy including biocompatible ingredients, drug release modification, adhesion to the skin, and film formation with subsequent hydration of the superficial skin layers. However, penetration and permeation into and across deeper skin layers are restricted due to the barrier function of the stratum corneum (SC). As different kinds of nanoparticles provide the potential for penetration into hair follicles (HF) LN are applicable drug delivery systems (DDS) for this route in order to enhance the dermal and transdermal bioavailability of active pharmaceutical ingredients (API). Therefore, this review addresses the HF as application site, published formulations of LN which showed follicular penetration (FP), and characterization methods in order to identify and quantify the accumulation of API delivered by the LN in the HF. Since LN are based on lipids that appear in human sebum which is the predominant medium in HF an increased localization of the colloidal carriers as well as a promoted drug release may be assumed. Therefore, sebum-like lipid material and a size of less or equal 640 nm are appropriate specifications for FP of particulate formulations. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. A convenient method to prepare emulsified polyacrylate nanoparticles from powders [corrected] for drug delivery applications.

    Science.gov (United States)

    Garay-Jimenez, Julio C; Turos, Edward

    2011-08-01

    We describe a method to obtain purified, polyacrylate nanoparticles in a homogeneous powdered form that can be readily reconstituted in aqueous media for in vivo applications. Polyacrylate-based nanoparticles can be easily prepared by emulsion polymerization using a 7:3 mixture of butyl acrylate and styrene in water containing sodium dodecyl sulfate as a surfactant and potassium persulfate as a water-soluble radical initiator. The resulting emulsions contain nanoparticles measuring 40-50 nm in diameter with uniform morphology, and can be purified by centrifugation and dialysis to remove larger coagulants as well as residual surfactant and monomers associated with toxicity. These purified emulsions can be lyophilized in the presence of maltose (a non-toxic cryoprotectant) to provide a homogeneous dried powder, which can be reconstituted as an emulsion by addition of an aqueous diluent. Dynamic light scattering and microbiological experiments were carried out on the reconstituted nanoparticles. This procedure allows for ready preparation of nanoparticle emulsions for drug delivery applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Self-emulsifying drug delivery systems (SEDDS): formulation development, characterization, and applications.

    Science.gov (United States)

    Singh, Bhupinder; Bandopadhyay, Shantanu; Kapil, Rishi; Singh, Ramandeep; Katare, O

    2009-01-01

    Self-emulsifying drug delivery systems (SEDDS) possess unparalleled potential in improving oral bioavailability of poorly water-soluble drugs. Following their oral administration, these systems rapidly disperse in gastrointestinal fluids, yielding micro- or nanoemulsions containing the solubilized drug. Owing to its miniscule globule size, the micro/nanoemulsifed drug can easily be absorbed through lymphatic pathways, bypassing the hepatic first-pass effect. We present an exhaustive and updated account of numerous literature reports and patents on diverse types of self-emulsifying drug formulations, with emphasis on their formulation, characterization, and systematic optimization strategies. Recent advancements in various methodologies employed to characterize their globule size and shape, ability to encapsulate the drug, gastrointestinal and thermodynamic stability, rheological characteristics, and so forth, are discussed comprehensively to guide the formula-tor in preparing an effective and robust SEDDS formulation. Also, this exhaustive review offers an explicit discussion on vital applications of the SEDDS in bioavailability enhancement of various drugs, outlining an overview on myriad in vitro, in situ, and ex vivo techniques to assess the absorption and/ or permeation potential of drugs incorporated in the SEDDS in animal and cell line models, and the subsequent absorption pathways followed by them. In short, the current article furnishes an updated compilation of wide-ranging information on all the requisite vistas of the self-emulsifying formulations, thus paving the way for accelerated progress into the SEDDS application in pharmaceutical research.

  10. Phytosome and Liposome: The Beneficial Encapsulation Systems in Drug Delivery and Food Application

    Directory of Open Access Journals (Sweden)

    Nayyer Karimi

    2015-06-01

    Full Text Available Due to poor solubility in lipids, many of bioactive components (Nutraceutical materials show less bioactivity than optimal state in water solution. Phytosomes improve absorption and bioavailability of biomaterials. Liposomes, spherical shaped nanocarriers, were discovered in the 1960s by bangham. Due to their composition, variability and structural properties, liposomes and phytosomes are extremely versatile, leading to a large number of applications including pharmaceutical, cosmetics and food industrial fields. They are advanced forms of herbal formulations containing the bioactive phytoconstituents of herb extracts such as flavonoids, glycosides and terpenoids, which have good ability to transit from a hydrophilic environment into the lipid friendly environment of the outer cell membrane. They have better bioavailability and actions than the conventional herbal extracts containing dosage. Phytosome technology has increasing effect on the bioavailability of herbal extracts including ginkgo biloba, grape seed, green tea, milk thistle, ginseng, etc., and can be developed for various therapeutic uses or dietary supplements. Liposomes are composed of bilayer membranes, which are made of lipid molecules. They form when phospholipids are dispersed in aqueous media and exposed to high shear rates by using micro-fluidization or colloid mill. The mechanism for formation of liposomes is mainly the hydrophilic–hydrophobic interactions between phospholipids and water molecules. Here, we attempt to review the features of phytosomes and liposomes as well as their preparation methods and capacity in food and drug applications. Generally, it is believed that phytosomes and liposomes are suitable delivery systems for nutraceuticals, and can be widely used in food industry.

  11. High intensity focused ultrasound technology, its scope and applications in therapy and drug delivery.

    Science.gov (United States)

    Phenix, Christopher Peter; Togtema, Melissa; Pichardo, Samuel; Zehbe, Ingeborg; Curiel, Laura

    2014-01-01

    Ultrasonography is a safe, inexpensive and wide-spread diagnostic tool capable of producing real-time non-invasive images without significant biological effects. However, the propagation of higher energy, intensity and frequency ultrasound waves through living tissues can induce thermal, mechanical and chemical effects useful for a variety of therapeutic applications. With the recent development of clinically approved High Intensity Focused Ultrasound (HIFU) systems, therapeutic ultrasound is now a medical reality. Indeed, HIFU has been used for the thermal ablation of pathological lesions; localized, minimally invasive ultrasound-mediated drug delivery through the transient formation of pores on cell membranes; the temporary disruption of skin and the blood brain barrier; the ultrasound induced break-down of blood clots; and the targeted release of drugs using ultrasound and temperature sensitive drug carriers. This review seeks to engage the pharmaceutical research community by providing an overview on the biological effects of ultrasound as well as highlighting important therapeutic applications, current deficiencies and future directions.

  12. Proposal of a service delivery integration index of home care for older persons: application in several European cities

    Directory of Open Access Journals (Sweden)

    Jean-Claude Henrard

    2006-07-01

    Full Text Available Purpose: To propose an integration index of home care delivery to older persons, to study its validity and to apply it to home care services of European cities. Theory: Home care delivery integration was based on two dimensions referring to process-centred integration and organisational structure approach. Method: Items considered as part of both dimensions according to an expert consensus (face validity were extracted from a standardised questionnaire used in “Aged in Home care” (AdHoc study to capture basic characteristics of home care services. Their summation leads to a services' delivery integration index. This index was applied to AdHoc services. A factor analysis was computed in order to empirically test the validity of the theoretical constructs. The plot of the settings was performed. Results: Application of the index ranks home care services in four groups according to their score. Factor analysis identifies a first factor which opposes working arrangement within service to organisational structure bringing together provisions for social care. A second factor corresponds to basic nursing care and therapies. Internal consistency for those three domains ranges from 0.78 to 0.93. When plotting the different settings different models of service delivery appear. Conclusion: The proposed index shows that behind a total score several models of care delivery are hidden. Comparison of service delivery integration should take into account this heterogeneity.

  13. Synthesis, characterization, and in vitro evaluation of novel polymer-coated magnetic nanoparticles for controlled delivery of doxorubicin

    Directory of Open Access Journals (Sweden)

    Akbarzadeh A

    2012-02-01

    Full Text Available Abolfazl Akbarzadeh1, Nosratollah Zarghami2, Haleh Mikaeili3, Davoud Asgari4, Amir Mohammad Goganian5, Hanie Khaksar Khiabani5, Mohammad Samiei6, Soodabeh Davaran31Department of Medicinal Chemistry, Tabriz University of Medical Sciences, 2Department of Clinical Biochemistry and Laboratory Medicine, Division of Medical Biotechnology, Faculty of Medicine, Tabriz University of Medical Sciences, 3Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, 4Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, 5Department of Organic Chemistry, Faculty of Chemistry, University of Tabriz, 6Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, IranAbstract: Poly (N-isopropylacrylamide-methyl methacrylic acid, PNIPAAm-MAA-grafted magnetic nanoparticles were synthesized using silane-coated magnetic nanoparticles as a template for radical polymerization of N-isopropylacrylamide and methacrylic acid. Properties of these nanoparticles, such as size, drug-loading efficiency, and drug release kinetics, were evaluated in vitro for targeted and controlled drug delivery. The resulting nanoparticles had a diameter of 100 nm and a doxorubicin-loading efficiency of 75%, significantly higher doxorubicin release at 40°C compared with 37°C, and pH 5.8 compared with pH 7.4, demonstrating their temperature and pH sensitivity, respectively. In addition, the particles were characterized by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. In vitro cytotoxicity testing showed that the PNIPAAm-MAA-coated magnetic nanoparticles had no cytotoxicity and were biocompatible, indicating their potential for biomedical application.Keywords: magnetic nanoparticles, drug loading, doxorubicin release, biocompatibility

  14. Short-peptide-based molecular hydrogels: novel gelation strategies and applications for tissue engineering and drug delivery

    Science.gov (United States)

    Wang, Huaimin; Yang, Zhimou

    2012-08-01

    Molecular hydrogels hold big potential for tissue engineering and controlled drug delivery. Our lab focuses on short-peptide-based molecular hydrogels formed by biocompatible methods and their applications in tissue engineering (especially, 3D cell culture) and controlled drug delivery. This feature article firstly describes our recent progresses of the development of novel methods to form hydrogels, including the strategy of disulfide bond reduction and assistance with specific protein-peptide interactions. We then introduce the applications of our hydrogels in fields of controlled stem cell differentiation, cell culture, surface modifications of polyester materials by molecular self-assembly, and anti-degradation of recombinant complex proteins. A novel molecular hydrogel system of hydrophobic compounds that are only formed by hydrolysis processes was also included in this article. The hydrogels of hydrophobic compounds, especially those of hydrophobic therapeutic agents, may be developed into a carrier-free delivery system for long term delivery of therapeutic agents. With the efforts in this field, we believe that molecular hydrogels formed by short peptides and hydrophobic therapeutic agents can be practically applied for 3D cell culture and long term drug delivery in near future, respectively.

  15. Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Han,W.Q.

    2008-08-01

    Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient pressure. c-BN is synthesized from h-BN under high pressure at high temperature while w-BN is prepared from h-BN under high pressure at room temperature [1]. Each BN layer consists of stacks of hexagonal plate-like units of boron and nitrogen atoms linked by SP{sup 2} hybridized orbits and held together mainly by Van der Waals force (Fig 1(b)). The hexagonal polymorph has two-layered repeating units: AA'AA'... that differ from those in graphite: ABAB... (Figure 1(a)). Within the layers of h-BN there is coincidence between the same phases of the hexagons, although the boron atoms and nitrogen atoms are alternatively located along the c

  16. Polymer and polymer-hybrid nanoparticles from synthesis to biomedical applications

    CERN Document Server

    Rangelov, Stanislav

    2013-01-01

    Polymeric and hybrid nanoparticles have received increased scientific interest in terms of basic research as well as commercial applications, promising a variety of uses for nanostructures in fields including bionanotechnology and medicine. Condensing the relevant research into a comprehensive reference, Polymer and Polymer-Hybrid Nanoparticles: From Synthesis to Biomedical Applications covers an array of topics from synthetic procedures and macromolecular design to possible biomedical applications of nanoparticles and materials based on original and unique polymers. The book presents a well-r

  17. Multifunctional quantum dots and liposome complexes in drug delivery

    Science.gov (United States)

    Wang, Qi; Chao, Yimin

    2018-01-01

    Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches. PMID:28866655

  18. Multifunctional quantum dots and liposome complexes in drug delivery.

    Science.gov (United States)

    Wang, Qi; Chao, Yi-Min

    2017-09-03

    Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots (QDs) has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system (L-QD). Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches.

  19. The application of green chemistry methods in organophosphorus synthesis

    International Nuclear Information System (INIS)

    Odinets, Irina L; Matveeva, E V

    2012-01-01

    Data concerning the synthesis of organophosphorus compounds in ionic liquids, in water and under solvent-free conditions are considered and summarized. It is shown that this strategy, which complies with the definition of green chemistry, has advantages in terms of the rate of the process and the yields of target products as compared with syntheses in common organic solvents. The Wittig, Horner–Wadsworth–Emmons, Kabachnik–Fields, Arbuzov and Michaelis reactions are considered as examples. The bibliography includes 178 references.

  20. Bioinspired thymine functionalized polymeric systems: from synthesis to nano applications

    OpenAIRE

    Kaur, Gagan Deep

    2017-01-01

    Nature is an abundant source of elegant examples of synthesis of materials, and as in many other areas of science, polymer chemists have been drawing on bioinspiration to create sophisticated functional materials. Thymine, one of the nucleic bases in DNA, is well known for its ability to form relatively strong hydrogen bonds as well as its propensity to undergo reversible photo-dimerization upon UV exposure. The focus of this thesis is to develop a bioinspired thymine functionalized polymeric...

  1. Molecularly Imprinted Polymer Beads-Synthesis, Evaluation and Applications

    OpenAIRE

    Zhou, Tongchang

    2016-01-01

    Molecularly imprinted polymers (MIPs) are artificial receptors designed for the selective recognition of template molecules. These polymers have been applied in analytical separations, as chemical sensors and in drug delivery system due to their low cost and high stability. In recent years MIP beads, especially those with good selectivity in aqueous solution, have become attractive as they can be potentially used as selective adsorbents for the solid phase extraction (SPE) and chromatographic...

  2. Synthesis, Characterization and Applications in Catalysis of Polyoxometalate/Zeolite Composites

    Directory of Open Access Journals (Sweden)

    Frédéric Lefebvre

    2016-05-01

    Full Text Available An overview of the synthesis, characterization and catalytic applications of polyoxometalates/zeolites composites is given. The solids obtained by direct synthesis of the polyoxometalate in the presence of the zeolite are first described with their applications in catalysis. Those obtained by a direct mixing of the two components are then reviewed. In all cases, special care is taken in the localization of the polyoxometalate, inside the zeolite crystal, in mesopores or at the external surface of the crystals, as deduced from the characterization methods.

  3. Poly(o-aminophenol) film electrodes synthesis, transport properties and practical applications

    CERN Document Server

    Tucceri, Ricardo

    2014-01-01

    This review book is concerned with the synthesis, charge transport properties and practical applications of poly (o-aminophenol) (POAP) film electrodes. It is divided into three parts. The first one has a particular emphasis on problems of synthesis and structure of POAP. The second part deals with the mechanism of charge transfer and charge transport processes occurring in the course of the redox reactions of POAP. The third part describes the promising applications of POAP in the different fields of sensors, electrocatalysis, bioelectrochemistry, corrosion protection, among others. This review covers the literature on POAP in the time period comprised between 1987 and 2013.

  4. A microwave-assisted solution combustion synthesis to produce europium-doped calcium phosphate nanowhiskers for bioimaging applications.

    Science.gov (United States)

    Wagner, Darcy E; Eisenmann, Kathryn M; Nestor-Kalinoski, Andrea L; Bhaduri, Sarit B

    2013-09-01

    Biocompatible nanoparticles possessing fluorescent properties offer attractive possibilities for multifunctional bioimaging and/or drug and gene delivery applications. Many of the limitations with current imaging systems center on the properties of the optical probes in relation to equipment technical capabilities. Here we introduce a novel high aspect ratio and highly crystalline europium-doped calcium phosphate nanowhisker produced using a simple microwave-assisted solution combustion synthesis method for use as a multifunctional bioimaging probe. X-ray diffraction confirmed the material phase as europium-doped hydroxyapatite. Fluorescence emission and excitation spectra and their corresponding peaks were identified using spectrofluorimetry and validated with fluorescence, confocal and multiphoton microscopy. The nanowhiskers were found to exhibit red and far red wavelength fluorescence under ultraviolet excitation with an optimal peak emission of 696 nm achieved with a 350 nm excitation. Relatively narrow emission bands were observed, which may permit their use in multicolor imaging applications. Confocal and multiphoton microscopy confirmed that the nanoparticles provide sufficient intensity to be utilized in imaging applications. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. From Tactical to Strategic Deception Detection: Application of Psychological Synthesis

    Directory of Open Access Journals (Sweden)

    Iain Reid

    2017-03-01

    Full Text Available Deception detection has ubiquitously focussed upon detecting deceit in the individual, whether in national security, forensic or business-related environments. In contrast an understanding of how to identify deception committed by multiple individuals or groups challenging strategic interests has been neglected. In this article - to enhance understanding of practitioners working across security, intelligence and forensic areas - a process of psychological synthesis is advocated. Psychological synthesis incorporates a multitude of approaches reflecting contextual requirements towards deception detection across verbal/linguistic behavior, non-verbal behavior, online interactions and intelligence analysis approaches. These combined with in-depth understanding of individuals’ cultures, personality and manner of presentation can be understood in challenging environments. Juxtaposed to these factors psychological synthesis considers how intelligence, surveillance and evidence may be used in detecting deception and identifying links between individuals engaging in deception and related activities. An illustration of how such an approach may work is provided through a scenario of a terrorist incident and how a tailored deception detection approach may seek to counter such a threat.

  6. Size Controlled Synthesis of Transition Metal Nanoparticles for Catalytic Applications

    KAUST Repository

    Esparza, Angel

    2011-07-07

    Catalysis offers cleaner and more efficient chemical reactions for environmental scientists. More than 90% of industrial processes are performed with a catalyst involved, however research it is still required to improve the catalyst materials. The purpose of this work is to contribute with the development of catalysts synthesis with two different approaches. First, the precise size control of non-noble metals nanoparticles. Second, a new one-pot synthesis method based on a microemulsion system was developed to synthesize size-controlled metal nanoparticles in oxide supports. The one-pot method represents a simple approach to synthesize both support and immobilized nanometer-sized non-noble metal nanoparticles in the same reaction system. Narrow size distribution nickel, cobalt, iron and cobalt-nickel nanoparticles were obtained. High metal dispersions are attainable regardless the metal or support used in the synthesis. Thus, the methodology is adaptable and robust. The sizecontrolled supported metal nanoparticles offer the opportunity to study size effects and metal-support interactions on different catalytic reactions with different sets of metals and supports.

  7. Adamantane in Drug Delivery Systems and Surface Recognition

    OpenAIRE

    Adela Štimac; Marina Šekutor; Kata Mlinarić-Majerski; Leo Frkanec; Ruža Frkanec

    2017-01-01

    The adamantane moiety is widely applied in design and synthesis of new drug delivery systems and in surface recognition studies. This review focuses on liposomes, cyclodextrins, and dendrimers based on or incorporating adamantane derivatives. Our recent concept of adamantane as an anchor in the lipid bilayer of liposomes has promising applications in the field of targeted drug delivery and surface recognition. The results reported here encourage the development of novel adamantane-based struc...

  8. Application of in situ polymerization for design and development of oral drug delivery systems.

    Science.gov (United States)

    Ngwuluka, Ndidi

    2010-12-01

    Although preformed polymers are commercially available for use in the design and development of drug delivery systems, in situ polymerization has also been employed. In situ polymerization affords the platform to tailor and optimize the drug delivery properties of polymers. This review brings to light the benefits of in situ polymerization for oral drug delivery and the possibilities it provides to overcome the challenges of oral route of administration.

  9. Application of In Situ Polymerization for Design and Development of Oral Drug Delivery Systems

    OpenAIRE

    Ngwuluka, Ndidi

    2010-01-01

    Although preformed polymers are commercially available for use in the design and development of drug delivery systems, in situ polymerization has also been employed. In situ polymerization affords the platform to tailor and optimize the drug delivery properties of polymers. This review brings to light the benefits of in situ polymerization for oral drug delivery and the possibilities it provides to overcome the challenges of oral route of administration.

  10. Synthesis, characterization, and application of surface-functionalized ordered mesoporous nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Po-Wen [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    The dissertation begins with Chapter 1, which is a general introduction of the fundamental synthesis of mesoporous silica materials, the selective functionlization of mesoporous silica materials, and the synthesis of nanostructured porous materials via nanocasting. In Chapter 2, the thermo-responsive polymer coated mesoporous silica nanoparticles (MSN) was synthesized via surface-initated polymerization and exhibited unique partition activities in a biphasic solution with the thermally induced change. In Chapter 3, the monodispersed spherical MSN with different mesoporous structure (MCM-48) was developed and employed as a template for the synthesis of mesoporous carbon nanoparticles (MCN) via nanocasting. MCN was demonstrated for the delivery of membrane impermeable chemical agents inside the cells. The cellular uptake efficiency and biocompabtibility of MCN with human cervical cancer cells were also investigated. In addition to the biocompabtibility of MCN, MCN was demonstrated to support Rh-Mn nanoparticles for catalytic reaction in Chapter 4. Owing to the unique mesoporosity, Rh-Mn nanoparticles can be well distributed inside the mesoporous structure and exhibited interesting catalytic performance on CO hydrogenation. In Chapter 5, the synthesis route of the aforementioned MCM-48 MSN was discussed and investigated in details and other metal oxide nanoparticles were also developed via nanocasting by using MCM-48 MSN as a template. At last, there is a general conclusion summarized in Chapter 6.

  11. Transdermal and intradermal delivery of therapeutic agents: application of physical technologies

    National Research Council Canada - National Science Library

    Banga, Ajay K

    2011-01-01

    .... Commercialization of transdermal drug delivery requires technology from many disciplines beyond pharmaceutical sciences, such as polymer chemistry, adhesion sciences, mass transport, web film coating...

  12. Composite magnetic nanoparticles: Synthesis and cancer-related applications

    International Nuclear Information System (INIS)

    Cai Ping; Chen Hong-Min; Xie Jin

    2014-01-01

    Recent advances in the preparation and applications of composite magnetic nanoparticles are reviewed and summarized, with a focus on cancer-related applications. (topical review - magnetism, magnetic materials, and interdisciplinary research)

  13. Relevance of nanotechnology to Africa: synthesis, applications and safety

    CSIR Research Space (South Africa)

    Musee, N

    2012-07-01

    Full Text Available In this chapter, two nanotechnology-based applications relevant to Africa in promoting sustainability and achievement of the Millennium Development Goals (MDGs) are presented. The applications comprise the provision of therapeutic treatment...

  14. Controlled Synthesis of Monolayer Graphene Toward Transparent Flexible Conductive Film Application

    Directory of Open Access Journals (Sweden)

    Yu Han-Young

    2010-01-01

    Full Text Available Abstract We demonstrate the synthesis of monolayer graphene using thermal chemical vapor deposition and successive transfer onto arbitrary substrates toward transparent flexible conductive film application. We used electron-beam-deposited Ni thin film as a synthetic catalyst and introduced a gas mixture consisting of methane and hydrogen. To optimize the synthesis condition, we investigated the effects of synthetic temperature and cooling rate in the ranges of 850–1,000°C and 2–8°C/min, respectively. It was found that a cooling rate of 4°C/min after 1,000°C synthesis is the most effective condition for monolayer graphene production. We also successfully transferred as-synthesized graphene films to arbitrary substrates such as silicon-dioxide-coated wafers, glass, and polyethylene terephthalate sheets to develop transparent, flexible, and conductive film application.

  15. Improvement of interaction between PVA and chitosan via magnetite nanoparticles for drug delivery application.

    Science.gov (United States)

    Shagholani, Hamidreza; Ghoreishi, Sayed Mehdi; Mousazadeh, Mohammad

    2015-01-01

    Magnetite nanoparticles were synthesized by coprecipitation under ultrasonication followed by coating with chitosan. Polyvinyl alcohol (PVA) is then combined with the chitosan that coated the magnetite nanoparticles. The combination occurs by hydrogen binding and ionic cross-linking of the amino and hydroxyl groups of chitosan and PVA respectively. The magnetite nanoparticles have an average size of 10.62 nm that was confirmed by TEM. The VSM measurements showed that nanoparticles were superparamagnetic. The coatings on the core nanoparticles were estimated by AAS and the attachments of coating to the nanoparticles were confirmed by FT-IR analysis. Physicochemical properties of nanoparticles were measured by DLS and zeta potential. Naked magnetite, chitosan and PVA coating have zeta potential of +36.4, +48.1 and -12.5 mV respectively. The unspecific adsorption and interaction between nanoparticles and bovine serum albumin (BSA) were investigated systematically by UV-vis spectroscopy method. The nanoparticles that were modified by PVA present low protein adsorption, which makes them a practical choice for preventing opsonization in clinical application and drug delivery. Copyright © 2015. Published by Elsevier B.V.

  16. Stimuli-Responsive Block Copolymer-Based Assemblies for Cargo Delivery and Theranostic Applications

    Directory of Open Access Journals (Sweden)

    Jun Yin

    2016-07-01

    Full Text Available Although a number of tactics towards the fabrication and biomedical exploration of stimuli-responsive polymeric assemblies being responsive and adaptive to various factors have appeared, the controlled preparation of assemblies with well-defined physicochemical properties and tailor-made functions are still challenges. These responsive polymeric assemblies, which are triggered by stimuli, always exhibited reversible or irreversible changes in chemical structures and physical properties. However, simple drug/polymer nanocomplexes cannot deliver or release drugs into the diseased sites and cells on-demand due to the inevitable biological barriers. Hence, utilizing therapeutic or imaging agents-loaded stimuli-responsive block copolymer assemblies that are responsive to tumor internal microenvironments (pH, redox, enzyme, and temperature, etc. or external stimuli (light and electromagnetic field, etc. have emerged to be an important solution to improve therapeutic efficacy and imaging sensitivity through rationally designing as well as self-assembling approaches. In this review, we summarize a portion of recent progress in tumor and intracellular microenvironment responsive block copolymer assemblies and their applications in anticancer drug delivery and triggered release and enhanced imaging sensitivity. The outlook on future developments is also discussed. We hope that this review can stimulate more revolutionary ideas and novel concepts and meet the significant interest to diverse readers.

  17. Frequency-controlled wireless shape memory polymer microactuator for drug delivery application.

    Science.gov (United States)

    Zainal, M A; Ahmad, A; Mohamed Ali, M S

    2017-03-01

    This paper reports the wireless Shape-Memory-Polymer actuator operated by external radio frequency magnetic fields and its application in a drug delivery device. The actuator is driven by a frequency-sensitive wireless resonant heater which is bonded directly to the Shape-Memory-Polymer and is activated only when the field frequency is tuned to the resonant frequency of heater. The heater is fabricated using a double-sided Cu-clad Polyimide with much simpler fabrication steps compared to previously reported methods. The actuation range of 140 μm as the tip opening distance is achieved at device temperature 44 °C in 30 s using 0.05 W RF power. A repeatability test shows that the actuator's average maximum displacement is 110 μm and standard deviation of 12 μm. An experiment is conducted to demonstrate drug release with 5 μL of an acidic solution loaded in the reservoir and the device is immersed in DI water. The actuator is successfully operated in water through wireless activation. The acidic solution is released and diffused in water with an average release rate of 0.172 μL/min.

  18. Temperature-Responsive Smart Nanocarriers for Delivery Of Therapeutic Agents: Applications and Recent Advances.

    Science.gov (United States)

    Karimi, Mahdi; Sahandi Zangabad, Parham; Ghasemi, Alireza; Amiri, Mohammad; Bahrami, Mohsen; Malekzad, Hedieh; Ghahramanzadeh Asl, Hadi; Mahdieh, Zahra; Bozorgomid, Mahnaz; Ghasemi, Amir; Rahmani Taji Boyuk, Mohammad Reza; Hamblin, Michael R

    2016-08-24

    Smart drug delivery systems (DDSs) have attracted the attention of many scientists, as carriers that can be stimulated by changes in environmental parameters such as temperature, pH, light, electromagnetic fields, mechanical forces, etc. These smart nanocarriers can release their cargo on demand when their target is reached and the stimulus is applied. Using the techniques of nanotechnology, these nanocarriers can be tailored to be target-specific, and exhibit delayed or controlled release of drugs. Temperature-responsive nanocarriers are one of most important groups of smart nanoparticles (NPs) that have been investigated during the past decades. Temperature can either act as an external stimulus when heat is applied from the outside, or can be internal when pathological lesions have a naturally elevated termperature. A low critical solution temperature (LCST) is a special feature of some polymeric materials, and most of the temperature-responsive nanocarriers have been designed based on this feature. In this review, we attempt to summarize recent efforts to prepare innovative temperature-responsive nanocarriers and discuss their novel applications.

  19. Ferritin cage for encapsulation and delivery of bioactive nutrients: From structure, property to applications.

    Science.gov (United States)

    Zang, Jiachen; Chen, Hai; Zhao, Guanghua; Wang, Fudi; Ren, Fazheng

    2017-11-22

    Ferritin is a class of naturally occurring iron storage proteins, which is distributed widely in animal, plant, and bacteria. It usually consists of 24 subunits that form a hollow protein shell with high symmetry. One holoferritin molecule can store up to 4500 iron atom within its inner cavity, and it becomes apoferritin upon removal of iron from the cavity. Recently, scientists have subverted these nature functions and used reversibly self-assembled property of apoferritin cage controlled by pH for the encapsulation and delivery of bioactive nutrients or anticancer drug. In all these cases, the ferritin cages shield their cargo from the influence of external conditions and provide a controlled microenvironment. More importantly, upon encapsulation, ferritin shell greatly improved the water solubility, thermal stability, photostability, and cellular uptake activity of these small bioactive compounds. This review aims to highlight recent advances in applications of ferritin cage as a novel vehicle in the field of food science and nutrition. Future outlooks are highlighted with the aim to suggest a research line to follow for further studies.

  20. Design and application of cationic amphiphilic β-cyclodextrin derivatives as gene delivery vectors

    Science.gov (United States)

    Wan, Ning; Huan, Meng-Lei; Ma, Xi-Xi; Jing, Zi-Wei; Zhang, Ya-Xuan; Li, Chen; Zhou, Si-Yuan; Zhang, Bang-Le

    2017-11-01

    The nano self-assembly profiles of amphiphilic gene delivery vectors could improve the density of local cationic head groups to promote their DNA condensation capability and enhance the interaction between cell membrane and hydrophobic tails, thus increasing cellular uptake and gene transfection. In this paper, two series of cationic amphiphilic β-cyclodextrin (β-CD) derivatives were designed and synthesized by using 6-mono-OTs-β-CD (1) as the precursor to construct amphiphilic gene vectors with different building blocks in a selective and controlled manner. The effect of different type and degree of cationic head groups on transfection and the endocytic mechanism of β-CD derivatives/DNA nanocomplexes were also investigated. The results demonstrated that the designed β-cyclodextrin derivatives were able to compact DNA to form stable nanocomplexes and exhibited low cytotoxicity. Among them, PEI-1 with PEI head group showed enhanced transfection activity, significantly higher than commercially available agent PEI25000 especially in the presence of serum, showing potential application prospects in clinical trials. Moreover, the endocytic uptake mechanism involved in the gene transfection of PEI-1 was mainly through caveolae-mediated endocytosis, which could avoid the lysosomal degradation of loaded gene, and had great importance for improving gene transfection activity.

  1. Controlled adsorption and release onto calcium phosphates materials and drug delivery applications

    Directory of Open Access Journals (Sweden)

    Barroug A.

    2013-11-01

    Full Text Available The adsorptive properties of synthetic calcium phosphates analogous to bone mineral were examined with respect to cisplatin and risedronate, two biological active drugs; the uptake and release experiments were carried out under various conditions in order to understand the basic mechanism of interaction. The effect of temperature and solution composition were highlighted and discussed. The adsorption results obtained for the therapeutic agents demonstrated that, depending on the conditions investigated (nature of the sorbent, concentration range, ionic composition, temperature…, the shape of the isotherms is of Freundlich or Langmuir type. The adsorption is described as an ion-exchange process in dilute solutions, while the interaction appears to be reactive for concentrated solutions (dissolution of mineral ions from the apatite substrate and formation of soluble calcium complex and/or precipitation of calcium salts involving sorbate molecules. The information gained on the surface reactivity of calcium phosphate were exploited to associate an antibiotic to calcium phosphate cements for drug delivery applications. The specimens were obtained by combination of calcium phosphate and calcium carbonate powders upon mixing with water. The physicochemical properties of the paste were altered by the drug loading method (in the liquid or solid phase. Thus, a dose-dependent effect was noticed for the paste setting time, hardening and the release process.

  2. Development of a DNA-liposome complex for gene delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Rasoulianboroujeni, M. [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States); Kupgan, G. [Department of Chemical Engineering, Oklahoma State University, 423 Engineering North, Stillwater, OK 74078 (United States); Moghadam, F. [School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ (United States); Tahriri, M. [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States); Boughdachi, A. [Polymer Engineering Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Khoshkenar, P. [Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 (United States); Ambrose, J.J. [Biomedical Engineering Department, Louisiana Tech University, Ruston, LA 71272 (United States); Kiaie, N. [Tissue Engineering Department, Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Vashaee, D. [Electrical and Computer Engineering Department, North Carolina State University, Raleigh, NC 27606 (United States); Ramsey, J.D. [Department of Chemical Engineering, Oklahoma State University, 423 Engineering North, Stillwater, OK 74078 (United States); Tayebi, L., E-mail: lobat.tayebi@marquette.edu [Marquette University School of Dentistry, Milwaukee, WI 53233 (United States)

    2017-06-01

    The association structures formed by cationic liposomes and DNA (Deoxyribonucleic acid)-liposome have been effectively utilized as gene carriers in transfection assays. In this research study, cationic liposomes were prepared using a modified lipid film hydration method consisting of a lyophilization step for gene delivery applications. The obtained results demonstrated that the mean particle size had no significant change while the polydispersity (PDI) increased after lyophilization. The mean particle size slightly reduced after lyophilization (520 ± 12 nm to 464 ± 25 nm) while the PDI increased after lyophilization (0.094 ± 0.017 to 0.220 ± 0.004). In addition. The mean particle size of vesicles increases when DNA is incorporated to the liposomes (673 ± 27 nm). According to the Scanning Electron Microscopy (SEM) and transmission electron microscopy (TEM) images, the spherical shape of liposomes confirmed their successful preservation and reconstitution from the powder. It was found that liposomal formulation has enhanced transfection considerably compared to the naked DNA as negative control. Finally, liposomal formulation in this research had a better function than Lipofectamine® 2000 as a commercialized product because the cellular activity (cellular protein) was higher in the prepared lipoplex than Lipofectamine® 2000. - Highlights: • Liposomal formulation in this research had a better function than Lipofectamine® 2000. • The average particle size had no significant change while the PDI increased after lyophilization. • LacZ expression of the developed cationic liposomes is approximately equal to the Lipofectamine® 2000.

  3. Applicator for in-vitro ultrasound-activated targeted drug delivery

    Science.gov (United States)

    Gerold, B.; Gourevich, D.; Volovick, A.; Xu, D.; Arditti, F.; Prentice, P.; Cochran, S.; Gnaim, J.; Medan, Y.; Wang, L.; Melzer, A.

    2012-10-01

    Reducing toxicity and improving uptake of cancer drugs in tumors are important goals of targeted drug delivery (TDD). Ultrasonic drug release from various encapsulants has been a focus of many research groups. However, a single standard ultrasonic device, viable for use by biologists, is not currently present in the market. The device reported here is designed to allow investigation of the impact of ultrasound on cellular uptake and cell viability in-vitro. In it, single-element transducers with different operating frequencies are mounted below a standard 96-well plate. The plate is moved above the transducers, such that each line of wells can be sonicated at a different frequency. To assess the device, 96-well plates were seeded with cells and sonicated using different ultrasonic parameters, with and without doxorubicin. Cell viability was measured by colorimetric MTT assay and the uptake of doxorubicin by cells was also determined. The device proved to be highly viable in preliminary tests; it demonstrated that change in ultrasonic parameters produces different effect on cells. For example, increase in uptake of doxorubicin was demonstrated following ultrasound application. The growing interest in ultrasound-activated TDD emphasizes the need for standardization of the ultrasound device and the one reported here may offer some indications of how that may be achieved. It is planned to further improve the prototype by increasing the number of ultrasonic frequencies and degrees of freedom for each transducer.

  4. The application of drug delivery system about nanoparticles in nuclear medicine

    International Nuclear Information System (INIS)

    Yao Ning; Wang Rongfu

    2013-01-01

    The development of nuclear medicine relies on the advancement of precise probes at the cellular and molecular levels. Nanoparticle as a new molecular probe, is mainly consists of the targeting groups, imaging groups, the superb biocompatible 'shells' and the modify groups. These nanoparticles have the better image contrast by targeting positioning in the target tissues and cells. At the same time, because of the diversity of the materials and the uniqueness of the structures, the nanoparticles can realize multimodal imaging at molecular level, which complement each other's advantages of different imaging modals. If the treatment groups are joined into the nanoparticles, a new nanoparticles are formed-the theranosis nanoparticles, which have realized the diagnosis and therapy at the molecular level synchronously. In addition, the application of intelligent nanoprobes can achieve the smart control of drug release and reduce the side effects of cancer treatment. Anyhow, the development of this new drug delivery system about nanoparticles has brought about a new breakthrough on the nuclear medicine. (authors)

  5. Last Mile Towards Efficient Healthcare Delivery in Switzerland: eHealth Enabled Applications Could Speed Up the Care Process.

    Science.gov (United States)

    Deng, Yihan; Bürkle, Thomas; Holm, Jürgen; Zetz, Erwin; Denecke, Kerstin

    2018-01-01

    A precise and timely care delivery depends on an efficient triage performed by primary care providers and smooth collaboration with other medical specialities. In recent years telemedicine gained increasing importance for efficient care delivery. It's use, however, has been limited by legal issues, missing digital infrastructures, restricted support from health insurances and the digital divide in the population. A new era towards eHealth and telemedicine starts with the establishment of national eHealth regulations and laws. In Switzerland, a nation-wide digital infrastructure and electronic health record will be established. But appropriate healthcare apps to improve patient care based on this infrastructure remain rare. In this paper, we present two applications (self-anamnesis and eMedication assistant) for eHealth enabled care delivery which have the potential to speed up diagnosis and treatment.

  6. Application of a drug delivery system using ultrasound and nano/microbubbles for anti-angiogenic therapy

    International Nuclear Information System (INIS)

    Horie, Sachiko; Kodama, Tetsuya; Sato, Yasushi

    2017-01-01

    The drug delivery system using ultrasound and nano/microbubbles is a molecular delivery approach using the mechanism of sonoporation. With sonoporation, an endothelium-derived negative-feedback regulator of angiogenesis, Vasohibin-1 (VASH1), was introduced specifically into tumor vessels. We found VASH1 in tumor vessels induce normalization of tumor vessels and inhibited tumor growth. A recent topic regarding tumor angiogenesis is vascular normalization. Tumor vessels are abnormal or immature that cause hyperpermeability and impaired blood flow. Tumor vascular normalization improves blood flow and tissue hypoxia, which increase the effectiveness of chemotherapy and radiotherapy and reduce tumor cell malignancy. In this review, application of drug delivery system using ultrasound for an anti-angiogenic therapy, a tumor vessel normalization therapy to treat cancer, is summarized. (author)

  7. Nanowires: properties, applications and synthesis via porous anodic ...

    Indian Academy of Sciences (India)

    Moreover, periodic arrays of magnetic nanowires hold high potential for recording media application. Nanowires are also potential candidates for sensor and bio-medical applications. In the present article, the physical and chemical properties of nanowires along with their probable applications in different fields have been ...

  8. Pegylated and amphiphilic Chitosan coated manganese ferrite nanoparticles for pH-sensitive delivery of methotrexate: Synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Karimi, Z. [Department of materials Engineering, Institute of Mechanical Engineering, University of Tabriz, Tabriz 51666-16471 (Iran, Islamic Republic of); Abbasi, S. [Department of Pharmaceutics, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz (Iran, Islamic Republic of); Shokrollahi, H., E-mail: shokrollahi@sutech.ac.ir [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Yousefi, Gh., E-mail: ghyousefi@sums.ac.ir [Department of Pharmaceutics, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz (Iran, Islamic Republic of); Center for Nanotechnology in Drug Delivery, Shiraz University of Medical Sciences, Shiraz (Iran, Islamic Republic of); Fahham, M. [Electroceramics Group, Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Karimi, L. [Materials Science and Engineering Department, Islamic Azad University Ahvaz Branch, Ahvaz (Iran, Islamic Republic of); Firuzi, O. [Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz (Iran, Islamic Republic of)

    2017-02-01

    Magnetic nanoparticles (MNPs) are the major class of nanoparticles (NPs) with specific functional properties that make them good candidates for biomedical applications. Due to their response to the magnetic field, they can be used in targeted drug delivery systems. In current research, the MNPs were synthesized with the general formula of Fe{sub 1−x}Mn{sub x}Fe{sub 2}O{sub 4} by the co-precipitation technique. First, the effect of the Fe{sup 2+} ions in the system was investigated. Succinic anhydride was used as the first stabilizer to prepare surface for binding two types of polymer, including Polyethylene glycol (PEG) and palmitoylated Polyethylene glycol-grafted Chitosan (Cs-PEG-PA) were introduced as a polymeric shell. The composition, size, structure and magnetic properties of NPs were determined by the particle size analysis (PSA), X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). Determining the well-defined properties of MNPs, methotrexate (MTX), as a common anticancer drug, was encapsulated into the coated MNPs. The drug encapsulation efficiency was as high as 92.8% with the magnetization value of 19.7 emu/g. The in-vitro release pattern was studied, showing only 6% of the drug release in pH = 7.4 (as a model of the physiological environment) and 25% in pH = 5.4 (as a model of the tumor tissue environment) after 72 h. Based on these results, we may be able to introduce this specific system as a novel pH sensitive MNP system for MTX targeting to tumor tissues in cancer chemotherapy. - Highlights: • Magnetic and structural studies of Fe{sub 1−x}Mn{sub x}Fe{sub 2}O{sub 4} are investigated. • Simple co-precipitation method involving less energy and low-cost is used. • Superparamagnetic particles with high magnetization and low coercivity are obtained. • The highest amount of MTX loading is related to S-Fe{sub 0.3}Mn{sub 0.7}Fe{sub 2}O{sub 4}-Cs-PEG-PA-MTX (1:1).

  9. Synthesis and characterization of multifunctional hybrid-polymeric nanoparticles for drug delivery and multimodal imaging of cancer

    Directory of Open Access Journals (Sweden)

    Tng DJH

    2015-09-01

    Full Text Available Danny Jian Hang Tng,1,* Peiyi Song,1,* Guimiao Lin,2,3,* Alana Mauluidy Soehartono,1 Guang Yang,1 Chengbin Yang,1 Feng Yin,1 Cher Heng Tan,4 Ken-Tye Yong1 1School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore; 2The Engineering Lab of Synthetic Biology, 3Research Institute of Uropoiesis and Reproduction, School of Medicine, Shenzhen University, Shenzhen, People’s Republic of China; 4Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore *These authors contributed equally to this work Abstract: In this study, multifunctional hybrid-polymeric nanoparticles were prepared for the treatment of cultured multicellular tumor spheroids (MCTS of the PANC-1 and MIA PaCa-2 pancreatic carcinoma cell lines. To synthesize the hybrid-polymeric nanoparticles, the poly lactic-co-glycolic acid core of the particles was loaded with Rhodamine 6G dye and the chemotherapeutic agent, Paclitaxel, was incorporated into the outer phospholipid layer. The surface of the nanoparticles was coated with gadolinium chelates for magnetic resonance imaging applications. This engineered nanoparticle formulation was found to be suitable for use in guided imaging therapy. Specifically, we investigated the size-dependent therapeutic response and the uptake of nanoparticles that were 65 nm, 85 nm, and 110 nm in size in the MCTS of the two pancreatic cancer cell lines used. After 24 hours of treatment, the MCTS of both PANC-1 and MIA PaCa-2 cell lines showed an average increase in the uptake of 18.4% for both 65 nm and 85 nm nanoparticles and 24.8% for 110 nm nanoparticles. Furthermore, the studies on therapeutic effects showed that particle size had a slight influence on the overall effectiveness of the formulation. In the MCTS of the MIA PaCa-2 cell line, 65 nm nanoparticles were found to produce the greatest therapeutic effect, whereas 12.8% of cells were apoptotic of which 11.4% of cells were apoptotic for 85

  10. Novel Flame-Based Synthesis of Nanowires for Multifunctional Application

    Science.gov (United States)

    2015-05-13

    pattern (SAED) of SnO2/WO2.9 heterojunction for case 7. TEM (Fig. 14(a)) reveals that the coating on the tungsten- oxide nanowires is actually a...tungsten oxide nanowire,s resulting in radial growth of Zn2SnO4 nanocube/WO2.9 nanowire heterojunction . Furthermore, the combined flame and solution...SECURITY CLASSIFICATION OF: Progress for the project has been made in various areas. Specifically, we report on: (i) flame synthesis of metal- oxide

  11. Synthesis of new porphyrinoids for biomedical and materials applications

    Science.gov (United States)

    Stewart, Fraser

    The facile synthesis of three non-hydrolysable thioglycosylated porphyrinoids is reported. Starting from meso perfluorophenylporphyrin (TPPF20), the non-hydrolysable thioglycosylated porphyrin (PGlc4), chlorin (CGlc4), isobacteriochlorin (IGlc4), and bacteriochlorin (BGlc4) can be made in 2-3 steps. The ability to append a wide range of targeting agents onto the perfluorophenyl moieties, the chemical stability, and the ability to fine-tune the photophysical properties of the chromophores make this a suitable platform for development of biochemical tags, diagnostics, or as photodynamic therapeutic agents. With reduction of one or two pyrrole double bonds, there is a red shift in the lowest energy absorption band and a significant increase in intensity. The fluorescence of these porphyrinoids is in the order PGlc4 = BGlc4 spectroscopy (DOSY) in solution. The hydrocarbon chains on the melamine mediate the formation of nanofilms on surfaces as the solvent slowly evaporates. A water soluble zinc (II) phthalocyanine symmetrically appended with eight thioglucose units was synthesized from commercially available hexadecafluoro-phthalocyaninato zinc(II) by controlled nucleophilic substitution of the peripheral fluoro groups by thio-sugars. The photophysical properties and cancer cell uptake studies of this nonhydrolyzable thioglycosylated phthalocyanine are reported. The new compound has amphiphilic character, is chemically and photochemically stable, and can potentially be used as a photosensitizer in photodynamic therapy. A porphyrin bearing pyridyl groups at the meso positions was synthesized using 2,6-diacetamido-4-formylpyridine. A new method has been developed for the synthesis of the precursor aldehyde that avoid much of the problems associated with the earlier synthesis. With this porphyrin it is possible to build hetero-complementary rigid, multi-porphyrin supramolecular arrays via hydrogen bonds. For example, when using naphthalenediimide (NDI) units a

  12. Setup for demonstrating interactive binaural synthesis for telepresence applications

    DEFF Research Database (Denmark)

    Madsen, Esben; Olesen, Søren Krarup; Markovic, Milos

    2011-01-01

    position Totem with a single loudspeaker. The Position and movements of participants, particularly the head, are tracked and from this sound is rendered to include binaural cues so the Visitor is able to move around in a limited space while perceiving Destination sound as "stationary". This setup includes......, latency and transmission reliablity must be adjusted to obtain the best compromise. Bandwidth use and reliablity can be improved at the cost of latency. Finally the binaural synthesis for each source is processed at the listener's site (here Visitor) to have a minimum latency on responding to movement...

  13. Development of novel drug delivery systems using phage display technology for clinical application of protein drugs.

    Science.gov (United States)

    Nagano, Kazuya; Tsutsumi, Yasuo

    2016-01-01

    Attempts are being made to develop therapeutic proteins for cancer, hepatitis, and autoimmune conditions, but their clinical applications are limited, except in the cases of drugs based on erythropoietin, granulocyte colony-stimulating factor, interferon-alpha, and antibodies, owing to problems with fundamental technologies for protein drug discovery. It is difficult to identify proteins useful as therapeutic seeds or targets. Another problem in using bioactive proteins is pleiotropic actions through receptors, making it hard to elicit desired effects without side effects. Additionally, bioactive proteins have poor therapeutic effects owing to degradation by proteases and rapid excretion from the circulatory system. Therefore, it is essential to establish a series of novel drug delivery systems (DDS) to overcome these problems. Here, we review original technologies in DDS. First, we introduce antibody proteomics technology for effective selection of proteins useful as therapeutic seeds or targets and identification of various kinds of proteins, such as cancer-specific proteins, cancer metastasis-related proteins, and a cisplatin resistance-related protein. Especially Ephrin receptor A10 is expressed in breast tumor tissues but not in normal tissues and is a promising drug target potentially useful for breast cancer treatment. Moreover, we have developed a system for rapidly creating functional mutant proteins to optimize the seeds for therapeutic applications and used this system to generate various kinds of functional cytokine muteins. Among them, R1antTNF is a TNFR1-selective antagonistic mutant of TNF and is the first mutein converted from agonist to antagonist. We also review a novel polymer-conjugation system to improve the in vivo stability of bioactive proteins. Site-specific PEGylated R1antTNF is uniform at the molecular level, and its bioactivity is similar to that of unmodified R1antTNF. In the future, we hope that many innovative protein drugs will be

  14. Preparation of magnetic nanoparticles and their application to magnetic targeting drug delivery

    International Nuclear Information System (INIS)

    Li Guiping; Wang Yongxian

    2006-01-01

    Magnetic nanoparticles barrier is a novel kind of drug delivery system for magnetic targeting drugs, which can effectively deliver the drug to a tumor target site and increase therapeutic benefit, with the side effects minimized. This article summarizes the most outstanding papers on the of magnetic nanoparticles used as the targeting drug's delivery systems. (authors)

  15. Application of a GIS-BIOLOCO tool for the design and assessment of biomass delivery chains

    NARCIS (Netherlands)

    Geijzendorffer, I.R.; Annevelink, E.; Elbersen, B.S.; Smidt, R.A.; Mol, de R.M.

    2008-01-01

    The spatial fragmentation of different biomass sources in one or more regions makes design and assessment of sustainable biomass delivery chains rather complicated. This paper presents a GIS tool that supports the design and facilitates a sustainability assessment of biomass delivery chains at a

  16. Synthesis, fabrication and characterisation of zinc oxide nanostructures for biomimetic, drug delivery and biosensing applications

    OpenAIRE

    Syed, Atif

    2017-01-01

    A successful cancer treatment is a combination of early diagnosis and efficient use of anticancer drugs. There is a chance of approximately 70 - 90% of cancer patients surviving if the diagnosis is conducted early. That means if a diagnosis system is in place which can detect multiple types of cancer at an early stage, a potential cancer therapy is most likely to succeed. However, at present, the available biomedical sensors are unable to detect and differentiate between cancerous...

  17. Synthesis, cellular delivery and In vivo application of dendrimer-based pH sensors

    NARCIS (Netherlands)

    Albertazzi, L.; Storti, B.; Brondi, M.; Sato, S.S.; Ratto, G.M.; Signore, G.; Beltram, F.

    The development of fluorescent indicators represented a revolution for life sciences. Genetically encoded and synthetic fluorophores with sensing abilities allowed the visualization of biologically relevant species with high spatial and temporal resolution. Synthetic dyes are of particular interest

  18. Synthesis and characterization of bioresorbable calcium phosphosilicate nanocomposite particles for fluorescence imaging and biomedical applications

    Science.gov (United States)

    Morgan, Thomas T.

    Organically doped calcium phosphosilicate nanoparticles (CPSNPs) were developed and characterized, driven by the need for non-toxic vectors for drug delivery and fluorescence biological imaging applications. In particular, advancement in drug delivery for the chemotherapeutic treatment of cancers is required to increase drug efficacy and improve patient quality of life. Additionally, brighter and more photostable fluorophores are needed to meet demands for improved sensitivity and experimental diversity, which may lead to improvements in early detection of solid tumors and advancement in understanding of biological processes. A literature survey on the state of the field for nanoparticle based biological fluorescence imaging and drug delivery is presented in Chapter 1. Chapter 2 focuses on the characterization techniques used in this work. The development and optical characterization of 20-40 nm diameter, citrate functionalized Cy3 amidite doped calcium phosphosilicate nanoparticles (Cy3 CPSNPs) for in vitro fluorescence imaging is outlined in Chapters 3 and 4, respectively. In particular, sodium citrate was used to functionalize the surface and provide electrosteric dispersion of these particles. CPSNPs stabilized with sodium citrate routinely exhibited highly negative zeta potentials greater than -25 mV in magnitude. Furthermore, the fluorescence quantum yield of the encapsulated fluorophore was improved by more than 4.5-fold when compared to the unencapsulated dye. The bioimaging and drug delivery capability of CPSNPs was explored. Cy3 CPSNPs dissolved quickly in the acidic environment experienced during endocytosis, releasing the encapsulated fluorophore. This is consistent with solution phase experiments that show the particles are dissolved at pH 5. CPSNPs loaded with fluorescein and a hydrophobic growth inhibitor, ceramide C6, proved the ability to simultaneously image and delivery of the hydrophobic drug to cells in vitro. Chapter 5 examined the colloidal

  19. Silver nanoparticles: mechanism of antimicrobial action, synthesis, medical applications, and toxicity effects

    Science.gov (United States)

    Prabhu, Sukumaran; Poulose, Eldho K.

    2012-10-01

    Silver nanoparticles are nanoparticles of silver which are in the range of 1 and 100 nm in size. Silver nanoparticles have unique properties which help in molecular diagnostics, in therapies, as well as in devices that are used in several medical procedures. The major methods used for silver nanoparticle synthesis are the physical and chemical methods. The problem with the chemical and physical methods is that the synthesis is expensive and can also have toxic substances absorbed onto them. To overcome this, the biological method provides a feasible alternative. The major biological systems involved in this are bacteria, fungi, and plant extracts. The major applications of silver nanoparticles in the medical field include diagnostic applications and therapeutic applications. In most of the therapeutic applications, it is the antimicrobial property that is being majorly explored, though the anti-inflammatory property has its fair share of applications. Though silver nanoparticles are rampantly used in many medical procedures and devices as well as in various biological fields, they have their drawbacks due to nanotoxicity. This review provides a comprehensive view on the mechanism of action, production, applications in the medical field, and the health and environmental concerns that are allegedly caused due to these nanoparticles. The focus is on effective and efficient synthesis of silver nanoparticles while exploring their various prospective applications besides trying to understand the current scenario in the debates on the toxicity concerns these nanoparticles pose.

  20. Gas-phase plasma synthesis of free-standing silicon nanoparticles for future energy applications

    NARCIS (Netherlands)

    Doğan, I.; van de Sanden, M.C.M.

    2016-01-01

    Silicon nanoparticles (Si-NPs) are considered as possible candidates for a wide spectrum of future technological applications. Research in the last decades has shown that plasmas are one of the most suitable environments for the synthesis of Si-NPs. This review discusses the unique size-dependent

  1. Gas-Phase Plasma Synthesis of Free-Standing Silicon Nanoparticles for Future Energy Applications

    NARCIS (Netherlands)

    Dogan, I.; van de Sanden, M. C. M.

    2016-01-01

    Silicon nanoparticles (Si-NPs) are considered as possible candidates for a wide spectrum of future technological applications. Research in the last decades has shown that plasmas are one of the most suitable environments for the synthesis of Si-NPs. This review discusses the unique size-dependent

  2. Certified policy synthesis for general Markov decision processes : an application in building automation systems

    NARCIS (Netherlands)

    Haesaert, S.; Cauchi, N.; Abate, A.

    2017-01-01

    In this paper, we present an industrial application of new approximate similarity relations for Markov models, and show that they are key for the synthesis of control strategies. Typically, modern engineering systems are modelled using complex and high-order models which make the correct-by-design

  3. Predicting when precipitation-driven synthesis is feasible : application to biocatalysis

    NARCIS (Netherlands)

    Ulijn, R.V.; Janssen, A.E.M.; Moore, B.D.; Halling, P.J.

    2001-01-01

    Precipitation-driven synthesis offers the possibility of obtaining high reaction yields using very low volume reactors and is finding increasing applications in biocatalysis. Here, a model that allows straightforward prediction of when such a precipitation-driven reaction will be thermodynamically

  4. Self-assembled M2L4 coordination cages : Synthesis and potential applications

    NARCIS (Netherlands)

    Schmidt, Andrea; Casini, Angela; Kuehn, Fritz E.

    2014-01-01

    Metal-mediated self-assemblies of the general formula MxLy (M = metal ion, L = ligand) have emerged as a promising research area of supramolecular chemistry because of their applicability in various fields such as molecular recognition, catalysis and drug delivery. The focus of this review is on

  5. Sol–gel one-pot synthesis in soft conditions of mesoporous silica materials ready for drug delivery system

    NARCIS (Netherlands)

    Tourne-Peteilh, C.; Begu, S.; Lerner, D.A.; Galarneau, A.; Lafont, U.; Devoiselle, J.M.

    2011-01-01

    The present work reveals a new and simple strategy, a one-step sol–gel procedure, to encapsulate a low water-soluble drug in silica mesostructured microparticles and to improve its release in physiological media. The synthesis of these new materials is based on the efficient solubilisation of a

  6. Nanotechnology and Drug Delivery Part 1: Background and ...

    African Journals Online (AJOL)

    Nanotechnology in general and as it relates to drug delivery in humans has been reviewed in a two-part article, the first part of which is this paper. In this paper, nanotechnology in nature, history of nanotechnology and methods of synthesis are discussed, while also outlining its applications, benefits and risks.

  7. Core-shell designs of photoluminescent nanodiamonds with porous silica coatings for bioimaging and drug delivery II: application.

    Science.gov (United States)

    Prabhakar, Neeraj; Näreoja, Tuomas; von Haartman, Eva; Karaman, Didem Şen; Jiang, Hua; Koho, Sami; Dolenko, Tatiana A; Hänninen, Pekka E; Vlasov, Denis I; Ralchenko, Victor G; Hosomi, Satoru; Vlasov, Igor I; Sahlgren, Cecilia; Rosenholm, Jessica M

    2013-05-07

    Recent advances within materials science and its interdisciplinary applications in biomedicine have emphasized the potential of using a single multifunctional composite material for concurrent drug delivery and biomedical imaging. Here we present a novel composite material consisting of a photoluminescent nanodiamond (ND) core with a porous silica (SiO2) shell. This novel multifunctional probe serves as an alternative nanomaterial to address the existing problems with delivery and subsequent tracing of the particles. Whereas the unique optical properties of ND allows for long-term live cell imaging and tracking of cellular processes, mesoporous silica nanoparticles (MSNs) have proven to be efficient drug carriers. The advantages of both ND and MSNs were hereby integrated in the new composite material, ND@MSN. The optical properties provided by the ND core rendered the nanocomposite suitable for microscopy imaging in fluorescence and reflectance mode, as well as super-resolution microscopy as a STED label; whereas the porous silica coating provided efficient intracellular delivery capacity, especially in surface-functionalized form. This study serves as a demonstration how this novel nanomaterial can be exploited for both bioimaging and drug delivery for future theranostic applications.

  8. Liquid phase oxidation via heterogeneous catalysis organic synthesis and industrial applications

    CERN Document Server

    Clerici, Mario G

    2013-01-01

    Sets the stage for environmentally friendly industrial organic syntheses From basic principles to new and emerging industrial applications, this book offers comprehensive coverage of heterogeneous liquid-phase selective oxidation catalysis. It fully examines the synthesis, characterization, and application of catalytic materials for environmentally friendly organic syntheses. Readers will find coverage of all the important classes of catalysts, with an emphasis on their stability and reusability. Liquid Phase Oxidation via Heterogeneous Catalysis features contributions from an internation

  9. Synthesis and Characterization of Calcium Phosphate Powders for Biomedical Applications by Plasma Spray Coating

    OpenAIRE

    Sasidharan Pillai, Rahul

    2015-01-01

    This PhD work mainly focus on the synthesis and characterization of calcium phosphate powders for plasma spray coating. The preparation of high temperature phase stabilized βTCP and HA/βTCP powders for plasma spray coating applications has been the topic of investigation. Nowadays plasma sprayed coatings are widely used for biomedical applications especially in the dental and orthopaedic implantation field. Previously Ti based alloys were widely used for the orthopaedic and dental implant ap...

  10. Quantum dots–DNA bioconjugates: synthesis to applications

    Science.gov (United States)

    2016-01-01

    Semiconductor nanoparticles particularly quantum dots (QDs) are interesting alternatives to organic fluorophores for a range of applications such as biosensing, imaging and therapeutics. Addition of a programmable scaffold such as DNA to QDs further expands the scope and applicability of these hybrid nanomaterials in biology. In this review, the most important stages of preparation of QD–DNA conjugates for specific applications in biology are discussed. Special emphasis is laid on (i) the most successful strategies to disperse QDs in aqueous media, (ii) the range of different conjugation with detailed discussion about specific merits and demerits in each case, and (iii) typical applications of these conjugates in the context of biology. PMID:27920898

  11. Enhancing the transdermal delivery of rigid nanoparticles using the simultaneous application of ultrasound and sodium lauryl sulfate.

    Science.gov (United States)

    Lopez, Renata F V; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert

    2011-01-01

    The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ∼0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500-1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Aperture Synthesis Methods and Applications to Optical Astronomy

    CERN Document Server

    Saha, Swapan Kumar

    2011-01-01

    Over the years long baseline optical interferometry has slowly gained in importance and today it is a powerful tool. This timely book sets out to highlight the basic principles of long baseline optical interferometry. The book addresses the fundamentals of stellar interferometry with emphasis on aperture synthesis using an array of telescopes particularly at optical/IR wavelengths. It discusses the fundamentals of electromagnetic fields, wave optics, interference, diffraction, and imaging at length. There is a chapter dedicated to radio and intensity interferometry corroborating with basic mathematical steps. The basic principle of optical interferometry and its requirements, its limitations and the technical challenges it poses, are also covered in depth. Assisted by illustrations and footnotes, the book examines the basic tricks of the trade, current trends and methods, and it points to the potential of true interferometry both from the ground and space.

  13. Evolutionary population synthesis - An application to Magellanic Cloud clusters

    International Nuclear Information System (INIS)

    Battinelli, P.; Capuzzo-Dolcetta, R.

    1989-01-01

    Synthetic models are computed in order to study the evolution with time of integrated luminosities and colors for stellar systems spanning ranges of total mass and metal abundance similar to those characteristic of the Small and Large Magellanic Clouds (SMC and LMC) globular-like clusters. General aspects of this synthetic approach, results relative to the integral bolometric and U, B, V fluxes and colors, and indications on the reliability of photometric synthesis in giving informations on the stellar content of star clusters are discussed. A picture for the formation and evolution of the Cloud clusters is discussed on the basis of the comparison between theory and observations. In particular, an evaluation of the masses for a sample of MC clusters based on the models is given, a discussion of the problem of the gap in the integral color distributions is reported, and a possible solution on the basis of the synthetic models is suggested. 114 refs

  14. Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis

    Science.gov (United States)

    2016-01-01

    The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the involvement of electronically excited states, generated upon absorption of photons. This produces transient reactive intermediates and significantly alters the reactivity of a chemical compound. The input of energy provided by light thus offers a means to produce strained and unique target compounds that cannot be assembled using thermal protocols. This review aims at highlighting photochemical transformations as a tool for rapidly accessing structurally and stereochemically diverse scaffolds. Synthetic designs based on photochemical transformations have the potential to afford complex polycyclic carbon skeletons with impressive efficiency, which are of high value in total synthesis. PMID:27120289

  15. Methane synthesis under mild conditions for decentralized applications

    International Nuclear Information System (INIS)

    Schlueter, Michael; Roensch, Stefan

    2016-01-01

    It is a central aim of the German government to significantly reduce the emission of greenhouse gases in the next years. One possibility to reach this aim is the substitution of fossil fuels, especially natural gas, by fuels from biogenic sources (Bio-SNG). However, it is a drawback of Bio-SNG that the production costs are considerably higher than those of fossil natural gas. This work provides an approach to reduce the production costs of Bio-SNG. It is the aim to reduce the process parameters of the methane synthesis. At the same time, it has to be ensured that high methane yields are achieved even at those mild conditions. A procedure for the optimization of the methanation catalyst activity will be presented. If the catalyst is as active as possible even at mild conditions, it will be possible to produce Bio-SNG cost efficient even in small, decentralized scale.

  16. Electrospun Ceramic Nanofiber Mats Today: Synthesis, Properties, and Applications

    Science.gov (United States)

    Esfahani, Hamid; Ramakrishna, Seeram

    2017-01-01

    Ceramic nanofibers (NFs) have recently been developed for advanced applications due to their unique properties. In this article, we review developments in electrospun ceramic NFs with regard to their fabrication process, properties, and applications. We find that surface activity of electrospun ceramic NFs is improved by post pyrolysis, hydrothermal, and carbothermal processes. Also, when combined with another surface modification methods, electrospun ceramic NFs result in the advancement of properties and widening of the application domains. With the decrease in diameter and length of a fiber, many properties of fibrous materials are modified; characteristics of such ceramic NFs are different from their wide and long (bulk) counterparts. In this article, electrospun ceramic NFs are reviewed with an emphasis on their applications as catalysts, membranes, sensors, biomaterials, fuel cells, batteries, supercapacitors, energy harvesting systems, electric and magnetic parts, conductive wires, and wearable electronic textiles. Furthermore, properties of ceramic nanofibers, which enable the above applications, and techniques to characterize them are briefly outlined. PMID:29077074

  17. Electrospun Ceramic Nanofiber Mats Today: Synthesis, Properties, and Applications

    Directory of Open Access Journals (Sweden)

    Hamid Esfahani

    2017-10-01

    Full Text Available Ceramic nanofibers (NFs have recently been developed for advanced applications due to their unique properties. In this article, we review developments in electrospun ceramic NFs with regard to their fabrication process, properties, and applications. We find that surface activity of electrospun ceramic NFs is improved by post pyrolysis, hydrothermal, and carbothermal processes. Also, when combined with another surface modification methods, electrospun ceramic NFs result in the advancement of properties and widening of the application domains. With the decrease in diameter and length of a fiber, many properties of fibrous materials are modified; characteristics of such ceramic NFs are different from their wide and long (bulk counterparts. In this article, electrospun ceramic NFs are reviewed with an emphasis on their applications as catalysts, membranes, sensors, biomaterials, fuel cells, batteries, supercapacitors, energy harvesting systems, electric and magnetic parts, conductive wires, and wearable electronic textiles. Furthermore, properties of ceramic nanofibers, which enable the above applications, and techniques to characterize them are briefly outlined.

  18. Recent advances in synthesis of bacterial rare sugar building blocks and their applications.

    Science.gov (United States)

    Emmadi, Madhu; Kulkarni, Suvarn S

    2014-07-01

    Covering: 1964 to 2013. Bacteria have unusual glycans on their surfaces which distinguish them from the host cells. These unique structures offer avenues for targeting bacteria with specific therapeutics and vaccine. However, these rare sugars are not accessible in acceptable purity and amounts by isolation from natural sources. Thus, procurement of orthogonally protected rare sugar building blocks through efficient chemical synthesis is regarded as a crucial step towards the development of glycoconjugate vaccines. This Highlight focuses on recent advances in the synthesis of the bacterial deoxy amino hexopyranoside building blocks and their application in constructing various biologically important bacterial O-glycans.

  19. Synthesis and application of a new fluorous-tagged ammonia equivalent.

    Science.gov (United States)

    Nielsen, Simon D; Smith, Garrick; Begtrup, Mikael; Kristensen, Jesper L

    2010-04-19

    A novel fluorous-tagged ammonia equivalent has been developed. It is based on a nitrogen-oxygen bond, which can be cleaved in a traceless manner by a molybdenum complex or samarium diiodide. The application in the synthesis of ureas, amides, sulfonamides, and carbamates is described. The scope of the fluorous N-O linker is exemplified by the synthesis of itopride, a drug used for the treatment of functional dyspepsia. Itopride was synthesized with the aid of fluorous purification methods and the product was isolated in good overall yield, with high purity. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Synthesis and application of a new fluorous-tagged ammonia equivalent

    DEFF Research Database (Denmark)

    Nielsen, Simon Dalsgaard; Smith, Garrick; Begtrup, Mikael

    2010-01-01

    A novel fluorous-tagged ammonia equivalent has been developed. It is based on a nitrogen-oxygen bond, which can be cleaved in a traceless manner by a molybdenum complex or samarium diiodide. The application in the synthesis of ureas, amides, sulfonamides, and carbamates is described. The scope of...... of the fluorous N--O linker is exemplified by the synthesis of itopride, a drug used for the treatment of functional dyspepsia. Itopride was synthesized with the aid of fluorous purification methods and the product was isolated in good overall yield, with high purity....

  1. Facile synthesis and application of a carbon foam with large mesopores

    KAUST Repository

    Fu, Liling

    2013-01-01

    By combining elements of hard- and soft-templating, a facile synthesis method for carbon foams with large mesopores has been demonstrated. A commercial Pluronic surfactant was used as the structure-directing agent as well as the carbon precursor. No micelle swelling agent or post treatment is necessary to enlarge mesopores. As such this method requires fewer synthesis steps and is highly scalable. The as-synthesized meso-carbons showed potential applications in the fields of carbon oxide capture and lithium-sulfur batteries. © 2013 the Owner Societies.

  2. Synthesis and evaluation of temperature- and glucose-sensitive nanoparticles based on phenylboronic acid and N-vinylcaprolactam for insulin delivery

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jun-zi [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620 (China); Bremner, David H. [School of Science, Engineering and Technology, Kydd Building, Abertay University, Dundee DD1 1HG, Scotland (United Kingdom); Li, He-yu; Sun, Xiao-zhu [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620 (China); Zhu, Li-Min, E-mail: lzhu@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620 (China)

    2016-12-01

    Poly N-vinylcaprolactam-co-acrylamidophenylboronic acid p(NVCL-co-AAPBA) was prepared from N-vinylcaprolactam (NVCL) and 3-acrylamidophenylboronic acid (AAPBA), using 2,2-azobisisobutyronitrile (AIBN) as initiator. The synthesis and structure of the polymer were examined by Fourier Transform infrared spectroscopy (FT-IR) and {sup 1}H-NMR. Dynamic light scattering (DLS), lower critical solution temperature (LCST) and transmission electron microscopy (TEM) were utilized to characterize the nanoparticles, CD spectroscopy was used to determine if there were any changes to the conformation of the insulin, and cell and animal toxicity were also investigated. The prepared nanoparticles were found to be monodisperse submicron particles and were glucose- and temperature-sensitive. In addition, the nanoparticles have good insulin-loading characteristics, do not affect the conformation of the insulin and show low-toxicity to cells and animals. These p(NVCL-co-AAPBA) nanoparticles may have some value for insulin or other hypoglycemic protein delivery. - Highlights: • A comprehensive study of a nanoparticles may have some value for insulin or other hypoglycemic protein delivery. • p(NVCL-co-AAPBA)'s synthetic method is simple, convenient to carry out. • NVCL is low toxic and safe. • The evaluation of acute toxicity and chronic toxicity is the most highlight.

  3. Magnetic manipulation of superparamagnetic nanoparticles in a microfluidic system for drug delivery applications

    International Nuclear Information System (INIS)

    Agiotis, L.; Theodorakos, I.; Samothrakitis, S.; Papazoglou, S.; Zergioti, I.; Raptis, Y.S.

    2016-01-01

    Magnetic nanoparticles (MNPs), such as superparamagnetic iron oxide nanoparticles (SPIONS), have attracted major interest, due to their small size and unique magnetic properties, for drug delivery applications. In this context, iron oxide nanoparticles of magnetite (Fe 3 O 4 ) (150 nm magnetic core diameter), were used as drug carriers, aiming to form a magnetically controlled nano-platform. The navigation capabilities of the iron oxide nanoparticles in a microfluidic channel were investigated by simulating the magnetic field and the magnetic force applied on the magnetic nanoparticles inside a microfluidic chip. The simulations have been performed using finite element method (ANSY’S software). The optimum setup which intends to simulate the magnetic navigation of the nanoparticles, by the use of MRI-type fields, in the human circulatory system, consists of two parallel permanent magnets to produce a homogeneous magnetic field, in order to ensure the maximum magnetization of the magnetic nanoparticles, an electromagnet for the induction of the magnetic gradients and the creation of the magnetic force and a microfluidic setup so as to simulate the blood flow inside the human blood vessels. The magnetization of the superparamagnetic nanoparticles and the consequent magnetic torque developed by the two permanent magnets, together with the mutual interactions between the magnetized nanoparticles lead to the creation of rhabdoid aggregates in the direction of the homogeneous field. Additionally, the magnetic gradients introduced by the operation of the electromagnet are capable of directing the aggregates, as a whole, to the desired direction. By removing the magnetic fields, the aggregates are disrupted, due to the super paramagnetic nature of the nanoparticles, avoiding thus the formation of undesired thrombosis. - Highlights: • Homogeneous field yields an aggregation of particles along the lines of the field. • Additional electromagnet field rotates the

  4. Beam delivery system for Ho:YLF and applications in endodontics

    International Nuclear Information System (INIS)

    Bachmann, Luciano

    2000-01-01

    The beam delivery systems, whether using fibers or articulated arms, are very important for the expansion of laser applications into life sciences. This work aims to couple an optical fiber to a home-made Er:Tm:Ho:LiYF 4 laser. For this purpose the beam profile was studied using the beam quality factor M 2 to achieve an homogeneous beam. To determine the M 2 factor, the knife-edge technique was used, relating the laser energy eclipsed by the knife with its transversal position. The resonant cavity was made suitable in order to obtain a stable and homogeneous transversal beam profile, for the optical fiber coupling. It was used a 365 μm diameter core low OH - content fused silica optical fiber, with a proximal SMA-905 connection and a flat distal end. M 2 factors for the Ho:YLF were between 3 and 8, with a non astigmatic beam, although it was observed a divergence asymmetry in the transversal sections. The coupling efficiency was 96%, and in a repeated operation without any adjustment, the new coupling were 82% and 81%. Lasers have being recently used as an adjunct to conventional endodontic preparation to reduce intracanal microbial, preventing reinfection. The knowledge of thermal profile in endodontic procedures is important to determine laser irradiation conditions avoiding periodontal damages. In this sense, the second scope of this work was to use the Ho:YLF system to register the thermal profile in vitro and to compare the results with those obtained with Nd:YAG and Er:YAG commercial lasers. The temperature was recorded in real time through a thermocouple probe at the root apex , resulting in maximum increase of 7 deg C. (author)

  5. Magnetic manipulation of superparamagnetic nanoparticles in a microfluidic system for drug delivery applications

    Energy Technology Data Exchange (ETDEWEB)

    Agiotis, L.; Theodorakos, I.; Samothrakitis, S.; Papazoglou, S.; Zergioti, I.; Raptis, Y.S.

    2016-03-01

    Magnetic nanoparticles (MNPs), such as superparamagnetic iron oxide nanoparticles (SPIONS), have attracted major interest, due to their small size and unique magnetic properties, for drug delivery applications. In this context, iron oxide nanoparticles of magnetite (Fe{sub 3}O{sub 4}) (150 nm magnetic core diameter), were used as drug carriers, aiming to form a magnetically controlled nano-platform. The navigation capabilities of the iron oxide nanoparticles in a microfluidic channel were investigated by simulating the magnetic field and the magnetic force applied on the magnetic nanoparticles inside a microfluidic chip. The simulations have been performed using finite element method (ANSY’S software). The optimum setup which intends to simulate the magnetic navigation of the nanoparticles, by the use of MRI-type fields, in the human circulatory system, consists of two parallel permanent magnets to produce a homogeneous magnetic field, in order to ensure the maximum magnetization of the magnetic nanoparticles, an electromagnet for the induction of the magnetic gradients and the creation of the magnetic force and a microfluidic setup so as to simulate the blood flow inside the human blood vessels. The magnetization of the superparamagnetic nanoparticles and the consequent magnetic torque developed by the two permanent magnets, together with the mutual interactions between the magnetized nanoparticles lead to the creation of rhabdoid aggregates in the direction of the homogeneous field. Additionally, the magnetic gradients introduced by the operation of the electromagnet are capable of directing the aggregates, as a whole, to the desired direction. By removing the magnetic fields, the aggregates are disrupted, due to the super paramagnetic nature of the nanoparticles, avoiding thus the formation of undesired thrombosis. - Highlights: • Homogeneous field yields an aggregation of particles along the lines of the field. • Additional electromagnet field rotates the

  6. Long-circulating Janus nanoparticles made by electrohydrodynamic co-jetting for systemic drug delivery applications

    Science.gov (United States)

    Rahmani, Sahar; Villa, Carlos H.; Dishman, Acacia F.; Grabowski, Marika E.; Pan, Daniel C.; Durmaz, Hakan; Misra, Asish C; Colón-Meléndez, Laura; Solomon, Michael J.; Muzykantov, Vladimir R.; Lahann, Joerg

    2016-01-01

    Background Nanoparticles with controlled physical properties have been widely used for controlled release applications. In addition to shape, the anisotropic nature of the particles can be an important design criterion to ensure selective surface modification or independent release of combinations of drugs. Purpose Electrohydrodynamic (EHD) co-jetting is used for the fabrication of uniform anisotropic nanoparticles with individual compartments and initial physicochemical and biological characterization is reported. Methods EHD co-jetting is used to create nanoparticles, which are characterized at each stage with scanning electron microscopy (SEM), structured illumination microscopy (SIM), dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). Surface immobilization techniques are used to incorporate polyethylene glycol (PEG) and I125 radiolabels into the nanoparticles. Particles are injected in mice and the particle distribution after 1, 4 and 24 hours is assessed. Results and discussion Nanoparticles with an average diameter of 105.7 nm are prepared by EHD co-jetting. The particles contain functional chemical groups for further surface modification and radiolabeling. The density of PEG molecules attached to the surface of nanoparticles is determined to range between 0.02 and 6.04 ligands per square nanometer. A significant fraction of the nanoparticles (1.2% injected dose per mass of organ) circulates in the blood after 24 h. Conclusion EHD co-jetting is a versatile method for the fabrication of nanoparticles for drug delivery. Circulation of the nanoparticles for 24 h is a pre-requisite for subsequent studies to explore defined targeting of the nanoparticles to a specific anatomic site. PMID:26453170

  7. Transdermal and intradermal delivery of therapeutic agents: application of physical technologies

    National Research Council Canada - National Science Library

    Banga, Ajay K

    2011-01-01

    .... Advancements in science combined with the need for diverse drug delivery modalities have introduced a variety of transdermal and intradermal products for existing drugs at a fraction of the cost of new drug development...

  8. Applications of lipid based formulation technologies in the delivery of biotechnology-based therapeutics.

    Science.gov (United States)

    du Plessis, Lissinda H; Marais, Etienne B; Mohammed, Faruq; Kotzé, Awie F

    2014-01-01

    In the last decades several new biotechnologically-based therapeutics have been developed due to progress in genetic engineering. A growing challenge facing pharmaceutical scientists is formulating these compounds into oral dosage forms with adequate bioavailability. An increasingly popular approach to formulate biotechnology-based therapeutics is the use of lipid based formulation technologies. This review highlights the importance of lipid based drug delivery systems in the formulation of oral biotechnology based therapeutics including peptides, proteins, DNA, siRNA and vaccines. The different production procedures used to achieve high encapsulation efficiencies of the bioactives are discussed, as well as the factors influencing the choice of excipient. Lipid based colloidal drug delivery systems including liposomes and solid lipid nanoparticles are reviewed with a focus on recent advances and updates. We further describe microemulsions and self-emulsifying drug delivery systems and recent findings on bioactive delivery. We conclude the review with a few examples on novel lipid based formulation technologies.

  9. Improving the Lung Delivery of Nasally Administered Aerosols During Noninvasive Ventilation—An Application of Enhanced Condensational Growth (ECG)

    Science.gov (United States)

    Tian, Geng; Hindle, Michael

    2011-01-01

    Abstract Background Aerosol drug delivery during noninvasive ventilation (NIV) is known to be inefficient due to high depositional losses. To improve drug delivery efficiency, the concept of enhanced condensational growth (ECG) was recently proposed in which a submicrometer or nanoaerosol reduces extrathoracic deposition and subsequent droplet size increase promotes lung retention. The objective of this study was to provide proof-of-concept that the ECG approach could improve lung delivery of nasally administered aerosols under conditions consistent with NIV. Methods Aerosol deposition and size increase were evaluated in an adult nose–mouth–throat (NMT) replica geometry using both in vitro experiments and CFD simulations. For the ECG delivery approach, separate streams of a submicrometer aerosol and warm (39°C) saturated air were generated and delivered to the right and left nostril inlets, respectively. A control case was also considered in which an aerosol with a mass median aerodynamic diameter (MMAD) of 4.67 μm was delivered to the model. Results In vitro experiments showed that the ECG approach significantly reduced the drug deposition fraction in the NMT geometry compared with the control case [14.8 (1.83)%—ECG vs. 72.6 (3.7)%—control]. Aerosol size increased from an initial MMAD of 900 nm to a size of approximately 2 μm at the exit of the NMT geometry. Results of the CFD model were generally in good agreement with the experimental findings. Based on CFD predictions, increasing the delivery temperature of the aerosol stream from 21 to 35°C under ECG conditions further reduced the total NMT drug deposition to 5% and maintained aerosol growth by ECG to approximately 2 μm. Conclusions Application of the ECG approach may significantly improve the delivery of pharmaceutical aerosols during NIV and may open the door for using the nasal route to routinely deliver pulmonary medications. PMID:21410327

  10. Understanding the performance of community health volunteers involved in the delivery of health programmes in underserved areas: a realist synthesis

    OpenAIRE

    Vareilles, Ga?lle; Pommier, Jeanine; Marchal, Bruno; Kane, Sumit

    2017-01-01

    Background The recruitment of community health volunteers (CHVs) to support the delivery of health programmes is an established approach in underserved areas and in particular where there are health inequalities due to the scarcity of trained human resources. However, there is a dearth of evidence about what works to improve CHVs? performance. This review aimed to synthesise existing literature to explain why, how and under which circumstances intervention approaches to improve the performanc...

  11. Protein instability and immunogenicity: roadblocks to clinical application of injectable protein delivery systems for sustained release.

    Science.gov (United States)

    Jiskoot, Wim; Randolph, Theodore W; Volkin, David B; Middaugh, C Russell; Schöneich, Christian; Winter, Gerhard; Friess, Wolfgang; Crommelin, Daan J A; Carpenter, John F

    2012-03-01

    Protein instability and immunogenicity are two main roadblocks to the clinical success of novel protein drug delivery systems. In this commentary, we discuss the need for more extensive analytical characterization in relation to concerns about protein instability in injectable drug delivery systems for sustained release. We then will briefly address immunogenicity concerns and outline current best practices for using state-of-the-art analytical assays to monitor protein stability for both conventional and novel therapeutic protein dosage forms. Next, we provide a summary of the stresses on proteins arising during preparation of drug delivery systems and subsequent in vivo release. We note the challenges and difficulties in achieving the absolute requirement of quantitatively assessing the degradation of protein molecules in a drug delivery system. We describe the potential roles for academic research in further improving protein stability and developing new analytical technologies to detect protein degradation byproducts in novel drug delivery systems. Finally, we provide recommendations for the appropriate approaches to formulation design and assay development to ensure that stable, minimally immunogenic formulations of therapeutic proteins are created. These approaches should help to increase the probability that novel drug delivery systems for sustained protein release will become more readily available as effective therapeutic agents to treat and benefit patients. Copyright © 2011 Wiley Periodicals, Inc.

  12. "Chameleon" Macromolecules: Synthesis, Structures and Applications of Stimulus Responsive Polymers

    NARCIS (Netherlands)

    Sui, Xiaofeng

    2012-01-01

    This thesis describes the preparation and characterization of addressable responsive polymer structures and their versatile applications. Stimuli responsive polymer chains including temperature responsive poly(N-isopropylacrylamide), PNIPAM, pH responsive poly(methacrylic acid), PMAA and redox

  13. Nanocomposites: synthesis, structure, properties and new application opportunities

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Cury Camargo

    2009-03-01

    Full Text Available Nanocomposites, a high performance material exhibit unusual property combinations and unique design possibilities. With an estimated annual growth rate of about 25% and fastest demand to be in engineering plastics and elastomers, their potential is so striking that they are useful in several areas ranging from packaging to biomedical applications. In this unified overview the three types of matrix nanocomposites are presented underlining the need for these materials, their processing methods and some recent results on structure, properties and potential applications, perspectives including need for such materials in future space mission and other interesting applications together with market and safety aspects. Possible uses of natural materials such as clay based minerals, chrysotile and lignocellulosic fibers are highlighted. Being environmentally friendly, applications of nanocomposites offer new technology and business opportunities for several sectors of the aerospace, automotive, electronics and biotechnology industries.

  14. Multi-ASIP Platform Synthesis for Real-Time Applications

    DEFF Research Database (Denmark)

    Micconi, Laura; Gangadharan, Deepak; Pop, Paul

    2013-01-01

    In this paper we are interested in deriving a distributed platform, composed of heterogeneous processing elements, targeted to applications that have strict timing constraints. We consider that the platform may use multiple Application Specific Instruction Set Processors (ASIPs). An ASIP...... is synthesized and tuned for a specific set of tasks (i.e., a task cluster). During design space exploration (DSE), we evaluate each platform solution visited in terms of its cost and performance, i.e., its ability to execute the applications such that they meet their timing constraints. To determine...... if the applications are schedulable, we have to know the worst-case execution time (WCET) of each task. However, we can determine the WCETs only after the ASIPs are synthesized, which is time consuming and therefore cannot be done during DSE. To address this circular dependency (the ASIPs depend on the task...

  15. Synthesis, Characterization, and In Vitro Drug Delivery Capabilities of (Zn, Al-Based Layered Double Hydroxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Vinay J. Nagaraj

    2015-01-01

    Full Text Available There is an urgent need for the development of alternative strategies for effective drug delivery to improve the outcome of patients suffering from deadly diseases such as cancer. Nanoparticles, in particular layered double hydroxide (LDH nanoparticles, have great potential as nanocarriers of chemotherapeutic molecules. In this study, we synthesized (Zn, Al-LDH nanoparticles and report their enhanced pH-dependent stability in comparison to the commonly used (Mg, Al-LDH nanoparticles. Fluorescein isothiocyanate (FITC and valproate (VP were intercalated into (Zn, Al-LDH nanoparticles to study cellular uptake, biocompatibility, and drug delivery capabilities using cultured pancreatic adenocarcinoma BxPC3 cells. Fluorescence measurements indicated that FITC-intercalated LDH nanoparticles showed a greater degree of energy-dependent uptake rather than passive uptake by BxPC3 cells, especially at high concentrations of nanoparticles. Tetrazolium-based colorimetric assays indicated that BxPC3 cells treated with VP-intercalated LDH nanoparticles showed a significant reduction in cell viability along with about 30-fold reduction in IC50 compared to the drug alone. In contrast, the non-drug-intercalated LDH nanoparticles did not affect the cell viability indicating very low innate cytotoxicity. Our research indicates that the superior properties of (Zn, Al-LDH nanoparticles make them ideal candidates for further development as in vivo chemotherapy drug delivery agents.

  16. Structure-Processing-Property Relationship of Poly(Glycolic Acid for Drug Delivery Systems 1: Synthesis and Catalysis

    Directory of Open Access Journals (Sweden)

    Vineet Singh

    2010-01-01

    Full Text Available Till date, market is augmented with a huge number of improved drug delivery systems. The success in this area is basically due to biodegradable polymers. Although conventional systems of drug delivery utilizing the natural and semisynthetic polymers so long but synthetic polymer gains success in the controlled drug delivery area due to better degradation profile and controlled network and functionality. The polyesters are the most studied class group due the susceptible ester linkage in their backbone. The Poly(glycolic Acid (PGA, Poly(lactic acid (PLA, and Polylactide-co-glycolide (PLGA are the best profiled polyesters and are most widely used in marketed products. These polymers, however, still are having drawbacks which failed them to be used in platform technologies like matrix systems, microspheres, and nanospheres in some cases. The common problems arose with these polymers are entrapment inefficiency, inability to degrade and release drugs with required profile, and drug instability in the microenvironment of the polymers. These problems are forcing us to develop new polymers with improved physicochemical properties. The present review gave us an insight in the various structural elements of Poly(glycolic acid, polyester, with in depth study. The first part of the review focuses on the result of studies related to synthetic methodologies and catalysts being utilized to synthesize the polyesters. However the author will also focus on the effect of processing methodologies but due some constraints those are not included in the preview of this part of review.

  17. Microencapsulation of protein drugs for drug delivery: strategy, preparation, and applications.

    Science.gov (United States)

    Ma, Guanghui

    2014-11-10

    Bio-degradable poly(lactide) (PLA)/poly(lactide-glycolide) (PLGA) and chitosan microspheres (or microcapsules) have important applications in Drug Delivery Systems (DDS) of protein/peptide drugs. By encapsulating protein/peptide drugs in the microspheres, the serum drug concentration can be maintained at a higher constant value for a prolonged time, or injection formulation can be changed to orally or mucosally administered formulation. PLA/PLGA and chitosan are most often used in injection formulation and oral formulation. However, in the preparation and applications of PLA/PLGA and chitosan microspheres containing protein/peptide drugs, the problems of broad size distribution and poor reproducibility of microspheres, and deactivation of protein during the preparation, storage and release, are still big challenges. In this article, the techniques for control of the diameter of microspheres and microcapsules will be introduced at first, then the strategies about how to maintain the bioactivity of protein drugs during preparation and drug release will be reviewed and developed in our research group. The membrane emulsification techniques including direct membrane emulsification and rapid membrane emulsification processes were developed to prepare uniform-sized microspheres, the diameter of microspheres can be controlled from submicron to 100μm by these two processes, and the reproducibility of products can be guaranteed. Furthermore, compared with conventional stirring method, the big advantages of membrane emulsification process were that the uniform microspheres with much higher encapsulation efficiency can be obtained, and the release behavior can be adjusted by selecting microsphere size. Mild membrane emulsification condition also can prevent the deactivation of proteins, which frequently occurred under high shear force in mechanical stirring, sonification, and homogenization methods. The strategies for maintaining the bioactivity of protein drug were

  18. Flow chemistry to control the synthesis of nano and microparticles for biomedical applications.

    Science.gov (United States)

    Hassan, Natalia; Oyarzun-Ampuero, Felipe; Lara, Pablo; Guerrero, Simón; Cabuil, Valérie; Abou-Hassan, Ali; Kogan, Marcelo J

    2014-03-01

    In this article we review the flow chemistry methodologies for the controlled synthesis of different kind of nano and microparticles for biomedical applications. Injection mechanism has emerged as new alternative for the synthesis of nanoparticles due to this strategy allows achieving superior levels of control of self-assemblies, leading to higher-ordered structures and rapid chemical reactions. Self-assembly events are strongly dependent on factors such as the local concentration of reagents, the mixing rates, and the shear forces, which can be finely tuned, as an example, in a microfluidic device. Injection methods have also proved to be optimal to elaborate microsystems comprising polymer solutions. Concretely, extrusion based methods can provide controlled fluid transport, rapid chemical reactions, and cost-saving advantages over conventional reactors. We provide an update of synthesis of nano and microparticles such as core/shell, Janus, nanocrystals, liposomes, and biopolymeric microgels through flow chemistry, its potential bioapplications and future challenges in this field are discussed.

  19. Green Chemistry: Effect of Microwave Irradiationon Synthesis of Chitosan for Biomedical Grade Applications of Biodegradable Materials

    Directory of Open Access Journals (Sweden)

    Amri Setyawati

    2016-10-01

    Full Text Available Microwave assisted chitosan synthesis as biodegradable material for biomedical application has been done. The purpose of this research is to synthesis of chitosan with high DD and low molecular weight using microwave energy, the study of reaction conditions include parameters of power and reaction time. Chitosan was prepared by deacetylation of chitin with 60% NaOH solution. Conventional method has been done by reflux for 90minutes, resulting chitosan with DD of 79.5%, 72.6% yields and molecular weight 6051 g/mol. Green chemistry method using microwave radiation at 800 Watts for 5 minutes has produced chitosan with highest DD, yield and molecular weight of 86%, 75% and 3797 g/mole respectively. Synthesis of Chitosan by microwave radiation method can save 10x electrical energy for the reaction, also rapidly and effectively to produce chitosan with low molecular weight compared to conventional methods

  20. Synthesis and application of new polymer bound catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Fetterly, Brandon Michael [Iowa State Univ., Ames, IA (United States)

    2005-01-01

    Nitric acid has been shown to be a weak acid in acetonitrile. It is conceivable that a nitrate salt of a weakly Lewis acidic cation could furnish a ''naked'' nitrate anion as a basic catalyst in a variety of reactions in non-aqueous solvents. Such a nitrate salt could also be bound to a polymeric support via the cation, thereby allowing for reclamation and recycling of the nitrate ion. This subject is dealt with in Chapter 2, wherein my contributions consisted of performing all the reactions with the polymer supported catalyst and carrying out the experiments necessary to shed light on the reaction mechanisms. Chapter 3 contains a description of the structure and catalytic properties of an azidoproazaphosphatrane. This compound is an air-stable versatile catalyst that has proven useful not only homogeneously, but also when bound to a solid support. The synthesis of a polymer bound proazaphosphatrane containing a trivalent phosphorus is presented in Chapter 4. Such a compound has been sought after by our group for a number of years. Not only does the synthesis I have accomplished for it allow for easier separation of proazaphosphatrane catalysts from reaction mixtures, but recycling of the base is made much simpler. Proazaphosphatranes are useful homogeneous catalysts that activate atoms in other reagents, thus enhancing their reactivity. The next chapters deal with two such reactions with aldehydes and ketones, namely silylcyanations with trialkylsilylcyanides (Chapters 5 and 6) and reductions with poly(methylhydrosiloxane), in Chapter 7. In Chapter 5, Zhigang Wang performed the initial optimization and scoping of the reaction, while repetitions of the scoping experiments for reproducibility, determination of diastereomeric ratios, and experiments aimed at elucidating aspects of the mechanism were performed by me. The proazaphosphatrane coordinates to the silicon atom in both cases, thereby allowing the aforementioned reactions to proceed under