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Sample records for gold-coated iron nanoparticles

  1. Gold-coated iron nanoparticles in transparent Si3N4 matrix thin films

    Science.gov (United States)

    Sánchez-Marcos, J.; Céspedes, E.; Jiménez-Villacorta, F.; Muñoz-Martín, A.; Prieto, C.

    2013-06-01

    A new method to prepare thin films containing gold-coated iron nanoparticles is presented. The ternary Fe-Au-Si3N4 system prepared by sequential sputtering has revealed a progressive variation of microstructures from Au/Fe/Au/Si3N4 multilayers to iron nanoparticles. Microstructural characterization by transmission electron microscopy, analysis of the magnetic properties and probing of the iron short-range order by X-ray absorption spectroscopy confirm the existence of a gold-coated iron nanoparticles of 1-2 nm typical size for a specific range of iron and gold contents per layer in the transparent silicon nitride ceramic matrix.

  2. The detection of HBV DNA with gold-coated iron oxide nanoparticle gene probes

    International Nuclear Information System (INIS)

    Xi Dong; Luo Xiaoping; Lu Qianghua; Yao Kailun; Liu Zuli; Ning Qin

    2008-01-01

    Gold-coated iron oxide nanoparticle Hepatitis B virus (HBV) DNA probes were prepared, and their application for HBV DNA measurement was studied. Gold-coated iron oxide nanoparticles were prepared by the citrate reduction of tetra-chloroauric acid in the presence of iron oxide nanoparticles which were added as seeds. With a fluorescence-based method, the maximal surface coverage of hexaethiol 30-mer oligonucleotides and the maximal percentage of hybridization strands on gold-coated iron oxide nanoparticles were (120 ± 8) oligonucleotides per nanoparticle, and (14 ± 2%), respectively, which were comparable with those of (132 ± 10) and (22 ± 3%) in Au nanoparticle groups. Large network aggregates were formed when gold-coated iron oxide nanoparticle HBV DNA gene probe was applied to detect HBV DNA molecules as evidenced by transmission electron microscopy and the high specificity was verified by blot hybridization. Our results further suggested that detecting DNA with iron oxide nanoparticles and magnetic separator was feasible and might be an alternative effective method

  3. Multifunctional gold coated iron oxide core-shell nanoparticles stabilized using thiolated sodium alginate for biomedical applications.

    Science.gov (United States)

    Sood, Ankur; Arora, Varun; Shah, Jyoti; Kotnala, R K; Jain, Tapan K

    2017-11-01

    In this paper we report synthesis of aqueous based gold coated iron oxide nanoparticles to integrate the localized surface plasma resonance (SPR) properties of gold and magnetic properties of iron oxide in a single system. Iron oxide-gold core shell nanoparticles were stabilized by attachment of thiolated sodium alginate to the surface of nanoparticles. Transmission electron microscope (TEM) micrograph presents an average elementary particle size of 8.1±2.1nm. High resolution TEM (HR-TEM) and X-ray photon spectroscopy further confirms the presence of gold shell around iron oxide core. Gold coating is responsible for reducing saturation magnetization (M s ) value from ~41emu/g to ~24emu/g - in thiolated sodium alginate stabilized gold coated iron oxide core-shell nanoparticles. The drug (curcumin) loading efficiency for the prepared nanocomposites was estimated to be around 7.2wt% (72μgdrug/mg nanoparticles) with encapsulation efficiency of 72.8%. Gold-coated iron oxide core-shell nanoparticles could be of immense importance in the field of targeted drug delivery along with capability to be used as contrast agent for MRI & CT. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Magnetic relaxation switch and colorimetric detection of thrombin using aptamer-functionalized gold-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liang Guohai; Cai Shaoyu; Zhang Peng [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China); Peng Youyuan [Department of Chemistry, Quanzhou Normal University, Quanzhou 362000 (China); Chen Hui; Zhang Song [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China); Kong Jilie, E-mail: jlkong@fudan.edu.cn [Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433 (China)

    2011-03-18

    We describe a sensitive biosensing system combining magnetic relaxation switch diagnosis and colorimetric detection of human {alpha}-thrombin, based on the aptamer-protein interaction induced aggregation of Fe{sub 3}O{sub 4}-Au nanoparticles. To demonstrate the concept, gold-coated iron oxide nanoparticle was synthesized by iterative reduction of HAuCl{sub 4} onto the dextran-coated Fe{sub 3}O{sub 4} nanoparticles. The resulting core-shell structure had a flowerlike shape with pretty narrow size distribution (referred to as 'nanorose'). The two aptamers corresponding to human {alpha}-thrombin were conjugated separately to two distinct nanorose populations. Once a solution containing human {alpha}-thrombin was introduced, the nanoroses switched from a well dispersed state to an aggregated one, leading to a change in the spin-spin relaxation time (T{sub 2}) as well as the UV-Vis absorption spectra of the solution. Thus the qualitative and quantitative detection method for human {alpha}-thrombin was established. The dual-mode detection is clearly advantageous in obtaining a more reliable result; the detection range is widened as well. By using the dual-mode detection method, a detectable T{sub 2} change is observed with 1.0 nM human {alpha}-thrombin, and the detection range is from 1.6 nM to 30.4 nM.

  5. Gold-coated nanoparticles for use in biotechnology applications

    Science.gov (United States)

    Berning, Douglas E [Los Alamos, NM; Kraus, Jr., Robert H.; Atcher, Robert W [Los Alamos, NM; Schmidt, Jurgen G [Los Alamos, NM

    2009-07-07

    A process of preparing gold-coated magnetic nanoparticles is disclosed and includes forming a suspension of magnetic nanoparticles within a suitable liquid, adding an amount of a reducible gold compound and a reducing agent to the suspension, and, maintaining the suspension for time sufficient to form gold-coated magnetic nanoparticles.

  6. CD163-Macrophages Are Involved in Rhabdomyolysis-Induced Kidney Injury and May Be Detected by MRI with Targeted Gold-Coated Iron Oxide Nanoparticles.

    Science.gov (United States)

    Rubio-Navarro, Alfonso; Carril, Mónica; Padro, Daniel; Guerrero-Hue, Melanie; Tarín, Carlos; Samaniego, Rafael; Cannata, Pablo; Cano, Ainhoa; Villalobos, Juan Manuel Amaro; Sevillano, Ángel Manuel; Yuste, Claudia; Gutiérrez, Eduardo; Praga, Manuel; Egido, Jesús; Moreno, Juan Antonio

    2016-01-01

    Macrophages play an important role in rhabdomyolysis-acute kidney injury (AKI), although the molecular mechanisms involved in macrophage differentiation are poorly understood. We analyzed the expression and regulation of CD163, a membrane receptor mainly expressed by anti-inflammatory M2 macrophages, in rhabdomyolysis-AKI and developed targeted probes for its specific detection in vivo by MRI. Intramuscular injection of glycerol in mice promoted an early inflammatory response, with elevated proportion of M1 macrophages, and partial differentiation towards a M2 phenotype in later stages, where increased CD163 expression was observed. Immunohistological studies confirmed the presence of CD163-macrophages in human rhabdomyolysis-AKI. In cultured macrophages, myoglobin upregulated CD163 expression via HO-1/IL-10 axis. Moreover, we developed gold-coated iron oxide nanoparticles vectorized with an anti-CD163 antibody that specifically targeted CD163 in kidneys from glycerol-injected mice, as determined by MRI studies, and confirmed by electron microscopy and immunological analysis. Our findings are the first to demonstrate that CD163 is present in both human and experimental rhabdomyolysis-induced AKI, suggesting an important role of this molecule in this pathological condition. Therefore, the use of probes targeting CD163-macrophages by MRI may provide important information about the cellular composition of renal lesion in rhabdomyolysis.

  7. Theranostic MUC-1 aptamer targeted gold coated superparamagnetic iron oxide nanoparticles for magnetic resonance imaging and photothermal therapy of colon cancer

    DEFF Research Database (Denmark)

    Azhdarzadeh, Morteza; Atyabi, Fatemeh; Saei, Amir Ata

    2016-01-01

    Favorable physiochemical properties and the capability to accommodate targeting moieties make superparamegnetic iron oxide nanoparticles (SPIONs) popular theranostic agents. In this study, we engineered SPIONs for magnetic resonance imaging (MRI) and photothermal therapy of colon cancer cells...

  8. Efficient light extraction from GaN LEDs using gold-coated ZnO nanoparticles

    KAUST Repository

    Alhadidi, A.

    2015-11-01

    We experimentally demonstrate the effect of depositing gold-coated ZnO nanoparticles on the surface of GaN multi-quantum well LED structures. We show that this method can significantly increase the amount of extracted light.

  9. Gold coated lanthanide phosphate nanoparticles for targeted alpha generator radiotherapy.

    Directory of Open Access Journals (Sweden)

    Mark F McLaughlin

    Full Text Available Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo α-generator targeted radiotherapies can deliver multiple α particles to a receptor site dramatically amplifying the radiation dose delivered to the target. The major challenge with α-generator radiotherapies is that traditional chelating moieties are unable to sequester the radioactive daughters in the bioconjugate which is critical to minimize toxicity to healthy, non-target tissue. The recoil energy of the (225Ac daughters following α decay will sever any metal-ligand bond used to form the bioconjugate. This work demonstrates that an engineered multilayered nanoparticle-antibody conjugate can deliver multiple α radiations and contain the decay daughters of (225Ac while targeting biologically relevant receptors in a female BALB/c mouse model. These multi-shell nanoparticles combine the radiation resistance of lanthanide phosphate to contain (225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established gold chemistry for attachment of targeting moieties.

  10. Synthesis and characterization of thiolated pectin stabilized gold coated magnetic nanoparticles

    International Nuclear Information System (INIS)

    Arora, Varun; Sood, Ankur; Shah, Jyoti; Kotnala, R.K.; Jain, Tapan K.

    2016-01-01

    Core–shell nanoparticles, magnetic core and gold shell, were synthesized by reduction of gold chloride on the surface of magnetic nanoparticles; using tyrosine as a reducing agent. The formation of gold shell on magnetic nanoparticles was confirmed by X-ray diffraction (XRD) and UV-Visible spectroscopy. The core–shell nanoparticles (CSn) were conjugated with thiolated pectin to form a stable aqueous dispersion. The hydrodynamic size of thiolated pectin stabilized core–shell nanoparticles (TP-CSn) measured by Dynamic light scattering (DLS) was 160.5 nm with a poly dispersity index (PDI) of 0.302, whereas the mean particle size of TP-CSn calculated by high resolution transmission electron microscopy (HRTEM) was 10.8 ± 2.7 nm. The value of zeta potential for TP-CSn was −13.6 mV. There was a decrease in the value of saturation magnetization upon formation of the gold shell on magnetic nanoparticles. The amount of thiolated pectin bound to the surface of core–shell nanoparticles, calculated using Thermogravimetric analysis (TGA), was 6% of sample weight. - Highlights: • Use of side group of tyrosine (phenol) as a pH dependent reducing agent to synthesize gold coated magnetic nanoparticles. • Successful coating of gold shell on magnetic nanoparticles core. • Synthesis of thiolated pectin and stabilization of aqueous dispersion of core–shell nanoparticles with thiolated pectin. • The superparamagnetic behaviour of magnetic nanoparticles is retained after shell formation.

  11. Electrochemical analysis of gold-coated magnetic nanoparticles for detecting immunological interaction

    International Nuclear Information System (INIS)

    Pham, Thao Thi-Hien; Sim, Sang Jun

    2010-01-01

    An electrochemical impedance immunosensor was developed for detecting the immunological interaction between human immunoglobulin (IgG) and protein A from Staphylococcus aureus based on the immobilization of human IgG on the surface of modified gold-coated magnetic nanoparticles. The nanoparticles with an Au shell and Fe oxide cores were functionalized by a self-assembled monolayer of 11-mercaptoundecanoic acid. The electrochemical analysis was conducted on the modified magnetic carbon paste electrodes with the nanoparticles. The magnetic nanoparticles were attached to the surface of the magnetic carbon paste electrodes via magnetic force. The cyclic voltammetry technique and electrochemical impedance spectroscopy measurements of the magnetic carbon paste electrodes coated with magnetic nanoparticles-human IgG complex showed changes in its alternating current (AC) response both after the modification of the surface of the electrode and the addition of protein A. The immunological interaction between human IgG on the surface of the modified magnetic carbon paste electrodes and protein A in the solution could be successfully monitored.

  12. Synthesis and magnetic property of T4 virus-supported gold-coated iron ternary nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Xu Ziming; Sun Hongjing; Gao Faming, E-mail: fmgao@ysu.edu.cn; Hou Li; Li Na [Yanshan University, Key Laboratory of Applied Chemistry (China)

    2012-12-15

    Herein, we present a novel method based on the use of the symmetrical T4 bacteriophage capsid as a scaffold for preparing the gold-coated iron ternary core/shell nanostructure. Results showed that the thick gold shell was obtained to effectively protect Fe core from oxidation. Magnetic measurements showed that the nanocomposites were superparamagnetic at room temperature with a blocking temperature of about 35 K. At 3 K, its coercivity of 1142.86 Oe was larger than the existing experimental values. The magnetic property of Au/T4 was also tested, demonstrating the source of the magnetic sample arising from the Fe core only. The absorption spectrum of the Fe-Au/T4 complex was measured and compared with gold/virus. Different thickness gold shells were controlled in the synthesis by tuning the Au salt addition. On the basis of results and discussion, we further speculated the general growing mechanism of the template-supported Fe-Au process.

  13. Gold-Coated Iron Composite Nanospheres Targeted the Detection of Escherichia coli

    Directory of Open Access Journals (Sweden)

    İlker Dinçer

    2013-03-01

    Full Text Available We report the preparation and characterization of spherical core-shell structured Fe3O4–Au magnetic nanoparticles, modified with two component self-assembled monolayers (SAMs consisting of 3–mercaptophenylboronic acid (3–MBA and 1–decanethiol (1–DT. The rapid and room temperature synthesis of magnetic nanoparticles was achieved using the hydroxylamine reduction of HAuCl4 on the surface of ethylenediaminetetraacetic acid (EDTA-immobilized iron (magnetite Fe3O4 nanoparticles in the presence of an aqueous solution of hexadecyltrimetylammonium bromide (CTAB as a dispersant. The reduction of gold on the surface of Fe3O4 nanoparticles exhibits a uniform, highly stable, and narrow particle size distribution of Fe3O4–Au nanoparticles with an average diameter of 9 ± 2 nm. The saturation magnetization value for the resulting nanoparticles was found to be 15 emu/g at 298 K. Subsequent surface modification with SAMs against glucoside moieties on the surface of bacteria provided effective magnetic separation. Comparison of the bacteria capturing efficiency, by means of different molecular recognition agents 3–MBA, 1–DT and the mixed monolayer of 3–MBA and 1–DT was presented. The best capturing efficiency of E. coli was achieved with the mixed monolayer of 3–MBA and 1–DT-modified nanoparticles. Molecular specificity and selectivity were also demonstrated by comparing the surface-enhanced Raman scattering (SERS spectrum of E. coli-nanoparticle conjugates with bacterial growth media.

  14. Gold-coated magnetic nanoparticle as a nanotheranostic agent for magnetic resonance imaging and photothermal therapy of cancer.

    Science.gov (United States)

    Eyvazzadeh, Nazila; Shakeri-Zadeh, Ali; Fekrazad, Reza; Amini, Elahe; Ghaznavi, Habib; Kamran Kamrava, S

    2017-09-01

    Because of their great scientific and technological potentials, iron oxide nanoparticles (IONPs) have been the focus of extensive investigations in biomedicine over the past decade. Additionally, the surface plasmon resonance effect of gold nanoparticles (AuNPs) makes them a good candidate for photothermal therapy applications. The unique properties of both IONPs (magnetic) and AuNPs (surface plasmon resonance) may lead to the development of a multi-modal nanoplatform to be used as a magnetic resonance imaging (MRI) contrast agent and as a nanoheater for photothermal therapy. Herein, core-shell gold-coated IONPs (Au@IONPs) were synthesized and investigated as an MRI contrast agent and as a light-responsive agent for cancer photothermal therapy.The synthesized Au@IONPs were characterized by UV-visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential analysis. The transverse relaxivity (r 2 ) of the Au@IONPs was measured using a 3-T clinical MRI scanner. Through a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of the Au@IONs was examined on a KB cell line, derived from the epidermal carcinoma of a human mouth. Moreover, the photothermal effects of Au@IONPs in the presence of a laser beam (λ = 808 nm; 6.3 W/cm 2 ; 5 min) were studied.The results show that the Au@IONPs are spherical with a hydrodynamic size of 33 nm. A transverse relaxivity of 95 mM -1  S -1 was measured for the synthesized Au@IONPs. It is evident from the MTT results that no significant cytotoxicity in KB cells occurs with Au@IONPs. Additionally, no significant cell damage induced by the laser is observed. Following the photothermal treatment using Au@IONPs, approximately 70% cell death is achieved. It is found that cell lethality depended strongly on incubation period and the Au@IONP concentration.The data highlight the potential of Au@IONPs as a dual-function MRI contrast agent and

  15. Enzyme-functionalized gold-coated magnetite nanoparticles as novel hybrid nanomaterials: synthesis, purification and control of enzyme function by low-frequency magnetic field.

    Science.gov (United States)

    Majouga, Alexander; Sokolsky-Papkov, Marina; Kuznetsov, Artem; Lebedev, Dmitry; Efremova, Maria; Beloglazkina, Elena; Rudakovskaya, Polina; Veselov, Maxim; Zyk, Nikolay; Golovin, Yuri; Klyachko, Natalia; Kabanov, Alexander

    2015-01-01

    The possibility of remotely inducing a defined effect on NPs by means of electromagnetic radiation appears attractive. From a practical point of view, this effect opens horizons for remote control of drug release systems, as well as modulation of biochemical functions in cells. Gold-coated magnetite nanoparticles are perfect candidates for such application. Herein, we have successfully synthesized core-shell NPs having magnetite cores and gold shells modified with various sulphur containing ligands and developed a new, simple and robust procedure for the purification of the resulting nanoparticles. The carboxylic groups displayed at the surface of the NPs were utilized for NP conjugation with a model enzyme (ChT). In the present study, we report the effect of the low-frequency AC magnetic field on the catalytic activity of the immobilized ChT. We show that the enzyme activity decreases upon exposure of the NPs to the field. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Preparation and characterisation of platinum- and gold-coated copper, iron, cobalt and nickel deposits on glassy carbon substrates

    International Nuclear Information System (INIS)

    Papadimitriou, S.; Tegou, A.; Pavlidou, E.; Armyanov, S.; Valova, E.; Kokkinidis, G.; Sotiropoulos, S.

    2008-01-01

    Pt- and Au-coated Cu, Fe, Co and Ni deposits have been formed on glassy carbon (GC) substrates by electrodeposition of controlled amounts of the core metal onto the substrate and its subsequent partial replacement by Pt or Au upon immersion into a chloroplatinic or chlorolauric solution. This process resulted in a thin Pt or Au shell over the bimetallic particle as electrochemical evidence suggests, while indicative sputter-etch Auger Electron Spectroscopy points to the coexistence of the two metals in the particle core. SEM/EDS characterisation of the deposits revealed the existence of Pt(M) and Au(M) extensively agglomerated nanoparticles (M: Cu, Fe, Co, Ni). The surface electrochemistry of the deposits (hydrogen adsorption/desorption on Pt and oxide formation/stripping on Au) proved the complete coverage of the bimetallic particles by Pt or Au and allowed an estimate of their electroactive surface area. The study of hydrogen evolution at these deposits points to a modification of the electronic properties of the Pt and Au surface layers by the core metal (due to strain effects and/or ligand-electronic interactions) and further confirmed that these layers form a very thin outer shell

  17. Hybrid gold-iron oxide nanoparticles as a multifunctional platform for biomedical application

    Directory of Open Access Journals (Sweden)

    Hoskins Clare

    2012-06-01

    Full Text Available Abstract Background Iron oxide nanoparticles (IONPs have increasing applications in biomedicine, however fears over long term stability of polymer coated particles have arisen. Gold coating IONPs results in particles of increased stability and robustness. The unique properties of both the iron oxide (magnetic and gold (surface plasmon resonance result in a multimodal platform for use as MRI contrast agents and as a nano-heater. Results Here we synthesize IONPs of core diameter 30 nm and gold coat using the seeding method with a poly(ethylenimine intermediate layer. The final particles were coated in poly(ethylene glycol to ensure biocompatibility and increase retention times in vivo. The particle coating was monitored using FTIR, PCS, UV–vis absorption, TEM, and EDX. The particles appeared to have little cytotoxic effect when incubated with A375M cells. The resultant hybrid nanoparticles (HNPs possessed a maximal absorbance at 600 nm. After laser irradiation in agar phantom a ΔT of 32°C was achieved after only 90 s exposure (50 μgmL-1. The HNPs appeared to decrease T2 values in line with previously clinically used MRI contrast agent Feridex®. Conclusions The data highlights the potential of these HNPs as dual function MRI contrast agents and nano-heaters for therapies such as cellular hyperthermia or thermo-responsive drug delivery.

  18. Elimination of Tumor Cells Using Folate Receptor Targeting by Antibody-Conjugated, Gold-Coated Magnetite Nanoparticles in a Murine Breast Cancer Model

    Directory of Open Access Journals (Sweden)

    Evan S. Krystofiak

    2012-01-01

    Full Text Available Background. The chemotherapeutic treatment of cancer suffers from poor specificity for targeting the tumor cells and often results in adverse effects such as systemic toxicity, damage to nontarget tissues, and development of drug-resistant tumors in patients. Increasingly, drug nanocarriers have been explored as a way of lessening or overcoming these problems. In this study, antibody-conjugated Au-coated magnetite nanoparticles, in conjunction with inductive heating produced by exposure to an oscillating magnetic field (OMF, were evaluated for their effects on the viability of tumor cells in a murine model of breast cancer. Treatment effects were evaluated by light microscopy and SEM. Results. 4T1 mammary epithelial carcinoma cells overexpressing the folate receptor were targeted with an anti-folate receptor primary antibody, followed by labeling with secondary antibody-conjugated Au-coated magnetite nanoparticles. In the absence of OMF exposure, nanoparticle labeling had no effect on 4T1 cell viability. However, following OMF treatment, many of the labeled 4T1 cells showed extensive membrane damage by SEM analysis, and dramatically reduced viability as assessed using a live/dead staining assay. Conclusions. These results demonstrate that Au-coated magnetite targeted to tumor cells through binding to an overexpressed surface receptor, in the presence of an OMF, can lead to tumor cell death.

  19. Electrochemical genoassays on gold-coated magnetic nanoparticles to quantify genetically modified organisms (GMOs) in food and feed as GMO percentage.

    Science.gov (United States)

    Plácido, Alexandra; Pereira, Clara; Guedes, Alexandra; Barroso, M Fátima; Miranda-Castro, Rebeca; de-Los-Santos-Álvarez, Noemí; Delerue-Matos, Cristina

    2018-03-21

    The integration of nanomaterials in the field of (bio)sensors has allowed developing strategies with improved analytical performance. In this work, ultrasmall core-shell Fe 3 O 4 @Au magnetic nanoparticles (MNPs) were used as the platform for the immobilization of event-specific Roundup Ready (RR) soybean and taxon-specific DNA sequences. Firstly, monodisperse Fe 3 O 4 MNPs were synthesized by thermal decomposition and subsequently coated with a gold shell through reduction of Au(III) precursor on the surface of the MNPs in the presence of an organic capping agent. This nanosupport exhibited high colloidal stability, average particle size of 10.2 ± 1.3 nm, and spherical shape. The covalent immobilization of ssDNA probe onto the Au shell of the Fe 3 O 4 @Au MNPs was achieved through a self-assembled monolayer (SAM) created from mixtures of alkane thiols (6-mercapto-1-hexanol and mercaptohexanoic acid). The influence of the thiols ratio on the electrochemical performance of the resulting electrochemical genoassays was studied, and remarkably, the best analytical performance was achieved for a pure mercaptohexanoic acid SAM. Two quantification assays were designed; one targeting an RR sequence and a second targeting a reference soybean gene, both with a sandwich format for hybridization, signaling probes labelled with fluorescein isothiocyanate (FITC), enzymatic amplification and chronoamperometric detection at screen-printed carbon electrodes (SPCE). The magnetogenoassays exhibited linear ranges from 0.1 to 10.0 nM and from 0.1 to 5.0 nM with similar detection limits of 0.02 nM and 0.05 nM for the event-specific (RR) and the taxon-specific (lectin) targets, respectively. The usefulness of the approach was demonstrated by its application to detect genetically modified organisms (GMOs) in feed and food. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Thermodynamics and Charging of Interstellar Iron Nanoparticles

    OpenAIRE

    Hensley, Brandon S.; Draine, B. T.

    2016-01-01

    Interstellar iron in the form of metallic iron nanoparticles may constitute a component of the interstellar dust. We compute the stability of iron nanoparticles to sublimation in the interstellar radiation field, finding that iron clusters can persist down to a radius of $\\simeq 4.5\\,$\\AA, and perhaps smaller. We employ laboratory data on small iron clusters to compute the photoelectric yields as a function of grain size and the resulting grain charge distribution in various interstellar envi...

  1. Tannin biosynthesis of iron oxide nanoparticles

    Science.gov (United States)

    Herrera-Becerra, R.; Rius, J. L.; Zorrilla, C.

    2010-08-01

    In this work, iron oxide nanoparticles synthesized with gallic acid and tannic acid are characterized using High-Resolution Transmission Electron Microscopy (HRTEM). Its size, form, and structure are compared with nanoparticles obtained previously using alfalfa biomass in order to find a simpler, consistent, and environmentally friendly method in the production of iron oxide nanoparticles.

  2. Determination of gold coating thickness measurement by using EDXRF

    International Nuclear Information System (INIS)

    Meor Yusoff Meor Sulaian; Masliana Muslimin; Fadlullah Jili Fursani

    2005-01-01

    The paper relates a study on the development of an analysis procedure for measuring the gold coating thickness using EDXRF technique. Gold coating thickness was measured by relating the counts under the Au L? peak its thickness value. In order to get a reasonably accurate result, a calibration graph was plotted using five gold-coated reference standards of different thickness. The calibration graph shows a straight line for thin coating measurement until 0.9 μm. Beyond this the relationship was not linear and this may be resulted from the self-absorption effect. Quantitative analysis was also performed on two different samples of gold coated jewelry and a phone connector. Result from the phone connector analysis seems to agree with the manufacturer gold coating value. From the analysis of gold-coated jewelry it had been able to differentiate the two articles as gold wash and gold electroplated. (Author)

  3. Magnetic properties of iron nanoparticle

    International Nuclear Information System (INIS)

    Carvell, J.; Ayieta, E.; Gavrin, A.; Cheng, Ruihua; Shah, V. R.; Sokol, P.

    2010-01-01

    Magnetic properties of Fe nanoparticles with different sizes synthesized by a physical deposition technique have been investigated experimentally. We have used a high pressure sputtering technique to deposit iron nanoparticles on a silicon substrate. The nanoparticles are then analyzed using atomic force microscopy (AFM), transmission electron microscopy (TEM), and superconducting quantum interference device techniques. TEM and AFM data show that the particle size could be tuned by adjusting the deposition conditions. The magnetic properties have been investigated from temperature dependent magnetization M(T) and field dependent magnetization M(H) measurements. The results show that two phases including both ferromagnetic and superparamagnetic particles are present in our system. From these data we extracted the superparamagnetic critical size to be 9 nm for our samples. Ferromagnetic particles are single magnetic domain particles and the magnetic properties can be explained by the Stoner and Wohlfarth model. For the superparamagnetic phase, the effective anisotropy constant, K eff , decreases as the particle size increases.

  4. ATMP-stabilized iron nanoparticles: chelator-controlled nanoparticle synthesis

    Science.gov (United States)

    Greenlee, Lauren F.; Rentz, Nikki S.

    2014-11-01

    In this study, we characterize iron nanoparticles synthesized in water in the presence of a phosphonate chelator, amino tris(methylene phosphonic acid) (ATMP) for a range of molar ratios of ATMP to iron. An increase in the molar ratio from 0.05 to 0.8 decreases nanoparticle size from approximately 150 nm to less than 10 nm. Zeta potential measurements were used to evaluate colloidal stability. Zeta potential values varied as a function of pH, and zeta potential values decreased with increasing pH. At lower molar ratios of ATMP to iron, the zeta potential varied between 15 and -40 mV, passing through an isoelectric point at pH 7.5. At higher ratios, the zeta potential was negative across the measured pH range of 2-12 and varied from -2 to -55 mV. Diffraction analysis indicates that ATMP-stabilized iron nanoparticles may have a nano-crystalline structure, potentially with regions of amorphous iron. Characterization results of ATMP-stabilized iron nanoparticles are compared to results obtained for carboxymethyl cellulose (CMC)-stabilized iron nanoparticles. CMC stabilization caused similar peak broadening in diffraction spectra as for ATMP, suggesting similar nano-crystalline/amorphous structure; however, an increase in the molar ratio of CMC to iron did not cause the same reduction in nanoparticle size as was observed for ATMP-stabilized iron nanoparticles.

  5. Nanotoxicity of gold and iron nanoparticles.

    Science.gov (United States)

    Maiti, Souvik

    2011-02-01

    The extensive use of potentially hazardous nanoparticles in industrial applications suggest that their biological effects need to be evaluated following clinical testing practices as applicable for any new pharmaceutical. It was rationalized that a non hypothesis-driven approach is best suited for discovering the biological effects of nanoparticles. Gold nanoparticles (approximately 18 nm), showed no drastic effect on gene expression in cells but iron nanoparticles showed perturbations in the expression of a set of functional genes.

  6. Core-shell iron-iron oxide nanoparticles

    DEFF Research Database (Denmark)

    Kuhn, Luise Theil; Bojesen, A.; Timmermann, L.

    2004-01-01

    We present studies of the magnetic properties of core-shell iron-iron oxide nanoparticles. By combining Mossbauer and X-ray absorption spectroscopy we have been able to measure the change from a Fe3O4-like to a gamma-Fe2O3-like composition from the interface to the surface. Furthermore, we have o...

  7. Phytosynthesized iron nanoparticles: effects on fermentative ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Iron nanoparticles; green synthesis; Syzygium cumini; dark fermentation; biohydrogen production; Enterobacter cloacae. ... Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Tezpur 784 028, Assam, India; Department of Physics, Tezpur University, Napaam, Tezpur 784 028, ...

  8. The synthesis and characterization of iron nanoparticles

    Science.gov (United States)

    Bennett, Tyler

    Nanoparticle synthesis has garnered attention for technological applications for catalysts, industrial processing, and medical applications. The size ranges for these is in the particles nanostructural domain. Pure iron nanoparticles have been of particular interest for their reactivity and relative biological inertness. Applications include cancer treatment and carrying medicine to a relevant site. Unfortunately, because of their reactivity, pure iron nanoparticles have been difficult to study. This is because of their accelerated tendency to form oxides in air, due to the increased surface area to volume ratio. Using synthesis processes with polyphenols or long chain amines, air stable iron nanoparticles have been produced with a diameter size range of ~ 2 to about ~10 nm, but apparently have transformed due to internal pressure and crystallographic defects to the FCC phase. The FCC crystals have been seen to form icosahedral and decahedral shapes. This size is within the range for use as a catalyst for the growth of both carbon nanotubes and boron nitride nanotubes as well for biomedical applications. The advantages of these kinds of catalysts are that nanotube growth can be for the first time separated from the catalyst formation. Additionally, the catalyst size can be preselected for a certain size nanotube to grow. In summary: (1) we found the size distributions of nanoparticles for various synthesis processes, (2) we discovered the right size range for growth of nanotubes from the iron nanoparticles, (3) the nanoparticles are under a very high internal pressure, (4) the nanoparticles are in the FCC phase, (5) they appear to be in icosahedral and decahedral structures, (6) they undergo room temperature twinning, (7) the FCC crystals are distorted due to carbon in octahedral sites, (8) the iron nanoparticles are stable in air, (9) adding small amounts of copper make the iron nanoparticles smaller.

  9. Zero-valent iron nanoparticles preparation

    International Nuclear Information System (INIS)

    Oropeza, S.; Corea, M.; Gómez-Yáñez, C.; Cruz-Rivera, J.J.; Navarro-Clemente, M.E.

    2012-01-01

    Graphical abstract: Zero-valent iron nanoparticles were synthesized by hydrogenating [Fe[N(Si(CH 3 ) 3 ) 2 ] 2 ] at room temperature and a pressure of 3 atm. The synthesized nanoparticles were spherical and had diameters less than 5 nm. Highlights: ► Zero-valent iron nanoparticles were synthesized by hydrogenating [Fe[N(Si(CH 3 ) 3 ) 2 ] 2 ]. ► The conditions of reaction were at room temperature and a pressure of 3 atm. ► The synthesized nanoparticles were spherical and had diameters less than 5 nm. -- Abstract: Zero-valent iron nanoparticles were synthesized by hydrogenating [Fe[N(Si(CH 3 ) 3 ) 2 ] 2 ] at room temperature and a pressure of 3 atm. To monitor the reaction, a stainless steel pressure reactor lined with PTFE and mechanically stirred was designed. This design allowed the extraction of samples at different times, minimizing the perturbation in the system. In this way, the shape and the diameter of the nanoparticles produced during the reaction were also monitored. The results showed the production of zero-valent iron nanoparticles that were approximately 5 nm in diameter arranged in agglomerates. The agglomerates grew to 900 nm when the reaction time increased up to 12 h; however, the diameter of the individual nanoparticles remained almost the same. During the reaction, some byproducts constituted by amino species acted as surfactants; therefore, no other surfactants were necessary.

  10. Phytosynthesized iron nanoparticles: effects on fermentative ...

    Indian Academy of Sciences (India)

    In recent years the application of metal nanoparticles is gaining attention in various fields. The present study focuses on the additive effect of `green' synthesized iron nanoparticles (FeNPs) on dark fermentative hydrogen (H2) production by a mesophilic soil bacterium Enterobacter cloacae. The FeNPs were synthesized by ...

  11. Mixed iron-manganese oxide nanoparticles

    NARCIS (Netherlands)

    Lai, Jriuan; Shafi, Kurikka V.P.M.; Ulman, Abraham; Loos, Katja; Yang, Nan-Loh; Cui, Min-Hui; Vogt, Thomas; Estournès, Claude; Locke, Dave C.

    2004-01-01

    Designing nanoparticles for practical applications requires knowledge and control of how their desired properties relate to their composition and structure. Here, we present a detailed systematic study of mixed iron-manganese oxide nanoparticles, showing that ultrasonication provides the high-energy

  12. Characterization of tetraethylene glycol passivated iron nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, Eloiza da Silva; Viali, Wesley Renato [Laboratório de Materiais Magnéticos e Coloides, Departamento de Físico-química, Instituto de Química, Universidade Estadual Paulista, Araraquara, SP 14801-970 (Brazil); Silva, Sebastião William da; Coaquira, José Antonio Huamaní; Garg, Vijayendra Kumar; Oliveira, Aderbal Carlos de [Instituto de Física, Núcleo de Física Aplicada, Universidade de Brasília, Brasília, DF 70910-900 (Brazil); Morais, Paulo César [Instituto de Física, Núcleo de Física Aplicada, Universidade de Brasília, Brasília, DF 70910-900 (Brazil); School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Jafelicci Júnior, Miguel, E-mail: jafeli@iq.unesp.br [Laboratório de Materiais Magnéticos e Coloides, Departamento de Físico-química, Instituto de Química, Universidade Estadual Paulista, Araraquara, SP 14801-970 (Brazil)

    2014-10-01

    Graphical abstract: - Highlights: • Metallic iron nanoparticles were passivated in tetraethylene glycol media. • Passivated nanoparticles presented pomegranate-like core@shell structure. • Passivation of metallic iron correlates with the tetraethylene glycol degradation. • Boron enriched metallic iron phase was more susceptible to oxidation. • The iron oxide shell was identified as Fe{sub 3}O{sub 4} with a mass fraction of 43:53 related to αFe. - Abstract: The present study describes the synthesis and characterization of iron@iron oxide nanoparticles produced by passivation of metallic iron in tetraethylene glycol media. Structural and chemical characterizations were performed using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Mössbauer spectroscopy. Pomegranate-like core@shell nanoparticulate material in the size range of 90–120 nm was obtained. According to quantitative phase analysis using Rietveld structure refinement the synthesized iron oxide was identified as magnetite (Fe{sub 3}O{sub 4}) whereas the iron to magnetite mass fractions was found to be 47:53. These findings are in good agreement with the data obtained from Mössbauer and thermal gravimetric analysis (TGA). The XPS data revealed the presence of a surface organic layer with higher hydrocarbon content, possibly due to the tetraethylene glycol thermal degradation correlated with iron oxidation. The room-temperature (300 K) saturation magnetization measured for the as-synthesized iron and for the iron–iron oxide were 145 emu g{sup −1} and 131 emu g{sup −1}, respectively. The measured saturation magnetizations are in good agreement with data obtained from TEM, XRD and Mössbauer spectroscopy.

  13. Effects of gold coating on experimental implant fixation

    DEFF Research Database (Denmark)

    Zainali, Kasra; Danscher, Gorm; Jakobsen, Thomas

    2009-01-01

    -kinase activation. The present study investigated whether gilding implant Surfaces augmented early implant osseointegration and implant fixation by its modulatory effect on the local inflammatory response. Ion release was traced by autometallographic silver enhancement. Gold-coated cylindrical porous coated Ti6Al4V...... implants Were inserted press-fit in the proximal part of tibiae in nine canines and control implants without gold inserted contralateral. Observation time was 4 weeks. Biomechanical push-out tests showed that implant,,, with gold coating had decrease in mechanical strength and stiffness....... Histomorphometrical analyses showed gold-coated implants had a decrease in overall total bone-to-implant contact of 35%. Autometallographic analysis revealed few cells loaded with gold close to the gilded implant surface. The findings demonstrate that gilding of implants negatively, affects mechanical strength...

  14. Process to Produce Iron Nanoparticle Lunar Dust Simulant Composite

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2010-01-01

    A document discusses a method for producing nanophase iron lunar dust composite simulant by heating a mixture of carbon black and current lunar simulant types (mixed oxide including iron oxide) at a high temperature to reduce ionic iron into elemental iron. The product is a chemically modified lunar simulant that can be attracted by a magnet, and has a surface layer with an iron concentration that is increased during the reaction. The iron was found to be -iron and Fe3O4 nanoparticles. The simulant produced with this method contains iron nanoparticles not available previously, and they are stable in ambient air. These nanoparticles can be mass-produced simply.

  15. D, L-Sulforaphane Loaded Fe3O4@ Gold Core Shell Nanoparticles: A Potential Sulforaphane Delivery System.

    Science.gov (United States)

    Kheiri Manjili, Hamidreza; Ma'mani, Leila; Tavaddod, Sharareh; Mashhadikhan, Maedeh; Shafiee, Abbas; Naderi-Manesh, Hossein

    2016-01-01

    A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line) as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL), and the pro-apoptotic genes (bax and bak) were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.

  16. D, L-Sulforaphane Loaded Fe3O4@ Gold Core Shell Nanoparticles: A Potential Sulforaphane Delivery System.

    Directory of Open Access Journals (Sweden)

    Hamidreza Kheiri Manjili

    Full Text Available A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL, and the pro-apoptotic genes (bax and bak were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.

  17. Acid monolayer functionalized iron oxide nanoparticle catalysts

    Science.gov (United States)

    Ikenberry, Myles

    Superparamagnetic iron oxide nanoparticle functionalization is an area of intensely active research, with applications across disciplines such as biomedical science and heterogeneous catalysis. This work demonstrates the functionalization of iron oxide nanoparticles with a quasi-monolayer of 11-sulfoundecanoic acid, 10-phosphono-1-decanesulfonic acid, and 11-aminoundecanoic acid. The carboxylic and phosphonic moieties form bonds to the iron oxide particle core, while the sulfonic acid groups face outward where they are available for catalysis. The particles were characterized by thermogravimetric analysis (TGA), transmission electron microscopy (TEM), potentiometric titration, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray photoelectron spectrometry (XPS), and dynamic light scattering (DLS). The sulfonic acid functionalized particles were used to catalyze the hydrolysis of sucrose at 80° and starch at 130°, showing a higher activity per acid site than the traditional solid acid catalyst Amberlyst-15, and comparing well against results reported in the literature for sulfonic acid functionalized mesoporous silicas. In sucrose catalysis reactions, the phosphonic-sulfonic nanoparticles (PSNPs) were seen to be incompletely recovered by an external magnetic field, while the carboxylic-sulfonic nanoparticles (CSNPs) showed a trend of increasing activity over the first four recycle runs. Between the two sulfonic ligands, the phosphonates produced a more tightly packed monolayer, which corresponded to a higher sulfonic acid loading, lower agglomeration, lower recoverability through application of an external magnetic field, and higher activity per acid site for the hydrolysis of starch. Functionalizations with 11-aminoundecanoic acid resulted in some amine groups binding to the surfaces of iron oxide nanoparticles. This amine binding is commonly ignored in iron oxide

  18. Magnetic properties of iron nanoparticles prepared by exploding wire technique

    OpenAIRE

    Alqudami, Abdullah; Annapoorni, S.; Lamba, Subhalakshmi; Kothari, P C; Kotnala, R K

    2006-01-01

    Nanoparticles of iron were prepared in distilled water using very thin iron wires and sheets, by the electro-exploding wire technique. Transmission electron microscopy reveals the size of the nanoparticles to be in the range 10 to 50 nm. However, particles of different sizes can be segregated by using ultrahigh centrifuge. X-ray diffraction studies confirm the presence of the cubic phase of iron. These iron nanoparticles were found to exhibit fluorescence in the visible region in contrast to ...

  19. Low temperature hydrogenation of iron nanoparticles on graphene

    OpenAIRE

    Takahashi, Keisuke; Wang, Yongming; Chiba, Shotaro; Nakagawa, Yuki; Isobe, Shigehito; Ohnuki, Somei

    2014-01-01

    Hydrogenation of iron nanoparticles was performed both computationally and experimentally where previously chemically-bonded iron hydride is considered to be unachievable under ordinary conditions. Density functional theory (DFT) calculations predict that hydrogenated iron nanoparticles are stabilized on a single-layer graphene/Cu substrate. Experimentally, iron nanoparticles were deposited onto a graphene/Cu substrate by vacuum deposition. Hydrogenation was done at 1atm of hydrogen gas and u...

  20. Toxicity of iron oxide nanoparticles against osteoblasts

    Energy Technology Data Exchange (ETDEWEB)

    Shi Sifeng [Shanghai Jiao Tong University, Department of Orthopaedic Surgery, Shanghai Sixth People' s Hospital (China); Jia Jingfu [Shanghai Jiao Tong University, School of Chemistry and Chemical Technology (China); Guo Xiaokui [Shanghai Jiao Tong University School of Medicine, Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences (China); Zhao Yaping [Shanghai Jiao Tong University, School of Chemistry and Chemical Technology (China); Liu Boyu [Shanghai Jiao Tong University School of Medicine, Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences (China); Chen Desheng; Guo Yongyuan; Zhang Xianlong, E-mail: zhangxianlong20101@163.com [Shanghai Jiao Tong University, Department of Orthopaedic Surgery, Shanghai Sixth People' s Hospital (China)

    2012-09-15

    Magnetic nanoparticles have been widely used for tissue repair, magnetic resonance imaging, immunoassays and drug delivery. They are very promising in orthopaedic applications and several magnetic nanoparticles have been exploited for the treatment of orthopaedic disease. Here, we conducted an in vitro study to examine the interaction of magnetic iron oxide nanoparticles with human osteoblasts to evaluate the dose-related toxicity of the nanoparticles on osteoblasts. A transmission electron microscope was used to visualise the internalised magnetic nanoparticles in osteoblasts. The CCK-8 results revealed increased cell viability (107.5 % vitality compared with the control group) when co-cultured at a low concentration (20 {mu}g/mL) and decreased cell viability (59.5 % vitality in a concentration of 300 {mu}g/mL and 25.9 % in 500 {mu}g/mL) when co-cultured in high concentrations. The flow cytometric detection revealed similar results with 5.48 % of apoptosis in a concentration of 20 {mu}g/mL, 23.40 % of apoptosis in a concentration of 300 {mu}g/mL and 28.49 % in a concentration of 500 {mu}g/mL. The disrupted cytoskeleton of osteoblasts was also revealed using a laser scanning confocal microscope. We concluded that use of a low concentration of magnetic iron oxide nanoparticles is important to avoid damage to osteoblasts.

  1. Toxicity of iron oxide nanoparticles against osteoblasts

    International Nuclear Information System (INIS)

    Shi Sifeng; Jia Jingfu; Guo Xiaokui; Zhao Yaping; Liu Boyu; Chen Desheng; Guo Yongyuan; Zhang Xianlong

    2012-01-01

    Magnetic nanoparticles have been widely used for tissue repair, magnetic resonance imaging, immunoassays and drug delivery. They are very promising in orthopaedic applications and several magnetic nanoparticles have been exploited for the treatment of orthopaedic disease. Here, we conducted an in vitro study to examine the interaction of magnetic iron oxide nanoparticles with human osteoblasts to evaluate the dose-related toxicity of the nanoparticles on osteoblasts. A transmission electron microscope was used to visualise the internalised magnetic nanoparticles in osteoblasts. The CCK-8 results revealed increased cell viability (107.5 % vitality compared with the control group) when co-cultured at a low concentration (20 μg/mL) and decreased cell viability (59.5 % vitality in a concentration of 300 μg/mL and 25.9 % in 500 μg/mL) when co-cultured in high concentrations. The flow cytometric detection revealed similar results with 5.48 % of apoptosis in a concentration of 20 μg/mL, 23.40 % of apoptosis in a concentration of 300 μg/mL and 28.49 % in a concentration of 500 μg/mL. The disrupted cytoskeleton of osteoblasts was also revealed using a laser scanning confocal microscope. We concluded that use of a low concentration of magnetic iron oxide nanoparticles is important to avoid damage to osteoblasts.

  2. CO2 hydrogenation to hydrocarbons over iron nanoparticles ...

    Indian Academy of Sciences (India)

    active nanoparticles.17 Oxygen functionalization of the exposed graphitic CNT surfaces is required to provide strong anchoring sites for the deposited nanoparticles.21. Here, we report CO2 hydrogenation to hydrocar- bons over iron nanoparticles supported on oxygen- functionalized CNTs (OCNTs). The iron catalyst was.

  3. Surface effects in metallic iron nanoparticles

    DEFF Research Database (Denmark)

    Bødker, Franz; Mørup, Steen; Linderoth, Søren

    1994-01-01

    Nanoparticles of metallic iron on carbon supports have been studied in situ by use of Mossbauer spectroscopy. The magnetic anisotropy energy constant increases with decreasing particle size, presumably because of the influence of surface anisotropy. Chemisorption of oxygen results in formation...... of a surface layer with magnetic hyperfine fields similar to those of thicker passivation layers, and with a ferromagnetic coupling to the spins in the core of the particles. In contrast, thicker passivation layers have a noncollinear spin structure....

  4. Synthesis and magnetic characterizations of uniform iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Jiang, FuYi; Li, XiaoYi; Zhu, Yuan; Tang, ZiKang

    2014-01-01

    Uniform iron oxide nanoparticles with a cubic shape were prepared by the decomposition of homemade iron oleate in 1-octadecene with the presence of oleic acid. The particle shape and size uniformity are sensitive to the quantity of oleic acid. XRD, HRTEM and SAED results indicated that the main phase content of as-prepared iron oxide nanoparticles is Fe 3 O 4 with an inverse spinel structure. Magnetic measurements revealed that the as-prepared iron oxide nanoparticles display a ferromagnetic behavior with a blocking temperature of 295 K. At low temperatures the magnetic anisotropy of the aligned nanoparticles caused the appearance of a hysteresis loop.

  5. A Fast and Cost-Effective Detection of Melamine by Surface Enhanced Raman Spectroscopy Using a Novel Hydrogen Bonding-Assisted Supramolecular Matrix and Gold-Coated Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jing Neng

    2017-05-01

    Full Text Available A fast and cost-effective melamine detection approach has been developed based on surface enhanced Raman spectroscopy (SERS using a novel hydrogen bonding-assisted supramolecular matrix. The detection utilizes Fe3O4/Au magnetic nanoparticles coated with 5-aminoorotic acid (AOA as a SERS active substrate (Fe3O4/Au–AOA, and Rhodamine B (RhB conjugated AOA as a Raman reporter (AOA–RhB. Upon mixing the reagents with melamine, a supramolecular complex [Fe3O4/Au–AOA•••melamine•••AOA–RhB] was formed due to the strong multiple hydrogen bonding interactions between AOA and melamine. The complex was separated and concentrated to a pellet by an external magnet and used as a supramolecular matrix for the melamine detection. Laser excitation of the complex pellet produced a strong SERS signal diagnostic for RhB. The logarithmic intensity of the characteristic RhB peaks was found to be proportional to the concentration of melamine with a limit of detection of 2.5 µg/mL and a detection linearity range of 2.5~15.0 µg/mL in milk. As Fe3O4 nanoparticles and AOA are thousands of times less expensive than the monoclonal antibody used in a traditional sandwich immunoassay, the current assay drastically cut down the cost of melamine detection. The current approach affords promise as a biosensor platform that cuts down sample pre-treatment steps and measurement expense.

  6. Biogenic Fabrication of Iron/Iron Oxide Nanoparticles and Their Application

    OpenAIRE

    Siddiqi, Khwaja Salahuddin; ur Rahman, Aziz; Tajuddin,; Husen, Azamal

    2016-01-01

    Enshrined in this review are the biogenic fabrication and applications of coated and uncoated iron and iron oxide nanoparticles. Depending on their magnetic properties, they have been used in the treatment of cancer, drug delivery system, MRI, and catalysis and removal of pesticides from potable water. The polymer-coated iron and iron oxide nanoparticles are made biocompatible, and their slow release makes them more effective and lasting. Their cytotoxicity against microbes under aerobic/anae...

  7. Investigation of carrier oil stabilized iron oxide nanoparticles and its ...

    African Journals Online (AJOL)

    Iron oxide nanoparticles were synthesized by co-precipitation method. The polyunsaturated carrier oil (flaxseed oil) is used as a stabilizing agent for iron oxide nanoparticles. Kirby Bauer method was used to investigate the antibiotic sensitivity of carrier oil stabilized and uncoated SPIONs at 10 and 20 μg/L on Gram-positive ...

  8. Washing effect on superparamagnetic iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Laura-Karina Mireles

    2016-06-01

    Full Text Available Much recent research on nanoparticles has occurred in the biomedical area, particularly in the area of superparamagnetic iron oxide nanoparticles (SPIONs; one such area of research is in their use as magnetically directed prodrugs. It has been reported that nanoscale materials exhibit properties different from those of materials in bulk or on a macro scale [1]. Further, an understanding of the batch-to-batch reproducibility and uniformity of the SPION surface is essential to ensure safe biological applications, as noted in the accompanying article [2], because the surface is the first layer that affects the biological response of the human body. Here, we consider a comparison of the surface chemistries of a batch of SPIONs, before and after the supposedly gentle process of dialysis in water.

  9. Effects of coating spherical iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Milosevic, Irena; Motte, Laurence; Aoun, Bachir; Li, Tao; Ren, Yang; Sun, Chengjun; Saboungi, Marie-Louise

    2017-01-01

    We investigate the effect of several coatings applied in biomedical applications to iron oxide nanoparticles on the size, structure and composition of the particles. The four structural techniques employed - TEM, DLS, VSM, SAXS and EXAFS - show no significant effects of the coatings on the spherical shape of the bare nanoparticles, the average sizes or the local order around the Fe atoms. The NPs coated with hydroxylmethylene bisphosphonate or catechol have a lower proportion of magnetite than the bare and citrated ones, raising the question whether the former are responsible for increasing the valence state of the oxide on the NP surfaces and lowering the overall proportion of magnetite in the particles. VSM measurements show that these two coatings lead to a slightly higher saturation magnetization than the citrate. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazu and Dr. Federica Migliardo.

  10. High temperature oxidation of iron-iron oxide core-shell nanowires composed of iron nanoparticles.

    Science.gov (United States)

    Krajewski, M; Brzozka, K; Lin, W S; Lin, H M; Tokarczyk, M; Borysiuk, J; Kowalski, G; Wasik, D

    2016-02-07

    This work describes an oxidation process of iron-iron oxide core-shell nanowires at temperatures between 100 °C and 800 °C. The studied nanomaterial was synthesized through a simple chemical reduction of iron trichloride in an external magnetic field under a constant flow of argon. The electron microscopy investigations allowed determining that the as-prepared nanowires were composed of self-assembled iron nanoparticles which were covered by a 3 nm thick oxide shell and separated from each other by a thin interface layer. Both these layers exhibited an amorphous or highly-disordered character which was traced by means of transmission electron microscopy and Mössbauer spectroscopy. The thermal oxidation was carried out under a constant flow of argon which contained the traces of oxygen. The first stage of process was related to slow transformations of amorphous Fe and amorphous iron oxides into crystalline phases and disappearance of interfaces between iron nanoparticles forming the studied nanomaterial (range: 25-300 °C). After that, the crystalline iron core and iron oxide shell became oxidized and signals for different compositions of iron oxide sheath were observed (range: 300-800 °C) using X-ray diffraction, Raman spectroscopy and Mössbauer spectroscopy. According to the thermal gravimetric analysis, the nanowires heated up to 800 °C under argon atmosphere gained 37% of mass with respect to their initial weight. The structure of the studied nanomaterial oxidized at 800 °C was mainly composed of α-Fe2O3 (∼ 93%). Moreover, iron nanowires treated above 600 °C lost their wire-like shape due to their shrinkage and collapse caused by the void coalescence.

  11. Ultrafine ferromagnetic iron oxide nanoparticles: Facile synthesis by low temperature decomposition of iron glycerolate

    Energy Technology Data Exchange (ETDEWEB)

    Bartůněk, Vilém, E-mail: vilem.bartunek@vscht.cz [Department of Inorganic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6 (Czech Republic); Průcha, David [Department of Inorganic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6 (Czech Republic); Švecová, Marie [Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology, Technická 5, 166 28 Prague 6 (Czech Republic); Ulbrich, Pavel [Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technická 3, 166 28 Prague 6 (Czech Republic); Huber, Štěpán; Sedmidubský, David; Jankovský, Ondřej [Department of Inorganic Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6 (Czech Republic)

    2016-09-01

    We synthesized dark colored ultrafine – sub 10 nm iron oxide nanoparticles by a facile and low temperature process based on thermal decomposition of an affordable precursor – iron glycerolate. Simultaneous thermal analysis (STA) was used to study the thermal behaviour during the decomposition. The iron glycerolate was thoroughly analysed by various methods. The size of the iron nanoparticles was determined from XRD patterns and by transmission electron microscopy (TEM) and their composition has been confirmed by XPS. Magnetic properties of the nanoparticles were studied by vibrating sample magnetometry. The prepared single phase material exhibiting ferromagnetic properties is usable in a wide range of applications and may be suitable even for large scale industrial applications. - Highlights: • Iron glycerolate prepared and characterised. • Iron oxide nanoparticles prepared by thermal decomposition of iron glycerolate. • STA used to study the decomposition. • Products characterised by XRD, XPS, FT-IR, SEM and TEM. • Magnetic behaviour of monophasic samples determined.

  12. Effect of magnetic iron oxide nanoparticles on pregnancy and ...

    African Journals Online (AJOL)

    Although, some studies revealed the nontoxic effect of iron oxide nanoparticles in adult mice, the present study indicated that, the doses higher than 50 mg/kg of DMSA-coated magnetic nanoparticles can disrupt embryo development. Key words: Magnetic nanoparticles, pregnancy, testicular development, toxicity.

  13. Safety assessment of chronic oral exposure to iron oxide nanoparticles

    Science.gov (United States)

    Chamorro, Susana; Gutiérrez, Lucía; Vaquero, María Pilar; Verdoy, Dolores; Salas, Gorka; Luengo, Yurena; Brenes, Agustín; José Teran, Francisco

    2015-05-01

    Iron oxide nanoparticles with engineered physical and biochemical properties are finding a rapidly increasing number of biomedical applications. However, a wide variety of safety concerns, especially those related to oral exposure, still need to be addressed for iron oxide nanoparticles in order to reach clinical practice. Here, we report on the effects of chronic oral exposure to low doses of γ-Fe2O3 nanoparticles in growing chickens. Animal observation, weight, and diet intake reveal no adverse signs, symptoms, or mortality. No nanoparticle accumulation was observed in liver, spleen, and duodenum, with feces as the main excretion route. Liver iron level and duodenal villi morphology reflect the bioavailability of the iron released from the partial transformation of γ-Fe2O3 nanoparticles in the acid gastric environment. Duodenal gene expression studies related to the absorption of iron from γ-Fe2O3 nanoparticles indicate the enhancement of a ferric over ferrous pathway supporting the role of mucins. Our findings reveal that oral administration of iron oxide nanoparticles is a safe route for drug delivery at low nanoparticle doses.

  14. Safety assessment of chronic oral exposure to iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Chamorro, Susana; Vaquero, María Pilar; Brenes, Agustín; Gutiérrez, Lucía; Salas, Gorka; Luengo, Yurena; Verdoy, Dolores; José Teran, Francisco

    2015-01-01

    Iron oxide nanoparticles with engineered physical and biochemical properties are finding a rapidly increasing number of biomedical applications. However, a wide variety of safety concerns, especially those related to oral exposure, still need to be addressed for iron oxide nanoparticles in order to reach clinical practice. Here, we report on the effects of chronic oral exposure to low doses of γ-Fe 2 O 3 nanoparticles in growing chickens. Animal observation, weight, and diet intake reveal no adverse signs, symptoms, or mortality. No nanoparticle accumulation was observed in liver, spleen, and duodenum, with feces as the main excretion route. Liver iron level and duodenal villi morphology reflect the bioavailability of the iron released from the partial transformation of γ-Fe 2 O 3 nanoparticles in the acid gastric environment. Duodenal gene expression studies related to the absorption of iron from γ-Fe 2 O 3 nanoparticles indicate the enhancement of a ferric over ferrous pathway supporting the role of mucins. Our findings reveal that oral administration of iron oxide nanoparticles is a safe route for drug delivery at low nanoparticle doses. (paper)

  15. Effects of coating spherical iron oxide nanoparticles.

    Science.gov (United States)

    Milosevic, Irena; Motte, Laurence; Aoun, Bachir; Li, Tao; Ren, Yang; Sun, Chengjun; Saboungi, Marie-Louise

    2017-01-01

    We investigate the effect of several coatings applied in biomedical applications to iron oxide nanoparticles on the size, structure and composition of the particles. The four structural techniques employed - TEM, DLS, VSM, SAXS and EXAFS - show no significant effects of the coatings on the spherical shape of the bare nanoparticles, the average sizes or the local order around the Fe atoms. The NPs coated with hydroxylmethylene bisphosphonate or catechol have a lower proportion of magnetite than the bare and citrated ones, raising the question whether the former are responsible for increasing the valence state of the oxide on the NP surfaces and lowering the overall proportion of magnetite in the particles. VSM measurements show that these two coatings lead to a slightly higher saturation magnetization than the citrate. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Gentamicin coated iron oxide nanoparticles as novel antibacterial agents

    Science.gov (United States)

    Bhattacharya, Proma; Neogi, Sudarsan

    2017-09-01

    Applications of different types of magnetic nanoparticles for biomedical purposes started a long time back. The concept of surface functionalization of the iron oxide nanoparticles with antibiotics is a novel technique which paves the path for further application of these nanoparticles by virtue of their property of superparamagnetism. In this paper, we have synthesized novel iron oxide nanoparticles surface functionalized with Gentamicin. The average size of the particles, concluded from the HR-TEM images, came to be around 14 nm and 10 nm for unmodified and modified nanoparticles, respectively. The magnetization curve M(H) obtained for these nanoparticles are typical of superparamagnetic nature and having almost zero values of coercivity and remanance. The release properties of the drug coated nanoparticles were studied; obtaining an S shaped profile, indicating the initial burst effect followed by gradual sustained release. In vitro investigations against various gram positive and gram negative strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis indicated significant antibacterial efficiency of the drug-nanoparticle conjugate. The MIC values indicated that a small amount like 0.2 mg ml-1 of drug capped particles induce about 98% bacterial death. The novelty of the work lies in the drug capping of the nanoparticles, which retains the superparamagnetic nature of the iron oxide nanoparticles and the medical properties of the drug simultaneously, which is found to extremely blood compatible.

  17. Iron oxide and gold nanoparticles in cancer therapy

    International Nuclear Information System (INIS)

    Gotman, Irena; Gutmanas, Elazar Y.; Psakhie, Sergey G.; Lozhkomoev, Aleksandr S.

    2016-01-01

    Continuous research activities in the field of nanomedicine in the past decade have, to a great extent, been focused on nanoparticle technologies for cancer therapy. Gold and iron oxide nanoparticles (NP) are two of the most studied inorganic nanomaterials due to their unique optical and magnetic properties. Both types of NPs are emerging as promising systems for anti-tumor drug delivery and for nanoparticle-mediated thermal therapy of cancer. In thermal therapy, localized heating inside tumors or in proximity of tumor cells can be induced, for example, with Au NPs by radiofrequency ablation heating or conversion of photon energy (photothermal therapy) and in iron oxide magnetic NPs by heat generation through relaxation in an alternating magnetic field (magnetic hyperthermia). Furthermore, the superparamagnetic properties of iron oxide nanoparticles have led to their use as potent MRI (magnetic resonance imaging) contrast agents. Surface modification/coating can produce NPs with tailored and desired properties, such as enhanced blood circulation time, stability, biocompatibility and water solubility. To target nanoparticles to specific tumor cells, NPs should be conjugated with targeting moieties on the surface which bind to receptors or other molecular structures on the cell surface. The article presents several approaches to enhancing the specificity of Au and iron oxide nanoparticles for tumor tissue by appropriate surface modification/functionalization, as well as the effect of these treatments on the saturation magnetization value of iron oxide NPs. The use of other nanoparticles and nanostructures in cancer treatment is also briefly reviewed.

  18. Iron oxide and gold nanoparticles in cancer therapy

    Science.gov (United States)

    Gotman, Irena; Psakhie, Sergey G.; Lozhkomoev, Aleksandr S.; Gutmanas, Elazar Y.

    2016-08-01

    Continuous research activities in the field of nanomedicine in the past decade have, to a great extent, been focused on nanoparticle technologies for cancer therapy. Gold and iron oxide nanoparticles (NP) are two of the most studied inorganic nanomaterials due to their unique optical and magnetic properties. Both types of NPs are emerging as promising systems for anti-tumor drug delivery and for nanoparticle-mediated thermal therapy of cancer. In thermal therapy, localized heating inside tumors or in proximity of tumor cells can be induced, for example, with Au NPs by radiofrequency ablation heating or conversion of photon energy (photothermal therapy) and in iron oxide magnetic NPs by heat generation through relaxation in an alternating magnetic field (magnetic hyperthermia). Furthermore, the superparamagnetic properties of iron oxide nanoparticles have led to their use as potent MRI (magnetic resonance imaging) contrast agents. Surface modification/coating can produce NPs with tailored and desired properties, such as enhanced blood circulation time, stability, biocompatibility and water solubility. To target nanoparticles to specific tumor cells, NPs should be conjugated with targeting moieties on the surface which bind to receptors or other molecular structures on the cell surface. The article presents several approaches to enhancing the specificity of Au and iron oxide nanoparticles for tumor tissue by appropriate surface modification/functionalization, as well as the effect of these treatments on the saturation magnetization value of iron oxide NPs. The use of other nanoparticles and nanostructures in cancer treatment is also briefly reviewed.

  19. Iron oxide and gold nanoparticles in cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gotman, Irena, E-mail: gotman@technion.ac.il; Gutmanas, Elazar Y., E-mail: gutmanas@technion.ac.il [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa, 32000 Israel (Israel); Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Psakhie, Sergey G. [Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); Lozhkomoev, Aleksandr S. [Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation)

    2016-08-02

    Continuous research activities in the field of nanomedicine in the past decade have, to a great extent, been focused on nanoparticle technologies for cancer therapy. Gold and iron oxide nanoparticles (NP) are two of the most studied inorganic nanomaterials due to their unique optical and magnetic properties. Both types of NPs are emerging as promising systems for anti-tumor drug delivery and for nanoparticle-mediated thermal therapy of cancer. In thermal therapy, localized heating inside tumors or in proximity of tumor cells can be induced, for example, with Au NPs by radiofrequency ablation heating or conversion of photon energy (photothermal therapy) and in iron oxide magnetic NPs by heat generation through relaxation in an alternating magnetic field (magnetic hyperthermia). Furthermore, the superparamagnetic properties of iron oxide nanoparticles have led to their use as potent MRI (magnetic resonance imaging) contrast agents. Surface modification/coating can produce NPs with tailored and desired properties, such as enhanced blood circulation time, stability, biocompatibility and water solubility. To target nanoparticles to specific tumor cells, NPs should be conjugated with targeting moieties on the surface which bind to receptors or other molecular structures on the cell surface. The article presents several approaches to enhancing the specificity of Au and iron oxide nanoparticles for tumor tissue by appropriate surface modification/functionalization, as well as the effect of these treatments on the saturation magnetization value of iron oxide NPs. The use of other nanoparticles and nanostructures in cancer treatment is also briefly reviewed.

  20. Structural and magnetic properties of core-shell iron-iron oxide nanoparticles

    DEFF Research Database (Denmark)

    Kuhn, Luise Theil; Bojesen, A.; Timmermann, L.

    2002-01-01

    We present studies of the structural and magnetic properties of core-shell iron-iron oxide nanoparticles. alpha-Fe nanoparticles were fabricated by sputtering and subsequently covered with a protective nanocrystalline oxide shell consisting of either maghaemite (gamma-Fe2O3) or partially oxidized...... magnetite (Fe3O4). We observed that the nanoparticles were stable against further oxidation, and Mossbauer spectroscopy at high applied magnetic fields and low temperatures revealed a stable form of partly oxidized magnetite. The nanocrystalline structure of the oxide shell results in strong canting...... of the spin structure in the oxide shell, which thereby modifies the magnetic properties of the core-shell nanoparticles....

  1. Radiation-induced synthesis of gold, iron-oxide composite nanoparticles

    International Nuclear Information System (INIS)

    Seino, Satoshi; Yamamoto, Takao; Nakagawa, Takashi; Kinoshita, Takuya; Kojima, Takao; Taniguchi, Ryoichi; Okuda, Shuichi

    2007-01-01

    Composite nanoparticles consisting of magnetic iron oxide nanoparticles and gold nanoparticles were synthesized using gamma-rays or electron beam. Ionizing irradiation induces the generation of reducing species inside the aqueous solution, and gold ions are reduced to form metallic Au nanoparticles. The size of Au nanoparticles depended on the dose rate and the concentration of support iron oxide. The gold nanoparticles on iron oxide nanoparticles selectively adsorb biomolecules via Au-S bonding. By using magnetic property of the support iron oxide nanoparticles, the composite nanoparticles are expected as a new type of magnetic nanocarrier for biomedical applications. (author)

  2. Characterization of MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces

    Directory of Open Access Journals (Sweden)

    Venkatakrishnan Krishnan

    2011-01-01

    Full Text Available Abstract In this study, MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces under ambient condition were characterized by scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction analysis (XRD, and X-ray photoelectron spectroscopy (XPS. The radiation fluence used was 0.5 J/cm2 at a pulse repetition rate of 25 MHz with 1 ms interaction time. SEM analysis of the irradiated surfaces showed self-assembled intermingled weblike nanofibrous structure in and around the laser-irradiated spots. Further TEM investigation on this nanostructure revealed that the nanofibrous structure is formed due to aggregation of Au-Si/Si nanoparticles. The XRD peaks at 32.2°, 39.7°, and 62.5° were identified as (200, (211, and (321 reflections, respectively, corresponding to gold silicide. In addition, the observed chemical shift of Au 4f and Si 2p lines in XPS spectrum of the irradiated surface illustrated the presence of gold silicide at the irradiated surface. The generation of Si/Au-Si alloy fibrous nanoparticles aggregate is explained by the nucleation and subsequent condensation of vapor in the plasma plume during irradiation and expulsion of molten material due to high plasma pressure.

  3. Mycosynthesis of iron nanoparticles by Alternaria alternata and its ...

    African Journals Online (AJOL)

    aghomotsegin

    2015-04-08

    Apr 8, 2015 ... Nanotechnology is one of the most emerging fields in the recent years. In the current investigation, we report the biosynthesis of iron nanoparticles (Fe-NPs) employing Alternaria alternata fungus, which is an eco-friendly process for the synthesis of metallic nanoparticles. Fe-NPs were synthesized through.

  4. Mycosynthesis of iron nanoparticles by Alternaria alternata and its ...

    African Journals Online (AJOL)

    Nanotechnology is one of the most emerging fields in the recent years. In the current investigation, we report the biosynthesis of iron nanoparticles (Fe-NPs) employing Alternaria alternata fungus, which is an eco-friendly process for the synthesis of metallic nanoparticles. Fe-NPs were synthesized through the reduction of ...

  5. Stem cell tracking using iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Bull E

    2014-03-01

    Full Text Available Elizabeth Bull,1 Seyed Yazdan Madani,1 Roosey Sheth,1 Amelia Seifalian,1 Mark Green,2 Alexander M Seifalian1,31UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Science, University College London, London, 2Department of Physics, King’s College London, Strand Campus, London, UK; 3Royal Free London National Health Service Foundation Trust Hospital, London, UKAbstract: Superparamagnetic iron oxide nanoparticles (SPIONs are an exciting advancement in the field of nanotechnology. They expand the possibilities of noninvasive analysis and have many useful properties, making them potential candidates for numerous novel applications. Notably, they have been shown that they can be tracked by magnetic resonance imaging (MRI and are capable of conjugation with various cell types, including stem cells. In-depth research has been undertaken to establish these benefits, so that a deeper level of understanding of stem cell migratory pathways and differentiation, tumor migration, and improved drug delivery can be achieved. Stem cells have the ability to treat and cure many debilitating diseases with limited side effects, but a main problem that arises is in the noninvasive tracking and analysis of these stem cells. Recently, researchers have acknowledged the use of SPIONs for this purpose and have set out to establish suitable protocols for coating and attachment, so as to bring MRI tracking of SPION-labeled stem cells into common practice. This review paper explains the manner in which SPIONs are produced, conjugated, and tracked using MRI, as well as a discussion on their limitations. A concise summary of recently researched magnetic particle coatings is provided, and the effects of SPIONs on stem cells are evaluated, while animal and human studies investigating the role of SPIONs in stem cell tracking will be explored.Keywords: stem cells, nanoparticle, magnetic

  6. Effect of surfactant for magnetic properties of iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Haracz, S. [Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89B, 61-614 Poznań (Poland); Hilgendorff, M. [Freie Universität Berlin, Fachbereich Physik, Arnimalle 14, 14195 Berlin (Germany); Rybka, J.D. [Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89B, 61-614 Poznań (Poland); Giersig, M. [Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89B, 61-614 Poznań (Poland); Freie Universität Berlin, Fachbereich Physik, Arnimalle 14, 14195 Berlin (Germany)

    2015-12-01

    Highlights: • Dynamic behavior of magnetic nanoparticles. • Synthesis of iron oxide nanoparticles. • Effect of surfactant for magnetic properties. - Abstract: For different medical applications nanoparticles (NPs) with well-defined magnetic properties have to be used. Coating ligand can change the magnetic moment on the surface of nanostructures and therefore the magnetic behavior of the system. Here we investigated magnetic NPs in a size of 13 nm conjugated with four different kinds of surfactants. The surface anisotropy and the magnetic moment of the system were changed due to the presence of the surfactant on the surface of iron oxide NPs.

  7. Effect of surfactant for magnetic properties of iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Haracz, S.; Hilgendorff, M.; Rybka, J.D.; Giersig, M.

    2015-01-01

    Highlights: • Dynamic behavior of magnetic nanoparticles. • Synthesis of iron oxide nanoparticles. • Effect of surfactant for magnetic properties. - Abstract: For different medical applications nanoparticles (NPs) with well-defined magnetic properties have to be used. Coating ligand can change the magnetic moment on the surface of nanostructures and therefore the magnetic behavior of the system. Here we investigated magnetic NPs in a size of 13 nm conjugated with four different kinds of surfactants. The surface anisotropy and the magnetic moment of the system were changed due to the presence of the surfactant on the surface of iron oxide NPs.

  8. Radiation induced synthesis of gold/iron-oxide composite nanoparticles using high-energy electron beam

    International Nuclear Information System (INIS)

    Seino, Satoshi; Kinoshita, Takuya; Nakagawa, Takashi; Kojima, Takao; Taniguci, Ryoichi; Okuda, Shuichi; Yamamoto, Takao A.

    2008-01-01

    Composite nanoparticles consisting of gold and iron oxide were synthesized in aqueous solution systems by using a high-energy electron beam. The electron irradiation induces radiation-chemical reaction to form metallic gold nanoparticles. These gold nanoparticles were firmly immobilized on the surface of the support iron oxide nanoparticles. Surface of the support iron oxide nanoparticles are almost fully coated with fine gold nanoparticles. The size of these gold nanoparticles depended on the concentrations of gold ions, polymers and iron oxide nanoparticles in the solutions before the irradiation.

  9. Synthesis, Characterization, and Cytotoxicity of Iron Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    S. Kanagesan

    2013-01-01

    Full Text Available In order to study the response of human breast cancer cells' exposure to nanoparticle, iron oxide (α-Fe2O3 nanoparticles were synthesized by a simple low temperature combustion method using Fe(NO33·9H2O as raw material. X-ray diffraction studies confirmed that the resultant powders are pure α-Fe2O3. Transmission electron microscopy study revealed the spherical shape of the primary particles, and the size of the iron oxide nanoparticles is in the range of 19 nm. The magnetic hysteresis loops demonstrated that the sample exposed ferromagnetic behaviors with a relatively low coercivity. The cytotoxicity of α-Fe2O3 nanoparticle was also evaluated on human breast cancer cells to address the current deficient knowledge of cellular response to nanoparticle exposure.

  10. Promising iron oxide-based magnetic nanoparticles in biomedical engineering.

    Science.gov (United States)

    Tran, Phuong Ha-Lien; Tran, Thao Truong-Dinh; Vo, Toi Van; Lee, Beom-Jin

    2012-12-01

    For the past few decades biomedical engineering has imprinted its significant impact on the map of science through its wide applications on many other fields. An important example obviously proving this fact is the versatile application of magnetic nanoparticles in theranostics. Due to preferable properties such as biocompatibility, non-toxicity compared to other metal derivations, iron oxide-based magnetic nanoparticles was chosen to be addressed in this review. Aim of this review is to give the readers a whole working window of these magnetic nanoparticles in the current context of science. Thus, preparation of magnetic iron oxide nanoparticles with the so-far techniques, methods of characterizing the nanoparticles as well as their most recent biomedical applications will be stated.

  11. Magnesium and iron nanoparticles production using microorganisms and various salts

    Science.gov (United States)

    Kaul, R. K.; Kumar, P.; Burman, U.; Joshi, P.; Agrawal, A.; Raliya, R.; Tarafdar, J. C.

    2012-09-01

    Response of five fungi and two bacteria to different salts of magnesium and iron for production of nanoparticles was studied. Pochonia chlamydosporium, and Aspergillus fumigatus were exposed to three salts of magnesium while Curvularia lunata, Chaetomium globosum, A. fumigatus, A. wentii and the bacteria Alcaligenes faecalis and Bacillus coagulans were exposed to two salts of iron for nanoparticle production. The results revealed that P. chlamydosporium induces development of extracellular nanoparticles in MgCl2 solution while A. fumigatus produces also intracellular nanoparticles when exposed to MgSO4 solution. C. globosum was found as the most effective in producing nanoparticles when exposed to Fe2O3 solution. The FTIR analysis of the nanoparticles obtained from Fe2O3 solution showed the peaks similar to iron (Fe). In general, the species of the tested microbes were selective to different chemicals in their response for synthesis of nanoparticles. Further studies on their characterization and improving the efficiency of promising species of fungi need to be undertaken before tapping their potential as nanonutrients for plants.

  12. Fluorescence from metallic silver and iron nanoparticles prepared by exploding wire technique

    OpenAIRE

    Alqudami, Abdullah; Annapoorni, S.

    2006-01-01

    The observation of intense visible fluorescence from silver and iron nanoparticles in different solution phases and surface capping is reported here. Metallic silver and iron nanoparticles were obtained by exploding pure silver and iron wires in pure water. Bovine serum albumin protein adsorption on the silver nanoparticles showed an enhanced fluorescence. The presence of poly-vinyl pyrrolidone polymer in the exploding medium resulted in a stabilized growth of iron nanoparticles with enhanced...

  13. In vitro toxicity assessment of chitosan oligosaccharide coated iron oxide nanoparticles

    OpenAIRE

    Shukla, Sudeep; Jadaun, Alka; Arora, Vikas; Sinha, Raj Kumar; Biyani, Neha; Jain, V.K.

    2014-01-01

    Iron oxide nanoparticles (INPs) have potential biological, biomedical and environmental applications. These applications require surface modification of the iron oxide nanoparticles, which makes it non-toxic, biocompatible, stable and non-agglomerative in natural and biological surroundings. In the present study, iron oxide nanoparticles (INPs) and chitosan oligosaccharide coated iron oxide nanoparticles (CSO-INPs) were synthesized to evaluate the effect of surface coating on the stability an...

  14. Exchange Bias Effects in Iron Oxide-Based Nanoparticle Systems

    Science.gov (United States)

    Phan, Manh-Huong; Alonso, Javier; Khurshid, Hafsa; Lampen-Kelley, Paula; Chandra, Sayan; Stojak Repa, Kristen; Nemati, Zohreh; Das, Raja; Iglesias, Óscar; Srikanth, Hariharan

    2016-01-01

    The exploration of exchange bias (EB) on the nanoscale provides a novel approach to improving the anisotropic properties of magnetic nanoparticles for prospective applications in nanospintronics and nanomedicine. However, the physical origin of EB is not fully understood. Recent advances in chemical synthesis provide a unique opportunity to explore EB in a variety of iron oxide-based nanostructures ranging from core/shell to hollow and hybrid composite nanoparticles. Experimental and atomistic Monte Carlo studies have shed light on the roles of interface and surface spins in these nanosystems. This review paper aims to provide a thorough understanding of the EB and related phenomena in iron oxide-based nanoparticle systems, knowledge of which is essential to tune the anisotropic magnetic properties of exchange-coupled nanoparticle systems for potential applications. PMID:28335349

  15. Synthesis of pure iron magnetic nanoparticles in large quantity

    International Nuclear Information System (INIS)

    Tiwary, C S; Kashyap, S; Chattopadhyay, K; Biswas, K

    2013-01-01

    Free nanoparticles of iron (Fe) and their colloids with high saturation magnetization are in demand for medical and microfluidic applications. However, the oxide layer that forms during processing has made such synthesis a formidable challenge. Lowering the synthesis temperature decreases rate of oxidation and hence provides a new way of producing pure metallic nanoparticles prone to oxidation in bulk amount (large quantity). In this paper we have proposed a methodology that is designed with the knowledge of thermodynamic imperatives of oxidation to obtain almost oxygen-free iron nanoparticles, with or without any organic capping by controlled milling at low temperatures in a specially designed high-energy ball mill with the possibility of bulk production. The particles can be ultrasonicated to produce colloids and can be bio-capped to produce transparent solution. The magnetic properties of these nanoparticles confirm their superiority for possible biomedical and other applications. (paper)

  16. Environmental Transmission Electron Microscopy (ETEM) Studies of Single Iron Nanoparticle Carburization in Synthesis Gas

    DEFF Research Database (Denmark)

    Liu, Xi; Zhang, Chenghua; Li, Yongwang

    2017-01-01

    Structuralevolution of iron nanoparticles involving the formationand growth of iron carbide nuclei in the iron nanoparticle was directlyvisualized at the atomic level, using environmental transmission electronmicroscopy (TEM) under reactive conditions mimicking Fischer–Tropschsynthesis. Formation...... and electronenergy-loss spectra provides a detailed picture from initial activationto final degradation of iron under synthesis gas....

  17. From iron coordination compounds to metal oxide nanoparticles.

    Science.gov (United States)

    Iacob, Mihail; Racles, Carmen; Tugui, Codrin; Stiubianu, George; Bele, Adrian; Sacarescu, Liviu; Timpu, Daniel; Cazacu, Maria

    2016-01-01

    Various types, shapes and sizes of iron oxide nanoparticles were obtained depending on the nature of the precursor, preparation method and reaction conditions. The mixed valence trinuclear iron acetate, [Fe 2 III Fe II O(CH 3 COO) 6 (H 2 O) 3 ]·2H 2 O (FeAc1), μ 3 -oxo trinuclear iron(III) acetate, [Fe 3 O(CH 3 COO) 6 (H 2 O) 3 ]NO 3 ∙4H 2 O (FeAc2), iron furoate, [Fe 3 O(C 4 H 3 OCOO) 6 (CH 3 OH) 3 ]NO 3 ∙2CH 3 OH (FeF), iron chromium furoate, FeCr 2 O(C 4 H 3 OCOO) 6 (CH 3 OH) 3 ]NO 3 ∙2CH 3 OH (FeCrF), and an iron complex with an original macromolecular ligand (FePAZ) were used as precursors for the corresponding oxide nanoparticles. Five series of nanoparticle samples were prepared employing either a classical thermal pathway (i.e., thermal decomposition in solution, solvothermal method, dry thermal decomposition/calcination) or using a nonconventional energy source (i.e., microwave or ultrasonic treatment) to convert precursors into iron oxides. The resulting materials were structurally characterized by wide-angle X-ray diffraction and Fourier transform infrared, Raman, energy-dispersive X-ray, and X-ray fluorescence spectroscopies, as well as thermogravimetric analysis. The morphology was characterized by transmission electron microscopy, atomic force microscopy and dynamic light scattering. The parameters were varied within each route to fine tune the size and shape of the formed nanoparticles.

  18. From iron coordination compounds to metal oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Mihail Iacob

    2016-12-01

    Full Text Available Various types, shapes and sizes of iron oxide nanoparticles were obtained depending on the nature of the precursor, preparation method and reaction conditions. The mixed valence trinuclear iron acetate, [Fe2IIIFeIIO(CH3COO6(H2O3]·2H2O (FeAc1, μ3-oxo trinuclear iron(III acetate, [Fe3O(CH3COO6(H2O3]NO3∙4H2O (FeAc2, iron furoate, [Fe3O(C4H3OCOO6(CH3OH3]NO3∙2CH3OH (FeF, iron chromium furoate, FeCr2O(C4H3OCOO6(CH3OH3]NO3∙2CH3OH (FeCrF, and an iron complex with an original macromolecular ligand (FePAZ were used as precursors for the corresponding oxide nanoparticles. Five series of nanoparticle samples were prepared employing either a classical thermal pathway (i.e., thermal decomposition in solution, solvothermal method, dry thermal decomposition/calcination or using a nonconventional energy source (i.e., microwave or ultrasonic treatment to convert precursors into iron oxides. The resulting materials were structurally characterized by wide-angle X-ray diffraction and Fourier transform infrared, Raman, energy-dispersive X-ray, and X-ray fluorescence spectroscopies, as well as thermogravimetric analysis. The morphology was characterized by transmission electron microscopy, atomic force microscopy and dynamic light scattering. The parameters were varied within each route to fine tune the size and shape of the formed nanoparticles.

  19. Synthesis and Stability of Iron Nanoparticles for Lunar Environment Studies

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2009-01-01

    Simulant of lunar dust is needed when researching the lunar environment. However, unlike the true lunar dust, today s simulants do not contain nanophase iron. Two different processes have been developed to fabricate nanophase iron to be used as part of the lunar dust simulant: (1) Sequentially treating a mixture of ferric chloride, fluorinated carbon, and soda lime glass beads at about 300 C in nitrogen, at room temperature in air, and then at 1050 C in nitrogen. The product includes glass beads that are grey in color, can be attracted by a magnet, and contain alpha-iron nanoparticles (which seem to slowly lose their lattice structure in ambient air during a period of 12 months). This product may have some similarity to the lunar glassy regolith that contains Fe(sup 0). (2) Heating a mixture of carbon black and a lunar simulant (a mixed metal oxide that includes iron oxide) at 1050 C in nitrogen. This process simulates lunar dust reaction to the carbon in a micrometeorite at the time of impact. The product contains a chemically modified simulant that can be attracted by a magnet and has a surface layer whose iron concentration increased during the reaction. The iron was found to be alpha-iron and Fe3O4 nanoparticles, which appear to grow after the fabrication process, but stabilizes after 6 months of ambient air storage.

  20. Synthesis of Monodisperse Iron Oxide Nanoparticles without Surfactants

    Directory of Open Access Journals (Sweden)

    Xiao-Chen Yang

    2014-01-01

    Full Text Available Monodisperse iron oxide nanoparticles could be successfully synthesized with two kinds of precipitants through a precipitation method. As-prepared nanoparticles in the size around 10 nm with regular spherical-like shape were achieved by adjusting pH values. NaOH and NH3·H2O were used as two precipitants for comparison. The average size of nanoparticles with NH3·H2O precipitant got smaller and represented better dispersibility, while nanoparticles with NaOH precipitant represented better magnetic property. This work provided a simple method without using any organic solvents, organic metal salts, or surfactants which could easily obtain monodisperse nanoparticles with tunable morphology.

  1. Environmental transformations and ecological effects of iron-based nanoparticles.

    Science.gov (United States)

    Lei, Cheng; Sun, Yuqing; Tsang, Daniel C W; Lin, Daohui

    2018-01-01

    The increasing application of iron-based nanoparticles (NPs), especially high concentrations of zero-valent iron nanoparticles (nZVI), has raised concerns regarding their environmental behavior and potential ecological effects. In the environment, iron-based NPs undergo physical, chemical, and/or biological transformations as influenced by environmental factors such as pH, ions, dissolved oxygen, natural organic matter (NOM), and biotas. This review presents recent research advances on environmental transformations of iron-based NPs, and articulates their relationships with the observed toxicities. The type and extent of physical, chemical, and biological transformations, including aggregation, oxidation, and bio-reduction, depend on the properties of NPs and the receiving environment. Toxicities of iron-based NPs to bacteria, algae, fish, and plants are increasingly observed, which are evaluated with a particular focus on the underlying mechanisms. The toxicity of iron-based NPs is a function of their properties, tolerance of test organisms, and environmental conditions. Oxidative stress induced by reactive oxygen species is considered as the primary toxic mechanism of iron-based NPs. Factors influencing the toxicity of iron-based NPs are addressed and environmental transformations play a significant role, for example, surface oxidation or coating by NOM generally lowers the toxicity of nZVI. Research gaps and future directions are suggested with an aim to boost concerted research efforts on environmental transformations and toxicity of iron-based NPs, e.g., toxicity studies of transformed NPs in field, expansion of toxicity endpoints, and roles of laden contaminants and surface coating. This review will enhance our understanding of potential risks of iron-based NPs and proper uses of environmentally benign NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Preparation of Iron Nanoparticles by Selective Leaching Method

    Czech Academy of Sciences Publication Activity Database

    Michalcová, A.; Vojtěch, D.; Kubatík, Tomáš František; Stehlíková, K.; Brabec, F.; Marek, I.

    2015-01-01

    Roč. 128, č. 4 (2015), s. 640-642 ISSN 0587-4246. [International Symposium on Physics of Materials (ISPMA) /13./. Prague, 31.08.2014-04.09.2014] Institutional support: RVO:61389021 Keywords : Iron nanoparticles * selective leaching method Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 0.525, year: 2015

  3. Iron nanoparticles prepared from natural ferrihydrite precursors: kinetics and properties

    Czech Academy of Sciences Publication Activity Database

    Schneeweiss, Oldřich; Filip, J.; David, Bohumil; Zbořil, R.; Mašláň, M.

    2011-01-01

    Roč. 13, č. 11 (2011), s. 5677-5684 ISSN 1388-0764. [ International Conference on Nanostructured Materials (NANO 2010) /10./. Rome, 13.09.2010-17.09.2010] Institutional research plan: CEZ:AV0Z20410507 Keywords : Iron nanoparticles * Ferrihydrite * Reduction * Hydrogen * Magnetic moment * Activation enthalpy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.287, year: 2011

  4. Thermal Plasma Synthesis of Superparamagnetic Iron Oxide Nanoparticles

    NARCIS (Netherlands)

    Lei, P.Y.; Boies, A.M.; Calder, S.A.; Girshick, S.L.

    2012-01-01

    Superparamagnetic iron oxide nanoparticles were synthesized by injecting ferrocene vapor and oxygen into an argon/helium DC thermal plasma. Size distributions of particles in the reactor exhaust were measured online using an aerosol extraction probe interfaced to a scanning mobility particle sizer,

  5. Identification of Spinel Iron Oxide Nanoparticles by 57Fe NMR

    Directory of Open Access Journals (Sweden)

    SangGap Lee

    2011-12-01

    Full Text Available We have synthesized and studied monodisperse iron oxide nanoparticles of smaller than 10 nm to identify between the two spinel phases, magnetite and maghemite. It is shown that 57Fe NMR spectroscopy is a promising tool for distinguishing between the two phases.

  6. Thermosensitive liposomes entrapping iron oxide nanoparticles for controllable drug release

    International Nuclear Information System (INIS)

    Tai, L-A; Wang, Y-C; Wang, Y-J; Yang, C-S; Tsai, P-J; Lo, L-W

    2009-01-01

    Iron oxide nanoparticles can serve as a heating source upon alternative magnetic field (AMF) exposure. Iron oxide nanoparticles can be mixed with thermosensitive nanovehicles for hyperthermia-induced drug release, yet such a design and mechanism may not be suitable for controllable drug release applications in which the tissues are susceptible to environmental temperature change such as brain tissue. In the present study, iron oxide nanoparticles were entrapped inside of thermosensitive liposomes for AMF-induced drug release while the environmental temperature was maintained at a constant level. Carboxyfluorescein was co-entrapped with the iron oxide nanoparticles in the liposomes as a model compound for monitoring drug release and environmental temperature was maintained with a water circulator jacket. These experiments have been successfully performed in solution, in phantom and in anesthetized animals. Furthermore, the thermosensitive liposomes were administered into rat forearm skeletal muscle, and the release of carboxylfluorescein triggered by the external alternative magnetic field was monitored by an implanted microdialysis perfusion probe with an on-line laser-induced fluorescence detector. In the future such a device could be applied to simultaneous magnetic resonance imaging and non-invasive drug release in temperature-sensitive applications.

  7. Radioiodination of cyclin dependent kinase inhibitor Olomoucine loaded Fe rate at Au nanoparticle and evaluation of the therapeutic efficacy on cancerous cells

    Energy Technology Data Exchange (ETDEWEB)

    Takan, Gokhan; Guldu, Ozge Kozgus; Medine, Emin Ilker [Ege Univ., Izmir (Turkey). Dept. of Nuclear Applications

    2017-06-01

    Magnetic nanoparticles have promising biomedical applications such as drug delivery, novel therapeutics and diagnostic imaging. Magnetic drug delivery combination works on the delivery of magnetic nanoparticles loaded with drug to the target tissue by means of an external magnetic field. Gold coated iron oxide (Fe rate at Au) nanoparticles can provide useful surface chemistry and biological reactivity. Covalent conjugation to the Fe rate at Au nanoparticles through cleavable linkages can be used to deliver drugs to tumor cells, then the drug can be released by an external. In this paper, purine based cyclin dependent kinases (CDKs) inhibitor Olomoucine (Olo) [2-(Hydroxyethylamino)-6-benzylamino-9-methylpurine] was loaded on gold coated iron oxide (Fe rate at Au) nanoparticles and radiolabeled with {sup 131}I to combine magnetic targeted drug delivery and radiotherapy. Fe rate at Au nanoparticles were synthesized by microemulsion method. The characterization of nanoparticles was examined by TEM, VSM and XRD. Amine activation was utilized by cysteamine hydrochloride and then CDI was used for conjugation of Olomoucine. Antiproliferative effect and cytotoxicity of Olomoucine loaded Fe rate at Au nanoparticles (Fe rate at Au-Olo) were investigated on MCF7 and A549 cell lines. Proliferation rate was decreased while uptake of Fe rate at Au-Olo on both cell lines was high in comparison with Olomoucine. Also, enhanced incorporation ratio was observed under external magnetic field.

  8. X-Ray Photoelectron Spectroscopic Characterization of Iron Oxide Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Radu, T., E-mail: Teodora.Radu@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293, Cluj Napoca (Romania); Iacovita, C. [Department of Pharmaceutical Physics-Biophysics, Faculty of Pharmacy, “Iuliu Hatieganu” University of Medicine and Pharmacy, 400349, Cluj-Napoca (Romania); Benea, D. [Faculty of Physics, Babes Bolyai University, 400271, Cluj-Napoca (Romania); Turcu, R. [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293, Cluj Napoca (Romania)

    2017-05-31

    Highlights: • Characterization of three types of iron oxides magnetic nanoparticles. • A correlation between valence band XPS and the degree of iron oxidation is proposed. • Theoretical contributions of Fe in tetragonal and octahedral environment are shown. - Abstract: We report X-ray photoelectron spectroscopy (XPS) results on iron oxide magnetic nanoparticle (Fe{sub 3}O{sub 4}) synthesized using solvothermal reduction in the presence of polyethylene glycol. The magnetite obtained was employed as precursor for the synthesis of γ-Fe{sub 2}O{sub 3} (by oxygen dissociation) which in turn was transformed into α-Fe{sub 2}O{sub 3}. We confirmed the magnetite, maghemite and hematite structure by Fourier Transformed Spectroscopy (FTIR) and X-ray diffraction (XRD). The analysis of the XPS core level and valence band (VB) photoemission spectra for all investigated samples is discussed in terms of the degree of iron oxidation. This is of fundamental importance to better understand the electronic structure of the obtained iron oxide nanoparticles in order to control and improve their quality for specific biomedical applications. Moreover, theoretical band structure calculations are performed for magnetite and the separate contributions of Fe in tetragonal and octahedral environment are shown.

  9. Mercury removal in wastewater by iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Vélez, E; Campillo, G E; Morales, G; Hincapié, C; Osorio, J; Arnache, O; Uribe, J I; Jaramillo, F

    2016-01-01

    Mercury is one of the persistent pollutants in wastewater; it is becoming a severe environmental and public health problem, this is why nowadays its removal is an obligation. Iron oxide nanoparticles are receiving much attention due to their properties, such as: great biocompatibility, ease of separation, high relation of surface-area to volume, surface modifiability, reusability, excellent magnetic properties and relative low cost. In this experiment, Fe 3 O 4 and γ-Fe 2 O 3 nanoparticles were synthesized using iron salts and NaOH as precipitation agents, and Aloe Vera as stabilizing agent; then these nanoparticles were characterized by three different measurements: first, using a Zetasizer Nano ZS for their size estimation, secondly UV-visible spectroscopy which showed the existence of resonance of plasmon at λ max ∼360 nm, and lastly by Scanning Electron Microscopy (SEM) to determine nanoparticles form. The results of this characterization showed that the obtained Iron oxides nanoparticles have a narrow size distribution (∼100nm). Mercury removal of 70% approximately was confirmed by atomic absorption spectroscopy measurements. (paper)

  10. Linear-chain assemblies of iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Dhak, Prasanta; Kim, Min-Kwan; Lee, Jae Hyeok; Kim, Miyoung; Kim, Sang-Koog, E-mail: sangkoog@snu.ac.kr

    2017-07-01

    Highlights: • Hydrothermal synthesis of pure phase 200 nm Fe{sub 3}O{sub 4} nanoparticles. • Studies of linear-chain assemblies of iron oxide nanosphere by FESEM. • Micromagnetic simulations showed the presence of 3D vortex states. • The B.E. for different numbers of particles in linear chain assemblies were calculated. - Abstract: We synthesized iron oxide nanoparticles using a simple hydrothermal approach and found several types of segments of their linear-chain self-assemblies as observed by field emission scanning electron microscopy. X-ray diffraction and transmission electron microscopy measurements confirm a well-defined single-phase FCC structure. Vibrating sample magnetometry measurements exhibit a ferromagnetic behavior. Micromagnetic numerical simulations show magnetic vortex states in the nanosphere model. Also, calculations of binding energies for different numbers of particles in the linear-chain assemblies explain a possible mechanism responsible for the self-assemblies of segments of the linear chains of nanoparticles. This work offers a step towards linear-chain self-assemblies of iron oxide nanoparticles and the effect of magnetic vortex states in individual nanoparticles on their binding energy.

  11. Synthesis of carbon-coated iron nanoparticles by detonation technique

    International Nuclear Information System (INIS)

    Sun, Guilei; Li, Xiaojie; Wang, Qiquan; Yan, Honghao

    2010-01-01

    Carbon-coated iron nanoparticles were synthesized by detonating a mixture of ferrocene, naphthalene and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in an explosion vessel under low vacuum conditions (8.1 kPa). The RDX functioned as an energy source for the decomposition of ferrocene and naphthalene. The carbon-coated iron nanoparticles were formed as soot-like deposits on the inner surface of the reactor, which were characterized by XRD, TEM, HRTEM, Raman spectroscopy and vibrating sample magnetometer. And a portion of the detonation soot was treated with hydrochloric acid. The product was carbon-coated nanoparticles in perfect core-shell structures with graphitic shells and bcc-Fe cores. The detonation technique offers an energy-saving route to the synthesis of carbon-coated nanomaterials.

  12. Study of hematite-iron phase transformation during iron-carbon core-shell nanoparticles synthesis and investigation of their magnetic and microwave properties

    OpenAIRE

    Omid Khani; Morteza Zargar Shoushtari; Mohammad Jazirehpour; Mansoor Farbod

    2017-01-01

    The structural properties and microwave absorption capability of the iron nanoparticles and iron-carbon core-shell nanoparticles have been studied, in the present paper. The investigated nanoparticles were synthesized by hydrothermal route and by reduction of hematite nanoparticles during annealing in argon-hydrogen atmosphere. Hematite-iron phase transformation during the reduction process has been studied by X-ray diffraction (XRD). XRD patterns showed that in iron nanoparticles, hematite-i...

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

    Directory of Open Access Journals (Sweden)

    Ali A

    2016-08-01

    Full Text Available Attarad Ali,1 Hira Zafar,1 Muhammad Zia,1 Ihsan ul Haq,2 Abdul Rehman Phull,3 Joham Sarfraz Ali,1 Altaf Hussain4 1Department of Biotechnology, 2Department of Pharmacy, Quaid-i-Azam University, Islamabad, Pakistan; 3Department of Biology, Kongju National University, Kongju, South Korea; 4Department of Materials Science and Engineering, Institute of Space Technology, Islamabad, Pakistan Abstract: 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. Keywords: superparamagnetism, iron oxide nanoparticles, surfactants, hyperthermia, biodistribution, bioelimination

  14. Genotoxicity of Superparamagnetic Iron Oxide Nanoparticles in Granulosa Cells

    Directory of Open Access Journals (Sweden)

    Marina Pöttler

    2015-11-01

    Full Text Available Nanoparticles that are aimed at targeting cancer cells, but sparing healthy tissue provide an attractive platform of implementation for hyperthermia or as carriers of chemotherapeutics. According to the literature, diverse effects of nanoparticles relating to mammalian reproductive tissue are described. To address the impact of nanoparticles on cyto- and genotoxicity concerning the reproductive system, we examined the effect of superparamagnetic iron oxide nanoparticles (SPIONs on granulosa cells, which are very important for ovarian function and female fertility. Human granulosa cells (HLG-5 were treated with SPIONs, either coated with lauric acid (SEONLA only, or additionally with a protein corona of bovine serum albumin (BSA; SEONLA-BSA, or with dextran (SEONDEX. Both micronuclei testing and the detection of γH2A.X revealed no genotoxic effects of SEONLA-BSA, SEONDEX or SEONLA. Thus, it was demonstrated that different coatings of SPIONs improve biocompatibility, especially in terms of genotoxicity towards cells of the reproductive system.

  15. Iron oxide nanoparticles in different modifications for antimicrobial phototherapy

    Science.gov (United States)

    Tuchina, Elena S.; Kozina, Kristina V.; Shelest, Nikita A.; Kochubey, Vyacheslav I.; Tuchin, Valery V.

    2014-03-01

    The main goal of this study was to investigate the sensitivity of microorganisms to combined action of blue light and iron oxide nanoparticles. Two strains of Staphylococcus aureus - methicillin-sensitive and meticillin-resistant were used. As a blue light source LED with spectral maximum at 405 nm was taken. The light exposure was ranged from 5 to 30 min. The Fe2O3 (diameter ˜27 nm), Fe3O4 nanoparticles (diameter ˜19 nm), and composite Fe2O3/TiO2 nanoparticles (diameter ˜100 nm) were synthesized. It was shown that irradiation by blue light caused from 20% to 88% decrease in the number of microorganisms treated with nanoparticles. Morphological changes in bacterial cells after phototreatment were analyzed using scanning electron microscope.

  16. Size-dependent magnetic properties of iron oxide nanoparticles

    Science.gov (United States)

    Patsula, Vitalii; Moskvin, Maksym; Dutz, Silvio; Horák, Daniel

    2016-01-01

    Uniform iron oxide nanoparticles in the size range from 10 to 24 nm and polydisperse 14 nm iron oxide particles were prepared by thermal decomposition of Fe(III) carboxylates in the presence of oleic acid and co-precipitation of Fe(II) and Fe(III) chlorides by ammonium hydroxide followed by oxidation, respectively. While the first method produced hydrophobic oleic acid coated particles, the second one formed hydrophilic, but uncoated, nanoparticles. To make the iron oxide particles water dispersible and colloidally stable, their surface was modified with poly(ethylene glycol) and sucrose, respectively. Size and size distribution of the nanoparticles was determined by transmission electron microscopy, dynamic light scattering and X-ray diffraction. Surface of the PEG-functionalized and sucrose-modified iron oxide particles was characterized by Fourier transform infrared (FT-IR) and Raman spectroscopy and thermogravimetric analysis (TGA). Magnetic properties were measured by means of vibration sample magnetometry and specific absorption rate in alternating magnetic fields was determined calorimetrically. It was found, that larger ferrimagnetic particles showed higher heating performance than smaller superparamagnetic ones. In the transition range between superparamagnetism and ferrimagnetism, samples with a broader size distribution provided higher heating power than narrow size distributed particles of comparable mean size. Here presented particles showed promising properties for a possible application in magnetic hyperthermia.

  17. Iron and iron oxide nanoparticles obtained by ultra-short laser ablation in liquid

    Energy Technology Data Exchange (ETDEWEB)

    De Bonis, A., E-mail: angela.debonis@unibas.it [Dipartimento di Scienze, Università della Basilicata, Viale dell’Ateneo Lucano, 10 – 85100 Potenza (Italy); Lovaglio, T.; Galasso, A. [Dipartimento di Scienze, Università della Basilicata, Viale dell’Ateneo Lucano, 10 – 85100 Potenza (Italy); Santagata, A. [CNR-ISM, U.O.S di Potenza, Zona Industriale di Tito, 85050 Tito Scalo (PZ) (Italy); Teghil, R. [Dipartimento di Scienze, Università della Basilicata, Viale dell’Ateneo Lucano, 10 – 85100 Potenza (Italy)

    2015-10-30

    Highlights: • Laser ablation of a iron target in water and acetone performed by an ultra-short laser source has been reported. • The size distributions of the obtained nanoparticles have been related to the ablation dynamics. • The formation of a graphitic shell prevents the oxidation of the iron nanoparticles. - Abstract: Laser ablation of an iron target in water and acetone has been carried out using a frequency doubled Nd:glass laser source (pulse duration of 250 fs and frequency repetition rate of 10 Hz). The observation of the nanostructures formed in the laser irradiated region of the metallic target and fast shadowgraphic analysis of the laser induced cavitation bubble have been performed in order to correlate the size distribution of the obtained nanoparticles to the dynamics of the ablation process. The composition, morphology and oxidation state of the synthesized nanoproducts have been investigated by XPS (X-ray Photoelectron Spectroscopy), TEM (Transmission Electron Microscopy) and microRaman spectroscopy. The experimental data support a relationship between the nanoparticles size distribution and the femtosecond laser ablation mechanism, while the chemical and structural characteristics of the nanoparticles can be tuned by varying the liquid medium.

  18. Iron and iron oxide nanoparticles obtained by ultra-short laser ablation in liquid

    International Nuclear Information System (INIS)

    De Bonis, A.; Lovaglio, T.; Galasso, A.; Santagata, A.; Teghil, R.

    2015-01-01

    Highlights: • Laser ablation of a iron target in water and acetone performed by an ultra-short laser source has been reported. • The size distributions of the obtained nanoparticles have been related to the ablation dynamics. • The formation of a graphitic shell prevents the oxidation of the iron nanoparticles. - Abstract: Laser ablation of an iron target in water and acetone has been carried out using a frequency doubled Nd:glass laser source (pulse duration of 250 fs and frequency repetition rate of 10 Hz). The observation of the nanostructures formed in the laser irradiated region of the metallic target and fast shadowgraphic analysis of the laser induced cavitation bubble have been performed in order to correlate the size distribution of the obtained nanoparticles to the dynamics of the ablation process. The composition, morphology and oxidation state of the synthesized nanoproducts have been investigated by XPS (X-ray Photoelectron Spectroscopy), TEM (Transmission Electron Microscopy) and microRaman spectroscopy. The experimental data support a relationship between the nanoparticles size distribution and the femtosecond laser ablation mechanism, while the chemical and structural characteristics of the nanoparticles can be tuned by varying the liquid medium.

  19. Gold coated metal nanostructures grown by glancing angle deposition and pulsed electroplating

    Science.gov (United States)

    Grüner, Christoph; Reeck, Pascal; Jacobs, Paul-Philipp; Liedtke, Susann; Lotnyk, Andriy; Rauschenbach, Bernd

    2018-05-01

    Nickel based nanostructures are grown by glancing angle deposition (GLAD) on flat and pre-patterned substrates. These fabricated porous thin films were subsequently coated by pulsed electroplating with gold. The morphology and conformity of the gold coating were investigated by scanning electron microscopy and X-ray diffraction. Controlled growth of closed gold layers on the nanostructures could be achieved, while the open-pore structure of the nanosculptured thin films was preserved. Such gold coated nanostructures are a candidate for optical sensing and catalysis applications. The demonstrated method can be applied for numerous material combinations, allowing to provide GLAD thin films with new surface properties.

  20. Revealing the interparticle magnetic interactions of iron oxide nanoparticles-carbon nanotubes hybrid materials

    NARCIS (Netherlands)

    Douvalis, A.P.; Georgakilas, V.; Tsoufis, T.; Gournis, D.; Kooi, B.; Bakas, T.

    2010-01-01

    Spinel iron oxide nanoparticles capped with organic molecules have been successfully prepared and used to produce iron oxide nanoparticles-single wall carbon nanotubes hybrid materials, which were characterized by a number of experimental techniques. The nanoparticles in both samples have an average

  1. Iron oxide nanoparticles stabilized inside highly ordered ...

    Indian Academy of Sciences (India)

    Nanosized iron oxide, a moderately large band-gap semiconductor and an essential component of optoelectrical and magnetic devices, has been prepared successfully inside the restricted internal pores of mesoporous silica material through in-situ reduction during impregnation. The samples were characterized by ...

  2. Iron oxide nanoparticles stabilized inside highly ordered ...

    Indian Academy of Sciences (India)

    Abstract. Nanosized iron oxide, a moderately large band-gap semiconductor and an essential component of optoelectrical and magnetic devices, has been prepared success- fully inside the restricted internal pores of mesoporous silica material through in-situ reduction during impregnation. The samples were characterized ...

  3. Iron oxide nanoparticles stabilized inside highly ordered ...

    Indian Academy of Sciences (India)

    extensively in recent times because of their technological and fundamental scien- tific importance [1]. These nanomaterials exhibit very interesting electrical, opti- cal, magnetic, chemical and related surface properties, which is entirely different. [2] from the respective bulk materials. The fabrication of low valent iron nanopar-.

  4. Targeted magnetic iron oxide nanoparticles for tumor imaging and therapy

    Directory of Open Access Journals (Sweden)

    Xiang-Hong Peng

    2008-10-01

    Full Text Available Xiang-Hong Peng1,4, Ximei Qian2,4, Hui Mao3,4, Andrew Y Wang5, Zhuo (Georgia Chen1,4, Shuming Nie2,4, Dong M Shin1,4*1Department of Medical Oncology/Hematology; 2Department of Biomedical Engineering; 3Department of Radiology; 4Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA; 5Ocean Nanotech, LLC, Fayetteville, AR, USAAbstract: Magnetic iron oxide (IO nanoparticles with a long blood retention time, biodegradability and low toxicity have emerged as one of the primary nanomaterials for biomedical applications in vitro and in vivo. IO nanoparticles have a large surface area and can be engineered to provide a large number of functional groups for cross-linking to tumor-targeting ligands such as monoclonal antibodies, peptides, or small molecules for diagnostic imaging or delivery of therapeutic agents. IO nanoparticles possess unique paramagnetic properties, which generate significant susceptibility effects resulting in strong T2 and T*2 contrast, as well as T1 effects at very low concentrations for magnetic resonance imaging (MRI, which is widely used for clinical oncology imaging. We review recent advances in the development of targeted IO nanoparticles for tumor imaging and therapy.Keywords: iron oxide nanoparticles, tumor imaging, MRI, therapy

  5. Multifunctional gold coated thermo-sensitive liposomes for multimodal imaging and photo-thermal therapy of breast cancer cells

    Science.gov (United States)

    Rengan, Aravind Kumar; Jagtap, Madhura; de, Abhijit; Banerjee, Rinti; Srivastava, Rohit

    2013-12-01

    Plasmon resonant gold nanoparticles of various sizes and shapes have been extensively researched for their applications in imaging, drug delivery and photothermal therapy (PTT). However, their ability to degrade after performing the required function is essential for their application in healthcare. When combined with biodegradable liposomes, they appear to have better degradation capabilities. They degrade into smaller particles of around 5 nm that are eligible candidates for renal clearance. Distearoyl phosphatidyl choline : cholesterol (DSPC : CHOL, 8 : 2 wt%) liposomes have been synthesized and coated with gold by in situ reduction of chloro-auric acid. These particles of size 150-200 nm are analyzed for their stability, degradation capacity, model drug-release profile, biocompatibility and photothermal effects on cancer cells. It is observed that when these particles are subjected to low power continuous wave near infra-red (NIR) laser for more than 10 min, they degrade into small gold nanoparticles of size 5 nm. Also, the gold coated liposomes appear to have excellent biocompatibility and high efficiency to kill cancer cells through photothermal transduction. These novel materials are also useful in imaging using specific NIR dyes, thus exhibiting multifunctional properties for theranostics of cancer.Plasmon resonant gold nanoparticles of various sizes and shapes have been extensively researched for their applications in imaging, drug delivery and photothermal therapy (PTT). However, their ability to degrade after performing the required function is essential for their application in healthcare. When combined with biodegradable liposomes, they appear to have better degradation capabilities. They degrade into smaller particles of around 5 nm that are eligible candidates for renal clearance. Distearoyl phosphatidyl choline : cholesterol (DSPC : CHOL, 8 : 2 wt%) liposomes have been synthesized and coated with gold by in situ reduction of chloro-auric acid. These

  6. Single-cell nanotoxicity assays of superparamagnetic iron oxide nanoparticles.

    Science.gov (United States)

    Eustaquio, Trisha; Leary, James F

    2012-01-01

    Properly evaluating the nanotoxicity of nanoparticles involves much more than bulk-cell assays of cell death by necrosis. Cells exposed to nanoparticles may undergo repairable oxidative stress and DNA damage or be induced into apoptosis. Exposure to nanoparticles may cause the cells to alter their proliferation or differentiation or their cell-cell signaling with neighboring cells in a tissue. Nanoparticles are usually more toxic to some cell subpopulations than others, and toxicity often varies with cell cycle. All of these facts dictate that any nanotoxicity assay must be at the single-cell level and must try whenever feasible and reasonable to include many of these other factors. Focusing on one type of quantitative measure of nanotoxicity, we describe flow and scanning image cytometry approaches to measuring nanotoxicity at the single-cell level by using a commonly used assay for distinguishing between necrotic and apoptotic causes of cell death by one type of nanoparticle. Flow cytometry is fast and quantitative, provided that the cells can be prepared into a single-cell suspension for analysis. But when cells cannot be put into suspension without altering nanotoxicity results, or if morphology, attachment, and stain location are important, a scanning image cytometry approach must be used. Both methods are described with application to a particular type of nanoparticle, a superparamagnetic iron oxide nanoparticle (SPION), as an example of how these assays may be applied to the more general problem of determining the effects of nanomaterial exposure to living cells.

  7. Potential toxicity of superparamagnetic iron oxide nanoparticles (SPION

    Directory of Open Access Journals (Sweden)

    Neenu Singh

    2010-09-01

    Full Text Available Superparamagnetic iron oxide nanoparticles (SPION are being widely used for various biomedical applications, for example, magnetic resonance imaging, targeted delivery of drugs or genes, and in hyperthermia. Although, the potential benefits of SPION are considerable, there is a distinct need to identify any potential cellular damage associated with these nanoparticles. Besides focussing on cytotoxicity, the most commonly used determinant of toxicity as a result of exposure to SPION, this review also mentions the importance of studying the subtle cellular alterations in the form of DNA damage and oxidative stress. We review current studies and discuss how SPION, with or without different surface coating, may cause cellular perturbations including modulation of actin cytoskeleton, alteration in gene expression profiles, disturbance in iron homeostasis and altered cellular responses such as activation of signalling pathways and impairment of cell cycle regulation. The importance of protein–SPION interaction and various safety considerations relating to SPION exposure are also addressed.

  8. Characterization of magnetic iron oxide nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Lančok, Adriana; Klementová, Mariana; Bezdička, Petr; Miglierini, M.

    2009-01-01

    Roč. 189, 1-3 (2009), s. 97-103 ISSN 0304-3843 R&D Projects: GA ČR GP203/07/P011 Institutional research plan: CEZ:AV0Z40320502 Keywords : nanoparticles * Mössbauer spectroscopy - ε-Fe2O3 phase * epsilon-Fe2O3 phase Subject RIV: CA - Inorganic Chemistry Impact factor: 0.209, year: 2007

  9. CO 2 hydrogenation to hydrocarbons over iron nanoparticles ...

    Indian Academy of Sciences (India)

    Hydrogenation of CO2 to hydrocarbons over iron nanoparticles supported on oxygenfunctionalized multi-walled carbon nanotubes was studied in a fixed-bed U-tube reactor at 25 bar with a H2:CO2 ratio of 3. Conversion of CO2 was approximately 35% yielding C1-C5 products at 360°C with methane and CO as major ...

  10. Super-iron Nanoparticles with Facile Cathodic Charge Transfer

    Energy Technology Data Exchange (ETDEWEB)

    M Farmand; D Jiang; B Wang; S Ghosh; D Ramaker; S Licht

    2011-12-31

    Super-irons contain the + 6 valence state of iron. One advantage of this is that it provides a multiple electron opportunity to store additional battery charge. A decrease of particle size from the micrometer to the nanometer domain provides a higher surface area to volume ratio, and opportunity to facilitate charge transfer, and improve the power, voltage and depth of discharge of cathodes made from such salts. However, super-iron salts are fragile, readily reduced to the ferric state, with both heat and contact with water, and little is known of the resultant passivating and non-passivating ferric oxide products. A pathway to decrease the super-iron particle size to the nano-domain is introduced, which overcomes this fragility, and retains the battery capacity advantage of their Fe(VI) valence state. Time and power controlled mechanosynthesis, through less aggressive, dry ball milling, leads to facile charge transfer of super-iron nanoparticles. Ex-situ X-ray Absorption Spectroscopy is used to explore the oxidation state and structure of these iron oxides during discharge and shows the significant change in stability of the ferrate structure to lower oxidation state when the particle size is in the nano-domain.

  11. Tuning Surface Chemistry of Polyetheretherketone by Gold Coating and Plasma Treatment

    Science.gov (United States)

    Novotná, Zdeňka; Rimpelová, Silvie; Juřík, Petr; Veselý, Martin; Kolská, Zdeňka; Hubáček, Tomáš; Borovec, Jakub; Švorčík, Václav

    2017-06-01

    Polyetheretherketone (PEEK) has good chemical and biomechanical properties that are excellent for biomedical applications. However, PEEK exhibits hydrophobic and other surface characteristics which cause limited cell adhesion. We have investigated the potential of Ar plasma treatment for the formation of a nanostructured PEEK surface in order to enhance cell adhesion. The specific aim of this study was to reveal the effect of the interface of plasma-treated and gold-coated PEEK matrices on adhesion and spreading of mouse embryonic fibroblasts. The surface characteristics (polarity, surface chemistry, and structure) before and after treatment were evaluated by various experimental techniques (gravimetry, goniometry, X-ray photoelectron spectroscopy (XPS), and electrokinetic analysis). Further, atomic force microscopy (AFM) was employed to examine PEEK surface morphology and roughness. The biological response of cells towards nanostructured PEEK was evaluated in terms of cell adhesion, spreading, and proliferation. Detailed cell morphology was evaluated by scanning electron microscopy (SEM). Compared to plasma treatment, gold coating improved PEEK wettability. The XPS method showed a decrease in the carbon concentration with increasing time of plasma treatment. Cell adhesion determined on the interface between plasma-treated and gold-coated PEEK matrices was directly proportional to the thickness of a gold layer on a sample. Our results suggest that plasma treatment in a combination with gold coating could be used in biomedical applications requiring enhanced cell adhesion.

  12. Tuning Surface Chemistry of Polyetheretherketone by Gold Coating and Plasma Treatment.

    Science.gov (United States)

    Novotná, Zdeňka; Rimpelová, Silvie; Juřík, Petr; Veselý, Martin; Kolská, Zdeňka; Hubáček, Tomáš; Borovec, Jakub; Švorčík, Václav

    2017-12-01

    Polyetheretherketone (PEEK) has good chemical and biomechanical properties that are excellent for biomedical applications. However, PEEK exhibits hydrophobic and other surface characteristics which cause limited cell adhesion. We have investigated the potential of Ar plasma treatment for the formation of a nanostructured PEEK surface in order to enhance cell adhesion. The specific aim of this study was to reveal the effect of the interface of plasma-treated and gold-coated PEEK matrices on adhesion and spreading of mouse embryonic fibroblasts. The surface characteristics (polarity, surface chemistry, and structure) before and after treatment were evaluated by various experimental techniques (gravimetry, goniometry, X-ray photoelectron spectroscopy (XPS), and electrokinetic analysis). Further, atomic force microscopy (AFM) was employed to examine PEEK surface morphology and roughness. The biological response of cells towards nanostructured PEEK was evaluated in terms of cell adhesion, spreading, and proliferation. Detailed cell morphology was evaluated by scanning electron microscopy (SEM). Compared to plasma treatment, gold coating improved PEEK wettability. The XPS method showed a decrease in the carbon concentration with increasing time of plasma treatment. Cell adhesion determined on the interface between plasma-treated and gold-coated PEEK matrices was directly proportional to the thickness of a gold layer on a sample. Our results suggest that plasma treatment in a combination with gold coating could be used in biomedical applications requiring enhanced cell adhesion.

  13. Ca alginate as scaffold for iron oxide nanoparticles synthesis

    Directory of Open Access Journals (Sweden)

    P. V. Finotelli

    2008-12-01

    Full Text Available Recently, nanotechnology has developed to a stage that makes it possible to process magnetic nanoparticles for the site-specific delivery of drugs. To this end, it has been proposed as biomaterial for drug delivery system in which the drug release rates would be activated by a magnetic external stimuli. Alginate has been used extensively in the food, pharmaceutical and biomedical industries for their gel forming properties in the presence of multivalent cations. In this study, we produced iron oxide nanoparticles by coprecipitation of Fe(III and Fe(II. The nanoparticles were entrapped in Ca alginate beads before and after alginate gelation. XRD analysis showed that particles should be associated to magnetite or maghemite with crystal size of 9.5 and 4.3 nm, respectively. Studies using Mössbauer spectroscopy corroborate the superparamagnetic behavior. The combination of magnetic properties and the biocompatibility of alginate suggest that this biomaterial may be used as biomimetic system.

  14. Solid lipid nanoparticles loaded with iron to overcome barriers for treatment of iron deficiency anemia

    Directory of Open Access Journals (Sweden)

    Hosny KM

    2015-01-01

    Full Text Available Khaled Mohamed Hosny,1,2 Zainy Mohammed Banjar,3 Amani H Hariri,4 Ali Habiballah Hassan5 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Beni Suef University, Beni Suef, Egypt; 3Department of Clinical Biochemistry, Faculty of medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 4Consultant Obstetrics and Gynecology, Hera Genaral Hospital, Makkah, Saudi Arabia; 5Department of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia Abstract: According to the World Health Organization, 46% of the world’s children suffer from anemia, which is usually treated with iron supplements such as ferrous sulfate. The aim of this study was to prepare iron as solid lipid nanoparticles, in order to find an innovative way for alleviating the disadvantages associated with commercially available tablets. These limitations include adverse effects on the digestive system resulting in constipation and blood in the stool. The second drawback is the high variability in the absorption of iron and thus in its bioavailability. Iron solid lipid nanoparticles (Fe-SLNs were prepared by hot homogenization/ultrasonication. Solubility of ferrous sulfate in different solid lipids was measured, and effects of process variables such as the surfactant type and concentration, homogenization and ultrasonication times, and charge-inducing agent on the particle size, zeta potential, and encapsulation efficiency were determined. Furthermore, in vitro drug release and in vivo pharmacokinetics were studied in rabbits. Results indicated that Fe-SLNs consisted of 3% Compritol 888 ATO, 1% Lecithin, 3% Poloxamer 188, and 0.2% dicetylphosphate, with an average particle size of 25 nm with 92.3% entrapment efficiency. In vivo pharmacokinetic study revealed more than fourfold enhanced bioavailability. In

  15. Superparamagnetic iron oxide nanoparticles: magnetic nanoplatforms as drug carriers

    Directory of Open Access Journals (Sweden)

    Wahajuddin

    2012-07-01

    Full Text Available Wahajuddin,1,2 Sumit Arora21Pharmacokinetics and Metabolism Division, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, 2Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research, Rae Bareli, IndiaAbstract: A targeted drug delivery system is the need of the hour. Guiding magnetic iron oxide nanoparticles with the help of an external magnetic field to its target is the principle behind the development of superparamagnetic iron oxide nanoparticles (SPIONs as novel drug delivery vehicles. SPIONs are small synthetic γ-Fe2O3 (maghemite or Fe3O4 (magnetite particles with a core ranging between 10 nm and 100 nm in diameter. These magnetic particles are coated with certain biocompatible polymers, such as dextran or polyethylene glycol, which provide chemical handles for the conjugation of therapeutic agents and also improve their blood distribution profile. The current research on SPIONs is opening up wide horizons for their use as diagnostic agents in magnetic resonance imaging as well as for drug delivery vehicles. Delivery of anticancer drugs by coupling with functionalized SPIONs to their targeted site is one of the most pursued areas of research in the development of cancer treatment strategies. SPIONs have also demonstrated their efficiency as nonviral gene vectors that facilitate the introduction of plasmids into the nucleus at rates multifold those of routinely available standard technologies. SPION-induced hyperthermia has also been utilized for localized killing of cancerous cells. Despite their potential biomedical application, alteration in gene expression profiles, disturbance in iron homeostasis, oxidative stress, and altered cellular responses are some SPION-related toxicological aspects which require due consideration. This review provides a comprehensive understanding of SPIONs with regard to their method of preparation, their utility as drug delivery vehicles, and some concerns which need to

  16. Stabilization and functionalization of iron oxide nanoparticles for biomedical applications

    Science.gov (United States)

    Amstad, Esther; Textor, Marcus; Reimhult, Erik

    2011-07-01

    Superparamagnetic iron oxide nanoparticles (NPs) are used in a rapidly expanding number of research and practical applications in the biomedical field, including magnetic cell labeling separation and tracking, for therapeutic purposes in hyperthermia and drug delivery, and for diagnostic purposes, e.g., as contrast agents for magnetic resonance imaging. These applications require good NP stability at physiological conditions, close control over NP size and controlled surface presentation of functionalities. This review is focused on different aspects of the stability of superparamagnetic iron oxide NPs, from its practical definition to its implementation by molecular design of the dispersant shell around the iron oxide core and further on to its influence on the magnetic properties of the superparamagnetic iron oxide NPs. Special attention is given to the selection of molecular anchors for the dispersant shell, because of their importance to ensure colloidal and functional stability of sterically stabilized superparamagnetic iron oxide NPs. We further detail how dispersants have been optimized to gain close control over iron oxide NP stability, size and functionalities by independently considering the influences of anchors and the attached sterically repulsive polymer brushes. A critical evaluation of different strategies to stabilize and functionalize core-shell superparamagnetic iron oxide NPs as well as a brief introduction to characterization methods to compare those strategies is given.Superparamagnetic iron oxide nanoparticles (NPs) are used in a rapidly expanding number of research and practical applications in the biomedical field, including magnetic cell labeling separation and tracking, for therapeutic purposes in hyperthermia and drug delivery, and for diagnostic purposes, e.g., as contrast agents for magnetic resonance imaging. These applications require good NP stability at physiological conditions, close control over NP size and controlled surface

  17. Iron oxide nanoparticles for magnetically assisted patterned coatings

    Energy Technology Data Exchange (ETDEWEB)

    Dodi, Gianina; Hritcu, Doina, E-mail: dhritcu@ch.tuiasi.ro; Draganescu, Dan; Popa, Marcel I.

    2015-08-15

    Iron oxide nanoparticles able to magnetically assemble during the curing stage of a polymeric support to create micro-scale surface protuberances in a controlled manner were prepared and characterized. The bare Fe{sub 3}O{sub 4} particles were obtained by two methods: co-precipitation from an aqueous solution containing Fe{sup 3+}/Fe{sup 2+} ions with a molar ratio of 2:1 and partial oxidation of ferrous ions in alkaline conditions. The products were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and magnetization measurement. They were subsequently functionalized using oleic acid, sodium oleate, or non-ionic surfactant mixtures with various hydrophilic to lipophilic balance (HLB) values. Composite nanoparticle-polymer films prepared by spraying were deposited and cured by drying on glass slides under a static magnetic field in the range of 1.5–5.5 mT. Magnetic field generated surface roughness was evidenced by optical and scanning electron microscopy. The optimum hierarchical patterning was obtained with the nanoparticles produced by partial oxidation and functionalized with hydrophobic surfactants. Possible applications may include ice-phobic composite coatings. - Highlights: • Magnetite nanoparticles bearing variable hydrophobic functionality were synthesized. • Partial oxidation in alkaline solution is proved to be the optimum synthesis method. • Nanoparticle assembly in magnetic field produced films with hierarchical roughness. • Coating patterning is controlled by surfactant nature and magnetic field strength. • Possible applications in composite films with ice-phobic properties are suggested.

  18. Mechanism of the reduction of hexavalent chromium by organo-montmorillonite supported iron nanoparticles

    International Nuclear Information System (INIS)

    Wu, Pingxiao; Li, Shuzhen; Ju, Liting; Zhu, Nengwu; Wu, Jinhua; Li, Ping; Dang, Zhi

    2012-01-01

    Highlights: ► Organo-montmorillonite supported iron nanoparticles were found to be more efficient in the removal of Cr(VI) than unsupported iron nanoparticles. ► The iron nanoparticles were accommodated by the sectional structure of the clay minerals which were helpful to protect the nanoparticles from aggregating. ► XPS and XANES provided some direct information about the reduction mechanisms. ► The structure of the supported iron nanoparticles was stable in the reaction with Cr(VI). - Abstract: Iron nanoparticles exhibit greater reactivity than micro-sized Fe 0 , and they impart advantages for groundwater remediation. In this paper, supported iron nanoparticles were synthesized to further enhance the speed and efficiency of remediation. Natural montmorillonite and organo-montmorillonite were chosen as supporting materials. The capacity of supported iron nanoparticles was evaluated, compared to unsupported iron nanoparticles, for the reduction of aqueous Cr(VI). The reduction of Cr(VI) was much greater with organo-montmorillonite supported iron nanoparticles and fitted the pseudo-second order equation better. With a dose at 0.47 g/L, a total removal capacity of 106 mg Cr/g Fe 0 was obtained. Other factors that affect the efficiency of Cr(VI) removal, such as pH values, the initial Cr(VI) concentration and storage time of nanoparticles were investigated. X-ray photoelectron spectrometry (XPS) and X-ray absorption near edge structure (XANES) were used to figure out the mechanism of the removal of Cr(VI). XPS indicated that the Cr(VI) bound to the particle surface was completely reduced to Cr(III) under a range of conditions. XANES confirmed that the Cr(VI) reacted with iron nanoparticles was completely reduced to Cr(III).

  19. Synthesis and Characterization of Holmium-Doped Iron Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Maarten Bloemen

    2014-02-01

    Full Text Available Rare earth atoms exhibit several interesting properties, for example, large magnetic moments and luminescence. Introducing these atoms into a different matrix can lead to a material that shows multiple interesting effects. Holmium atoms were incorporated into an iron oxide nanoparticle and the concentration of the dopant atom was changed in order to determine its influence on the host crystal. Its magnetic and magneto-optical properties were investigated by vibrating sample magnetometry and Faraday rotation measurements. The luminescent characteristics of the material, in solution and incorporated in a polymer thin film, were probed by fluorescence experiments.

  20. Iron oxide nanoparticles for plant nutrition? A preliminary Mössbauer study

    Energy Technology Data Exchange (ETDEWEB)

    Homonnay, Z., E-mail: homonnay@caesar.elte.hu [EötvösLoránd University, Institute of Chemistry (Hungary); Tolnai, Gy. [Research Centre for Natural Sciences, Institute of Materials and Environmental Chemistry (Hungary); Fodor, F.; Solti, Á. [EötvösLoránd University, Institute of Biology (Hungary); Kovács, K.; Kuzmann, E.; Ábrahám, A. [EötvösLoránd University, Institute of Chemistry (Hungary); Szabó, E. Gy.; Németh, P.; Szabó, L.; Klencsár, Z. [Research Centre for Natural Sciences, Institute of Materials and Environmental Chemistry (Hungary)

    2016-12-15

    One of the most important micronutrients for plants is iron. We have prepared iron(III) oxyhydroxide and magnetite nanoparticles with the aim to use them as possible nutrition source for plants. The iron(III)-oxide/oxyhydroxide nanoparticles prepared under our experimental conditions as colloidal suspensions proved to be 6-line ferrihydrite nanoparticles as verified by XRD, TEM/SAED and Mössbauer spectroscopy measurements. {sup 57}Fe Mössbauer spectra of magnetite nanoparticles prepared under different preparation conditions could be analyzed on the basis of a common model based on the superposition of four sextet components displaying Gaussian-shaped hyperfine magnetic field distributions.

  1. Chromium Elimination from Water by use of Iron Oxide Nanoparticles Absorbents

    Directory of Open Access Journals (Sweden)

    S Shokraei

    2014-09-01

    Results: results showed that best absorbent is soil absorbent and iron oxide nanoparticles, with maximum removal percent equal to 96.2%. Also best turnover was obtained from 8837 ppm of primary concentration of heavy metal. In other hand, in other experiments that used from iron oxide nanoparticles, adding of nanoparticles caused to increase in chrome absorption and conversion of Cr6+ to Cr3+. Conclusion: with use of the results of this study can be said that Combining of iron oxide nanoparticles with chrome removal filters can be convert Cr6+ to Cr3+, and process turnover will increased.

  2. Iron oxide nanoparticles for plant nutrition? A preliminary Mössbauer study

    Science.gov (United States)

    Homonnay, Z.; Tolnai, Gy.; Fodor, F.; Solti, Á.; Kovács, K.; Kuzmann, E.; Ábrahám, A.; Szabó, E. Gy.; Németh, P.; Szabó, L.; Klencsár, Z.

    2016-12-01

    One of the most important micronutrients for plants is iron. We have prepared iron(III) oxyhydroxide and magnetite nanoparticles with the aim to use them as possible nutrition source for plants. The iron(III)-oxide/oxyhydroxide nanoparticles prepared under our experimental conditions as colloidal suspensions proved to be 6-line ferrihydrite nanoparticles as verified by XRD, TEM/SAED and Mössbauer spectroscopy measurements. 57Fe Mössbauer spectra of magnetite nanoparticles prepared under different preparation conditions could be analyzed on the basis of a common model based on the superposition of four sextet components displaying Gaussian-shaped hyperfine magnetic field distributions.

  3. Biosynthesis of Iron Nanoparticles Using Tie Guanyin Tea Extract for Degradation of Bromothymol Blue

    Directory of Open Access Journals (Sweden)

    Haiyan Xin

    2016-01-01

    Full Text Available Facile synthesis of zero-valent iron nanoparticles has been developed using Tie Guanyin tea extract as reducing and stabilizing agent. The characterization carried out by UV-Vis, SEM, TEM, XRD, and FTIR techniques has identified the successful synthesis of the zero-valent iron nanoparticles. It is evident from the TEM result that spherical zero-valent iron nanoparticles with average size of 6.58±0.76 nm have been obtained through biological method in this study. FTIR spectrum demonstrates that the polyphenols play an important role in the synthetic process. Diffraction peak at 2θ of 44.9° and 49.1° in XRD spectrum explains the existence of the iron nanoparticles. Additionally, effect of concentration of iron nanoparticles and concentration of bromothymol blue on the kinetic rate constants during the degradation process was studied.

  4. Optimization study of direct morphology observation by cold field emission SEM without gold coating.

    Science.gov (United States)

    He, Dan; Fu, Cheng; Xue, Zhigang

    2018-04-06

    Gold coating is a general operation that is generally applied on non-conductive or low conductive materials, during which the morphology of the materials can be examined by scanning electron microscopy (SEM). However, fatal deficiencies in the materials can result in irreversible distortion and damage. The present study directly characterized different low conductive materials such as hydroxyapatite, modified poly(vinylidene fluoride) (PVDF) fiber, and zinc oxide nanopillar by cold field emission scanning electron microscopy (FE-SEM) without a gold coating. According to the characteristics of the low conductive materials, various test conditions, such as different working signal modes, accelerating voltages, electron beam spots, and working distances, were characterized to determine the best morphological observations of each sample. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Shape control of the magnetic iron oxide nanoparticles under different chain length of reducing agents

    Energy Technology Data Exchange (ETDEWEB)

    Ngoi, Kuan Hoon; Chia, Chin-Hua, E-mail: chia@ukm.edu.my; Zakaria, Sarani [School of Applied Physics, Faculty Science and Technology, University Kebangsaan Malaysia 43600 UKM Bangi, Selangor (Malaysia); Chiu, Wee Siong [Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Lembah Pantai, Kuala Lumpur (Malaysia)

    2015-09-25

    We report on the effect of using reducing agents with different chain-length on the synthesis of iron oxide nanoparticles by thermal decomposition of iron (III) acetylacetonate in 1-octadecene. This modification allows us to control the shape of nanoparticles into spherical and cubic iron oxide nanoparticles. The highly monodisperse 14 nm spherical nanoparticles are obtained under 1,2-dodecanediol and average 14 nm edge-length cubic iron oxide nanoparticles are obtained under 1,2-tetradecanediol. The structural characterization such as transmission electron microscope (TEM) and X-ray diffraction (XRD) shows similar properties between two particles with different shapes. The vibrating sample magnetometer (VSM) shows no significant difference between spherical and cubic nanoparticles, which are 36 emu/g and 37 emu/g respectively and superparamagnetic in nature.

  6. Green Synthesis of Iron Nanoparticles and Their Environmental Applications and Implications

    Directory of Open Access Journals (Sweden)

    Sadia Saif

    2016-11-01

    Full Text Available Recent advances in nanoscience and nanotechnology have also led to the development of novel nanomaterials, which ultimately increase potential health and environmental hazards. Interest in developing environmentally benign procedures for the synthesis of metallic nanoparticles has been increased. The purpose is to minimize the negative impacts of synthetic procedures, their accompanying chemicals and derivative compounds. The exploitation of different biomaterials for the synthesis of nanoparticles is considered a valuable approach in green nanotechnology. Biological resources such as bacteria, algae fungi and plants have been used for the production of low-cost, energy-efficient, and nontoxic environmental friendly metallic nanoparticles. This review provides an overview of various reports of green synthesised zero valent metallic iron (ZVMI and iron oxide (Fe2O3/Fe3O4 nanoparticles (NPs and highlights their substantial applications in environmental pollution control. This review also summarizes the ecotoxicological impacts of green synthesised iron nanoparticles opposed to non-green synthesised iron nanoparticles.

  7. Green Synthesis of Iron Nanoparticles and Their Environmental Applications and Implications

    Science.gov (United States)

    Saif, Sadia; Tahir, Arifa; Chen, Yongsheng

    2016-01-01

    Recent advances in nanoscience and nanotechnology have also led to the development of novel nanomaterials, which ultimately increase potential health and environmental hazards. Interest in developing environmentally benign procedures for the synthesis of metallic nanoparticles has been increased. The purpose is to minimize the negative impacts of synthetic procedures, their accompanying chemicals and derivative compounds. The exploitation of different biomaterials for the synthesis of nanoparticles is considered a valuable approach in green nanotechnology. Biological resources such as bacteria, algae fungi and plants have been used for the production of low-cost, energy-efficient, and nontoxic environmental friendly metallic nanoparticles. This review provides an overview of various reports of green synthesised zero valent metallic iron (ZVMI) and iron oxide (Fe2O3/Fe3O4) nanoparticles (NPs) and highlights their substantial applications in environmental pollution control. This review also summarizes the ecotoxicological impacts of green synthesised iron nanoparticles opposed to non-green synthesised iron nanoparticles. PMID:28335338

  8. Fabrication of black-gold coatings by glancing angle deposition with sputtering

    Directory of Open Access Journals (Sweden)

    Alan Vitrey

    2017-02-01

    Full Text Available The fabrication of black-gold coatings using sputtering is reported here. Glancing angle deposition with a rotating substrate is needed to obtain vertical nanostructures. Enhanced light absorption is obtained in the samples prepared in the ballistic regime with high tilt angles. Under these conditions the diameter distribution of the nanostructures is centered at about 60 nm and the standard deviation is large enough to obtain black-metal behavior in the visible range.

  9. Coupling Graphene Sheets with Iron Oxide Nanoparticles for Energy Storage and Microelectronics

    Science.gov (United States)

    2015-12-18

    AFRL-AFOSR-JP-TR-2016-0002 Coupling Graphene Sheets with Iron Oxide Nanoparticles for Energy Storage and Microelectronics Kwang-Sup Lee HANNAM...SUBTITLE Coupling Graphene Sheets with Iron Oxide Nanoparticles for Energy Storage and Microelectronics 5a. CONTRACT NUMBER FA2386-12-1-4010...superparamagnetic γ-Fe2O3 magnetic nanoparticles (MNP) to grapheme-based materials. The distance of the ligands to the graphene derivative surface can be

  10. Multidomain iron nanoparticles for the preparation of polyacrylamide ferrogels

    Energy Technology Data Exchange (ETDEWEB)

    Shankar, Ajay, E-mail: ashankar@urfu.ru [Ural Federal University, 19 Mira Str., 620002 Yekaterinburg (Russian Federation); Safronov, Alexander P. [Ural Federal University, 19 Mira Str., 620002 Yekaterinburg (Russian Federation); Institute of Electrophysics UB RAS, 106 Amundsen Str., 620016 Yekaterinburg (Russian Federation); Mikhnevich, Ekaterina A. [Ural Federal University, 19 Mira Str., 620002 Yekaterinburg (Russian Federation); Beketov, Igor V. [Ural Federal University, 19 Mira Str., 620002 Yekaterinburg (Russian Federation); Institute of Electrophysics UB RAS, 106 Amundsen Str., 620016 Yekaterinburg (Russian Federation)

    2017-06-01

    Ferrogels (FG) based on poly(acrylamide) (PAAm) with embedded multidomain iron magnetic nanoparticles (MNPs) were synthesized by radical polymerization in water. Iron MNPs prepared by the electrical explosion of wire were spherical in shape and have an average diameter around 100 nm. MNPs were modified by a surfactant – oleic acid to improve their dispersion in water. DLVO theoretical consideration was done to understand the stability of dispersions. By microcalorimetry it was shown that the oleic layer on the surface of MNPs prevents their interaction with PAAm network of FG. Mechanical testing of the compression modulus and the deformation of FGs in magnetic field show up their prospectiveness as a material for magnetically sensitive MEMS and actuators. - Highlights: • Ferrogels were synthesized by radical polymerization in water. • DLVO theoretical consideration was done to understand the stability of dispersions. • Surfactant blocks the interfacial interaction of PAAm chains with particles. • Ferrogels show magnetodeformation when placed in magnetic field. • Grinding approach can also be used for other nanoparticles viz., Ni, Al, Al{sub 2}O{sub 3} etc.

  11. Crystallization process and magnetic properties of amorphous iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Phu, N D; Luong, N H; Chau, N; Hai, N H; Ngo, D T; Hoang, L H

    2011-01-01

    This paper studied the crystallization process, phase transition and magnetic properties of amorphous iron oxide nanoparticles prepared by the microwave heating technique. Thermal analysis and magnetodynamics studies revealed many interesting aspects of the amorphous iron oxide nanoparticles. The as-prepared sample was amorphous. Crystallization of the maghemite γ-Fe 2 O 3 (with an activation energy of 0.71 eV) and the hematite α-Fe 2 O 3 (with an activation energy of 0.97 eV) phase occurred at around 300 deg. C and 350 deg. C, respectively. A transition from the maghemite to the hematite occurred at 500 deg. C with an activation energy of 1.32 eV. A study of the temperature dependence of magnetization supported the crystallization and the phase transformation. Raman shift at 660 cm -1 and absorption band in the infrared spectra at 690 cm -1 showed the presence of disorder in the hematite phase on the nanoscale which is supposed to be the origin of the ferromagnetic behaviour of that antiferromagnetic phase.

  12. In vitro cytotoxicity of iron oxide nanoparticles: effects of chitosan and polyvinyl alcohol as stabilizing agents

    Science.gov (United States)

    Tran, Phong A.; Nguyen, Hiep T.; Fox, Kate; Tran, Nhiem

    2018-03-01

    Iron oxide magnetic nanoparticles have significant potential in biomedical applications such as in diagnosis, imaging and therapeutic agent delivery. The choice of stabilizers and surface functionalization is important as it is known to strongly influence the cytotoxicity of the nanoparticles. The present study aimed at investigating the effects of surface charges on the cytotoxicity of iron oxide nanoparticles. We used a co-precipitation method to synthesize iron oxide nanoparticles which were then stabilized with either chitosan (CS) or polyvinyl alcohol (PVA) which have net positive charge and zero charge at physiological pH, respectively. The nanoparticles were characterized in terms of size, charges and chemical oxidation state. Cytotoxicity of the nanoparticles was assessed using mouse fibroblast cells and was correlated with surface charges of the nanoparticles and their aggregation.

  13. Synthesis and characterization of diblock copolymer templated iron oxide nanoparticles

    Science.gov (United States)

    Akcora, Pinar

    2005-07-01

    Templating ordered assemblies of magnetic oxide nanoparticles within self-assembled diblock copolymers of varying morphologies is an important problem with a wide applicability such as in electromagnetics, optical devices, metal catalysts, medicine and biology. In this thesis, the effects of different polymer structures on particle ordering and resultant magnetic properties have been investigated using various microstructure and magnetic characterization tools. Ring-opening metathesis polymerization (ROMP) of norbornene and functionalized norbornene monomers has been used to synthesize diblock copolymers of narrow polydispersities using Grubbs' catalyst. These block copolymers can be used as templates to form inorganic nanoparticles. In this research, the structural and physical understanding of the inorganic-copolymer system was studied by small-angle neutron and x-ray scattering techniques and transmission electron microscopy. Synthesis of gamma-Fe2O3 nanoparticles has been achieved within novel block copolymers of (norbornene)-b-(deuterated norbornene dicarboxylic) acid and (norbornene methanol-(norbornene dicarboxylic acid). The polymer morphologies were controlled by varying the volume fractions of the constituent blocks. The pure norbornene based diblock copolymer morphologies were demonstrated by electron microscopy for the first tune. Spherical, cylindrical and lamellar morphologies of these novel diblock copolymers were reported. The block ratios of the synthesized polymers were determined using gel permeation chromatography-light scattering, elemental analysis and UV-VIS spectroscopy. Solution phase doping and submersion of thin films in metal salt solutions were employed as metal doping methods and the observed nanoparticle structures were compared to those of the undoped copolymer morphologies. This project reports on the types of templating structures and dispersion of the nanoparticles. The effects of particle, interactions on the microphase

  14. Physiological effects of magnetic iron oxide nanoparticles towards watermelon.

    Science.gov (United States)

    Li, Junli; Chang, Peter R; Huang, Jin; Wang, Yunqiang; Yuan, Hong; Ren, Hongxuan

    2013-08-01

    Nanoparticles (NPs) have been exploited in a diverse range of products in the past decade or so. However, the biosafety/environmental impact or legislation pertaining to this newly created, highly functional composites containing NPs (otherwise called nanomaterials) is generally lagging behind their technological innovation. To advance the agenda in this area, our current primary interest is focused on using crops as model systems as they have very close relationship with us. Thus, the objective of the present study was to evaluate the biological effects of magnetic iron oxide nanoparticles towards watermelon seedlings. We have systematically studied the physiological effects of Fe2O3 nanoparticles (nano-Fe2O3) on watermelon, and present the first evidence that a significant amount of Fe2O3 nanoparticles suspended in a liquid medium can be taken up by watermelon plants and translocated throughout the plant tissues. Changes in important physiological indicators, such as root activity, activity of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), chlorophyll and malondialdehyde (MDA) contents, ferric reductase activity, root apoplastic iron content were clearly presented. Different concentrations of nano-Fe2O3 all increased seed germination, seedling growth, and enhanced physiological function to some degree; and the positive effects increased quickly and then slowed with an increase in the treatment concentrations. Changes in CAT, SOD and POD activities due to nano-Fe2O3 were significantly larger than that of the control. The 20 mg/L treatment had the most obvious effect on the increase of root activity. Ferric reductase activity, root apoplastic iron content, and watermelon biomass were significantly affected by exposure to nano-Fe2O3. Results of statistical analysis showed that there were significant differences in all the above indexes between the treatment at optimal concentration and the control. This proved that the proper concentration of nano

  15. Physical characterization and in vivo organ distribution of coated iron oxide nanoparticles.

    Science.gov (United States)

    Sharma, Anirudh; Cornejo, Christine; Mihalic, Jana; Geyh, Alison; Bordelon, David E; Korangath, Preethi; Westphal, Fritz; Gruettner, Cordula; Ivkov, Robert

    2018-03-20

    Citrate-stabilized iron oxide magnetic nanoparticles (MNPs) were coated with one of carboxymethyl dextran (CM-dextran), polyethylene glycol-polyethylene imine (PEG-PEI), methoxy-PEG-phosphate+rutin, or dextran. They were characterized for size, zeta potential, hysteresis heating in an alternating magnetic field, dynamic magnetic susceptibility, and examined for their distribution in mouse organs following intravenous delivery. Except for PEG-PEI-coated nanoparticles, all coated nanoparticles had a negative zeta potential at physiological pH. Nanoparticle sizing by dynamic light scattering revealed an increased nanoparticle hydrodynamic diameter upon coating. Magnetic hysteresis heating changed little with coating; however, the larger particles demonstrated significant shifts of the peak of complex magnetic susceptibility to lower frequency. 48 hours following intravenous injection of nanoparticles, mice were sacrificed and tissues were collected to measure iron concentration. Iron deposition from nanoparticles possessing a negative surface potential was observed to have highest accumulation in livers and spleens. In contrast, iron deposition from positively charged PEG-PEI-coated nanoparticles was observed to have highest concentration in lungs. These preliminary results suggest a complex interplay between nanoparticle size and charge determines organ distribution of systemically-delivered iron oxide magnetic nanoparticles.

  16. Macroscopic and microscopic biodistribution of intravenously administered iron oxide nanoparticles

    Science.gov (United States)

    Misra, Adwiteeya; Petryk, Alicia A.; Strawbridge, Rendall R.; Hoopes, P. Jack

    2015-03-01

    Iron oxide nanoparticles (IONP) are being developed for use as a cancer treatment. They have demonstrated efficacy when used either as a monotherapy or in conjunction with conventional chemotherapy and radiation. The success of IONP as a therapeutic tool depends on the delivery of a safe and controlled cytotoxic thermal dose to tumor tissue following activation with an alternating magnetic field (AMF). Prior to clinical approval, knowledge of IONP toxicity, biodistribution and physiological clearance is essential. This preliminary time-course study determines the acute toxicity and biodistribution of 110 nm dextran-coated IONP (iron) in mice, 7 days post systemic, at doses of 0.4, 0.6, and 1.0 mg Fe/ g mouse bodyweight. Acute toxicity, manifested as changes in the behavior of mice, was only observed temporarily at 1.0 mg Fe/ g mouse bodyweight, the highest dose administered. Regardless of dose, mass spectrometry and histological analysis demonstrated over 3 mg Fe/g tissue in organs within the reticuloendotheilial system (i.e. liver, spleen, and lymph nodes). Other organs (brain, heart, lungs, and kidney) had less than 0.5 mg Fe/g tissue with iron predominantly confined to the organ vasculature.

  17. Morphology and phase control of iron oxide polymorph nanoparticles

    Science.gov (United States)

    Cui, Hongtao; Wang, Li; Shi, Min; Li, Yanhong

    2017-04-01

    In this work, lepidocrocite (γ-FeOOH) nanobundles were prepared by a facile NH4F assisted epoxide precipitation route. The reactions between epoxide and [Fe(H2O)6]2+ promoted the hydrolysis and condensation of [Fe(H2O)6]2+, resulting in the formation of iron oxyhydroxide. After calcination of γ-FeOOH nanobundles at 400 °C, the produced α-Fe2O3 still kept the bundle morphology. Due to the unique chemistry of epoxide, the morphology and phase of iron oxide polymorph nanoparticles (goethite, akaganeite, lepidocrocite, magnetite) were well-controlled through controlling reaction conditions such as Fe2+ concentration, NH4F additive and reaction temperature. It is particularly interesting that NH4F working as phase controlling agent is able to control the phase development of iron oxyhydroxides. This phase control effect of NH4F is attributed to the promoted reaction rate of epoxide originating from the higher electronegativity of fluoride ions than chloride ions. Based on the results in this work and our other preliminary works, it is considered that this route can be used as a general strategy for controlling the morphology and phase of transition element compounds.

  18. Iron oxide magnetic nanoparticles as antimicrobials for therapeutics.

    Science.gov (United States)

    de Toledo, Lucas de Alcântara Sica; Rosseto, Hélen Cássia; Bruschi, Marcos Luciano

    2018-04-01

    The use of iron oxide magnetic nanoparticles (IMNP) in medical and pharmaceutical areas dates to the beginning of the 1970s, as carriers. Some other uses to these nanoparticles are in vitro separation, magnetic resonance imaging and drug targeting agent. Many preparations containing IMNP have been described and used in drug delivery, hyperthermia, in vitro separation, tissue repair, cellular therapy, for magnetic separation, magnetic resonance imaging, as spoilers for magnetic resonance spectroscopy, and more recently as sensors for metabolites and other biomolecules. The use of these nanostructures as antibacterial agents has also been reported, which could kill some bacteria species causing no damage to the human host cells. Recently, they have been used as hyperthermia agents to treat infections or cancer, which are more susceptible than the healthy host's cells. Engineering designs, physiochemical characteristics, biomedical applications of IMNP, toxicity and magnetic nanotoxicology have been discussed. However, the application of IMNP as antimicrobials is very important. Thus, this review explores the therapeutic activities of IMNP and their use as antimicrobial agents. These nanoparticles can be efficient for the treatment of microbial infections, probably acting as membrane permeability enhancer, damaging the cell wall or by generating reactive oxygen species.

  19. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    Science.gov (United States)

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

    2015-05-01

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

  20. Phytosynthesis of Iron Nanoparticle from Averrhoa Bilimbi Linn.

    Science.gov (United States)

    Rosli, I. R.; Zulhaimi, H. I.; Ibrahim, S. K. M.; Gopinath, S. C. B.; Kasim, K. F.; Akmal, H. M.; Nuradibah, M. A.; Sam, T. S.

    2018-03-01

    This paper demonstrates iron nanoparticles (FeNP) was synthesized from natural sources of Averrhoa bilimbi Linn. The plant extracts act as natural reducing agent in producing FeNP. There is no addition of any surfactants during the nanoparticles formation. Gravimetric analysis is used to calculate the percentage yield of plant extracts. TPC and DPPH assay method were used to evaluate antioxidant activity in different A. bilimbi extracts and synthesized FeNP. Based on the analyses, it showed that fruit has the highest percentage yield and antioxidant activity followed by leaf, twig and bark. Analysis from TPC, fruit contains 27.26 mg GAE/g and 39.46 mg GAE/g for FeNP. DPPH assay showed fruit extract has the highest free radical antioxidant activity with 61.93% in A. bilimbi and 80.00% in FeNP. Phytosynthesis of FeNP were examine by using UV-Vis spectrophotometer. Based on the spectra, it showed that FeNP recorded peak absorbance at 465 nm, 450 nm, 460 nm and 440 nm for UAE-F, UAE-L, UAE-T and UAE-B, respectively. FTIR analysis shows the presence of strong alcoholic bond, aldehyde, stretch amine and alkene that was responsible in reduction process to form FeNP. The result of UV-Vis and FTIR showed that the existance of FeNP and involvement of functional group that were responsible on the formation of nanoparticles.

  1. Colloidosome-based synthesis of a multifunctional nanostructure of silver and hollow iron oxide nanoparticles

    KAUST Repository

    Pan, Yue

    2010-03-16

    Nanoparticles that self-assemble on a liquid-liquid interface serve as the building block for making heterodimeric nanostructures. Specifically, hollow iron oxide nanoparticles within hexane form colloidosomes in the aqueous solution of silver nitrate, and iron oxide exposed to the aqueous phase catalyzes the reduction of silver ions to afford a heterodimer of silver and hollow iron oxide nanoparticles. Transmission electron microscopy, selected area electron diffraction, energy-dispersive X-ray spectrometry, X-ray diffraction, UV-vis spectroscopy, and SQUID were used to characterize the heterodimers. Interestingly, the formation of silver nanoparticles helps the removal of spinglass layer on the hollow iron oxide nanoparticles. This work demonstrates a powerful yet convenient strategy for producing sophisticated, multifunctional nanostructures. © 2010 American Chemical Society.

  2. Cytotoxic Effect of Iron Oxide Nanoparticles on Mouse Embryonic Stem Cells by MTT Assay

    Directory of Open Access Journals (Sweden)

    Homa Mohseni Kouchesfehani

    2016-07-01

    Full Text Available Background: Despite the wide range of applications, there is a serious lack of information on the impact of the nanoparticles on human health and the environment. The present study was done to determine the range of dangerous concentrations of iron oxide nanoparticle and their effects on mouse embryonic stem cells. Methods: Iron oxide nanoparticles with less than 20 nanometers diameter were encapsulated by a PEG-phospholipid. The suspension of iron oxide nanoparticles was prepared using the culture media and cell viability was determined by MTT assay. Results: MTT assay was used to examine the cytotoxicity of iron oxide nanoparticle s. Royan B1 cells were treated with medium containing different concentrations (10, 20, 30, 40, 50, and 60µg/ml of the iron oxide nanoparticle. Cell viability was determined at 12 and 24 hours after treatment which showed significant decreases when concentration and time period increased. Conclusion: The main mechanism of nanoparticles action is still unknown, but in vivo and in vitro studies in different environments suggest that they are capable of producing reactive oxygen species (ROS. Therefore, they may have an effect on the concentration of intracellular calcium, activation of transcription factors, and changes in cytokine. The results of this study show that the higher concentration and duration of treatment of cells with iron oxide nanoparticles increase the rate of cell death.

  3. Tunability of Size and Magnetic Moment of Iron Oxide Nanoparticles Synthesized by Forced Hydrolysis

    Directory of Open Access Journals (Sweden)

    Ben Sutens

    2016-07-01

    Full Text Available To utilize iron oxide nanoparticles in biomedical applications, a sufficient magnetic moment is crucial. Since this magnetic moment is directly proportional to the size of the superparamagnetic nanoparticles, synthesis methods of superparamagnetic iron oxide nanoparticles with tunable size are desirable. However, most existing protocols are plagued by several drawbacks. Presented here is a one-pot synthesis method resulting in monodisperse superparamagnetic iron oxide nanoparticles with a controllable size and magnetic moment using cost-effective reagents. The obtained nanoparticles were thoroughly characterized by transmission electron microscopy (TEM, X-ray diffraction (XRD and Fourier transform infrared (FT-IR measurements. Furthermore, the influence of the size on the magnetic moment of the nanoparticles is analyzed by superconducting quantum interference device (SQUID magnetometry. To emphasize the potential use in biomedical applications, magnetic heating experiments were performed.

  4. Characterization, Quantification, and Determination of the Toxicity of Iron Oxide Nanoparticles to the Bone Marrow Cells

    Directory of Open Access Journals (Sweden)

    Sae-Yeol-Rim Paik

    2015-09-01

    Full Text Available Iron oxide nanoparticles (IONPs have been used to develop iron supplements for improving the bioavailability of iron in patients with iron deficiency, which is one of the most serious nutritional deficiencies in the world. Accurate information about the characteristics, concentration, and cytotoxicity of IONPs to the developmental and reproductive cells enables safe use of IONPs in the supplement industry. The objective of this study was to analyze the physicochemical properties and cytotoxicity of IONPs in bone marrow cells. We prepared three different types of iron samples (surface-modified iron oxide nanoparticles (SMNPs, IONPs, and iron citrate and analyzed their physicochemical properties such as particle size distribution, zeta potential, and morphology. In addition, we examined the cytotoxicity of the IONPs in various kinds of bone marrow cells. We analyzed particle size distribution, zeta potential, iron levels, and subcellular localization of the iron samples in bone marrow cells. Our results showed that the iron samples were not cytotoxic to the bone marrow cells and did not affect the expression of cell surface markers and lipopolysaccharide (LPS-induced the secretion of cytokines by murine bone marrow-derived dendritic cells (BMDCs. Our results may be used to investigate the interactions between nanoparticles and cells and tissues and the developmental toxicity of nanoparticles.

  5. Influence of synthesis parameters on iron nanoparticle size and zeta potential

    Science.gov (United States)

    Goldstein, Nikki; Greenlee, Lauren F.

    2012-03-01

    Zero valent iron nanoparticles are of increasing interest in clean water treatment applications due to their reactivity toward organic contaminants and their potential to degrade a variety of compounds. This study focuses on the effect of organophosphate stabilizers on nanoparticle characteristics, including particle size distribution and zeta potential, when the stabilizer is present during nanoparticle synthesis. Particle size distributions from DLS were obtained as a function of stabilizer type and iron precursor (FeSO4·7H2O or FeCl3), and nanoparticles from 2 to 200 nm were produced. Three different organophosphate stabilizer compounds were compared in their ability to control nanoparticle size, and the size distributions obtained for particle volume demonstrated differences caused by the three stabilizers. A range of stabilizer-to-iron (0.05-0.9) and borohydride-to-iron (0.5-8) molar ratios were tested to determine the effect of concentration on nanoparticle size distribution and zeta potential. The combination of ferrous sulfate and ATMP or DTPMP phosphonate stabilizer produced stabilized nanoparticle suspensions, and the stabilizers tested resulted in varying particle size distributions. In general, higher stabilizer concentrations resulted in smaller nanoparticles, and excess borohydride did not decrease nanoparticle size. Zeta potential measurements were largely consistent with particle size distribution data and indicated the stability of the suspensions. Probe sonication, as a nanoparticle resuspension method, was minimally successful in several different organic solvents.

  6. Influence of synthesis parameters on iron nanoparticle size and zeta potential

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, Nikki; Greenlee, Lauren F., E-mail: lauren.greenlee@nist.gov [National Institute of Standards and Technology, Materials Reliability Division (United States)

    2012-03-15

    Zero valent iron nanoparticles are of increasing interest in clean water treatment applications due to their reactivity toward organic contaminants and their potential to degrade a variety of compounds. This study focuses on the effect of organophosphate stabilizers on nanoparticle characteristics, including particle size distribution and zeta potential, when the stabilizer is present during nanoparticle synthesis. Particle size distributions from DLS were obtained as a function of stabilizer type and iron precursor (FeSO{sub 4}{center_dot}7H{sub 2}O or FeCl{sub 3}), and nanoparticles from 2 to 200 nm were produced. Three different organophosphate stabilizer compounds were compared in their ability to control nanoparticle size, and the size distributions obtained for particle volume demonstrated differences caused by the three stabilizers. A range of stabilizer-to-iron (0.05-0.9) and borohydride-to-iron (0.5-8) molar ratios were tested to determine the effect of concentration on nanoparticle size distribution and zeta potential. The combination of ferrous sulfate and ATMP or DTPMP phosphonate stabilizer produced stabilized nanoparticle suspensions, and the stabilizers tested resulted in varying particle size distributions. In general, higher stabilizer concentrations resulted in smaller nanoparticles, and excess borohydride did not decrease nanoparticle size. Zeta potential measurements were largely consistent with particle size distribution data and indicated the stability of the suspensions. Probe sonication, as a nanoparticle resuspension method, was minimally successful in several different organic solvents.

  7. Influence of synthesis parameters on iron nanoparticle size and zeta potential

    International Nuclear Information System (INIS)

    Goldstein, Nikki; Greenlee, Lauren F.

    2012-01-01

    Zero valent iron nanoparticles are of increasing interest in clean water treatment applications due to their reactivity toward organic contaminants and their potential to degrade a variety of compounds. This study focuses on the effect of organophosphate stabilizers on nanoparticle characteristics, including particle size distribution and zeta potential, when the stabilizer is present during nanoparticle synthesis. Particle size distributions from DLS were obtained as a function of stabilizer type and iron precursor (FeSO 4 ·7H 2 O or FeCl 3 ), and nanoparticles from 2 to 200 nm were produced. Three different organophosphate stabilizer compounds were compared in their ability to control nanoparticle size, and the size distributions obtained for particle volume demonstrated differences caused by the three stabilizers. A range of stabilizer-to-iron (0.05–0.9) and borohydride-to-iron (0.5–8) molar ratios were tested to determine the effect of concentration on nanoparticle size distribution and zeta potential. The combination of ferrous sulfate and ATMP or DTPMP phosphonate stabilizer produced stabilized nanoparticle suspensions, and the stabilizers tested resulted in varying particle size distributions. In general, higher stabilizer concentrations resulted in smaller nanoparticles, and excess borohydride did not decrease nanoparticle size. Zeta potential measurements were largely consistent with particle size distribution data and indicated the stability of the suspensions. Probe sonication, as a nanoparticle resuspension method, was minimally successful in several different organic solvents.

  8. Super paramagnetic iron oxide nanoparticle modified mancozeb imprinted polymer

    Science.gov (United States)

    Kumar, Sunil; Madhuri, Rashmi; Sharma, Prashant K.

    2017-05-01

    An electrochemical sensor for detection of mancozeb from soil and vegetable sample using molecularly imprinted star polymer modified with iron oxide nanoparticles (SPIONs) is described in this work. We have prepared SPIONS by hydrothermal method and modified with vinyl silane to introduce double bond at their surface. The vinyl group modified SPIONs were used to form mancozeb imprinted star polymer (ISP). The ISPs have specific recognition ability high adsorption capacity towards their template molecule and could be easily extracted from complex matrices using a simple magnet. The prepared polymer was well characterized by field emissive scanning electron microscopy (FE-SEM). Under the optimum condition, the prepared sensor shows good response for mancozeb in the range of 5.96 to 222.39 µg L-1 (detection limit=0.98 µg L-1). The proposed sensors have highly selective for detection of mancozeb in soil and vegetable samples also.

  9. Heterobifunctional PEG Ligands for Bioconjugation Reactions on Iron Oxide Nanoparticles

    Science.gov (United States)

    Bloemen, Maarten; Van Stappen, Thomas; Willot, Pieter; Lammertyn, Jeroen; Koeckelberghs, Guy; Geukens, Nick; Gils, Ann; Verbiest, Thierry

    2014-01-01

    Ever since iron oxide nanoparticles have been recognized as promising scaffolds for biomedical applications, their surface functionalization has become even more important. We report the synthesis of a novel polyethylene glycol-based ligand that combines multiple advantageous properties for these applications. The ligand is covalently bound to the surface via a siloxane group, while its polyethylene glycol backbone significantly improves the colloidal stability of the particle in complex environments. End-capping the molecule with a carboxylic acid introduces a variety of coupling chemistry possibilities. In this study an antibody targeting plasminogen activator inhibitor-1 was coupled to the surface and its presence and binding activity was assessed by enzyme-linked immunosorbent assay and surface plasmon resonance experiments. The results indicate that the ligand has high potential towards biomedical applications where colloidal stability and advanced functionality is crucial. PMID:25275378

  10. Superparamagnetic iron oxide nanoparticles (SPIONs) for targeted drug delivery

    Science.gov (United States)

    Garg, Vijayendra K.; Kuzmann, Erno; Sharma, Virender K.; Kumar, Arun; Oliveira, Aderbal C.

    2016-10-01

    Studies of superparamagnetic iron oxide nanoparticles (SPIONs) have been extensively carried out. Since the earlier work on Mössbauer studies on SPIONs in 1970s, many biomedical applications and their uses in innovative methods to produce new materials with improved performance have appeared. Applications of SPIONs in environmental remediation are also forthcoming. Several different methods of synthesis and coating of the magnetic particles have been described in the literature, and Mössbauer spectroscopy has been an important tool in the characterization of these materials. It is quite possible that the interpretation of the Mössbauer spectra might not be entirely correct because the possible presence of maghemite in the end product of SPIONs might not have been taken into consideration. Nanotechnology is an emerging field that covers a wide range of new technologies under development in nanoscale (1 to 100 nano meters) to produce new products and methodology.

  11. Synthesis and heating effect of iron/iron oxide composite and iron oxide nanoparticles.

    Science.gov (United States)

    Zeng, Q; Baker, I; Loudis, J A; Liao, Y F; Hoopes, P J

    2007-02-09

    Fe/Fe oxide nanoparticles, in which the core consists of metallic Fe and the shell is composed of Fe oxides, were obtained by reduction of an aqueous solution of FeCl 3 within a NaBH 4 solution, or, using a water-in-oil micro-emulsion with CTAB as the surfactant. The reduction was performed either in an inert atmosphere or in air, and passivation with air was performed to produce the Fe/Fe 3 O 4 core/shell composite. Phase identification and particle size were determined by X-ray diffraction and TEM. Thermal analysis was performed using a differential scanning calorimeter. The quasistatic magnetic properties were measured using a VSM, and the specific absorption rates (SARs) of both Fe oxide and Fe/Fe 3 O 4 composite nanoparticles either dispersed in methanol or in an epoxy resin were measured by Luxtron fiber temperature sensors in an alternating magnetic field of 150 Oe at 250 kHz. It was found that the preparation conditions, including the concentrations of solutions, the mixing procedure and the heat treatment, influence the particle size, the crystal structure and consequently the magnetic properties of the particles. Compared with Fe oxides, the saturation magnetization ( M S ) of Fe/Fe 3 O 4 particles (100-190 emu/g) can be twice as high, and the coercivity ( H C ) can be tunable from several Oe to several hundred Oe. Hence, the SAR of Fe/Fe 3 O 4 composite nanoparticles can be much higher than that of Fe oxides, with a maximum SAR of 345 W/g. The heating behavior is related to the magnetic behavior of the nanoparticles.

  12. Surface functionalization of dopamine coated iron oxide nanoparticles for various surface functionalities

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, Jennifer; Xu, Yaolin; Lovas, Kira [Chemical and Biological Engineering, The University of Alabama, Tuscaloosa , AL 35487 (United States); Qin, Ying [Alabama Innovation and Mentoring of Entrepreneurs, The University of Alabama, Tuscaloosa, AL 35487 (United States); Bao, Yuping, E-mail: ybao@eng.ua.edu [Chemical and Biological Engineering, The University of Alabama, Tuscaloosa , AL 35487 (United States)

    2017-04-01

    We present effective conjugation of four small molecules (glutathione, cysteine, lysine, and Tris(hydroxymethyl)aminomethane) onto dopamine-coated iron oxide nanoparticles. Conjugation of these molecules could improve the surface functionality of nanoparticles for more neutral surface charge at physiological pH and potentially reduce non-specific adsorption of proteins to nanoparticles surfaces. The success of conjugation was evaluated with dynamic light scattering by measuring the surface charge changes and Fourier transform infrared spectroscopy for surface chemistry analysis. The stability of dopamine-coated nanoparticles and the ability of conjugated nanoparticles to reduce the formation of protein corona were evaluated by measuring the size and charge of the nanoparticles in biological medium. This facile conjugation method opens up possibilities for attaching various surface functionalities onto iron oxide nanoparticle surfaces for biomedical applications.

  13. Surface functionalization of dopamine coated iron oxide nanoparticles for various surface functionalities

    International Nuclear Information System (INIS)

    Sherwood, Jennifer; Xu, Yaolin; Lovas, Kira; Qin, Ying; Bao, Yuping

    2017-01-01

    We present effective conjugation of four small molecules (glutathione, cysteine, lysine, and Tris(hydroxymethyl)aminomethane) onto dopamine-coated iron oxide nanoparticles. Conjugation of these molecules could improve the surface functionality of nanoparticles for more neutral surface charge at physiological pH and potentially reduce non-specific adsorption of proteins to nanoparticles surfaces. The success of conjugation was evaluated with dynamic light scattering by measuring the surface charge changes and Fourier transform infrared spectroscopy for surface chemistry analysis. The stability of dopamine-coated nanoparticles and the ability of conjugated nanoparticles to reduce the formation of protein corona were evaluated by measuring the size and charge of the nanoparticles in biological medium. This facile conjugation method opens up possibilities for attaching various surface functionalities onto iron oxide nanoparticle surfaces for biomedical applications.

  14. Iron nanoparticles embedded in carbon films: structural and optical properties

    Science.gov (United States)

    Mashayekhi, Fatemeh; Shafiekhani, Azizollah; Sebt, Seyed Ali

    2016-06-01

    In the present work amorphous hydrogenated carbon films with sputtered iron nanoparticles (Fe NPs @ a-C:H) were deposited by co-deposition of RF-sputtering and RF-plasma enhanced chemical vapor deposition methods using acetylene gas and iron target on quartz and silicon substrates. Samples were prepared in different initial pressures and during constant deposition time. The crystalline structure of Fe NPs @ a-C:H was studied using X-ray diffraction and selected area electron diffraction patterns. The X-ray photoelectron spectroscopy analysis presents that increasing the initial pressure decreases the atomic ratio of Fe/C and the sp3-hybridized carbon content in prepared samples. The transmission electron microscope image shows the encapsulated Fe NPs in carbon films. The optical properties and localized surface plasmon resonance (LSPR) of samples were studied using UV-visible spectrophotometry, which is shown that increasing of Fe content decreases the intensity of LSPR peak and increases the optical band gap.

  15. Synthesis, characterization and mechanistic insights of mycogenic iron oxide nanoparticles

    Science.gov (United States)

    Bhargava, Arpit; Jain, Navin; Barathi L., Manju; Akhtar, Mohd. Sayeed; Yun, Yeoung-Sang; Panwar, Jitendra

    2013-11-01

    In the present study, extracellular synthesis of iron oxide nanoparticles (IONPs) was achieved using Aspergillus japonicus isolate AJP01. The isolate demonstrated its ability to hydrolyze the precursor salt solution, a mixture of iron cyanide complexes, under ambient conditions. Hydrolysis of these complexes released ferric and ferrous ions, which underwent protein-mediated coprecipitation and controlled nucleation resulting in the formation of IONPs. Transmission electron microscopy, selected area electron diffraction pattern, energy dispersive spectroscopy and grazing incidence X-ray diffraction analysis confirmed the mycosynthesis of IONPs. The synthesized particles were cubic in shape with a size range of 60-70 nm with crystal structure corresponding to magnetite. Scanning electron microscopy analysis revealed the absence of IONPs on fungal biomass surface, indicating the extracellular nature of synthesis. Fourier transform infrared spectroscopy confirmed the presence of proteins on as-synthesised IONPs, which may confer their stability. Preliminary investigation indicated the role of proteins in the synthesis and stabilization of IONPs. On the basis of present findings, a probable mechanism for synthesis of IONPs is suggested. The simplicity and versatility of the present approach can be utilized for the synthesis of other nanomaterials.

  16. Superparamagnetic Iron Oxide Nanoparticle-Based Delivery Systems for Biotherapeutics

    Science.gov (United States)

    Mok, Hyejung; Zhang, Miqin

    2014-01-01

    Introduction Superparamagnetic iron oxide nanoparticle (SPION)-based carrier systems have many advantages over other nanoparticle-based systems. They are biocompatible, biodegradable, facilely tunable, and superparamagnetic and thus controllable by an external magnetic field. These attributes enable their broad biomedical applications. In particular, magnetically-driven carriers are drawing considerable interest as an emerging therapeutic delivery system because of their superior delivery efficiency. Area covered This article reviews the recent advances in use of SPION-based carrier systems to improve the delivery efficiency and target specificity of biotherapeutics. We examine various formulations of SPION-based delivery systems, including SPION micelles, clusters, hydrogels, liposomes, and micro/nanospheres, as well as their specific applications in delivery of biotherapeutics. Expert opinion Recently, biotherapeutics including therapeutic cells, proteins and genes have been studied as alternative treatments to various diseases. Despite the advantages of high target specificity and low adverse effects, clinical translation of biotherapeutics has been hindered by the poor stability and low delivery efficiency compared to chemical drugs. Accordingly, biotherapeutic delivery systems that can overcome these limitations are actively pursued. SPION-based materials can be ideal candidates for developing such delivery systems because of their excellent biocompatibility and superparamagnetism that enables long-term accumulation/retention at target sites by utilization of a suitable magnet. In addition, synthesis technologies for production of finely-tuned, homogeneous SPIONs have been well developed, which may promise their rapid clinical translation. PMID:23199200

  17. Are iron oxide nanoparticles safe? Current knowledge and future perspectives.

    Science.gov (United States)

    Valdiglesias, Vanessa; Fernández-Bertólez, Natalia; Kiliç, Gözde; Costa, Carla; Costa, Solange; Fraga, Sonia; Bessa, Maria Joao; Pásaro, Eduardo; Teixeira, João Paulo; Laffon, Blanca

    2016-12-01

    Due to their unique physicochemical properties, including superparamagnetism, iron oxide nanoparticles (ION) have a number of interesting applications, especially in the biomedical field, that make them one of the most fascinating nanomaterials. They are used as contrast agents for magnetic resonance imaging, in targeted drug delivery, and for induced hyperthermia cancer treatments. Together with these valuable uses, concerns regarding the onset of unexpected adverse health effects following exposure have been also raised. Nevertheless, despite the numerous ION purposes being explored, currently available information on their potential toxicity is still scarce and controversial data have been reported. Although ION have traditionally been considered as biocompatible - mainly on the basis of viability tests results - influence of nanoparticle surface coating, size, or dose, and of other experimental factors such as treatment time or cell type, has been demonstrated to be important for ION in vitro toxicity manifestation. In vivo studies have shown distribution of ION to different tissues and organs, including brain after passing the blood-brain barrier; nevertheless results from acute toxicity, genotoxicity, immunotoxicity, neurotoxicity and reproductive toxicity investigations in different animal models do not provide a clear overview on ION safety yet, and epidemiological studies are almost inexistent. Much work has still to be done to fully understand how these nanomaterials interact with cellular systems and what, if any, potential adverse health consequences can derive from ION exposure. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Synthesis and toxicity characterization of carbon coated iron oxide nanoparticles with highly defined size distributions.

    Science.gov (United States)

    Mendes, Rafael Gregorio; Koch, Britta; Bachmatiuk, Alicja; El-Gendy, Ahmed Aboud; Krupskaya, Yulia; Springer, Armin; Klingeler, Rüdiger; Schmidt, Oliver; Büchner, Bernd; Sanchez, Samuel; Rümmeli, Mark Hermann

    2014-01-01

    Iron oxide nanoparticles hold great promise for future biomedical applications. To this end numerous studies on iron oxide nanoparticles have been conducted. One aspect these studies reveal is that nanoparticle size and shape can trigger different cellular responses through endocytic pathways, cell viability and early apoptosis. However, systematic studies investigating the size dependence of iron oxide nanoparticles with highly defined diameters across multiple cells lines are not available yet. Iron oxide nanoparticles with well-defined size distributions were prepared. All samples were thoroughly characterized and the cytotoxicity for four standard cell lines (HeLa Kyoto, human osteosarcoma (U2OS), mouse fibroblasts (NIH 3T3) and mouse macrophages (J7442)) where investigated. Our findings show that small differences in size distribution (ca. 10nm) of iron oxide nanoparticles do not influence cytotoxicity, while uptake is size dependent. Cytotoxicity is dose-dependent. Broad distributions of nanoparticles are more easily internalized as compared to the narrow distributions for two of the cell lines tested (HeLa Kyoto and mouse macrophages (J7442)). The data indicate that it is not feasible to probe changes in cytotoxicity within a small size range (10nm). However, TEM investigations of the nanoparticles indicate that cellular uptake is size dependent. The present work compares narrow and broad distributions for various samples of carbon-coated iron oxide nanoparticles. The data highlights that cells differentiate between nanoparticle sizes as indicated by differences in cellular uptake. This information provides valuable knowledge to better understand the interaction of nanoparticles and cells. © 2013.

  19. Biocompatible capped iron oxide nanoparticles for Vibrio cholerae detection

    International Nuclear Information System (INIS)

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

    2015-01-01

    We report the studies relating to fabrication of an efficient immunosensor for Vibrio cholerae detection. Magnetite (iron oxide (Fe 3 O 4 )) nanoparticles (NPs) have been synthesized by the co-precipitation method and capped by citric acid (CA). These NPs were electrophoretically deposited onto indium-tin-oxide (ITO)-coated glass substrate and used for immobilization of monoclonal antibodies against Vibrio cholerae (Ab) and bovine serum albumin (BSA) for Vibrio cholerae detection using an electrochemical technique. The structural and morphological studies of Fe 3 O 4 and CA-Fe 3 O 4 /ITO were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) techniques. The average crystalline size of Fe 3 O 4 , CA-Fe 3 O 4 nanoparticles obtained were about 29 ± 1 nm and 37 ± 1 nm, respectively. The hydrodynamic radius of the nanoparticles was found to be 77.35 nm (Fe 3 O 4 ) and 189.51 nm (CA-Fe 3 O 4 ) by DLS measurement. The results of electrochemical response studies of the fabricated BSA/Ab/CA-Fe 2 O 3 /ITO immunosensor exhibits a good detection range of 12.5–500 ng mL −1 with a low detection limit of 0.32 ng mL −1 , sensitivity 0.03 Ω/ng ml −1 cm −2 , and reproducibility more than 11 times. (paper)

  20. Synthesis and characterization of iron-cobalt (FeCo) alloy nanoparticles supported on carbon

    DEFF Research Database (Denmark)

    Koutsopoulos, Sotiris; Barfod, Rasmus; Eriksen, Kim Michael

    2017-01-01

    Iron-cobalt nanocrystaline bimetallic alloys supported on carbon microparticles were synthesized and characterized. The preparation methods involved the use of iron and cobalt chloride or acetate precursor salts in water and direct co-precipitation or wet impregnation techniques. The size...... of the alloy nanoparticles differed depending on the preparation method. When the wet impregnation technique of acetate precursor salts of Fe and Co were used for the synthesis, the size of FeCo alloy nanoparticles was approximately 13 nm. FeCo alloy nanoparticles were characterized by crystallography (XRD...... and mechanically stable for prolonged periods of time. AFM analysis showed that the FeCo nanoparticles were formed on the surface of the carrier. The results of this study suggest that using these easy and inexpensive synthetic methods iron-cobalt nanoparticles can be formed on carbon microparticles support...

  1. Effect of radiation energy and intracellular iron dose on iron oxide nanoparticle enhancement of radiation cytotoxicity

    Science.gov (United States)

    Mazur, Courtney M.; Strawbridge, Rendall R.; Thompson, Ella S.; Petryk, Alicia A.; Gladstone, David J.; Hoopes, P. Jack

    2015-03-01

    Iron oxide nanoparticles (IONPs) are one of several high-Z materials currently being investigated for their ability to enhance the cytotoxic effects of therapeutic ionizing radiation. Studies with iron oxide, silver, gold, and hafnium oxide suggest radiation dose, radiation energy, cell type, and the type and level of metallic nanoparticle are all critical factors in achieving radiation enhancement in tumor cells. Using a single 4 Gy radiation dose, we compared the level of tumor cell cytotoxicity at two different intracellular iron concentrations and two different radiation energies in vitro. IONPs were added to cell culture media at concentrations of 0.25 mg Fe/mL and 1.0 mg Fe/mL and incubated with murine breast adenocarcinoma (MTG-B) cells for 72 hours. Extracellular iron was then removed and cells were irradiated at either 662 keV or 10 MV. At the 0.25 mg Fe/mL dose (4 pg Fe/cell), radiation energy did not affect the level of cytotoxicity. However with 1.0 mg Fe/mL (9 pg Fe/cell), the higher 10 MV radiation energy resulted in 50% greater cytotoxicity as compared to cells without IONPs irradiated at this energy. These results suggest IONPs may be able to significantly enhance the cytotoxic effects of radiation and improve therapeutic ratio if they can be selectively associated with cancer cells and/or tumors. Ongoing in vivo studies of IONP radiation enhancement in a murine tumor model are too immature to draw conclusions from at this time, however preliminary data suggests similar effectiveness of IONP radiation enhancement at 6 MV and 18 MV energy levels. In addition to the IONP-based radiation enhancement demonstrated here, the use of tumor-localized IONP with an externally delivered, non-toxic alternating magnetic field affords the opportunity to selectively heat and kill tumor cells. Combining IONP-based radiation sensitization and heat-based cytotoxicity provides a unique and potentially highly effective opportunity for therapeutic ratio enhancement.

  2. Iron oxide nanoparticles may damage to the neural tissue through iron accumulation, oxidative stress, and protein aggregation.

    Science.gov (United States)

    Yarjanli, Zahra; Ghaedi, Kamran; Esmaeili, Abolghasem; Rahgozar, Soheila; Zarrabi, Ali

    2017-06-26

    In the recent decade, iron oxide nanoparticles (IONPs) have been proposed for several applications in the central nervous system (CNS), including targeting amyloid beta (Aβ) in the arteries, inhibiting the microglial cells, delivering drugs, and increasing contrast in magnetic resonance imaging. Conversely, a notable number of studies have reported the role of iron in neurodegenerative diseases. Therefore, this study has reviewed the recent studies to determine whether IONPs iron can threaten the cellular viability same as iron. Iron contributes in Fenton's reaction and produces reactive oxygen species (ROS). ROS cause to damage the macromolecules and organelles of the cell via oxidative stress. Iron accumulation and oxidative stress are able to aggregate some proteins, including Aβ and α-synuclein, which play a critical role in Alzheimer's and Parkinson's diseases, respectively. Iron accumulation, oxidative stress, and protein aggregation make a positive feedback loop, which can be toxic for the cell. The release of iron ions from IONPs may result in iron accumulation in the targeted tissue, and thus, activate the positive feedback loop. However, the levels of IONPs induced toxicity depend on the size, concentration, surface charge, and the type of coating and functional groups of IONPs. IONPs depending on their properties can lead to iron accumulation, oxidative stress and protein aggregation in the neural cells. Therefore, in order to apply IONPs in the CNS, the consideration of IONPs properties is crucial.

  3. Scalable fractionation of iron oxide nanoparticles using a CO2 gas-expanded liquid system

    International Nuclear Information System (INIS)

    Vengsarkar, Pranav S.; Xu, Rui; Roberts, Christopher B.

    2015-01-01

    Iron oxide nanoparticles exhibit highly size-dependent physicochemical properties that are important in applications such as catalysis and environmental remediation. In order for these size-dependent properties to be effectively harnessed for industrial applications scalable and cost-effective techniques for size-controlled synthesis or size separation must be developed. The synthesis of monodisperse iron oxide nanoparticles can be a prohibitively expensive process on a large scale. An alternative involves the use of inexpensive synthesis procedures followed by a size-selective processing technique. While there are many techniques available to fractionate nanoparticles, many of the techniques are unable to efficiently fractionate iron oxide nanoparticles in a scalable and inexpensive manner. A scalable apparatus capable of fractionating large quantities of iron oxide nanoparticles into distinct fractions of different sizes and size distributions has been developed. Polydisperse iron oxide nanoparticles (2–20 nm) coated with oleic acid used in this study were synthesized using a simple and inexpensive version of the popular coprecipitation technique. This apparatus uses hexane as a CO 2 gas-expanded liquid to controllably precipitate nanoparticles inside a 1L high-pressure reactor. This paper demonstrates the operation of this new apparatus and for the first time shows the successful fractionation results on a system of metal oxide nanoparticles, with initial nanoparticle concentrations in the gram-scale. The analysis of the obtained fractions was performed using transmission electron microscopy and dynamic light scattering. The use of this simple apparatus provides a pathway to separate large quantities of iron oxide nanoparticles based upon their size for use in various industrial applications.

  4. RGD-conjugated iron oxide magnetic nanoparticles for magnetic resonance imaging contrast enhancement and hyperthermia.

    Science.gov (United States)

    Zheng, S W; Huang, M; Hong, R Y; Deng, S M; Cheng, L F; Gao, B; Badami, D

    2014-03-01

    The purpose of this study was to develop a specific targeting magnetic nanoparticle probe for magnetic resonance imaging and therapy in the form of local hyperthermia. Carboxymethyl dextran-coated ultrasmall superparamagnetic iron oxide nanoparticles with carboxyl groups were coupled to cyclic arginine-glycine-aspartic peptides for integrin α(v)β₃ targeting. The particle size, magnetic properties, heating effect, and stability of the arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide were measured. The arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide demonstrates excellent stability and fast magneto-temperature response. Magnetic resonance imaging signal intensity of Bcap37 cells incubated with arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide was significantly decreased compared with that incubated with plain ultrasmall superparamagnetic iron oxide. The preferential uptake of arginine-glycine-aspartic-ultrasmall superparamagnetic iron oxide by target cells was further confirmed by Prussian blue staining and confocal laser scanning microscopy.

  5. Mössbauer study of iron carbide nanoparticles produced by laser ablation in alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Amagasa, S., E-mail: B115608@ed.tus.ac.jp; Nishida, N. [Tokyo University of Science, Department of Chemistry (Japan); Kobayashi, Y. [The University of Electro-Communications, Graduate School of Informatics and Engineering (Japan); Yamada, Y. [Tokyo University of Science, Department of Chemistry (Japan)

    2016-12-15

    Iron carbide nanoparticles were synthesized by laser ablation of iron in alcohols (methanol and ethanol). A new cell, designed to allow the ablation to be conducted in a flowing solvent, enabled separation and collection of the nanoparticles immediately after production, thus preventing further photochemical reactions of the colloids. The nanoparticles were investigated using Mössbauer spectroscopy, X-ray diffraction, and transmission electron microscopy. In methanol, they consisted of α-iron, γ-iron, iron carbide, and amorphous paramagnetic iron carbides, whereas in ethanol they consisted of iron carbides and amorphous paramagnetic iron carbides. The difference in products depending on the alcohol was attributed to the different carbon supplies for methanol and ethanol. For both solvents, the average particle size was found to be 16 nm, and the nanoparticles were dispersed in amorphous carbon. We also examined the effect of further laser irradiation of the colloids using stagnant solvent, and the particle size was found to increase and a very small amount of carbonization was observed.

  6. Parametric studies on iron-carbon composite nanoparticles synthesized by laser pyrolysis for increased passivation and high iron content

    Science.gov (United States)

    Dumitrache, F.; Morjan, I.; Fleaca, C.; Birjega, R.; Vasile, E.; Kuncser, V.; Alexandrescu, R.

    2011-04-01

    Iron/iron carbide core and carbon shell nanoparticles with improved magnetic properties were successfully synthesized by laser pyrolysis. As iron and carbon precursors, iron pentacarbonyl and pure or argon-diluted acetylene/ethylene mixtures, respectively, were used. The aim of the present optimization is the improvement of the magnetic properties of the nanomaterials by the increase of the iron percent in powders simultaneously to the maintaining of the protective character of the carbon coverage of nanoparticles. The chemical content and the crystalline structure were monitored by EDX, XRD and TEM techniques. In the first study, the content of acetylene as carbon source was diminished from 75% to 0%. Consequently the percent iron increased from 10 at.% to 28 at.% while oxygen remained relatively constant (around 5 at.%). In the second step, only diluted ethylene was used (maximum 87.5 vol.% Ar). In this case, an increase of iron to 46 at.% is observed. An optimum 50% carbon source dilution was found. Above this value, the carbon content increases and below it, superficial oxidation increases through the diminishing of the carbon shell. The magnetic properties and the Fe phase composition of the Fe-C samples were analyzed by temperature dependent Mössbauer spectroscopy.

  7. Enhanced transport of zerovalent iron nanoparticles in saturated porous media by guar gum

    International Nuclear Information System (INIS)

    Tiraferri, Alberto; Sethi, Rajandrea

    2009-01-01

    In order to ensure adequate mobility of zerovalent iron nanoparticles in natural aquifers, the use of a stabilizing agent is necessary. Polymers adsorbed on the nanoparticle surface will give rise to electrosteric stabilization and will decrease attachment to the surface soil grains. Water saturated sand-packed columns were used in this study to investigate the transport of iron nanoparticle suspensions, bare or modified with the green polymer guar gum. The suspensions were prepared at 154 mg/L particle concentration and 0.5 g/L polymer concentration. Transport experiments were conducted by varying the ionic strength, ionic composition, and approach velocity of the fluid. Nanoparticle deposition rates, attachment efficiencies, and travel distances were subsequently calculated based on the classical particle filtration theory. It was found that bare iron nanoparticles are basically immobile in sandy porous media. In contrast, guar gum is able to ensure significant nanoparticle transport at the tested conditions, regardless of the chemistry of the solution. Attachment efficiency values for guar gum-coated nanoparticles under the various conditions tested were smaller than 0.066. Although the calculated travel distances may not prove satisfactory for field application, the investigation attested the promising role of guar gum to ensure mobility of iron nanoparticles in the subsurface environment.

  8. Antibacterial activity of magnetic iron oxide nanoparticles synthesized by laser ablation in liquid

    International Nuclear Information System (INIS)

    Ismail, Raid A.; Sulaiman, Ghassan M.; Abdulrahman, Safa A.; Marzoog, Thorria R.

    2015-01-01

    In this study, (50–110 nm) magnetic iron oxide (α-Fe 2 O 3 ) nanoparticles were synthesized by pulsed laser ablation of iron target in dimethylformamide (DMF) and sodium dodecyl sulfate (SDS) solutions. The structural properties of the synthesized nanoparticles were investigated by using Fourier Transform Infrared (FT-IR) spectroscopy, UV–VIS absorption, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The effect of laser fluence on the characteristics of these nanoparticles was studied. Antibacterial activities of iron oxide nanoparticles were tested against Gram-positive; Staphylococcus aureus and Gram-negative; Escherichia coli, Pseudomonas aeruginosa and Serratia marcescens. The results showed a noteworthy inhibition on both bacterial strains. The preparation conditions were found to affect significantly the antibacterial activity of these nanoparticles. The synthesized magnetic nanoparticles were used to capture rapidly S. aureus bacteria under the magnetic field effect. - Highlights: • Synthesis magnetic iron oxide nanoparticles by pulsed laser ablation • Antibacterial activity against Gram-positive and Gram-negative bacteria • Captured magnetic nanoparticles by S. aureus bacteria under effect of magnetic field

  9. Synthesis of nanoparticles of vanadium carbide in the ferrite of nodular cast iron

    CERN Document Server

    Fras, E; Guzik, E; Lopez, H

    2005-01-01

    The synthesis method of nanoparticles of vanadium carbide in nodular cast iron is presented. After introduction of this method, the nanoparticles with 10-70 nm of diameter was obtained in the ferrite. The diffraction investigations confirmed that these particles are vanadium carbides of type V/sub 3/C/sub 4/.

  10. Hollow Spheres of Iron Carbide Nanoparticles Encased in Graphitic Layers as Oxygen Reduction Catalysts

    DEFF Research Database (Denmark)

    Hu, Yang; Jensen, Jens Oluf; Zhang, Wei

    2014-01-01

    of uniform iron carbide (Fe3C) nanoparticles encased by graphitic layers, with little surface nitrogen or metallic functionalities. In acidic media the outer graphitic layers stabilize the carbide nanoparticles without depriving them of their catalytic activity towards the oxygen reduction reaction (ORR...

  11. Antibacterial activity of magnetic iron oxide nanoparticles synthesized by laser ablation in liquid

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, Raid A., E-mail: raidismail@yahoo.com [Laser Physics Division, Applied Science Department, University of Technology, Baghdad (Iraq); Sulaiman, Ghassan M. [Biotechnology Division, Applied Science Department, University of Technology, Baghdad (Iraq); Abdulrahman, Safa A. [Laser Physics Division, Applied Science Department, University of Technology, Baghdad (Iraq); Marzoog, Thorria R. [Biotechnology Division, Applied Science Department, University of Technology, Baghdad (Iraq)

    2015-08-01

    In this study, (50–110 nm) magnetic iron oxide (α-Fe{sub 2}O{sub 3}) nanoparticles were synthesized by pulsed laser ablation of iron target in dimethylformamide (DMF) and sodium dodecyl sulfate (SDS) solutions. The structural properties of the synthesized nanoparticles were investigated by using Fourier Transform Infrared (FT-IR) spectroscopy, UV–VIS absorption, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The effect of laser fluence on the characteristics of these nanoparticles was studied. Antibacterial activities of iron oxide nanoparticles were tested against Gram-positive; Staphylococcus aureus and Gram-negative; Escherichia coli, Pseudomonas aeruginosa and Serratia marcescens. The results showed a noteworthy inhibition on both bacterial strains. The preparation conditions were found to affect significantly the antibacterial activity of these nanoparticles. The synthesized magnetic nanoparticles were used to capture rapidly S. aureus bacteria under the magnetic field effect. - Highlights: • Synthesis magnetic iron oxide nanoparticles by pulsed laser ablation • Antibacterial activity against Gram-positive and Gram-negative bacteria • Captured magnetic nanoparticles by S. aureus bacteria under effect of magnetic field.

  12. Small angle neutron scattering study of disordered and crystalline iron nanoparticle assemblies

    International Nuclear Information System (INIS)

    Farrell, D.F.; Ijiri, Y.; Kelly, C.V.; Borchers, J.A.; Rhyne, J.J.; Ding, Y.; Majetich, S.A.

    2006-01-01

    Monodisperse surfactant-coated iron nanoparticles are used to form both disordered nanoparticle assemblies and ordered face-centered cubic nanoparticle crystals. The structural order is probed by small angle X-ray scattering, and the magnetic scattering is studied using small angle neutron scattering. The magnetic scattering corresponding to different length scales is interpreted in terms of collective correlations among the particles within the assemblies

  13. Preparation of human immune effector T cells containing iron-oxide nanoparticles.

    Science.gov (United States)

    Iida, Hironori; Takayanagi, Kosuke; Nakanishi, Takuya; Kume, Akiko; Muramatsu, Kouji; Kiyohara, Yoshio; Akiyama, Yasuto; Osaka, Tetsuya

    2008-12-15

    Preparation of human immune T cells containing iron-oxide nanoparticles was carried out for the development of magnetically mediated immunotherapy. Peripheral blood lymphocytes (PBLs) after the incubation with magnetite nanoparticles were found to contain measurable ferric ions, which suggested the incorporation of magnetite nanoparticles. Transmission electron microscopic (TEM) study indicated that the incorporation of magnetite nanoparticles was mediated by endocytosis of PBLs. Furthermore, the effects of dosages and diameter of magnetite nanoparticles on the magnetite incorporation were investigated, and it was demonstrated that the increase in dosage promoted the incorporation of nanoparticles and the uptake into PBLs was more effective for magnetite nanoparticles, which formed smaller aggregations in medium. Finally, the demonstration of magnetite incorporation into enriched T cells and tumor antigen-specific cytotoxic T lymphocyte (CTL) line promises the achievement of magnetically mediated immunotherapy with tumor-specific CTLs containing magnetic nanoparticles.

  14. Rheological characterization of a magnetorheological ferrofluid using iron nitride nanoparticles

    Science.gov (United States)

    Armijo, Leisha M.; Ahuré-Powell, Louise A.; Wereley, Norman M.

    2015-05-01

    Magnetorheology of a magnetorheological ferrofluid (MRFF) was investigated to study the role of a ferromagnetic nanoparticle (NP) additive in magnetorheological fluids (MRFs). Iron nitride (Fe16N2) NPs, nominally within the diameter range of ˜16-45 nm (spherical NPs) and ˜30-66 nm (cubic NPs), were coated with carboxy-polyethylene glycol (carboxy-PEG) and dispersed in silicone oil in order to produce a magnetic carrier fluid or ferrofluid for two solids loadings: 2 vol. % and 5 vol. %. Conventional spherical carbonyl iron (CI) particles, varying in diameter from 6 to 10 μm, were suspended in the ferrofluid at 25 vol. % solids loading. Rheological properties of the MRFF synthesized with the carboxy-PEG-based ferromagnetic carrier fluid were compared to the MRF synthesized with silicone oil to determine how ferrofluid can influence dynamic viscosity and yield stress. Rheological measurements of both MRF and MRFF samples were carried out using a Paar Physica 300 rheometer to estimate the field-off viscosity and to measure flow curves (i.e., shear stress vs. shear rate) as a function of magnetic field. A Bingham-plastic model was used to characterize the flow curves, and results show that there is an increase in the dynamic viscosity of the MRFF over the MRF. The ferromagnetic carrier fluid greatly increases yield stress as only 2 vol. % of added carboxy-PEG NPs improves the yield stress performance by almost 5%. A second MRFF sample synthesized with 5 vol. % of added carboxy-PEG NPs contained in the ferrofluid significantly enhanced the yield stress performance by 13% over the MRF at the same CI solids loading (25 vol. %).

  15. Synthesis of phase-pure and monodisperse iron oxide nanoparticles by thermal decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Hufschmid, Ryan D.; Arami, Hamed; Ferguson, R. Matthew; Gonzales, Marcela; Teeman, Eric M.; Brush, Lucien N.; Browning, Nigel D.; Krishnan, Kannan M.

    2015-06-03

    We present a comprehensive template for the design and synthesis of iron oxide nanoparticles with control over size, size distribution, phase, and resulting properties. Monodisperse superparamagnetic iron oxide nanoparticles were synthesized by thermal decomposition of three different iron containing precursors (iron oleate, iron pentacarbonyl, and iron oxyhydroxide) in organic solvents under a variety of synthetic conditions. We compare the suitability of these three kinetically controlled synthesis protocols, which have in common the use of iron oleate as a starting precursor or reaction intermediate, for producing nanoparticles with specific size and magnetic properties. Monodisperse particles were produced over a tunable range of sizes from approximately 2-30 nm. Reaction parameters such as precursor concentration, addition of surfactant, temperature, ramp rate, and time were adjusted to kinetically control size and size-distribution. In particular, large quantities of excess surfactant (up to 25:1 molar ratio) alter reaction kinetics and result in larger particles with uniform size; however, there is often a trade-off between large particles and a narrow size distribution. Iron oxide phase is also critical for establishing magnetic properties. As an example, we show the importance of obtaining the required iron oxide phase for application to Magnetic Particle Imaging (MPI), and describe how phase purity can be controlled.

  16. Iron oxide nanoparticles for use in contrast agents in magnetic resonance imaging

    International Nuclear Information System (INIS)

    Oliveira, Elisa M.N. de; Rocha, Maximiliano S. da; Caimi, Priscila de A.; Basso, Nara R. de S.; Zanini, Mara L.; Papaleo, Ricardo M.

    2015-01-01

    In this work were carried out synthesis of iron oxide nanoparticles coated with dextran, comparing the results of using different concentrations of dextran, iron salts, temperature and reaction time. The compounds were analyzed by DLS, XRD, TGA, TEM, FTIR, Zeta Potential and relaxivity. Nanoparticles with dispersion around 10-15 nm and average hydrodynamic diameters of 16-50 nm, with superparamagnetic behavior were obtained. The ratio of the relaxivities (r2/r1) in aqueous solutions was 5.30, close to value of the commercially available iron oxide contrast agents. (author)

  17. Synthesis and magnetic properties of iron nanoparticles confined in highly ordered mesoporous carbons

    International Nuclear Information System (INIS)

    Zhang Taiming; Zhao Donglin; Yin Li; Shen Zengmin

    2010-01-01

    Research highlights: → We employed a simple method to synthesize the iron nanoparticles confined in highly ordered mesoporous carbons (OMCs) with different iron contents under an acidic condition generated from the self-hydrolysis of precursory salt. The iron nanoparticles confined in highly ordered mesoporous carbons have been directly synthesized through a simple soft templating method by using resorcinol-formaldehyde (RF) as a carbon precursor, triblock copolymer Pluronic F127 as a template agent and hydrated iron nitrite as an iron source. → The carbon material exhibited highly ordered mesoporous structure, and the iron nanoparticles were uniformly confined in the OMC walls, and constructed the backbone of the mesoporous structures with carbon. Such self-protected Fe/OMC composites will be promising materials for many applications in the fields of separation, catalysis and drug delivery which could be separated by an appropriate magnetic field. - Abstract: The iron nanoparticles confined in highly ordered mesoporous carbons (OMCs) have been directly synthesized through a simple soft templating method by using resorcinol-formaldehyde (RF) as a carbon precursor, triblock copolymer Pluronic F127 as a template agent and hydrated iron nitrite as an iron source. This synthesis was carried out by the carbonization of the F127/[Fe(H 2 O) 9 ](NO 3 ) 3 /RF composites self-assembled in an acidic medium, which was generated from the self-hydrolysis of precursory salt. The effects of iron loading contents on the morphology, pore feature and magnetic properties of the iron nanoparticles confined in OMCs were characterized by the X-ray diffraction, transmission electron microscopy, nitrogen sorption and vibrating-sample magnetometer measurement. It was found that Fe 3+ was captured by the network of F127/RF and further reduced into metallic Fe nanoparticles during the carbonization. The results showed that the carbon material exhibited highly ordered mesoporous structure

  18. Synthesis and magnetic properties of iron nanoparticles confined in highly ordered mesoporous carbons

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Taiming [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zhao Donglin, E-mail: dlzhao@mail.buct.edu.c [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Yin Li; Shen Zengmin [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2010-10-15

    Research highlights: {yields} We employed a simple method to synthesize the iron nanoparticles confined in highly ordered mesoporous carbons (OMCs) with different iron contents under an acidic condition generated from the self-hydrolysis of precursory salt. The iron nanoparticles confined in highly ordered mesoporous carbons have been directly synthesized through a simple soft templating method by using resorcinol-formaldehyde (RF) as a carbon precursor, triblock copolymer Pluronic F127 as a template agent and hydrated iron nitrite as an iron source. {yields} The carbon material exhibited highly ordered mesoporous structure, and the iron nanoparticles were uniformly confined in the OMC walls, and constructed the backbone of the mesoporous structures with carbon. Such self-protected Fe/OMC composites will be promising materials for many applications in the fields of separation, catalysis and drug delivery which could be separated by an appropriate magnetic field. - Abstract: The iron nanoparticles confined in highly ordered mesoporous carbons (OMCs) have been directly synthesized through a simple soft templating method by using resorcinol-formaldehyde (RF) as a carbon precursor, triblock copolymer Pluronic F127 as a template agent and hydrated iron nitrite as an iron source. This synthesis was carried out by the carbonization of the F127/[Fe(H{sub 2}O){sub 9}](NO{sub 3}){sub 3}/RF composites self-assembled in an acidic medium, which was generated from the self-hydrolysis of precursory salt. The effects of iron loading contents on the morphology, pore feature and magnetic properties of the iron nanoparticles confined in OMCs were characterized by the X-ray diffraction, transmission electron microscopy, nitrogen sorption and vibrating-sample magnetometer measurement. It was found that Fe{sup 3+} was captured by the network of F127/RF and further reduced into metallic Fe nanoparticles during the carbonization. The results showed that the carbon material exhibited

  19. Arc-Discharge Synthesis of Iron Encapsulated in Carbon Nanoparticles for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    S. Chaitoglou

    2014-01-01

    Full Text Available The objective of the present work is to improve the protection against the oxidation that usually appears in core@shell nanoparticles. Spherical iron nanoparticles coated with a carbon shell were obtained by a modified arc-discharge reactor, which permits controlling the diameter of the iron core and the carbon shell of the particles. Oxidized iron nanoparticles involve a loss of the magnetic characteristics and also changes in the chemical properties. Our nanoparticles show superparamagnetic behavior and high magnetic saturation owing to the high purity α-Fe of core and to the high core sealing, provided by the carbon shell. A liquid iron precursor was injected in the plasma spot dragged by an inert gas flow. A fixed arc-discharge current of 40 A was used to secure a stable discharge, and several samples were produced at different conditions. Transmission electron microscopy indicated an iron core diameter between 5 and 9 nm. Selected area electron diffraction provided evidences of a highly crystalline and dense iron core. The magnetic properties were studied up to 5 K temperature using a superconducting quantum interference device. The results reveal a superparamagnetic behaviour, a narrow size distribution (σg=1.22, and an average diameter of 6 nm for nanoparticles having a blocking temperature near 40 K.

  20. Formation of polychlorinated compounds in the combustion of PVC with iron nanoparticles.

    Science.gov (United States)

    Font, Rafael; Gálvez, Araceli; Moltó, Julia; Fullana, Andrés; Aracil, Ignacio

    2010-01-01

    The influence of iron nanoparticles in the fuel-rich combustion of PVC has been studied in this work. Dynamic runs for PVC and the mixture PVC and iron nanoparticles were firstly carried out by TGA-MS in order to study the influence of iron on the compounds evolved in the thermal degradation of PVC. To complete the study both PVC and a mixture of PVC and iron nanoparticles were burnt in a laboratory reactor under two different operating conditions: at 850 degrees C and in two stages, the first one at 375 degrees C and the resulting char cooled and subsequently burnt at 850 degrees C. Carbon oxides, light hydrocarbons, PAHs, chlorophenols, chlorobenzenes and PCDD/Fs were analyzed. It was observed that the mixture of PVC with iron nanoparticles at 375 degrees C greatly enhances the formation of light hydrocarbons and polychlorinated compounds, probably indicating that the presence of iron during the thermal decomposition of PVC causes the formation of iron chloride which may have a high catalytic effect.

  1. Influence of structure of iron nanoparticles in aggregates on their magnetic properties

    Directory of Open Access Journals (Sweden)

    Rosická Dana

    2011-01-01

    Full Text Available Abstract Zero-valent iron nanoparticles rapidly aggregate. One of the reasons is magnetic forces among the nanoparticles. Magnetic field around particles is caused by composition of the particles. Their core is formed from zero-valent iron, and shell is a layer of magnetite. The magnetic forces contribute to attractive forces among the nanoparticles and that leads to increasing of aggregation of the nanoparticles. This effect is undesirable for decreasing of remediation properties of iron particles and limited transport possibilities. The aggregation of iron nanoparticles was established for consequent processes: Brownian motion, sedimentation, velocity gradient of fluid around particles and electrostatic forces. In our previous work, an introduction of influence of magnetic forces among particles on the aggregation was presented. These forces have significant impact on the rate of aggregation. In this article, a numerical computation of magnetic forces between an aggregate and a nanoparticle and between two aggregates is shown. It is done for random position of nanoparticles in an aggregate and random or arranged directions of magnetic polarizations and for structured aggregates with arranged vectors of polarizations. Statistical computation by Monte Carlo is done, and range of dominant area of magnetic forces around particles is assessed.

  2. Toxicity assessment of iron oxide nanoparticles in zebrafish (Danio rerio early life stages.

    Directory of Open Access Journals (Sweden)

    Xiaoshan Zhu

    Full Text Available Iron oxide nanoparticles have been explored recently for their beneficial applications in many biomedical areas, in environmental remediation, and in various industrial applications. However, potential risks have also been identified with the release of nanoparticles into the environment. To study the ecological effects of iron oxide nanoparticles on aquatic organisms, we used early life stages of the zebrafish (Danio rerio to examine such effects on embryonic development in this species. The results showed that ≥10 mg/L of iron oxide nanoparticles instigated developmental toxicity in these embryos, causing mortality, hatching delay, and malformation. Moreover, an early life stage test using zebrafish embryos/larvae is also discussed and recommended in this study as an effective protocol for assessing the potential toxicity of nanoparticles. This study is one of the first on developmental toxicity in fish caused by iron oxide nanoparticles in aquatic environments. The results will contribute to the current understanding of the potential ecotoxicological effects of nanoparticles and support the sustainable development of nanotechnology.

  3. Cell membrane damage by iron nanoparticles: an invitro study

    Directory of Open Access Journals (Sweden)

    Gelare Hajsalimi

    2016-12-01

    Full Text Available Application of nanotechnology in medicinal and biological fields has attracted a great interest in the recent yeras. In this paper the cell membrane leakage induced by iron nanoparticles (Fe-NP against PC12 cell line which is known as a model of nervous system cell line was investigated by the lactate dehydrogenase (LDH test. Therefore, PC12 cells were incubated with different concentration of Fe-NP and test was performed after 48h of incubation of the cells with Fe-NP. The resulting data showed that the Fe-NP induced the damage of PC12 cell membrane in a concentration dependent manner. Hence, it may be concluded that the different cytotoxicty effect of NPs may be referred to the concentration of NPs, type of the NPs and the cells. Indeed, the kind of cytotoxic impacts of NPs on the cells can be reduced by the considering of above-mentioned parameters. The resulting data showed that the Fe-NP induced the damage of PC12 cell membrane in a concentration dependent manner. Hence, it may be concluded that the different cytotoxicty effect of NPs may be referred to the concentration of NPs, type of the NPs and the cells. Indeed, the kind of cytotoxic impacts of NPs on the cells can be reduced by the considering of above-mentioned parameters.

  4. Antibacterial Activity of Green Synthesis of Iron Nanoparticles Using Lawsonia inermis and Gardenia jasminoides Leaves Extract

    Directory of Open Access Journals (Sweden)

    Tayyaba Naseem

    2015-01-01

    Full Text Available Recently, development of reliable experimental protocols for synthesis of metal nanoparticles with desired morphologies and sizes has become a major focus of researchers. Green synthesis of metallic nanoparticles has accumulated an ultimate interest over the last decade due to their distinctive properties that make them applicable in various fields of science and technology. Metal nanoparticles that are synthesized by using plants have emerged as nontoxic and ecofriendly. In this study a very cheap and simple conventional heating method was used to obtain the iron nanoparticles (FeNPs using the leaves extract of Lawsonia inermis and Gardenia jasminoides plant. The iron nanoparticles were characterized by thermal gravimetric analysis (TGA, Fourier transform infrared spectroscopy (FT-IR, transmission electron microscopy (TEM, scanning electron microscopy (SEM, atomic force microscopy (AFM, and X-ray diffraction (XRD. The antibacterial activity was studied against Escherichia coli, Salmonella enterica, Proteus mirabilis, and Staphylococcus aureus by using well-diffusion method.

  5. Acicular iron nanoparticles protected against sintering with aluminium oxide

    Directory of Open Access Journals (Sweden)

    Pozas, R.

    2004-08-01

    Full Text Available Acicular iron nanoparticles have been obtained by thermal reduction with hydrogen of a goethite precursor protected against sintering with Al cations, either by doping during the synthesis or by a further coating and the relation between microstructure and magnetic properties of the final Fe particles has been studied in order to evaluate the efficiency of both protecting methods. Uniform goethite and Al-doped goethite precursors were prepared by oxidation with air of FeSO4 solutions, containing Al(NO33 when required, previously precipitated with Na2CO3, while the Al oxide coating on the undoped goethite precursor was carried out by heterocoagulation. In both protecting methods, Al cations were mainly concentrated in the particle outer layers of the goethite precursors and the final iron. Due to this Al enrichment, the growth of iron crystals during the reduction process is minimised resulting Fe particles with improved coercivity and squareness. Nevertheless, the coating procedure seems to be more effective giving rise to the iron particles with the largest coercivity, probably due to a better preservation of the acicular morphology in this case.

    Se han obtenido nanopartículas aciculares de hierro por reducción térmica con hidrógeno de un precursor acicular de goetita que fue protegido frente a la sinterización por la adición de cationes Al mediante dopado durante su síntesis o por recubrimiento posterior, estudiándose la relación entre la microestructura y las propiedades magnéticas de las partículas finales de α-Fe con objeto de evaluar la eficacia de ambos métodos de protección. Los precursores uniformes de goetita y de goetita dopada con Al se prepararon por oxidación con aire de disoluciones de FeSO4 o de FeSO4 y Al(NO33, previamente precipitadas por la adición de Na2CO3, mientras que el recubrimiento con óxido de aluminio sobre las partículas de goetita fue llevado a cabo por un procedimiento de heterocoagulaci

  6. Iron oxide nanoparticles induce human microvascular endothelial cell permeability through reactive oxygen species production and microtubule remodeling

    Directory of Open Access Journals (Sweden)

    Shi Xianglin

    2009-01-01

    Full Text Available Abstract Background Engineered iron nanoparticles are being explored for the development of biomedical applications and many other industry purposes. However, to date little is known concerning the precise mechanisms of translocation of iron nanoparticles into targeted tissues and organs from blood circulation, as well as the underlying implications of potential harmful health effects in human. Results The confocal microscopy imaging analysis demonstrates that exposure to engineered iron nanoparticles induces an increase in cell permeability in human microvascular endothelial cells. Our studies further reveal iron nanoparticles enhance the permeability through the production of reactive oxygen species (ROS and the stabilization of microtubules. We also showed Akt/GSK-3β signaling pathways are involved in iron nanoparticle-induced cell permeability. The inhibition of ROS demonstrate ROS play a major role in regulating Akt/GSK-3β – mediated cell permeability upon iron nanoparticle exposure. These results provide new insights into the bioreactivity of engineered iron nanoparticles which can inform potential applications in medical imaging or drug delivery. Conclusion Our results indicate that exposure to iron nanoparticles induces an increase in endothelial cell permeability through ROS oxidative stress-modulated microtubule remodeling. The findings from this study provide new understandings on the effects of nanoparticles on vascular transport of macromolecules and drugs.

  7. Versatile and Biomass Synthesis of Iron-based Nanoparticles Supported on Carbon Matrix with High Iron Content and Tunable Reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Dongmao [ORNL; Shi, Sheldon Q [ORNL; Jiang, Dongping [Mississippi State University (MSU); Che, Wen [Mississippi State University (MSU); Gai, Zheng [ORNL; Howe, Jane Y [ORNL; More, Karren Leslie [ORNL; Arockiasamy, Antonyraj [Mississippi State University (MSU)

    2012-01-01

    Iron-based nanoparticles supported on carbon (FeNPs{at}C) have enormous potential for environmental applications. Reported is a biomass-based method for FeNP{at}C synthesis that involves pyrolysis of bleached wood fiber pre-mixed with Fe{sub 3}O{sub 4} nanoparticles. This method allows synthesis of iron-based nanoparticles with tunable chemical reactivity by changing the pyrolysis temperature. The FeNP{at}C synthesized at a pyrolysis temperature of 500 C (FeNP{at}C-500) reacts violently (pyrophoric) when exposed to air, while FeNP{at}C prepared at 800 C (FeNP{at}C-800) remains stable in ambient condition for at least 3 months. The FeNPs in FeNP{at}C-800 are mostly below 50 nm in diameter and are surrounded by carbon. The immediate carbon layer (within 5-15 nm radius) on the FeNPs is graphitized. Proof-of-concept environmental applications of FeNPs{at}C-800 were demonstrated by Rhodamine 6G and arsenate (V) removal from water. This biomass-based method provides an effective way for iron-based nanoparticle fabrication and biomass utilization.

  8. Versatile and biomass synthesis of iron-based nanoparticles supported on carbon matrix with high iron content and tunable reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Dongmao, E-mail: DZ33@msstate.edu [Mississippi State University, Department of Chemistry (United States); Shi, Sheldon Q. [University of North Texas, Mechanical and Energy Engineering (United States); Pittman, Charles U.; Jiang Dongping [Mississippi State University, Department of Chemistry (United States); Che Wen [University of North Texas, Mechanical and Energy Engineering (United States); Gai Zheng; Howe, Jane Y.; More, Karren L. [Oak Ridge National Laboratory, Center for Nanophase Materials Sciences (United States); Antonyraj, Arockiasamy [Mississippi State University, Center for Advanced Vehicular Systems (United States)

    2012-08-15

    Iron-based nanoparticles supported on carbon (FeNPs-C) have enormous potential for environmental applications. Reported is a biomass-based method for FeNP-C synthesis that involves pyrolysis of bleached wood fiber pre-mixed with Fe{sub 3}O{sub 4} nanoparticles. This method allows synthesis of iron-based nanoparticles with tunable chemical reactivity by changing the pyrolysis temperature. The FeNP-C synthesized at a pyrolysis temperature of 500 Degree-Sign C (FeNP-C-500) reacts violently (pyrophoric) when exposed to air, while FeNP-C prepared at 800 Degree-Sign C (FeNP-C-800) remains stable in ambient condition for at least 3 months. The FeNPs in FeNP-C-800 are mostly below 50 nm in diameter and are surrounded by carbon. The immediate carbon layer (within 5-15 nm radius) on the FeNPs is graphitized. Proof-of-concept environmental applications of FeNPs-C-800 were demonstrated by Rhodamine 6G and arsenate (V) removal from water. This biomass-based method provides an effective way for iron-based nanoparticle fabrication and biomass utilization.

  9. A simple gold-coated microstructure fiber polarization filter in two communication windows

    Science.gov (United States)

    Feng, Xinxing; Li, Shuguang; Du, Huijing; Zhang, Yinan; Liu, Qiang

    2018-03-01

    A polarization filter is designed at two communication windows of 1310 and 1550 nm based on microstructured optical fiber. The model has four large diameter air holes and two gold-coated air holes. The influence of the geometrical parameters of the photonic crystal fiber on the performance of the polarization filter is analyzed by the finite element method. The numerical simulation shows that when the fiber length is 300 μm, the corresponding extinction ratio is 209.7 dB and 179.8 dB, the bandwidth of extinction ratio (ER) better than 20 dB is 150 nm and 350 nm at the communication wavelength of 1310 nm and 1550 nm.

  10. Stabilization and cellular delivery of chitosan-polyphosphate nanoparticles by incorporation of iron.

    Science.gov (United States)

    Giacalone, Giovanna; Hillaireau, Hervé; Capiau, Pauline; Chacun, Hélène; Reynaud, Franceline; Fattal, Elias

    2014-11-28

    Chitosan (CS) nanoparticles are typically obtained by complexation with tripolyphosphate (TPP) ions, or more recently using triphosphate group-containing drugs such as adenosine triphosphate (ATP). ATP is an active molecule we aim to deliver in order to restore its depletion in macrophages, when associated with their death leading to plaque rupture in atherosclerotic lesions. Despite high interest in CS nanoparticles for drug delivery, due to the biodegradability of CS and to the ease of the preparation process, these systems tend to readily disintegrate when diluted in physiological media. Some stabilization strategies have been proposed so far but they typically involve the addition of a coating agent or chemical cross-linkers. In this study, we propose the complexation of CS with iron ions prior to nanoparticle formation as a strategy to improve the carrier stability. This can be achieved thanks to the ability of iron to strongly bind both chitosan and phosphate groups. Nanoparticles were obtained from either TPP or ATP and chitosan-iron (CS-Fe) complexes containing 3 to 12% w/w iron. Isothermal titration calorimetry showed that the binding affinity of TPP and ATP to CS-Fe increased with the iron content of CS-Fe complexes. The stability of these nanoparticles in physiological conditions was evaluated by turbidity and by fluorescence fluctuation in real time upon dilution by electrolytes, and revealed an important stabilization effect of CS-Fe compared to CS, increasing with the iron content. Furthermore, in vitro studies on two macrophage cell lines (J774A.1 and THP-1) revealed that ATP uptake is improved consistently with the iron content of CS-Fe/ATP nanoparticles, and correlated to their lower dissociation in biological medium, allowing interesting perspectives for the intracellular delivery of ATP. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Synthesis and characterization of PEG-iron oxide core-shell composite nanoparticles for thermal therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wydra, Robert J.; Kruse, Anastasia M. [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States); Bae, Younsoo [Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40506 (United States); Anderson, Kimberly W. [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States); Hilt, J. Zach, E-mail: hilt@engr.uky.edu [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States)

    2013-12-01

    In this study, core-shell nanoparticles were developed to achieve thermal therapy that can ablate cancer cells in a remotely controlled manner. The core-shell nanoparticles were prepared using atomic transfer radical polymerization (ATRP) to coat iron oxide (Fe{sub 3}O{sub 4}) nanoparticles with a poly(ethylene glycol) (PEG) based polymer shell. The iron oxide core allows for the remote heating of the particles in an alternating magnetic field (AMF). The coating of iron oxide with PEG was verified through Fourier transform infrared spectroscopy and thermal gravimetric analysis. A thermoablation (55 °C) study was performed on A549 lung carcinoma cells exposed to nanoparticles and over a 10 min AMF exposure. The successful thermoablation of A549 demonstrates the potential use of polymer coated particles for thermal therapy. - Highlights: • Utilized atomic transfer radical polymerization (ATRP) to coat iron oxide nanoparticles with PEG • Investigated the surface coating by surface characterization methods • Demonstrated the potential use of nanoparticles for cancer therapy applications.

  12. Application of neutron activation analysis to the corrosion study of gold coated studs used for piercing ears

    International Nuclear Information System (INIS)

    Saiki, M.; Rogero, S.O.; Costa, I.; Correa, O.V.; Higa, O.Z.

    1998-01-01

    Complete text of publication follows. Gold is known as a metal having little or no toxicity and it has been widely used for coating studs for ear piercing. However, for some people gold coated studs have caused serious allergy and inflammation problems. After piercing, the studs are usually kept in the ear lobes for at least one week, and during this period the stud surfaces in contact with the body fluids have caused swelling, pain and redness of the skin. Consequently, it is of great interest to evaluate if elements from the metallic substrate underneath the gold coatings migrate to the body fluids due to the corrosion and the presence of defects in gold coatings. The solutions for corrosion test were obtained by placing the gold coated studs in contact with the solutions of NaCl and of culture medium. Elemental analyses of these solutions by radioanalytical method of neutron activation analysis indicated the occurrence of substrate corrosion since the elements Cr, Fe, Ni and Zn were found in these solutions. These elements are substrate material components of alloys used to make the studs and they were quantified by X-ray fluorescence analysis. The defects of the coatings were also detected by scanning electron microscopy and energy dispersive spectroscopy analysis of the gold coated studs before and after the corrosion tests. Cytotoxicity studies indicated that after corrosion test the solution used was toxic in the culture cell assay. Among the elements quantified in the test solutions, Ni is considered responsible for most of allergic reactions. Results obtained in this work indicated the necessity to improve quality control of the coating process of studs and in the appropriate choice of material used as substrate

  13. Oxytetracycline Delivery in Adult Female Zebrafish by Iron Oxide Nanoparticles.

    Science.gov (United States)

    Chemello, Giulia; Piccinetti, Chiara; Randazzo, Basilio; Carnevali, Oliana; Maradonna, Francesca; Magro, Massimiliano; Bonaiuto, Emanuela; Vianello, Fabio; Radaelli, Giuseppe; Fifi, Anna Paola; Gigliotti, Federica; Olivotto, Ike

    2016-12-01

    Recently, the indiscriminate use of antibiotics in the aquaculture sector has raised public concern because of possible toxic effects, development of bacterial resistance, and accumulation of residues in individual tissues. Even if several countries have developed regulations about their use, it is clear that long-term growth of the aquaculture industry requires both ecologically sound practices and sustainable resource management. Alternative strategies for better management of antibiotic administration are of primary interest to improve absorption rates and, as a consequence, to reduce their release into the aquatic environment. The present study investigates, for the first time to our knowledge, a new methodology for oxytetracycline (OTC) administration through the use of iron oxide nanoparticles (NPs) (made of maghemite γ-Fe 2 O 3 ) in zebrafish (Danio rerio). Fish were divided into 4 experimental groups: control; group A exposed to 4 mg/L OTC (through water); group B exposed to the 100 mg/L SAMNs@OTC complex (equivalent to 4 mg/L OTC), and group C exposed to bare NPs. No detoxification processes or anatomical alterations were observed in fish exposed to bare NPs. Exposure of fish to the SAMNs@OTC complex resulted in a 10 times higher OTC accumulation with respect to using water exposure. This new OTC administration method seems much more efficient with respect to the traditional way of exposure and has the potentiality to reduce antibiotic utilization and possible environmental impacts. However, the dynamics related to OTC release from the SAMNs@OTC complex are still not clear and need further investigations.

  14. Ultrasonic computed tomography imaging of iron oxide nanoparticles

    Science.gov (United States)

    Perlman, Or; Azhari, Haim

    2017-02-01

    Iron oxide nanoparticles (IONPs) are becoming increasingly used and intensively investigated in the field of medical imaging. They are currently FDA approved for magnetic resonance imaging (MRI), and it would be highly desirable to visualize them by ultrasound as well. Previous reports using the conventional ultrasound B-scan (pulse-echo) imaging technique have shown very limited detectability of these particles. The aim of this study is to explore the feasibility of imaging IONPs using the through-transmission ultrasound methodology and demonstrate their detectability using ultrasonic computed tomography (UCT). Commercially available IONPs were acoustically analysed to quantify their effect on the speed of sound (SOS) and acoustic attenuation as a function of concentration. Next, through-transmission projection and UCT imaging were performed on a breast mimicking phantom and on an ex vivo tissue model, to which IONPs were injected. Finally, an MRI scan was performed to verify that the same particles examined in the ultrasound experiment can be imaged by magnetic resonance, using the same clinically relevant concentrations. The results have shown a consistent concentration dependent speed of sound increase (1.86 \\text{m}{{\\text{s}}^{-1}} rise per 100 µg · ml-1 IONPs). Imaging based on this property has shown a substantial contrast-to-noise ratio improvement (up to 5 fold, p  <  0.01). The SOS-related effect generated a well discernible image contrast and allowed the detection of the particles existence and location, in both raster-scan projection and UCT imaging. Conversely, no significant change in the acoustic attenuation coefficient was noted. Based on these findings, it is concluded that IONPs can be used as an effective SOS-based contrast agent, potentially useful for ultrasonic breast imaging. Furthermore, the particle offers the capacity of significantly enhancing diagnosis accuracy using multimodal MRI-ultrasound imaging capabilities.

  15. Iron oxide nanoparticles with different polymer coatings for photothermal therapy

    Science.gov (United States)

    Yang, Jia; Fan, Lu; Xu, Yanhong; Xia, Jindong

    2017-10-01

    Iron oxide nanoparticles (Fe3O4 NPs) have attracted significant attention in view of their potential applications in biomedicine. Surface coatings or modifications are generally needed to improve the colloidal stability of Fe3O4 NPs in a physiological environment. In this study, Fe3O4 NPs in the size range of 12-15 nm coated with polyacrylic acid (PAA), poly(vinyl alcohol) (PVA), and polyethyleneimine (PEI) were synthesized through a mild reduction route to investigate their potential for photothermal therapy. The polymer-coated Fe3O4 NPs dispersed well in water and formed stable colloids; the surface charges of the particles were dependent on the nature of the surface coating. The strong absorption in the near-infrared (NIR) region enabled the coated Fe3O4 NPs to be used as agents in photothermal therapy. The photothermal conversion efficiency of PEI-coated Fe3O4 NPs (PEI-Fe3O4 NPs) distinctly decreased when exposed to a cell culture medium. In addition, PEI-Fe3O4 NPs showed higher cytotoxicity and enhanced cellular uptake efficiency when compared to PAA-coated Fe3O4 NPs (PAA-Fe3O4 NPs) and PVA-coated Fe3O4 NPs (PVA-Fe3O4 NPs). This study highlights the importance of optimizing the surface properties of Fe3O4 NPs when using them in biomedical applications and provides guidelines for the design and development of functional Fe3O4 NPs for cancer therapy. [Figure not available: see fulltext.

  16. Iron nanoparticles grown in a carbon arc discharge

    NARCIS (Netherlands)

    Zhang, G.L.; du Marchie van Voorthuysen, E.H.; Szymanski, K.; Boom, G; Verwerft, M.G M; Jonkman, H.T.; Niesen, L

    1996-01-01

    Iron particles, encapsulated by graphite layers, were produced by means of the Kratschmer are discharge method in an iron pentacarbonyl atmosphere. The Mossbauer effect is dominated by the vibration of the particles as a whole. Superparamagnetism is dominant for iron oxide particles. No endohedral

  17. Fate and Transport of Superparamagentic Iron Oxide Nanoparticles in Porous Media

    Science.gov (United States)

    Aksoy, D.; Ziylan, A.; Ince, N. H.; Yagci Acar, F.; Copty, N. K.

    2008-12-01

    The increased use of engineered nanoparticles in various applications such as electronics and biomedical engineering has raised concerns about their impact on human health and the environment. In this study we investigate the fate and transport in porous media of super paramagnetic iron oxide (SPIO) nanoparticles surface coated with poly acrylic acid for size stabilization. The nanoparticle size distribution was first analyzed to assess the effect of dilution on the particle size. It was found that the poly acrylic acid is generally effective in stabilizing the size of the nanoparticles, except for highly diluted solutions. Sorption batch experiments performed at different pH values showed that the SPIO nanoparticles did not adsorb significantly on sand. Transport experiments were conducted in a sand-packed column for different SPIO injection concentrations and for upwards and downwards flow conditions. Comparison of the nanoparticle breakthrough curves to that of a conservative tracer showed that while advection and dispersion are the two main mechanisms responsible for the tracer transport, nanoparticle transport is also strongly influenced by the nanoparticle concentration in the solution. At low concentrations (in the range of 1 mg/L) the high levels of dilution mean that only a small portion of the nanoparticles get transported due to their larger effective size. Another consequence of the concentration-dependent mobility of the nanoparticles is sharper breakthrough curves compared to that of the tracer. Overall, the results demonstrate the significance of concentration on nanoparticle size and, consequently, transport. These results also point to the need for effective nanoparticle size control for the efficient deliverability of reactive nanoparticles (such as zero-valent iron) in in-situ groundwater remediation applications.

  18. Effect of coating thickness of iron oxide nanoparticles on their relaxivity in the MRI.

    Science.gov (United States)

    Hajesmaeelzadeh, Farzaneh; Shanehsazzadeh, Saeed; Grüttner, Cordula; Daha, Fariba Johari; Oghabian, Mohammad Ali

    2016-02-01

    Iron oxide nanoparticles have found prevalent applications in various fields including drug delivery, cell separation and as contrast agents. Super paramagnetic iron oxide (SPIO) nanoparticles allow researchers and clinicians to enhance the tissue contrast of an area of interest by increasing the relaxation rate of water. In this study, we evaluate the dependency of hydrodynamic size of iron oxide nanoparticles coated with Polyethylene glycol (PEG) on their relativities with 3 Tesla clinical MRI. We used three groups of nanoparticles with nominal sizes 20, 50 and 100 nm with a core size of 8.86 nm, 8.69 nm and 10.4 nm that they were covered with PEG 300 and 600 Da. A clinical magnetic resonance scanner determines the T1 and T2 relaxation times for various concentrations of PEG-coated nanoparticles. The size measurement by photon correlation spectroscopy showed the hydrodynamic sizes of MNPs with nominal 20, 50 and 100 nm with 70, 82 and 116 nm for particles with PEG 600 coating and 74, 93 and 100 nm for particles with PEG 300 coating, respectively. We foud that the relaxivity decreased with increasing overall particle size (via coating thickness). Magnetic resonance imaging showed that by increasing the size of the nanoparticles, r2/r1 increases linearly. According to the data obtained from this study it can be concluded that increments in coating thickness have more influence on relaxivities compared to the changes in core size of magnetic nanoparticles.

  19. Direct sputtering- and electro-deposition of gold coating onto the closed surface of ultralow-density carbon-hydrogen foam cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Jiaqiu; Yin, Jialing; Zhang, Hao; Yao, Mengqi; Hu, Wencheng, E-mail: huwc@uestc.edu.cn

    2016-12-15

    Highlights: • The surface pores of P(DVB/St) foam cylinder are sealed by CVD method. • Gold film was deposited on the surface of foam cylinder by magnetron sputtering. • Electroless plating was excluded in the present experiments. • The gold coatings were thickened through the electrodeposition process. - Abstract: This work aimed to fabricate a gold coating on the surface of ultralow-density carbon-hydrogen foam cylinder without electroless plating. Poly (divinylbenzene/styrene) foam cylinder was synthetized by high internal phase emulsion, and chemical vapor deposition polymerization approach was used to form a compact poly-p-xylylene film on the foam cylinder. Conducting gold thin films were directly deposited onto the poly-p-xylylene-modified foam cylinder by magnetron sputtering, and electrochemical deposition was adopted to thicken the gold coatings. The micro-structures and morphologies of poly (divinylbenzene/styrene) foam cylinder and gold coating were observed by field-emission scanning electron microscopy. The gold coating content was investigated by energy-dispersive X-ray. The thicknesses of poly-p-xylylene coating and sputtered gold thin-film were approximately 500 and 100 nm, respectively. After electrochemical deposition, the thickness of gold coating increased to 522 nm, and the gold coating achieved a compact and uniform structure.

  20. Immobilization of Iron Nanoparticles on Multi Substrates and Its Reduction Removal of Chromium (VI) from Waste Streams

    Science.gov (United States)

    This article describes the in-situ synthesis and immobilization of iron nanoparticles on several substrates at room temperature using NaBH4 as a reducing agent and ascorbic acid as capping agent. The method is very effective in protecting iron nanoparticles from air oxidation for...

  1. Transport and Development of Microemulsionand Surfactant Stabilized Iron Nanoparticles for In Situ Remediation

    Science.gov (United States)

    Hsu, Dennis

    This work describes the mobility assessments of microemulsion-stabilized iron oxide nanoparticles and anionic surfactant sodium diethyl hexyl phosphate (SDEHP)-stabilized nanoscale zero valent iron (NZVI) particles in laboratory porous media. The two formulations tested in this work achieved stable iron nanoparticle suspensions for months and prepared via a simple "one-pot" synthesis method developed by Wang et al. Both formulations were tested under field scale velocity of 5 m/day with no mechanical aid during the injection. A three-compartment model, involving colloid diffusion theory, diffusion theory and tailing was applied to describe the breakthrough curves of the studies. The obtained breakthrough curves of both formulations implied excellent transport in porous media with steady plateau C/Co at 0.8-0.9 and recovery of up to 0.95 for SDEHP stabilized NZVI. Post analysis on the retention of iron on the porous media implied ideal transport with consistent data to the breakthrough curves.

  2. Ultrafast electron and energy transfer in dye-sensitized iron oxide and oxyhydroxide nanoparticles

    DEFF Research Database (Denmark)

    Gilbert, Benjamin; Katz, Jordan E.; Huse, Nils

    2013-01-01

    –310 fs were found for all samples. Comparison between TA dynamics on uncoated and dye-sensitized hematite nanoparticles revealed the dye de-excitation pathway to consist of a competition between electron and energy transfer to the nanoparticles. We analyzed the TA data for hematite nanoparticles using...... a four-state model of the dye-sensitized system, finding electron and energy transfer to occur on the same ultrafast timescale. The interfacial electron transfer rates for iron oxides are very close to those previously reported for DCF-sensitized titanium dioxide (for which dye–oxide energy transfer...... photo-initiated interfacial electron transfer. This approach enables time-resolved study of the fate and mobility of electrons within the solid phase. However, complete analysis of the ultrafast processes following dye photoexcitation of the sensitized iron(iii) oxide nanoparticles has not been reported...

  3. Study of Iron oxide nanoparticles using Mössbauer spectroscopy with a high velocity resolution

    Science.gov (United States)

    Oshtrakh, M. I.; Ushakov, M. V.; Šepelák, V.; Semionkin, V. A.; Morais, P. C.

    2016-01-01

    Iron oxide (magnetite and maghemite) nanoparticles developed for magnetic fluids were studied using Mössbauer spectroscopy with a high velocity resolution at 295 and 90 K. The recorded Mössbauer spectra have demonstrated that usual physical models based on octahedral and tetrahedral sites were not suitable for fitting. Alternatively, the Mössbauer spectra were nicely fitted using a large number of magnetic sextets. The obtained results showed that the Mössbauer spectra and the assessed parameters were different for nanoparticles as-prepared and dispersed in the dispersing fluid at 295 K. We claim that this finding is mainly due to the interaction of polar molecules with Iron cations at nanoparticle's surface or due to the surface coating using carboxylic-terminated molecules. It is assumed that the large number of spectral components may be related to complexity of the nanoparticle's characteristics and deviations from stoichiometry, including in the latter the influence of the oxidation of magnetite towards maghemite.

  4. Influence of gold coating and interplate voltage on the performance of chevron micro-channel plates for temporally and spatially resolved single particle detection

    Science.gov (United States)

    Hoendervanger, A. L.; Clément, D.; Aspect, A.; Westbrook, C. I.; Dowek, D.; Picard, Y. J.; Boiron, D.

    2013-02-01

    We present a study of two different sets of Micro-Channel Plates used for time and space resolved single particle detection. We investigate the effects of the gold coating and that of introducing an interplate voltage between the spatially separated plates. We find that the gold coating increases the count rate of the detector and the pulse amplitude as previously reported for non-spatially resolved setups. The interplate voltage also increases count rates. In addition, we find that a non-zero interplate voltage improves the spatial accuracy in determining the arrival position of incoming single particles (by ˜20%) while the gold coating has a negative effect (by ˜30%).

  5. Effect of the Surfactant on the Growth and Oxidation of Iron Nanoparticles

    Directory of Open Access Journals (Sweden)

    Alvaro Ruíz-Baltazar

    2015-01-01

    Full Text Available Fe nanoparticles and branched nanostructures of iron oxide were synthesized by chemical reduction in aqueous phase. The mechanism of formation of iron oxides as a function of the amount of surfactant employed during the synthesis process was studied. Specifically Fe, Fe2O3, and Fe3O4 nanoparticles were obtained. The oxidation of Fe to Fe3O4 and finally to Fe2O3 was carried out by oxidative etching process, decreasing the amount of stabilizer agent. The structures obtained were characterized by high resolution (HRTEM and scanning/transmission (STEM electron microcopies, energy dispersive spectroscopy (EDS, and optical spectroscopy (UV-Vis and IR.

  6. Doxorubicin loaded PVA coated iron oxide nanoparticles for targeted drug delivery

    International Nuclear Information System (INIS)

    Kayal, S.; Ramanujan, R.V.

    2010-01-01

    Magnetic drug targeting is a drug delivery system that can be used in locoregional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by coprecipitation of iron oxide followed by coating with polyvinyl alcohol (PVA). Characterization was carried out using X-ray diffraction, TEM, TGA, FTIR and VSM techniques. The magnetic core of the carriers was magnetite (Fe 3 O 4 ), with average size of 10 nm. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. The amount of PVA bound to the iron oxide nanoparticles were estimated by thermogravimetric analysis (TGA) and the attachment of PVA to the iron oxide nanoparticles was confirmed by FTIR analysis. Doxorubicin (DOX) drug loading and release profiles of PVA coated iron oxide nanoparticles showed that up to 45% of adsorbed drug was released in 80 h, the drug release followed the Fickian diffusion-controlled process. The binding of DOX to the PVA was confirmed by FTIR analysis. The present findings show that DOX loaded PVA coated iron oxide nanoparticles are promising for magnetically targeted drug delivery.

  7. Enhanced Congo red dye removal from aqueous solutions using iron nanoparticles: adsorption, kinetics, and equilibrium studies.

    Science.gov (United States)

    Kim, Se-Ho; Choi, Pyuck-Pa

    2017-11-14

    We report on the Congo red dye removal properties of body centred cubic and amorphous iron nanoparticles, synthesized by a facile borohydride reduction method under ambient conditions. We have analyzed the adsorption of Congo red as a function of dye concentration, time, and temperature and measured a Congo red adsorption capacity of 1735 mg g -1 for the amorphous iron nanoparticles. To our knowledge, this is the highest value reported so far for Congo red adsorption. The acquired data have been evaluated applying various models for adsorption kinetics and thermodynamic studies. The isotherm models as well as acquired Fourier transform infrared spectra suggest that both chemi- and physisorption occur for Congo red adsorption on iron nanoparticles, where chemisorption appears to be dominant. The kinetics of adsorption of Congo red on both bcc-structured and amorphous iron follow a pseudo-second order equation and are characterized by high initial adsorption rates. Diffusion studies indicate that adsorption occurs in two stages, namely film diffusion followed by intraparticle diffusion. Our studies show that amorphous iron nanoparticles are highly promising for dye adsorption and wastewater treatment applications.

  8. In vitro biological validation and cytocompatibility evaluation of hydrogel iron-oxide nanoparticles

    Science.gov (United States)

    Catalano, Enrico

    2017-08-01

    Superparamagnetic iron oxide nanoparticles (MNPs) have recently been investigated for their excellent biocompatibility as well as multi-purpose biomedical potential with promising results, owing to their ability to be targeted and heated by magnetic fields. In this study, novel hydrogel, chitosan Fe3O4 magnetic nanoparticles were synthesized for possible use for induced magnetic hyperthermia, and targeted drug delivery. The coating of iron oxide nanoparticles plays a key-role to efficiently improve internalization of nanoparticles in many cell types. Targeting is also highly desirable for these applications. In this regard hydrophilic coating like chitosan was used to improve drug release. Uncoated (Fe3O4)and chitosan-coated iron oxide nanoparticles (CS-Fe3O4) were synthesized and characterized from the biological point of view. The aim of this study was to provide an in vitro evaluation of the cytocompatibility of Fe3O4 and CS-Fe3O4 MNPs by using different in vitro evaluation tests. In this context, the cytocompatibility and cytotoxic effects of uncoated and hydrogel chemically-engineered chitosan-coated iron oxide NPs were investigated according to the ISO standard 10993-5:2009. Fe3O4 and CS-Fe3O4 NPs were tested on human mammary epithelial cells (MCF-10A) by using direct and not direct contact cytotoxicity evaluation tests, by evaluating influence of the iron particles on the cytoskeleton with phalloidin/DAPI staining and in vitro cellular iron uptake with Perl's Prussian blue staining. The results indicate that uncoated and chitosan-coated iron oxide nanoparticles are cytocompatible, without negative influence on the cytoskeleton or higher accumulation of iron in the cytoplasm. Therefore, it is encouraging that our data suggest uncoated and chitosan-coated iron oxide nanoparticles have satisfactory proliferative and viability effects on MCF-10A cells. In conclusion data suggest that both MNP types may be differently aimed in biomedical application in relation

  9. Iron Oxide Nanoparticle-Based Magnetic Ink Development for Fully Printed Tunable Radio-Frequency Devices

    KAUST Repository

    Vaseem, Mohammad

    2018-01-30

    The field of printed electronics is still in its infancy and most of the reported work is based on commercially available nanoparticle-based metallic inks. Although fully printed devices that employ dielectric/semiconductor inks have recently been reported, there is a dearth of functional inks that can demonstrate controllable devices. The lack of availability of functional inks is a barrier to the widespread use of fully printed devices. For radio-frequency electronics, magnetic materials have many uses in reconfigurable components but rely on expensive and rigid ferrite materials. A suitable magnetic ink can facilitate the realization of fully printed, magnetically controlled, tunable devices. This report presents the development of an iron oxide nanoparticle-based magnetic ink. First, a tunable inductor is fully printed using iron oxide nanoparticle-based magnetic ink. Furthermore, iron oxide nanoparticles are functionalized with oleic acid to make them compatible with a UV-curable SU8 solution. Functionalized iron oxide nanoparticles are successfully embedded in the SU8 matrix to make a magnetic substrate. The as-fabricated substrate is characterized for its magnetostatic and microwave properties. A frequency tunable printed patch antenna is demonstrated using the magnetic and in-house silver-organo-complex inks. This is a step toward low-cost, fully printed, controllable electronic components.

  10. Effectiveness of hand washing on the removal of iron oxide nanoparticles from human skin ex vivo.

    Science.gov (United States)

    Lewinski, Nastassja A; Berthet, Aurélie; Maurizi, Lionel; Eisenbeis, Antoine; Hopf, Nancy B

    2017-08-01

    In this study, the effectiveness of washing with soap and water in removing nanoparticles from exposed skin was investigated. Dry, nanoscale hematite (α-Fe 2 O 3 ) or maghemite (γ-Fe 2 O 3 ) powder, with primary particle diameters between 20-30 nm, were applied to two samples each of fresh and frozen ex vivo human skin in two independent experiments. The permeation of nanoparticles through skin, and the removal of nanoparticles after washing with soap and water were investigated. Bare iron oxide nanoparticles remained primarily on the surface of the skin, without penetrating beyond the stratum corneum. Skin exposed to iron oxide nanoparticles for 1 and 20 hr resulted in removal of 85% and 90%, respectively, of the original dose after washing. In the event of dermal exposure to chemicals, removal is essential to avoid potential local irritation or permeation across skin. Although manufactured at an industrial scale and used extensively in laboratory experiments, limited data are available on the removal of engineered nanoparticles after skin contact. Our finding raises questions about the potential consequences of nanoparticles remaining on the skin and whether alternative washing methods should be proposed. Further studies on skin decontamination beyond use of soap and water are needed to improve the understanding of the potential health consequences of dermal exposure to nanoparticles.

  11. Functionalization and Area-Selective Deposition of Magnetic Carbon-Coated Iron Nanoparticles from Solution

    Directory of Open Access Journals (Sweden)

    Erika Widenkvist

    2011-01-01

    Full Text Available A route to area-selective deposition of carbon-coated iron nanoparticles, involving chemical modification of the surface of the particles, is described. Partial oxidative etching of the coating introduces carboxylic groups, which then are esterified. The functionalized particles can be selectively deposited on the Si areas of Si/SiO2 substrates by a simple dipping procedure. Nanoparticles and nanoassemblies have been analyzed using SEM, TEM, and XPS.

  12. Ultrasmall iron oxide nanoparticles for biomedical applications: improving the colloidal and magnetic properties.

    Science.gov (United States)

    Costo, Rocio; Bello, Valentina; Robic, Caroline; Port, Marc; Marco, Jose F; Puerto Morales, M; Veintemillas-Verdaguer, Sabino

    2012-01-10

    A considerable increase in the saturation magnetization, M(s) (40%), and initial susceptibility of ultrasmall (<5 nm) iron oxide nanoparticles prepared by laser pyrolysis was obtained through an optimized acid treatment. Moreover, a significant enhancement in the colloidal properties, such as smaller aggregate sizes in aqueous media and increased surface charge densities, was found after this chemical protocol. The results are consistent with a reduction in nanoparticle surface disorder induced by a dissolution-recrystallization mechanism.

  13. Efficient and safe internalization of magnetic iron oxide nanoparticles: two fundamental requirements for biomedical applications.

    Science.gov (United States)

    Calero, Macarena; Gutiérrez, Lucía; Salas, Gorka; Luengo, Yurena; Lázaro, Ana; Acedo, Pilar; Morales, M Puerto; Miranda, Rodolfo; Villanueva, Angeles

    2014-05-01

    We have performed a series of in vitro tests proposed for the reliable assessment of safety associated with nanoparticles-cell interaction. A thorough analysis of toxicity of three different coating iron oxide nanoparticles on HeLa cells has been carried out including, methyl thiazol tetrazolium bromide (MTT) and Trypan blue exclusion tests, cell morphology observation by optical and Scanning Electron Microscopy (SEM), study of cytoskeletal components, analysis of cell cycle and the presence of reactive oxygen species (ROS). We have quantified magnetic nanoparticle internalization, determined possible indirect cell damages and related it to the nanoparticle coating. The results confirm a very low toxicity of the analyzed iron oxide nanoparticles into HeLa cells by multiple assays and pave the way for a more successful cancer diagnostic and treatment without secondary effects. In this paper, three different iron oxide nanoparticles are studied and compared from the standpoint of safety and toxicity in HeLa cells, demonstrating low toxicity for each preparation, and paving the way to potential future clinical applications. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Superparamagnetic iron oxide nanoparticles incorporated into silica nanoparticles by inelastic collision via ultrasonic field: Role of colloidal stability

    Energy Technology Data Exchange (ETDEWEB)

    Sodipo, Bashiru Kayode; Azlan, Abdul Aziz [Nano-Optoelectronics Research and Technology (NOR) Lab, School of Physics, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia Nano-Biotechnology Research (Malaysia); Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia)

    2015-04-24

    Superparamagnetic iron oxide nanoparticles (SPION)/Silica composite nanoparticles were prepared by ultrasonically irradiating colloidal suspension of silica and SPION mixture. Both silica and SPION were synthesized independently via co-precipitation and sol-gel method, respectively. Their mixtures were sonicated at different pH between 3 and 5. Electrophoresis measurement and other physicochemical analyses of the products demonstrate that at lower pH SPION was found incorporated into the silica. However, at pH greater than 4, SPION was unstable and unable to withstand the turbulence flow and shock wave from the ultrasonic field. Results suggest that the formation of the SPION/silica composite nanoparticles is strongly related to the inelastic collision induced by ultrasonic irradiation. More so, the formation the composite nanoparticles via the ultrasonic field are dependent on the zeta potential and colloidal stability of the particles.

  15. Superparamagnetic iron oxide nanoparticles incorporated into silica nanoparticles by inelastic collision via ultrasonic field: Role of colloidal stability

    International Nuclear Information System (INIS)

    Sodipo, Bashiru Kayode; Azlan, Abdul Aziz

    2015-01-01

    Superparamagnetic iron oxide nanoparticles (SPION)/Silica composite nanoparticles were prepared by ultrasonically irradiating colloidal suspension of silica and SPION mixture. Both silica and SPION were synthesized independently via co-precipitation and sol-gel method, respectively. Their mixtures were sonicated at different pH between 3 and 5. Electrophoresis measurement and other physicochemical analyses of the products demonstrate that at lower pH SPION was found incorporated into the silica. However, at pH greater than 4, SPION was unstable and unable to withstand the turbulence flow and shock wave from the ultrasonic field. Results suggest that the formation of the SPION/silica composite nanoparticles is strongly related to the inelastic collision induced by ultrasonic irradiation. More so, the formation the composite nanoparticles via the ultrasonic field are dependent on the zeta potential and colloidal stability of the particles

  16. One-pot synthesis of water soluble iron nanoparticles using rationally-designed peptides and ligand release.

    Science.gov (United States)

    Papst, Stefanie; Cheong, Soshan; Banholzer, Moritz J; Brimble, Margaret A; Williams, David E; Tilley, Richard D

    2013-05-18

    Herein we report the rational design of new phosphopeptides for control of nucleation, growth and aggregation of water-soluble, superparamagnetic iron-iron oxide core-shell nanoparticles. The use of the designed peptides enables a one-pot synthesis that avoids utilizing unstable or toxic iron precursors, organic solvents, and the need for exchange of capping agent after synthesis of the NPs.

  17. Generation of drugs coated iron nanoparticles through high energy ball milling

    International Nuclear Information System (INIS)

    Radhika Devi, A.; Murty, B. S.; Chelvane, J. A.; Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh

    2014-01-01

    The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells

  18. Generation of drugs coated iron nanoparticles through high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Radhika Devi, A.; Murty, B. S. [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Chelvane, J. A. [Defence Metallurgical Research Laboratory, Hyderabad 500058 (India); Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh [Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036 (India)

    2014-03-28

    The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells.

  19. Morphological changes in the kidney, liver and spleen during prolonged administration of iron nanoparticles

    Science.gov (United States)

    Navolokin, N. A.; Maslyakova, G. N.; Bucharskya, A. B.; Kong, X. M.; Zuev, V. V.; Medvedev, B. A.; Ignatiev, A. A.; Bochkaryeva, T. V.

    2012-02-01

    We determined the cytotoxic effect of iron nanoparticles of 70 nm, with a single per oral administration in an experiment on white outbred mice. Morphological changes were evaluated in the internal organs. Thus, changes depend on the concentration of nanoparticles at long-term per oral exposure: identified violations of the structure of the liver, kidneys and spleen as venous plethora and degeneration of cells at 250 and 500 mkg / kg dose of nanoparticles are reversible, changes in the organs were pronounced with a dosage of 1000 mkg / kg.

  20. Complexity of intravenous iron nanoparticle formulations: implications for bioequivalence evaluation.

    Science.gov (United States)

    Pai, Amy Barton

    2017-11-01

    Intravenous iron formulations are a class of complex drugs that are commonly used to treat a wide variety of disease states associated with iron deficiency and anemia. Venofer® (iron-sucrose) is one of the most frequently used formulations, with more than 90% of dialysis patients in the United States receiving this formulation. Emerging data from global markets outside the United States, where many iron-sucrose similars or copies are available, have shown that these formulations may have safety and efficacy profiles that differ from the reference listed drug. This may be attributable to uncharacterized differences in physicochemical characteristics and/or differences in labile iron release. As bioequivalence evaluation guidance evolves, clinicians should be educated on these potential clinical issues before a switch to the generic formulation is made in the clinical setting. © 2017 New York Academy of Sciences.

  1. Magnetic nanoparticles for precision oncology: theranostic magnetic iron oxide nanoparticles for image-guided and targeted cancer therapy.

    Science.gov (United States)

    Zhu, Lei; Zhou, Zhiyang; Mao, Hui; Yang, Lily

    2017-01-01

    Recent advances in the development of magnetic nanoparticles (MNPs) have shown promise in the development of new personalized therapeutic approaches for clinical management of cancer patients. The unique physicochemical properties of MNPs endow them with novel multifunctional capabilities for imaging, drug delivery and therapy, which are referred to as theranostics. To facilitate the translation of those theranostic MNPs into clinical applications, extensive efforts have been made on designing and improving biocompatibility, stability, safety, drug-loading ability, targeted delivery, imaging signal and thermal- or photodynamic response. In this review, we provide an overview of the physicochemical properties, toxicity and theranostic applications of MNPs with a focus on magnetic iron oxide nanoparticles.

  2. Synthesis and characterization of polystyrene coated iron oxide nanoparticles and asymmetric assemblies by phase inversion

    KAUST Repository

    Xie, Yihui

    2014-09-02

    Films with a gradient concentration of magnetic iron oxide nanoparticles are reported, based on a phase inversion membrane process. Nanoparticles with ∼13 nm diameter were prepared by coprecipitation in aqueous solution and stabilized by oleic acid. They were further functionalized by ATRP leading to grafted polystyrene brush. The final nanoparticles of 33 nm diameter were characterized by TGA, FTIR spectroscopy, GPC, transmission electron microscopy, and dynanmic light scattering. Asymmetric porous nanoparticle assemblies were then prepared by solution casting and immersion in water. The nanocomposite film production with functionalized nanoparticles is fast and technically scalable. The morphologies of films were characterized by scanning electron microscopy and atomic force microscopy, demonstrating the presence of sponge-like structures and finger-like cavities when 50 and 13 wt % casting solutions were, respectively, used. The magnetic properties were evaluated using vibrating sample magnetometer.

  3. Antibacterial Efficacy of Iron-Oxide Nanoparticles against Biofilms on Different Biomaterial Surfaces

    Directory of Open Access Journals (Sweden)

    Monica Thukkaram

    2014-01-01

    Full Text Available Biofilm growth on the implant surface is the number one cause of the failure of the implants. Biofilms on implant surfaces are hard to eliminate by antibiotics due to the protection offered by the exopolymeric substances that embed the organisms in a matrix, impenetrable for most antibiotics and immune cells. Application of metals in nanoscale is considered to resolve biofilm formation. Here we studied the effect of iron-oxide nanoparticles over biofilm formation on different biomaterial surfaces and pluronic coated surfaces. Bacterial adhesion for 30 min showed significant reduction in bacterial adhesion on pluronic coated surfaces compared to other surfaces. Subsequently, bacteria were allowed to grow for 24 h in the presence of different concentrations of iron-oxide nanoparticles. A significant reduction in biofilm growth was observed in the presence of the highest concentration of iron-oxide nanoparticles on pluronic coated surfaces compared to other surfaces. Therefore, combination of polymer brush coating and iron-oxide nanoparticles could show a significant reduction in biofilm formation.

  4. Iron nanoparticles from blood coated with collagen as a matrix for ...

    Indian Academy of Sciences (India)

    A simple wet precipitation technique was used to prepare nanobiocomposite containing iron nanoparticles coated with collagen. This nanobiocomposite was used as matrix for the synthesis of nanohydroxyapatite. The physicochemical characteristic studies of the nanohydroxyapatite thus formed were carried out using ...

  5. Oxidative stress response in neural stem cells exposed to different superparamagnetic iron oxide nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Pongrac, I. M.; Pavičić, I.; Milić, M.; Brkić Ahmed, L.; Babič, Michal; Horák, Daniel; Vinković Vrček, I.; Gajović, S.

    2016-01-01

    Roč. 11, 26 April (2016), s. 1701-1715 ISSN 1176-9114 R&D Projects: GA ČR(CZ) GC16-01128J EU Projects: European Commission(XE) 316120 - GLOWBRAIN Institutional support: RVO:61389013 Keywords : superparamagnetic iron oxide nanoparticles * biocompatibility * oxidative stress Subject RIV: CD - Macromolecular Chemistry

  6. Whole Body Retention and Distribution of Orally-Adminsitered Radiolabeled Zerovalent Iron nanoparticles in Mice

    Science.gov (United States)

    Zerovalent iron nanoparticles (nZVI) are used for in situ remediation of contaminated ground water, raising the possibility that nZVI particles or their altered residues could contaminate the ground water. Therefore, it is important to study their effects on humans and other orga...

  7. Iron(II,III)-polyphenol complex nanoparticles derived from green tea with remarkable ecotoxicological impact

    Science.gov (United States)

    There are several greener methods exist to synthesize zero–valent iron nanoparticles (nZVI) using different bio-based reducing agents. Although their useful properties in degradation of organic dyes, chlorinated organics, or arsenic have been described earlier, their characteriza...

  8. Preparation of tunable-sized iron nanoparticles based on magnetic manipulation in inert gas condensation (IGC)

    NARCIS (Netherlands)

    Xing, Lijuan; ten Brink, Gert H.; Kooi, Bart J.; Palasantzas, George

    2017-01-01

    Iron nanoparticles (NPs) prepared by inert gas condensation were studied using high resolution transmission electron microscopy and Wulff construction shape analysis. The NP size and shape show strong dependence on the magnetic field above the target surface. The effect of the magnetic field could

  9. Alternating magnetic field energy absorption in the dispersion of iron oxide nanoparticles in a viscous medium

    Czech Academy of Sciences Publication Activity Database

    Smolkova, I.S.; Kazantseva, N.E.; Babayan, V.; Smolka, P.; Parmar, H.; Vilcakova, J.; Schneeweiss, Oldřich; Pizúrová, Naděžda

    2015-01-01

    Roč. 374, JAN (2015), s. 508-515 ISSN 0304-8853 Institutional support: RVO:68081723 Keywords : Iron oxide nanoparticles * Coprecipitation * Magnetic interactions * Specific loss power * Hyperthermia Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.357, year: 2015

  10. Biocompatible Colloidal Suspensions Based on Magnetic Iron Oxide Nanoparticles: Synthesis, Characterization and Toxicological Profile

    Science.gov (United States)

    Coricovac, Dorina-Elena; Moacă, Elena-Alina; Pinzaru, Iulia; Cîtu, Cosmin; Soica, Codruta; Mihali, Ciprian-Valentin; Păcurariu, Cornelia; Tutelyan, Victor A.; Tsatsakis, Aristidis; Dehelean, Cristina-Adriana

    2017-01-01

    The use of magnetic iron oxide nanoparticles in biomedicine has evolved intensely in the recent years due to the multiple applications of these nanomaterials, mainly in domains like cancer. The aim of the present study was: (i) to develop biocompatible colloidal suspensions based on magnetic iron oxide nanoparticles as future theranostic tools for skin pathology and (ii) to test their effects in vitro on human keratinocytes (HaCat cells) and in vivo by employing an animal model of acute dermal toxicity. Biocompatible colloidal suspensions were obtained by coating the magnetic iron oxide nanoparticles resulted during the solution combustion synthesis with a double layer of oleic acid, as innovative procedure in increasing bioavailability. The colloidal suspensions were characterized in terms of dynamic light scattering (DLS) and transmission electron microscopy (TEM). The in vitro effects of these suspensions were tested by means of Alamar blue assay and the noxious effects at skin level were measured using non-invasive methods. The in vitro results indicated a lack of toxicity on normal human cells induced by the iron oxide nanoparticles colloidal suspensions after an exposure of 24 h to different concentrations (5, 10, and 25 μg·mL−1). The dermal acute toxicity test showed that the topical applications of the colloidal suspensions on female and male SKH-1 hairless mice were not associated with significant changes in the quality of barrier skin function. PMID:28400730

  11. Electrocatalytic detection of dopamine at single-walled carbon nanotubes–iron (III) oxide nanoparticles platform

    CSIR Research Space (South Africa)

    Adekunle, AS

    2010-06-01

    Full Text Available Electrochemical sensors using edge-plane pyrolytic graphite electrode (EPPGEs) modified with singlewall carbon nanotubes–iron (III) oxide (SWCNT/Fe2O3) nanoparticles for the sensitive detection of dopamine (DA) are described for the first time...

  12. Iron nanoparticles from blood coated with collagen as a matrix for ...

    Indian Academy of Sciences (India)

    Keywords. Collagen; iron nanoparticle; nanohydroxyapatite; MTT assay; wet precipitation method. 1. Introduction. Bone is a type of connective tissue mainly composed of an organic component, collagen and an inorganic component, nanocrystalline carbonate hydroxyapatite. This type of bio- logical hybrid material finds ...

  13. High yield, facile aqueous synthesis and characterization of C18 functionalized iron oxide nanoparticles

    Science.gov (United States)

    Nair, Kishore Kumar; Kaur, Ranjeet; Iqbal, Nusrat; Hasan, Abshar; Alam, Samsul; Raza, S. K.

    2015-04-01

    The present study shows the synthesis of magnetite nanoparticles by co-precipitation method in three steps. The steps involve the precipitation of Fe3O4 nanoparticles followed by layer by layer functionalization with silica and tetraethoxy(octadyl)silane (C18). The prepared magnetite nanoparticles were investigated by SEM, TEM, XRD, FTIR and VSM. It was suggested that the intermediate iron oxide nanoparticles were formed by the competing processes of oxidation and crystal growth after decomposition of ferrous and ferric salts. The first step synthesized nanoparticles were of around 16 ± 4 nm, second step silica coating of 18 ± 3 nm and the final step C18 were of 56 ± 6 nm. The tetraethylorthosilicate hydrolyzed to form silicic acid which further polymerizes and thereby forms a layer of silica over magnetite nanoparticles. FTIR peaks at 2854 and 2921 cm-1 confirm the layering of C18 on silica encapsulated nanoparticles which corresponds to ˜CH2 and ˜(CH2)17CH3 carbon chain symmetric extension. The thickness of silica coating and C18 are 1.9 ± 0.3 nm and 38.6 ± 2.5 nm as confirmed from TEM size distribution curve. The saturation magnetism of magnetite, silica coated and C18 nanoparticles are 77.46, 74.53 and 68.76 emu g-1 respectively. Thus, Fe3O4, silica and C18 encapsulated magnetite nanoparticles were superparamagnetic.

  14. Modification of the surface of superparamagnetic iron oxide nanoparticles to enable their safe application in humans.

    Science.gov (United States)

    Strehl, Cindy; Maurizi, Lionel; Gaber, Timo; Hoff, Paula; Broschard, Thomas; Poole, A Robin; Hofmann, Heinrich; Buttgereit, Frank

    Combined individually tailored methods for diagnosis and therapy (theragnostics) could be beneficial in destructive diseases, such as rheumatoid arthritis. Nanoparticles are promising candidates for theragnostics due to their excellent biocompatibility. Nanoparticle modifications, such as improved surface coating, are in development to meet various requirements, although safety concerns mean that modified nanoparticles require further review before their use in medical applications is permitted. We have previously demonstrated that iron oxide nanoparticles with amino-polyvinyl alcohol (a-PVA) adsorbed on their surfaces have the unwanted effect of increasing human immune cell cytokine secretion. We hypothesized that this immune response was caused by free-floating PVA. The aim of the present study was to prevent unwanted immune reactions by further surface modification of the a-PVA nanoparticles. After cross-linking of PVA to nanoparticles to produce PVA-grafted nanoparticles, and reduction of their zeta potential, the effects on cell viability and cytokine secretion were analyzed. PVA-grafted nanoparticles still stimulated elevated cytokine secretion from human immune cells; however, this was inhibited after reduction of the zeta potential. In conclusion, covalent cross-linking of PVA to nanoparticles and adjustment of the surface charge rendered them nontoxic to immune cells, nonimmunogenic, and potentially suitable for use as theragnostic agents.

  15. Iron oxide nanoparticles: the Influence of synthesis method and size on composition and magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, M.D., E-mail: mdcarvalho@fc.ul.pt [CCMM/Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, C8, 1749-016 Lisboa (Portugal); Henriques, F. [CCMM/Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, C8, 1749-016 Lisboa (Portugal); Ferreira, L.P. [CFMC/Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Godinho, M.; Cruz, M.M. [CFMC/Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal)

    2013-05-01

    Iron oxide nanoparticles with mean diameter ranging from 7 to 20 nm were synthesized using two routes: the precipitation method in controlled atmosphere and a reduction–precipitation method under air, in some cases followed by a hydrothermal treatment. The smallest nanoparticles were obtained by the reduction–precipitation method. In order to establish the composition of the iron oxide nanoparticles and its relation with size, the morphological, structural and magnetic properties of the prepared samples were investigated using X-ray diffraction, transmission electron microscopy, Mössbauer spectroscopy and SQUID magnetometry. The results allow to conclude that the nanoparticles can be essentially described as Fe3–xO₄, x decreasing with the particle size increase. The composition and magnetic behavior of the synthesized iron oxide nanoparticles are directly related with their size. The overall results are compatible with a core@shell structure model, where a magnetite core is surrounded by an oxidized magnetite layer (labeled as maghemite), the magnetite core dimension depending on the average particle size. - Graphical abstract: TEM images and Mössbauer spectroscopy spectra of Fe3–xO₄ samples with different sizes. Highlights: • Fe3–xO₄ nanoparticles with a mean size between 7 and 20 nm were synthesized. • The smallest nanoparticles were obtained by a reduction precipitation method, under air. • The increase of particles size was succeeded using a hydrothermal treatment at 150 °C. • The magnetic properties of the nanoparticles are directly related with their size.

  16. Efficient internalization of silica-coated iron oxide nanoparticles of different sizes by primary human macrophages and dendritic cells

    International Nuclear Information System (INIS)

    Kunzmann, Andrea; Andersson, Britta; Vogt, Carmen; Feliu, Neus; Ye Fei; Gabrielsson, Susanne; Toprak, Muhammet S.; Buerki-Thurnherr, Tina; Laurent, Sophie; Vahter, Marie; Krug, Harald; Muhammed, Mamoun; Scheynius, Annika; Fadeel, Bengt

    2011-01-01

    Engineered nanoparticles are being considered for a wide range of biomedical applications, from magnetic resonance imaging to 'smart' drug delivery systems. The development of novel nanomaterials for biomedical applications must be accompanied by careful scrutiny of their biocompatibility. In this regard, particular attention should be paid to the possible interactions between nanoparticles and cells of the immune system, our primary defense system against foreign invasion. On the other hand, labeling of immune cells serves as an ideal tool for visualization, diagnosis or treatment of inflammatory processes, which requires the efficient internalization of the nanoparticles into the cells of interest. Here, we compare novel monodispersed silica-coated iron oxide nanoparticles with commercially available dextran-coated iron oxide nanoparticles. The silica-coated iron oxide nanoparticles displayed excellent magnetic properties. Furthermore, they were non-toxic to primary human monocyte-derived macrophages at all doses tested whereas dose-dependent toxicity of the smaller silica-coated nanoparticles (30 nm and 50 nm) was observed for primary monocyte-derived dendritic cells, but not for the similarly small dextran-coated iron oxide nanoparticles. No macrophage or dendritic cell secretion of pro-inflammatory cytokines was observed upon administration of nanoparticles. The silica-coated iron oxide nanoparticles were taken up to a significantly higher degree when compared to the dextran-coated nanoparticles, irrespective of size. Cellular internalization of the silica-coated nanoparticles was through an active, actin cytoskeleton-dependent process. We conclude that these novel silica-coated iron oxide nanoparticles are promising materials for medical imaging, cell tracking and other biomedical applications.

  17. Physio-biochemical basis of iron-sulfide nanoparticle induced growth and seed yield enhancement in B. juncea.

    Science.gov (United States)

    Rawat, Madhu; Nayan, Rajeev; Negi, Bhawana; Zaidi, M G H; Arora, Sandeep

    2017-09-01

    Metal nanoparticles have been reported to influence plant growth and productivity. However, the molecular mechanisms underlying the effects have not been completely understood yet. Current work describes the physio-biochemical basis of iron sulfide nanoparticle induced growth and yield enhancement in Brassica juncea. Iron sulfide nanoparticles (0, 2, 4, 6, 8 and 10 ppm) were used for foliar treatment of B. juncea at 30, 45 and 60 days after sowing, under field conditions. Foliar treatment of 4 ppm iron sulfide nanoparticle solution at 30 days after sowing brought maximal enhancement in agronomic attributes of the treated plants. Results of assays i.e. total chlorophyll, electrolyte leakage, Malondialdehyde (MDA), proline, H 2 O 2 and antioxidant enzyme activities indicated the benign effect of iron sulfide nanoparticles on plants. Consequently, improved redox status of the treated plants, enabled them to assimilate higher photosynthate. The augmentation in growth and seed yield in iron sulfide nanoparticle treated plants was amply supported by activation of RUBISCO small subunit (rubisco S), RUBISCO large subunit (rubisco L), glutamine synthetase (gs) and glutamate synthase (gogat) genes. Thus, iron sulfide nanoparticle induced growth and yield enhancement is proposed to be mediated through activation of carbon and nitrogen assimilatory pathways at specific growth stage. The iron content in the leaves and root tissues of the treated plants was also significantly improved. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Rapid microwave-assisted synthesis of dextran-coated iron oxide nanoparticles for magnetic resonance imaging.

    Science.gov (United States)

    Osborne, Elizabeth A; Atkins, Tonya M; Gilbert, Dustin A; Kauzlarich, Susan M; Liu, Kai; Louie, Angelique Y

    2012-06-01

    Currently, magnetic iron oxide nanoparticles are the only nanosized magnetic resonance imaging (MRI) contrast agents approved for clinical use, yet commercial manufacturing of these agents has been limited or discontinued. Though there is still widespread demand for these particles both for clinical use and research, they are difficult to obtain commercially, and complicated syntheses make in-house preparation unfeasible for most biological research labs or clinics. To make commercial production viable and increase accessibility of these products, it is crucial to develop simple, rapid and reproducible preparations of biocompatible iron oxide nanoparticles. Here, we report a rapid, straightforward microwave-assisted synthesis of superparamagnetic dextran-coated iron oxide nanoparticles. The nanoparticles were produced in two hydrodynamic sizes with differing core morphologies by varying the synthetic method as either a two-step or single-step process. A striking benefit of these methods is the ability to obtain swift and consistent results without the necessity for air-, pH- or temperature-sensitive techniques; therefore, reaction times and complex manufacturing processes are greatly reduced as compared to conventional synthetic methods. This is a great benefit for cost-effective translation to commercial production. The nanoparticles are found to be superparamagnetic and exhibit properties consistent for use in MRI. In addition, the dextran coating imparts the water solubility and biocompatibility necessary for in vivo utilization.

  19. Rapid microwave-assisted synthesis of dextran-coated iron oxide nanoparticles for magnetic resonance imaging

    International Nuclear Information System (INIS)

    Osborne, Elizabeth A; Atkins, Tonya M; Kauzlarich, Susan M; Gilbert, Dustin A; Liu Kai; Louie, Angelique Y

    2012-01-01

    Currently, magnetic iron oxide nanoparticles are the only nanosized magnetic resonance imaging (MRI) contrast agents approved for clinical use, yet commercial manufacturing of these agents has been limited or discontinued. Though there is still widespread demand for these particles both for clinical use and research, they are difficult to obtain commercially, and complicated syntheses make in-house preparation unfeasible for most biological research labs or clinics. To make commercial production viable and increase accessibility of these products, it is crucial to develop simple, rapid and reproducible preparations of biocompatible iron oxide nanoparticles. Here, we report a rapid, straightforward microwave-assisted synthesis of superparamagnetic dextran-coated iron oxide nanoparticles. The nanoparticles were produced in two hydrodynamic sizes with differing core morphologies by varying the synthetic method as either a two-step or single-step process. A striking benefit of these methods is the ability to obtain swift and consistent results without the necessity for air-, pH- or temperature-sensitive techniques; therefore, reaction times and complex manufacturing processes are greatly reduced as compared to conventional synthetic methods. This is a great benefit for cost-effective translation to commercial production. The nanoparticles are found to be superparamagnetic and exhibit properties consistent for use in MRI. In addition, the dextran coating imparts the water solubility and biocompatibility necessary for in vivo utilization. (paper)

  20. Ex situ integration of iron oxide nanoparticles onto the exfoliated expanded graphite flakes in water suspension

    Directory of Open Access Journals (Sweden)

    Jović Nataša

    2014-01-01

    Full Text Available Hybrid structures composed of exfoliated expanded graphite (EG and iron oxide nanocrystals have been produced by an ex situ process. The iron oxide nanoparticles coated with meso-2,3-dimercaptosuccinic acid (DMSA, or poly(acrylic acid (PAA were integrated onto the exfoliated EG flakes by mixing their aqueous suspensions at room temperature under support of 1-ethyl-3-(3-dimethylaminopropylcarbodiimide (EDC and N-hydroxysuccin-nimide (NHS. EG flakes have been used both, naked and functionalized with branched polyethylenimine (PEI. Complete integration of two constituents has been achieved and mainteined stable for more than 12 months. No preferential spatial distribution of anchoring sites for attachement of iron oxide nanoparticles has been observed, regardless EG flakes have been used naked or functionalized with PEI molecules. The structural and physico-chemical characteristics of the exfoliated expanded graphite and its hybrids nanostructures has been investigated by SEM, TEM, FTIR and Raman techniques. [Projekat Ministarstva nauke Republike Srbije, br. 45015

  1. Magnetic Iron Oxide Nanoparticles for Multimodal Imaging and Therapy of Cancer

    Directory of Open Access Journals (Sweden)

    In-Kyu Park

    2013-07-01

    Full Text Available Superparamagnetic iron oxide nanoparticles (SPION have emerged as an MRI contrast agent for tumor imaging due to their efficacy and safety. Their utility has been proven in clinical applications with a series of marketed SPION-based contrast agents. Extensive research has been performed to study various strategies that could improve SPION by tailoring the surface chemistry and by applying additional therapeutic functionality. Research into the dual-modal contrast uses of SPION has developed because these applications can save time and effort by reducing the number of imaging sessions. In addition to multimodal strategies, efforts have been made to develop multifunctional nanoparticles that carry both diagnostic and therapeutic cargos specifically for cancer. This review provides an overview of recent advances in multimodality imaging agents and focuses on iron oxide based nanoparticles and their theranostic applications for cancer. Furthermore, we discuss the physiochemical properties and compare different synthesis methods of SPION for the development of multimodal contrast agents.

  2. Surface modification of iron oxide nanoparticles and their conjuntion with water soluble polymers for biomedical application

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Thanh Huong; Lam Thi Kieu Giang; Nguyen Thanh Binh; Le Quoc Minh [Institute of Materials Science, Vietnam Academy of Science and Technology 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi (Viet Nam)], E-mail: nthuong@ims.vast.ac.vn

    2009-09-01

    Superparamagnetic iron oxide nanoparticles (SPION) coated with suitable bio-compatible substances have been used in biomedicine, particularly in magnetic resonance imaging (MRI), tissue engineering, and hyperthermia and drug delivery. In this study, we describe the synthesis of SPION and its surface modification for in-vitro experiments. The particle diameter and structure were estimated by FESEM, TEM, XRD analyses. The saturation magnetization was characterized. SPION with a mean size of 12 nm have been prepared under N{sub 2} atmosphere, with support of natural polymeric starch, by controlling chemical coprecipitation of magnetite phase from aqueous solutions containing suitable salts ratios of Fe{sup 2+} and Fe{sup 3+}. The surface of SPION-nanoparticles was treated with a coordinatable agent for higher dispersion ability in water and remaining the superparamagnetic behavior. The prepared iron oxide nanoparticles were coated with starch, dextran, PEG or MPEG to extend the application potential in the quite different engineering field of nano biomedicine.

  3. Determination of anisotropy constants of protein encapsulated iron oxide nanoparticles by electron magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Li Hongyan [Department of Physics, Montana State University, Bozeman, MT 59717 (United States); Center for Bio-Inspired Nanomaterials, Montana State University, Bozeman, MT 59717 (United States); Klem, Michael T.; Sebby, Karl B.; Singel, David J. [Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717 (United States); Center for Bio-Inspired Nanomaterials, Montana State University, Bozeman, MT 59717 (United States); Young, Mark [Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT 59717 (United States); Center for Bio-Inspired Nanomaterials, Montana State University, Bozeman, MT 59717 (United States); Douglas, Trevor [Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717 (United States); Center for Bio-Inspired Nanomaterials, Montana State University, Bozeman, MT 59717 (United States); Idzerda, Yves U. [Department of Physics, Montana State University, Bozeman, MT 59717 (United States); Center for Bio-Inspired Nanomaterials, Montana State University, Bozeman, MT 59717 (United States)], E-mail: Idzerda@montana.edu

    2009-02-15

    Angle-dependent electron magnetic resonance was performed on 4.9, 8.0, and 19 nm iron oxide nanoparticles encapsulated within protein capsids and suspended in water. Measurements were taken at liquid nitrogen temperature after cooling in a 1 T field to partially align the particles. The angle dependence of the shifts in the resonance field for the iron oxide nanoparticles (synthesized within Listeria-Dps, horse spleen ferritin, and cowpea chlorotic mottle virus) all show evidence of a uniaxial anisotropy. Using a Boltzmann distribution for the particles' easy-axis direction, we are able to use the resonance field shifts to extract a value for the anisotropy energy, showing that the anisotropy energy density increases with decreasing particle size. This suggests that surface anisotropy plays a significant role in magnetic nanoparticles of this size.

  4. Theoretical Modelling of Immobilization of Cadmium and Nickel in Soil Using Iron Nanoparticles

    Directory of Open Access Journals (Sweden)

    Vaidotas Danila

    2017-09-01

    Full Text Available Immobilization using zero valent using iron nanoparticles is a soil remediation technology that reduces concentrations of dissolved contaminants in soil solution. Immobilization of heavy metals in soil can be achieved through heavy metals adsorption and surface complexation reactions. These processes result in adsorption of heavy metals from solution phase and thus reducing their mobility in soil. Theoretical modelling of heavy metals, namely, cadmium and nickel, adsorption using zero valent iron nanoparticles was conducted using Visual MINTEQ. Adsorption of cadmium and nickel from soil solutions were modelled separately and when these metals were dissolved together. Results have showed that iron nanoparticles can be successfully applied as an effective adsorbent for cadmium and nickel removal from soil solution by producing insoluble compounds. After conducting the modelling of dependences of Cd+2 and Ni+2 ions adsorption on soil solution pH using iron nanoparticles, it was found that increasing pH of solution results in the increase of these ions adsorption. Adsorption of cadmium reached approximately 100% when pH ≥ 8.0, and adsorption of nickel reached approximately 100% when pH ≥ 7.0. During the modelling, it was found that adsorption of heavy metals Cd and Ni mostly occur, when one heavy metal ion is chemically adsorbed on two sorption sites. During the adsorption modelling, when Cd+2 and Ni+2 ions were dissolved together in acidic phase, it was found that adsorption is slightly lower than modelling adsorption of these metals separately. It was influenced by the competition of Cd+2 and Ni+2 ions for sorption sites on the surface of iron nanoparticles.

  5. Evaluation of tumoral enhancement by superparamagnetic iron oxide particles: comparative studies with ferumoxtran and anionic iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Brillet, P-Y.; Gazeau, F.; Luciani, A.; Bessoud, B.; Cuenod, C.-A.; Siauve, N.; Pons, J.-N.; Poupon, J.; Clement, O.

    2005-01-01

    This study was designed to compare tumor enhancement by superparamagnetic iron oxide particles, using anionic iron oxide nanoparticles (AP) and ferumoxtran. In vitro, relaxometry and media with increasing complexity were used to assess the changes in r2 relaxivity due to cellular internalization. In vivo, 26 mice with subcutaneously implanted tumors were imaged for 24 h after injection of particles to describe kinetics of enhancement using T1 spin echo, T2 spin echo, and T2 fast spin echo sequences. In vitro, the r2 relaxivity decreased over time (0-4 h) when AP were uptaken by cells. The loss of r2 relaxivity was less pronounced with long (Hahn Echo) than short (Carr-Purcell-Meiboom-Gill) echo time sequences. In vivo, our results with ferumoxtran showed an early T2 peak (1 h), suggesting intravascular particles and a second peak in T1 (12 h), suggesting intrainterstitial accumulation of particles. With AP, the late peak (24 h) suggested an intracellular accumulation of particles. In vitro, anionic iron oxide nanoparticles are suitable for cellular labeling due to a high cellular uptake. Conversely, in vivo, ferumoxtran is suitable for passive targeting of tumors due to a favorable biodistribution. (orig.)

  6. Lectin-functionalized magnetic iron oxide nanoparticles for reproductive improvement

    Science.gov (United States)

    Background: Semen ejaculates contain heterogeneous sperm populations that can jeopardize male fertility. Recent development of nanotechnology in physiological systems may have applications in reproductive biology. Here, we used magnetic nanoparticles as a novel strategy for sperm purification to imp...

  7. Effect of substrate interface on the magnetism of supported iron nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Balan, A. [Swiss Light Source, Paul Scherrer Institut (PSI), Villigen CH-5232 (Switzerland); Fraile Rodríguez, A. [Departament de Física Fonamental and Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08028 Barcelona (Spain); Vaz, C.A.F.; Kleibert, A.; Nolting, F. [Swiss Light Source, Paul Scherrer Institut (PSI), Villigen CH-5232 (Switzerland)

    2015-12-15

    In situ X-ray photo-emission electron microscopy is used to investigate the magnetic properties of iron nanoparticles deposited on different single crystalline substrates, including Si(001), Cu(001), W(110), and NiO(001). We find that, in our room temperature experiments, Fe nanoparticles deposited on Si(001) and Cu(001) show both superparamagnetic and magnetically stable (blocked) ferromagnetic states, while Fe nanoparticles deposited on W(110) and NiO(001) show only superparamagnetic behaviour. The dependence of the magnetic behaviour of the Fe nanoparticles on the contact surface is ascribed to the different interfacial bonding energies, higher for W and NiO, and to a possible relaxation of point defects within the core of the nanoparticles on these substrates, that have been suggested to stabilise the ferromagnetic state at room temperature when deposited on more inert surfaces such as Si and Cu. - Highlights: • In situ X-ray photo-emission electron microscopy study on iron nanoparticles. • Magnetically blocked particles are found on Si(001) and Cu(001). • Superparamagnetic particles are found on W(110) and Ni0(001). • The substrate dependent behavior is ascribed to the different bonding energies.

  8. Quantification of the internalization patterns of superparamagnetic iron oxide nanoparticles with opposite charge

    Directory of Open Access Journals (Sweden)

    Schweiger Christoph

    2012-07-01

    Full Text Available Abstract Time-resolved quantitative colocalization analysis is a method based on confocal fluorescence microscopy allowing for a sophisticated characterization of nanomaterials with respect to their intracellular trafficking. This technique was applied to relate the internalization patterns of nanoparticles i.e. superparamagnetic iron oxide nanoparticles with distinct physicochemical characteristics with their uptake mechanism, rate and intracellular fate. The physicochemical characterization of the nanoparticles showed particles of approximately the same size and shape as well as similar magnetic properties, only differing in charge due to different surface coatings. Incubation of the cells with both nanoparticles resulted in strong differences in the internalization rate and in the intracellular localization depending on the charge. Quantitative and qualitative analysis of nanoparticles-organelle colocalization experiments revealed that positively charged particles were found to enter the cells faster using different endocytotic pathways than their negative counterparts. Nevertheless, both nanoparticles species were finally enriched inside lysosomal structures and their efficiency in agarose phantom relaxometry experiments was very similar. This quantitative analysis demonstrates that charge is a key factor influencing the nanoparticle-cell interactions, specially their intracellular accumulation. Despite differences in their physicochemical properties and intracellular distribution, the efficiencies of both nanoparticles as MRI agents were not significantly different.

  9. Immunological effects of iron oxide nanoparticles and iron-based complex drug formulations: Therapeutic benefits, toxicity, mechanistic insights, and translational considerations.

    Science.gov (United States)

    Shah, Ankit; Dobrovolskaia, Marina A

    2018-04-01

    Nanotechnology offers several advantages for drug delivery. However, there is the need for addressing potential safety concerns regarding the adverse health effects of these unique materials. Some such effects may occur due to undesirable interactions between nanoparticles and the immune system, and they may include hypersensitivity reactions, immunosuppression, and immunostimulation. While strategies, models, and approaches for studying the immunological safety of various engineered nanoparticles, including metal oxides, have been covered in the current literature, little attention has been given to the interactions between iron oxide-based nanomaterials and various components of the immune system. Here we provide a comprehensive review of studies investigating the effects of iron oxides and iron-based nanoparticles on various types of immune cells, highlight current gaps in the understanding of the structure-activity relationships of these materials, and propose a framework for capturing their immunotoxicity to streamline comparative studies between various types of iron-based formulations. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Synthesis of binary iron-carbon nanoparticles by UV laser photolysis of Fe(CO)5 with various hydrocarbons

    Science.gov (United States)

    Eremin, A. V.; Gurentsov, E. V.; Musikhin, S. A.

    2016-10-01

    In this study the laser photolysis of the mixtures containing vapors of various hydrocarbons and iron pentacarbonyl was implemented to nanoparticle formation. The radiation source used for photo-dissociation of precursors was a pulsed Nd:Yag laser operated at a wavelength of 266 nm. Under UV radiation the molecules of Fe(CO)5 decomposed, forming atomic iron vapor and unsaturated carbonyls at well-known and readily controllable parameters. The subsequent condensation of supersaturated metal vapor resulted in small iron clusters and nanoparticles formation. The growth process of the nanoparticles was observed by a method of laser light extinction. Laser induced incandescence technique was applied for particle sizing during the process of their formation. Additionally nanoparticle samples were investigated by a transmission electron microscope. The particle size distribution was measured by statistical treatment of microphotographs. The elemental analysis by energy-dispersive x-ray spectroscopy and electron diffraction pattern gave the composition and structure of nanoparticles. The core-shell iron-carbon nanoparticles were synthesized by joint laser photolysis of iron pentacarbonyl with benzene and acetylene. The photolysis of the mixtures of toluene, butanol and methane with iron pentacarbonyl revealed in a pure iron particles formation which fast oxidized in air when were extracted out of the reactor.

  11. Magnetic composites based on hybrid spheres of aluminum oxide and superparamagnetic nanoparticles of iron oxides

    International Nuclear Information System (INIS)

    Braga, Tiago P.; Vasconcelos, Igor F.; Sasaki, Jose M.; Fabris, J.D.; Oliveira, Diana Q.L. de; Valentini, Antoninho

    2010-01-01

    Materials containing hybrid spheres of aluminum oxide and superparamagnetic nanoparticles of iron oxides were obtained from a chemical precursor prepared by admixing chitosan and iron and aluminum hydroxides. The oxides were first characterized with scanning electron microscopy, X-ray diffraction, and Moessbauer spectroscopy. Scanning electron microscopy micrographs showed the size distribution of the resulting spheres to be highly homogeneous. The occurrence of nano-composites containing aluminum oxides and iron oxides was confirmed from powder X-ray diffraction patterns; except for the sample with no aluminum, the superparamagnetic relaxation due to iron oxide particles were observed from Moessbauer spectra obtained at 298 and 110 K; the onset six line-spectrum collected at 20 K indicates a magnetic ordering related to the blocking relaxation effect for significant portion of small spheres in the sample with a molar ratio Al:Fe of 2:1.

  12. Iron phosphate nanoparticles for food fortification: Biological effects in rats and human cell lines.

    Science.gov (United States)

    von Moos, Lea M; Schneider, Mirjam; Hilty, Florentine M; Hilbe, Monika; Arnold, Myrtha; Ziegler, Nathalie; Mato, Diogo Sales; Winkler, Hans; Tarik, Mohamed; Ludwig, Christian; Naegeli, Hanspeter; Langhans, Wolfgang; Zimmermann, Michael B; Sturla, Shana J; Trantakis, Ioannis A

    2017-05-01

    Nanotechnology offers new opportunities for providing health benefits in foods. Food fortification with iron phosphate nanoparticles (FePO 4 NPs) is a promising new approach to reducing iron deficiency because FePO 4 NPs combine high bioavailability with superior sensory performance in difficult to fortify foods. However, their safety remains largely untested. We fed rats for 90 days diets containing FePO 4 NPs at doses at which iron sulfate (FeSO 4 ), a commonly used food fortificant, has been shown to induce adverse effects. Feeding did not result in signs of toxicity, including oxidative stress, organ damage, excess iron accumulation in organs or histological changes. These safety data were corroborated by evidence that NPs were taken up by human gastrointestinal cell lines without reducing cell viability or inducing oxidative stress. Our findings suggest FePO 4 NPs appear to be as safe for ingestion as FeSO 4 .

  13. Synthesis, characterization, and cytotoxicity of glutathione-PEG-iron oxide magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Paula S.; Santos, Marconi C. [Universidade Federal de São Paulo, UNIFESP, Exact and Earth Sciences Department (Brazil); Guzzi Cassago, Carolina Aparecida de [Universidade Estadual de Campinas, UNICAMP, Department of Biochemistry and Tissue Biology, Institute of Biology (Brazil); Bernardes, Juliana S. [National Nanotechnology Laboratory (LNNano), National Center for Energy and Materials (CNPEM) (Brazil); Jesus, Marcelo Bispo de [Universidade Estadual de Campinas, UNICAMP, Department of Biochemistry and Tissue Biology, Institute of Biology (Brazil); Seabra, Amedea B., E-mail: amedea.seabra@ufabc.edu.br [Universidade Federal de São Paulo, UNIFESP, Exact and Earth Sciences Department (Brazil)

    2016-12-15

    Recently, increasing interest is spent on the synthesis of superparamagnetic iron oxide nanoparticles, followed by their characterization and evaluation of cytotoxicity towards tumorigenic cell lines. In this work, magnetite (Fe{sub 3}O{sub 4}) nanoparticles were synthesized by the polyol method and coated with polyethylene glycol (PEG) and glutathione (GSH), leading to the formation of PEG-Fe{sub 3}O{sub 4} and GSH-PEG-Fe{sub 3}O{sub 4} nanoparticles. The nanoparticles were characterized by state-of-the-art techniques: dynamic light scattering (DLS), atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and superconducting quantum interference device (SQUID) magnetic measurements. PEG-Fe{sub 3}O{sub 4} and GSH-PEG-Fe{sub 3}O{sub 4} nanoparticles have crystallite sizes of 10 and 5 nm, respectively, indicating compression in crystalline lattice upon addition of GSH on the nanoparticle surface. Both nanoparticles presented superparamagnetic behavior at room temperature, and AFM images revealed the regular spherical shape of the nanomaterials and the absence of particle aggregation. The average hydrodynamic sizes of PEG-Fe{sub 3}O{sub 4} and GSH-PEG-Fe{sub 3}O{sub 4} nanoparticles were 69 ± 37 and 124 nm ± 75 nm, respectively. The cytotoxicity of both nanoparticles was screened towards human prostatic carcinoma cells (PC-3). The results demonstrated a decrease in PC-3 viability upon treatment with PEG-Fe{sub 3}O{sub 4} or GSH-PEG-Fe{sub 3}O{sub 4} nanoparticles in a concentration-dependent manner. However, the cytotoxicity was not time-dependent. Due to the superparamagnetic behavior of PEG-Fe{sub 3}O{sub 4} or GSH-PEG-Fe{sub 3}O{sub 4} nanoparticles, upon the application of an external magnetic field, those nanoparticles can be guided to the target site yielding local toxic effects to tumor cells with minimal side effects to normal tissues, highlighting the promising uses of iron oxide nanoparticles in

  14. Structural and morphological investigation of magnetic nanoparticles based on iron oxides for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Paula S. [Laboratorio Nacional de Luz Sincrotron (LNLS), Caixa Postal 6192, CEP 13083-970, Campinas-SP (Brazil)], E-mail: pferreira@lnls.br; Martins, Tatiana M. [Laboratorio Nacional de Luz Sincrotron (LNLS), Caixa Postal 6192, CEP 13083-970, Campinas-SP (Brazil); Instituto de Fisica Gleb Wataghin (IFGW), Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6165, CEP 13083-970, Campinas-SP (Brazil); D' Souza-Li, Lilia [Laboratorio de Endocrinologia Pediatrica da Faculdade de Ciencias Medicas (FCM), UNICAMP, Caixa Postal 6111, CEP 13083-970, Campinas-SP (Brazil); Li, Li M. [Departamento de Neurologia da FCM, UNICAMP, Caixa Postal 6111, CEP 13083-970, Campinas-SP (Brazil); Metze, Konradin; Adam, Randall L. [Grupo interdisciplinar ' Patologia Analitica Celular' , Departamento de Anatomia Patologica da FCM, UNICAMP, Caixa Postal 6111, CEP 13083-970, Campinas-SP (Brazil); Knobel, Marcelo [Instituto de Fisica Gleb Wataghin (IFGW), Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6165, CEP 13083-970, Campinas-SP (Brazil); Zanchet, Daniela [Laboratorio Nacional de Luz Sincrotron (LNLS), Caixa Postal 6192, CEP 13083-970, Campinas-SP (Brazil)

    2008-05-01

    The present work reports the synthesis, characterization and properties of magnetic iron oxide nanoparticles for biomedical applications, correlating the nanoscale tunabilities in terms of size, structure, and magnetism. Magnetic nanoparticles in different conditions were prepared through thermal decomposition of Fe(acac){sub 3} in the presence of 1,2 hexadecanodiol (reducing agent) and oleic acid and oleylamine (ligands) in a hot organic solvent. The 2,3-dimercaptosuccinic acid (DMSA) was exchanged onto the nanocrystal surface making the particles stable in water. Nanoparticles were characterized by X-ray diffraction (XRD) measurements, small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Preliminary tests of incorporation of these nanoparticles in cells and their magnetic resonance image (MRI) were also carried out. The magnetization characterizations were made by isothermal magnetic measurements.

  15. Modelling irradiation by EM waves of multifunctionalized iron oxide nanoparticles and subsequent drug release

    International Nuclear Information System (INIS)

    Wang, Feng; Calvayrac, Florent; Montembault, Véronique; Fontaine, Laurent

    2015-01-01

    Thermal transport in the environment close to the periphery of the nanoparticle, from a few angstroms to less than a nanometer scale, is becoming increasingly important with the advent of several biomedical applications of multifunctional magnetic nanoparticles, including drug delivery, magnetic resonance imaging, and hyperthermia therapy. We present a multiscale and multiphysics model of the irradiation by electromagnetic waves of radiofrequency of iron oxide nanoparticles functionalized by drug-releasing polymers used as new multifunctional therapeutic compounds against tumors. We compute ab initio the thermal conductivity of the polymer chains as a function of the length, model the unfolding of the polymer after heat transfer from the nanoparticle by molecular mechanics, and develop a multiscale thermodynamic and heat transfer model including the surrounding medium (water) in order to model the drug release. (paper)

  16. Structural and morphological investigation of magnetic nanoparticles based on iron oxides for biomedical applications

    International Nuclear Information System (INIS)

    Haddad, Paula S.; Martins, Tatiana M.; D'Souza-Li, Lilia; Li, Li M.; Metze, Konradin; Adam, Randall L.; Knobel, Marcelo; Zanchet, Daniela

    2008-01-01

    The present work reports the synthesis, characterization and properties of magnetic iron oxide nanoparticles for biomedical applications, correlating the nanoscale tunabilities in terms of size, structure, and magnetism. Magnetic nanoparticles in different conditions were prepared through thermal decomposition of Fe(acac) 3 in the presence of 1,2 hexadecanodiol (reducing agent) and oleic acid and oleylamine (ligands) in a hot organic solvent. The 2,3-dimercaptosuccinic acid (DMSA) was exchanged onto the nanocrystal surface making the particles stable in water. Nanoparticles were characterized by X-ray diffraction (XRD) measurements, small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Preliminary tests of incorporation of these nanoparticles in cells and their magnetic resonance image (MRI) were also carried out. The magnetization characterizations were made by isothermal magnetic measurements

  17. Integrity of 111In-radiolabeled superparamagnetic iron oxide nanoparticles in the mouse

    International Nuclear Information System (INIS)

    Wang, Haotian; Kumar, Rajiv; Nagesha, Dattatri; Duclos, Richard I.; Sridhar, Srinivas; Gatley, Samuel J.

    2015-01-01

    Introduction: Iron-oxide nanoparticles can act as contrast agents in magnetic resonance imaging (MRI), while radiolabeling the same platform with nuclear medicine isotopes allows imaging with positron emission tomography (PET) or single-photon emission computed tomography (SPECT), modalities that offer better quantification. For successful translation of these multifunctional imaging platforms to clinical use, it is imperative to evaluate the degree to which the association between radioactive label and iron oxide core remains intact in vivo. Methods: We prepared iron oxide nanoparticles stabilized by oleic acid and phospholipids which were further radiolabeled with 59 Fe, 14 C-oleic acid, and 111 In. Results: Mouse biodistributions showed 111 In preferentially localized in reticuloendothelial organs, liver, spleen and bone. However, there were greater levels of 59 Fe than 111 In in liver and spleen, but lower levels of 14 C. Conclusions: While there is some degree of dissociation between the 111 In labeled component of the nanoparticle and the iron oxide core, there is extensive dissociation of the oleic acid component

  18. Degradation of bis- p -nitrophenyl phosphate using zero-valent iron nanoparticles

    International Nuclear Information System (INIS)

    Valle-Orta, Maiby; Guerrero, Rubén Saldivar; Díaz, David; Dubé, Inti Zumeta; Quiñonez, José Luis Ortiz

    2017-01-01

    Phosphate esters are employed in some agrochemical formulations and have long life time in the Environment. They are neurotoxic to mammals and it is very difficult to hydrolyze them. It is easy to find papers in the literature dealing with transition metal complexes used in the hydrolysis processes of organophosphorous compounds. However, there are few reports related with degradation of phosphate esters with inorganic nanoparticles. In this work bis-4-nitrophenyl phosphate (BNPP) was used as an agrochemical agent model. The BNPP interaction with zero-valent iron nanoparticles (ZVI NPs), in aqueous media, was searched. The concentration of BNPP was 1000 times higher than the ZVI NPs concentration. The average size of the used iron nanoparticles was 10.2 ± 3.2 nm. The BNPP degradation process was monitored by means of UV-visible method. Initially, the BNPP hydrolysis happens through the P-O bonds breaking-off under the action of the ZVI NPs. Subsequently, the nitro groups were reduced to amine groups. The overall process takes place in 10 minutes. The reaction products were identified employing standard substances in adequate concentrations. The iron by-products were isolated and characterized by X-RD. These iron derivatives were identified as magnetite (Fe 3 O 4 ) and/or maghemite (γ-Fe 2 O 3 ) and lepidocrocite (γ-FeOOH). A suggested BNPP degradation mechanism will be discussed. (paper)

  19. Iron Oxide Nanoparticles Employed as Seeds for the Induction of Microcrystalline Diamond Synthesis

    Directory of Open Access Journals (Sweden)

    Resto Oscar

    2008-01-01

    Full Text Available AbstractIron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. X-ray diffraction, visible, and ultraviolet Raman Spectroscopy, energy-filtered transmission electron microscopy , electron energy-loss spectroscopy, and X-ray photoelectron spectroscopy (XPS were employed to study the carbon bonding nature of the films and to analyze the carbon clustering around the seed nanoparticles leading to diamond synthesis. The results indicate that iron oxide nanoparticles lose the O atoms, becoming thus active C traps that induce the formation of a dense region of trigonally and tetrahedrally bonded carbon around them with the ensuing precipitation of diamond-type bonds that develop into microcrystalline diamond films under chemical vapor deposition conditions. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

  20. Evaluation of synthesized iron oxide nanoparticles in removal of copper ions from aqueous solution

    Directory of Open Access Journals (Sweden)

    MH Salmani

    2016-11-01

    Full Text Available Abstract Introduction: water source pollutant, result of direct releasing of metal ions to environment, is one of the most important problems in the world. In this study, efficiency of synthesized iron oxide nanoparticles in presence of extract tangerine Peel was investigated for removal of copper ions in the solution. Methods: Iron oxide nanoparticles were prepared by co-perception method using Tangerine Peel extract. The Tangerine Peel extract used to decrease of nanoparticle size and to prevent of particles coagulation. The effect of different parameter includes initial copper concentration, adsorbent dose, contact time and solution pH was investigated on removal of copper. The experimental data were fitted to Langmuir and Freundlich isotherm models. Results: The results showed that the removal efficiency was increased by increasing of pH and decreased from 88% to 81% by increasing of initial copper concentration from 5 mg/l to 10 mg/l. The most removal percent was 92% when copper concentration was 5 mg/l and adsorbent doze was 0.6 g in 100 ml suspension. Conclusion: The results showed the removal efficiency is depended on to pH. The increase of copper concentration decreased the removal efficiency. Adsorption experimental data were in good accordance with Langmuir isotherm model. The synthesized iron oxide nanoparticles with extract Tangerine Peel is a good adsorbent for removing of heavy metals from aqueous solution.

  1. Biosynthesis, Characterization, and Biological Activities of Iron Nanoparticles using Sesamum indicum Seeds Extract

    Science.gov (United States)

    Bano, Farah; Baber, Muhammad; Ali, Amjad; Shah, Ziaullah; Muhammad, Syed Aun

    2017-01-01

    Background: Iron nanoparticles (FeNPs) have got many biomedical and health applications because of biocompatible and nontoxic nature to humans. Objective: To synthesize the FeNPs using natural sources. Materials and Methods: In this study, simple and economical procedure was adopted for FeNPs synthesis. Sesame seeds were processed to obtain seed extract as a biological material for FeNPs production. FeNPs were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopic. Results: The average diameter of these FeNPs was 99 nm. These nanoparticles showed significant anti-typhoid activity (30 mm zone of inhibition) as compared to ciprofloxacin (32 mm) as standard. Furthermore, in vitro alpha-amylase inhibitory assay also showed moderate antidiabetic activity with more than 50% inhibition. Conclusion: This study would be helpful in understanding of nanoparticles synthesis from natural sources and ultimately will be used as potential alternative therapeutic agents. SUMMARY Iron nanoparticles (FeNPs) were synthesized by Sesamum indicum seedsFeNPs were characterized by scanning electron microscope with average diameter of 99 nmThese FeNPs are effective against Salmonella typhi, a causative agent of typhoidThese FeNPs can be used as antidiabetic agent. Abbreviations used: FeNPs: Iron Nano Particles; SEM: Scanning Electron Microscopy; MIC: Minimum Inhibitory Concentration; S. indicum: Sesamum Indicum. PMID:28479723

  2. Biosynthesis, Characterization, and Biological Activities of Iron Nanoparticles usingSesamum indicumSeeds Extract.

    Science.gov (United States)

    Bano, Farah; Baber, Muhammad; Ali, Amjad; Shah, Ziaullah; Muhammad, Syed Aun

    2017-01-01

    Iron nanoparticles (FeNPs) have got many biomedical and health applications because of biocompatible and nontoxic nature to humans. To synthesize the FeNPs using natural sources. In this study, simple and economical procedure was adopted for FeNPs synthesis. Sesame seeds were processed to obtain seed extract as a biological material for FeNPs production. FeNPs were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopic. The average diameter of these FeNPs was 99 nm. These nanoparticles showed significant anti-typhoid activity (30 mm zone of inhibition) as compared to ciprofloxacin (32 mm) as standard. Furthermore, in vitro alpha-amylase inhibitory assay also showed moderate antidiabetic activity with more than 50% inhibition. This study would be helpful in understanding of nanoparticles synthesis from natural sources and ultimately will be used as potential alternative therapeutic agents. Iron nanoparticles (FeNPs) were synthesized by Sesamum indicum seedsFeNPs were characterized by scanning electron microscope with average diameter of 99 nmThese FeNPs are effective against Salmonella typhi , a causative agent of typhoidThese FeNPs can be used as antidiabetic agent. Abbreviations used: FeNPs: Iron Nano Particles; SEM: Scanning Electron Microscopy; MIC: Minimum Inhibitory Concentration; S. indicum : Sesamum Indicum .

  3. Adsorbent 2D and 3D carbon matrices with protected magnetic iron nanoparticles

    Science.gov (United States)

    Carreño, N. L. V.; Escote, M. T.; Valentini, A.; McCafferty, L.; Stolojan, V.; Beliatis, M.; Mills, C. A.; Rhodes, R.; Smith, C. T. G.; Silva, S. R. P.

    2015-10-01

    We report on the synthesis of two and three dimensional carbonaceous sponges produced directly from graphene oxide (GO) into which functionalized iron nanoparticles can be introduced to render it magnetic. This simple, low cost procedure, wherein an iron polymeric resin precursor is introduced into the carbon framework, results in carbon-based materials with specific surface areas of the order of 93 and 66 m2 g-1, compared to approx. 4 m2 g-1 for graphite, decorated with ferromagnetic iron nanoparticles giving coercivity fields postulated to be 216 and 98 Oe, values typical for ferrite magnets, for 3.2 and 13.5 wt% Fe respectively. The strongly magnetic iron nanoparticles are robustly anchored to the GO sheets by a layer of residual graphite, on the order of 5 nm, formed during the pyrolysis of the precursor material. The applicability of the carbon sponges is demonstrated in their ability to absorb, store and subsequently elute an organic dye, Rhodamine B, from water as required. It is possible to regenerate the carbon-iron hybrid material after adsorption by eluting the dye with a solvent to which it has a high affinity, such as ethanol. The use of a carbon framework opens the hybrid materials to further chemical functionalization, for enhanced chemical uptake of contaminants, or co-decoration with, for example, silver nanoparticles for bactericidal properties. Such analytical properties, combined with the material's magnetic character, offer solutions for environmental decontamination at land and sea, wastewater purification, solvent extraction, and for the concentration of dilute species.

  4. The formation of magnetic carboxymethyl-dextrane-coated iron-oxide nanoparticles using precipitation from an aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Makovec, Darko [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Gyergyek, Sašo, E-mail: saso.gyergyek@ijs.si [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Primc, Darinka [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Plantan, Ivan [Lek Pharmaceuticals d.d., Mengeš (Slovenia)

    2015-03-01

    The formation of spinel iron-oxide nanoparticles during the co-precipitation of Fe{sup 3+}/Fe{sup 2+} ions from an aqueous solution in the presence of carboxymethyldextrane (CMD) was studied. To follow the formation of the nanoparticles, a mixture of the Fe ions, CMD and ammonia was heated to different temperatures, while the samples were taken, quenched in liquid nitrogen, freeze-dried and characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD) and magnetometry. The CMD plays a role in the reactions of the Fe ions' precipitation by partially immobilizing the Fe{sup 3+} ions into a complex. At room temperature, the amorphous material is precipitated. Then, above approximately 30 °C, the spinel nanoparticles form inside the amorphous matrix, and at approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles. The CMD bonded to the nanoparticles' surfaces hinders the mass transport and thus prevents their growth. - Highlights: • The carboxymethyl-dextrane coated iron-oxide nanoparticles were synthesized. • The carboxymethyl-dextrane significantly modifies formation of the spinel nanoparticles. • The spinel nanoparticles are formed inside the amorphous matrix. • At approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles.

  5. Characterization and Functionalization of Iron-Oxide Nanoparticles for Use as Potential Agents for Cancer Thermotherapy

    Science.gov (United States)

    O'Reilly, Nora

    This thesis presents experimental studies of iron oxide nanoparticle synthesis, functionalization, and intracellular hyperthermal effects on murine macrophages as a model in vitro system. Colloidal suspensions of magnetic nanoparticles (MNPs) are of particular interest in Magnetic Fluid Hyperthermia (MFH). Iron oxide nanoparticles (IONPs) have garnered great interest as economical, biocompatible hyperthermia agents due to their superparamagnetic activity. Here we seek to optimize the synthetic reproducibility and in vitro utilization of IONPs for application in MFH. We compared aqueous synthetic protocols and various protective coating techniques using various analytical techniques and in vitro assays to assess the biocompatibility and feasibility of the various preparations of nanoparticles. Using a co-precipitation of iron salts methodology, iron oxide nanoparticles (IONPs) with an average diameter of 6-8nm were synthesized and stabilized with carboxylates. By performing calorimetry measurements in an oscillating magnetic field (OMF) with a frequency of 500 kHz and field strength of 0.008Tesla the superparamagnetic behavior of these particles was confirmed. To further investigate these IONPs in a biological application, citric acid-stabilized particles, in conjunction with heat generated by these IONPs when exposed to an OMF, were assessed to determine their effects on cell viability in a RAW 267.4 murine macrophage model system. Our results show that 91.5-97% of cells that have ingested IONPs die follow exposure to an OMF. Importantly, neither the IONPs (at applicable concentrations) nor the OMF show cytotoxic effects. These particular particles have promising preliminary results as hyperthermic agents in both the current literature and simple, proof-of-concept experiments in our laboratory setting. We present experimental results for the synthesis, characterization, and utilization of iron oxide nanoparticles in MFH. Our results show that while IONPs have

  6. Uptake of dimercaptosuccinate-coated magnetic iron oxide nanoparticles by cultured brain astrocytes

    International Nuclear Information System (INIS)

    Geppert, Mark; Hohnholt, Michaela C; Dringen, Ralf; Thiel, Karsten; Grunwald, Ingo; Nuernberger, Sylvia; Rezwan, Kurosch

    2011-01-01

    Magnetic iron oxide nanoparticles (Fe-NP) are currently considered for various diagnostic and therapeutic applications in the brain. However, little is known on the accumulation and biocompatibility of such particles in brain cells. We have synthesized and characterized dimercaptosuccinic acid (DMSA) coated Fe-NP and have investigated their uptake by cultured brain astrocytes. DMSA-coated Fe-NP that were dispersed in physiological medium had an average hydrodynamic diameter of about 60 nm. Incubation of cultured astrocytes with these Fe-NP caused a time- and concentration-dependent accumulation of cellular iron, but did not lead within 6 h to any cell toxicity. After 4 h of incubation with 100-4000 μM iron supplied as Fe-NP, the cellular iron content reached levels between 200 and 2000 nmol mg -1 protein. The cellular iron content after exposure of astrocytes to Fe-NP at 4 deg. C was drastically lowered compared to cells that had been incubated at 37 deg. C. Electron microscopy revealed the presence of Fe-NP-containing vesicles in cells that were incubated with Fe-NP at 37 deg. C, but not in cells exposed to the nanoparticles at 4 deg. C. These data demonstrate that cultured astrocytes efficiently take up DMSA-coated Fe-NP in a process that appears to be saturable and strongly depends on the incubation temperature.

  7. Synthesis and characterization of zero-valent iron nanoparticles supported on SBA-15

    Directory of Open Access Journals (Sweden)

    Felipe Sombra dos Santos

    2017-04-01

    Full Text Available This paper aims to synthesize zero-valent iron nanoparticles (nZVI supported on SBA-15 nanosilica. The nanosilica generate in the system by polymer reaction with hydrochloric acid under controlled temperature. After, the iron nanomaterial was obtained by sodium borohydride reduction as described in this work. Afterward the synthesis of the nanoparticles contained iron supported on silica SBA-15, the material was characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, zeta potential and X-ray fluorescence spectroscopy. The results indicated that nanomaterial obtained was in nanometric scale, by TEM results, and showing characteristic peaks at EDS results, with 11.9% iron and 14.0% silicon content, respectively, and containing 73.0% and 27.0% of their respective oxides through X-ray fluorescence spectroscopy. The isoelectric potential of the sample was around 2.0, close to the value reported for silica, due to the higher percentage of silica in the sample when compared to iron. The obtained material can be used, for some cases, as an possible alternative, to the Fenton reaction for the degradation of xenobiotic compounds or other applications in the groundwater and wastewater treatments.

  8. Synthesis of iron oxide nanoparticles of narrow size distribution on ...

    Indian Academy of Sciences (India)

    WINTEC

    Interaction between iron (II) sulfate and template has been carried out in aqueous phase, followed by the selective and controlled removal of the template to achieve narrow distribution of ... templates like aluminium oxide, carbon nanotubes, sur- factants, polymer fibres and egg shell membranes have been employed.

  9. Polymer Films with Ion-Synthesized Cobalt and Iron Nanoparticles

    DEFF Research Database (Denmark)

    Popok, Vladimir

    2014-01-01

    The current paper presents an overview and analysis of data obtained on a few sets of polymer samples implanted by iron and cobalt. The low-energy (40 keV) implantations were carried out into polyimide and polyethyleneterephthalate with fluences between 2.5x10e16-1.5x10e17 cm-2. The samples were...

  10. Self-orderding of iron oxide nanoparticles covered by graphene

    Czech Academy of Sciences Publication Activity Database

    Valeš, Václav; Vejpravová, Jana; Pacáková, Barbara; Holý, V.; Bernstorff, S.; Kalbáč, Martin

    2014-01-01

    Roč. 251, č. 12 (2014), s. 2499-2504 ISSN 0370-1972 R&D Projects: GA MŠk LL1301; GA ČR GAP204/10/1677 Institutional support: RVO:61388955 ; RVO:68378271 Keywords : GISAXS * graphene * iron oxide Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.489, year: 2014

  11. Tuning dipolar magnetic interactions by controlling individual silica coating of iron oxide nanoparticles

    Science.gov (United States)

    Rivas Rojas, P. C.; Tancredi, P.; Moscoso Londoño, O.; Knobel, M.; Socolovsky, L. M.

    2018-04-01

    Single and fixed size core, core-shell nanoparticles of iron oxides coated with a silica layer of tunable thickness were prepared by chemical routes, aiming to generate a frame of study of magnetic nanoparticles with controlled dipolar interactions. The batch of iron oxides nanoparticles of 4.5 nm radii, were employed as cores for all the coated samples. The latter was obtained via thermal decomposition of organic precursors, resulting on nanoparticles covered with an organic layer that was subsequently used to promote the ligand exchange in the inverse microemulsion process, employed to coat each nanoparticle with silica. The amount of precursor and times of reaction was varied to obtain different silica shell thicknesses, ranging from 0.5 nm to 19 nm. The formation of the desired structures was corroborated by TEM and SAXS measurements, the core single-phase spinel structure was confirmed by XRD, and superparamagnetic features with gradual change related to dipolar interaction effects were obtained by the study of the applied field and temperature dependence of the magnetization. To illustrate that dipolar interactions are consistently controlled, the main magnetic properties are presented and analyzed as a function of center to center minimum distance between the magnetic cores.

  12. Microwave-assisted synthesis of iron oxide nanoparticles in biocompatible organic environment

    Directory of Open Access Journals (Sweden)

    E. Aivazoglou

    2018-04-01

    Full Text Available The development of magnetite and maghemite particles in uniform nanometer size has triggered the interest of the research community due to their many interesting properties leading to a wide range of applications, such as catalysis, nanomedicine-nanobiology and other engineering applications. In this study, a simple, time-saving and low energy-consuming, microwave-assisted synthesis of iron oxide nanoparticles, is presented. The nanoparticles were prepared by microwave-assisted synthesis using polyethylene glycol (PEG or PEG and β-cyclodextrin (β-CD/water solutions of chloride salts of iron in the presence of ammonia solution. The prepared nano-powders were characterized using X-Ray Diffraction (XRD, Transition Electron Microscopy (TEM, Fourier-transform Infrared Spectroscopy (FTIR, Raman Spectroscopy, Vibrating Sample Magnetometer (VSM, X-Ray Photoelectron Spectroscopy (XPS and Thermal analysis (TG/DSC. The produced nanoparticles are crystallized mostly in the magnetite and maghemite lattice exhibiting very similar shape and size, with indications of partial PEG coating. Heating time, microwave power and presence of PEG, are the key factors shaping the size properties of nanoparticles. The average size of particles ranges from 10.3 to 19.2 nm. The nanoparticles exhibit a faceted morphology, with zero contamination levels. The magnetic measurements indicate that the powders are soft magnetic materials with negligible coercivity and remanence, illustrating super-paramagnetic behavior.

  13. Microwave-assisted synthesis of iron oxide nanoparticles in biocompatible organic environment

    Science.gov (United States)

    Aivazoglou, E.; Metaxa, E.; Hristoforou, E.

    2018-04-01

    The development of magnetite and maghemite particles in uniform nanometer size has triggered the interest of the research community due to their many interesting properties leading to a wide range of applications, such as catalysis, nanomedicine-nanobiology and other engineering applications. In this study, a simple, time-saving and low energy-consuming, microwave-assisted synthesis of iron oxide nanoparticles, is presented. The nanoparticles were prepared by microwave-assisted synthesis using polyethylene glycol (PEG) or PEG and β-cyclodextrin (β-CD)/water solutions of chloride salts of iron in the presence of ammonia solution. The prepared nano-powders were characterized using X-Ray Diffraction (XRD), Transition Electron Microscopy (TEM), Fourier-transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, Vibrating Sample Magnetometer (VSM), X-Ray Photoelectron Spectroscopy (XPS) and Thermal analysis (TG/DSC). The produced nanoparticles are crystallized mostly in the magnetite and maghemite lattice exhibiting very similar shape and size, with indications of partial PEG coating. Heating time, microwave power and presence of PEG, are the key factors shaping the size properties of nanoparticles. The average size of particles ranges from 10.3 to 19.2 nm. The nanoparticles exhibit a faceted morphology, with zero contamination levels. The magnetic measurements indicate that the powders are soft magnetic materials with negligible coercivity and remanence, illustrating super-paramagnetic behavior.

  14. Toxicity, toxicokinetics and biodistribution of dextran stabilized Iron oxide Nanoparticles for biomedical applications.

    Science.gov (United States)

    Remya, N S; Syama, S; Sabareeswaran, A; Mohanan, P V

    2016-09-10

    Advancement in the field of nanoscience and technology has alarmingly raised the call for comprehending the potential health effects caused by deliberate or unintentional exposure to nanoparticles. Iron oxide magnetic nanoparticles have an increasing number of biomedical applications and hence a complete toxicological profile of the nanomaterial is therefore a mandatory requirement prior to its intended usage to ensure safety and to minimize potential health hazards upon its exposure. The present study elucidates the toxicity of in house synthesized Dextran stabilized iron oxide nanoparticles (DINP) in a regulatory perspective through various routes of exposure, its associated molecular, immune, genotoxic, carcinogenic effects and bio distribution profile. Synthesized ferrite nanomaterials were successfully coated with dextran (nanoparticles with dextran helps in improvising particle stability in biological environments. The nanoparticles do not seem to induce oxidative stress mediated toxicological effects, nor altered physiological process or behavior changes or visible pathological lesions. Furthermore no anticipated health hazards are likely to be associated with the use of DINP and could be concluded that the synthesized DINP is nontoxic/safe to be used for biomedical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Cobalt-promoted Iron Oxide Nanoparticles for the Selective Oxidative Dehydrogenation of Cyclohexane

    Science.gov (United States)

    Rutter, Matthew

    Recent work has shown that both cobalt and iron oxide nanoparticles are active for the oxidative dehydrogenation (ODH) of cyclohexane to benzene, the former more active than the latter. Further study has shown that the addition of gold species as a minority component into iron oxide nanocrystals increases the selectivity of the reaction to benzene. Since a primary motivation for this work is the addition of catalysts in jet fuels to facilitate the dehydrogenation and cracking reactions preceding their combustion, a low-cost, sacrificial catalyst is sought after. In this application, catalyst nanoparticles suspended in the fuel stream will dehydrogenate cyclic alkanes (cyclohexane) to their aromatic counterparts (benzene). Alkenes and aromatics have a much higher rate of combustion, which decreases the amount of uncombusted fuel in the exhaust, thereby increasing performance. As these catalysts are not recyclable, there is significant impetus to substitute cheaper base metals for expensive noble metals. In this work, iron oxide nanoparticles are doped with varying levels of cobalt to examine the effect of cobalt content and oxidation state on the selectivity and activity of the iron oxide for the oxidative dehydrogenation of cyclohexane, used as a model cyclic alkane in jet fuel. We have shown previously that small (˜5nm) cobalt oxide nanoparticles favor the production of benzene over the partial dehydrogenation products cyclohexene and cyclohexadiene, or the complete oxidation product carbon dioxide. It is the aim of this work to examine the surface of these cobalt-iron oxide nanoparticles to determine the conditions most favorable for this selective oxidative dehydrogenation. Cobalt-doped iron nanoparticles were prepared by a surfactant-free hydrothermal co-precipitation technique that enabled a high degree of composition control and size control. These samples were characterized via Transmission Electron Microscopy (TEM), powder X-Ray Diffraction (XRD), X

  16. Single step synthesis, characterization and applications of curcumin functionalized iron oxide magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Rohit; Gupta, Prachi; Dziubla, Thomas; Hilt, J. Zach, E-mail: zach.hilt@uky.edu

    2016-10-01

    Magnetic iron oxide nanoparticles have been well known for their applications in magnetic resonance imaging (MRI), hyperthermia, targeted drug delivery, etc. The surface modification of these magnetic nanoparticles has been explored extensively to achieve functionalized materials with potential application in biomedical, environmental and catalysis field. Herein, we report a novel and versatile single step methodology for developing curcumin functionalized magnetic Fe{sub 3}O{sub 4} nanoparticles without any additional linkers, using a simple coprecipitation technique. The magnetic nanoparticles (MNPs) were characterized using transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy and thermogravimetric analysis. The developed MNPs were employed in a cellular application for protection against an inflammatory agent, a polychlorinated biphenyl (PCB) molecule. - Graphical abstract: Novel single step curcumin coated magnetic Fe{sub 3}O{sub 4} nanoparticles without any additional linkers for medical, environmental, and other applications. Display Omitted - Highlights: • A novel and versatile single step methodology for developing curcumin functionalized magnetic Fe{sub 3}O{sub 4} nanoparticles is reported. • The magnetic nanoparticles (MNPs) were characterized using TEM, XRD, FTIR and TGA. • The developed MNPs were employed in a cellular application for protection against an inflammatory agent, a polychlorinated biphenyl (PCB).

  17. Toxicity of iron oxide nanoparticles to grass litter decomposition in a sandy soil

    Science.gov (United States)

    Rashid, Muhammad Imtiaz; Shahzad, Tanvir; Shahid, Muhammad; Imran, Muhammad; Dhavamani, Jeyakumar; Ismail, Iqbal M. I.; Basahi, Jalal M.; Almeelbi, Talal

    2017-02-01

    We examined time-dependent effect of iron oxide nanoparticles (IONPs) at a rate of 2000 mg kg-1 soil on Cynodon dactylon litter (3 g kg-1) decomposition in an arid sandy soil. Overall, heterotrophic cultivable bacterial and fungal colonies, and microbial biomass carbon were significantly decreased in litter-amended soil by the application of nanoparticles after 90 and 180 days of incubation. Time dependent effect of nanoparticles was significant for microbial biomass in litter-amended soil where nanoparticles decreased this variable from 27% after 90 days to 49% after 180 days. IONPs decreased CO2 emission by 28 and 30% from litter-amended soil after 90 and 180 days, respectively. These observations indicated that time-dependent effect was not significant on grass-litter carbon mineralization efficiency. Alternatively, nanoparticles application significantly reduced mineral nitrogen content in litter-amended soil in both time intervals. Therefore, nitrogen mineralization efficiency was decreased to 60% after 180 days compared to that after 90 days in nanoparticles grass-litter amended soil. These effects can be explained by the presence of labile Fe in microbial biomass after 180 days in nanoparticles amendment. Hence, our results suggest that toxicity of IONPs to soil functioning should consider before recommending their use in agro-ecosystems.

  18. The influence of magnetic and physiological behaviour on the effectiveness of iron oxide nanoparticles for hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, C L; Lau, J W [Materials Science and Engineering Laboratory, NIST, Gaithersburg, MD 20899-8552 (United States); Jackson, A J; Borchers, J A [NIST Center for Neutron Research, Gaithersburg, MD 20899-6102 (United States); Ivkov, R; Foreman, A R [Triton BioSystems, Inc., Chelmsford, MA 01824 (United States); Hoopes, P J; Strawbridge, R; Pierce, Z [Dartmouth College, Hanover, NH 03755 (United States); Goerntiz, E [Fraunhofer Institut Angewandte Polymerforschung, 14476 Potsdam-Golm (Germany); Gruettner, C [Micromod Partikeltechnologie GmbH, 18119 Rostock-Warnemuende (Germany)

    2008-07-07

    Magnetic nanoparticles are being developed for a wide range of biomedical applications. In particular, hyperthermia involves heating the magnetic nanoparticles through exposure to an alternating magnetic field. These materials offer the potential to selectively treat cancer by heating cancer tissue locally and at the cellular level. This may be a successful method if there are enough particles in a tumor possessing a sufficiently high specific absorption rate (SAR) to deposit heat quickly while minimizing thermal damage to surrounding tissue. High SAR magnetic nanoparticles have been developed and used in mouse models of cancer. The magnetic nanoparticles comprise iron oxide magnetic cores (mean core diameter of 50 nm) surrounded by a dextran layer shell for colloidal stability. In comparing two similar systems, the saturation magnetization is found to play a crucial role in determining the SAR, but is not the only factor of importance. (A difference in saturation magnetization of a factor of 1.5 yields a difference in SAR of a factor of 2.5 at 1080 Oe and 150 kHz.) Variations in the interactions due to differences in the dextran layer, as determined through neutron scattering, also play a role in the SAR. Once these nanoparticles are introduced into the tumor, their efficacy, with respect to tumor growth, is determined by the location of the nanoparticles within or near the tumor cells and the association of the nanoparticles with the delivered alternating magnetic field (AMF). This association (nanoparticle SAR and AMF) determines the amount of heat generated. In our setting, the heat generated and the time of heating (thermal dose) provides a tumor gross treatment response which correlates closely with that of conventional (non-nanoparticle) hyperthermia. This being said, it appears specific aspects of the nanoparticle hyperthermia cytopathology mechanism may be very different from that observed in conventional cancer treatment hyperthermia.

  19. The use of ultrasmall iron(0) nanoparticles as catalysts for the selective hydrogenation of unsaturated C-C bonds.

    Science.gov (United States)

    Kelsen, Vinciane; Wendt, Bianca; Werkmeister, Svenja; Junge, Kathrin; Beller, Matthias; Chaudret, Bruno

    2013-04-28

    The performance of well-defined ultrasmall iron(0) nanoparticles (NPs) as catalysts for the selective hydrogenation of unsaturated C-C and C=X bonds is reported. Monodisperse iron nanoparticles of about 2 nm size are synthesized by the decomposition of {Fe(N[Si(CH3)3]2)2}2 under dihydrogen. They are found to be active for the hydrogenation of various alkenes and alkynes under mild conditions and weakly active for C=O bond hydrogenation.

  20. Structural effects on the magnetic hyperthermia properties of iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Eric C. Abenojar

    2016-10-01

    Full Text Available Magnetic iron oxide nanoparticles (IONPs are heavily explored as diagnostic and therapeutic agents due to their low cost, tunable properties, and biocompatibility. In particular, upon excitation with an alternating current (AC magnetic field, the NPs generate localized heat that can be exploited for therapeutic hyperthermia treatment of diseased cells or pathogenic microbes. In this review, we focus on how structural changes and inter-particle interactions affect the heating efficiency of iron oxide-based magnetic NPs. Moreover, we present an overview of the different approaches to evaluate the heating performance of IONPs and introduce a new theranostic modality based on magnetic imaging guided–hyperthermia.

  1. Electron small polarons and their mobility in iron (oxyhydr)oxide nanoparticles

    DEFF Research Database (Denmark)

    Katz, Jordan E; Zhang, Xiaoyi; Attenkofer, Klaus

    2012-01-01

    Electron mobility within iron (oxyhydr)oxides enables charge transfer between widely separated surface sites. There is increasing evidence that this internal conduction influences the rates of interfacial reactions and the outcomes of redox-driven phase transformations of environmental interest....... To determine the links between crystal structure and charge-transport efficiency, we used pump-probe spectroscopy to study the dynamics of electrons introduced into iron(III) (oxyhydr)oxide nanoparticles via ultrafast interfacial electron transfer. Using time-resolved x-ray spectroscopy and ab initio...

  2. Synthesis of magnetic iron oxide nanoparticles toward arsenic removal from drinking water

    International Nuclear Information System (INIS)

    Starbird Perez, Ricardo; Montero Campos, Virginia

    2015-01-01

    A high contact area material is supplied to be used in the treatment of water contaminated with arsenic. Synthesis of iron nanoparticles is reported with superparamagnetic properties, stabilized with stearic acid. The characterization is performed through spectrophotometric, thermogravimetric and electronic transmission techniques. The presence of an emulsifier is evidenced and determinant for the stabilization of the iron oxide phase (maghemite or magnetite) with magnetic properties. The material is obtained and shows suitable properties to be used in the treatment of water for human consumption. (author) [es

  3. A cast-mold approach to iron oxide and Pt/iron oxide nanocontainers and nanoparticles with a reactive concave surface.

    Science.gov (United States)

    George, Chandramohan; Dorfs, Dirk; Bertoni, Giovanni; Falqui, Andrea; Genovese, Alessandro; Pellegrino, Teresa; Roig, Anna; Quarta, Alessandra; Comparelli, Roberto; Curri, M Lucia; Cingolani, Roberto; Manna, Liberato

    2011-02-23

    We report the synthesis of various iron oxide nanocontainers and Pt-iron oxide nanoparticles based on a cast-mold approach, starting from nanoparticles having a metal core (either Au or AuPt) and an iron oxide shell. Upon annealing, the particles evolve to asymmetric core-shells and then to heterodimers. If iodine is used to leach Au out of these structures, asymmetric core-shells evolve into "nanocontainers", that is, iron oxide nanoparticles enclosing a cavity accessible through nanometer-sized pores, while heterodimers evolve into particles with a concave region. When starting from a metal domain made of AuPt, selective leaching of the Au atoms yields the same iron oxide nanoparticle morphologies but now encasing Pt domains (in their concave region or in their cavity). We found that the concave nanoparticles are capable of destabilizing Au nanocrystals of sizes matching that of the concave region. In addition, for the nanocontainers, we propose two different applications: (i) we demonstrate loading of the cavity region of the nanocontainers with the antitumoral drug cis-platin; and (ii) we show that nanocontainers encasing Pt domains can act as recoverable photocatalysts for the reduction of a model dye.

  4. Concentration-dependent toxicity of iron oxide nanoparticles mediated by increased oxidative stress

    Directory of Open Access Journals (Sweden)

    Saba Naqvi

    2010-11-01

    Full Text Available Saba Naqvi1, Mohammad Samim2, MZ Abdin3, Farhan Jalees Ahmed4, AN Maitra5, CK Prashant6, Amit K Dinda61Faculty of Engineering and Interdisciplinary Sciences, 2Department of Chemistry, 3Department of Biotechnology, Faculty of Science, 4Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, Hamdard University, 5Department of Chemistry, University of Delhi, 6Department of Pathology, All India Institute of Medical Sciences, New Delhi, IndiaAbstract: Iron oxide nanoparticles with unique magnetic properties have a high potential for use in several biomedical, bioengineering and in vivo applications, including tissue repair, magnetic resonance imaging, immunoassay, drug delivery, detoxification of biologic fluids, cell sorting, and hyperthermia. Although various surface modifications are being done for making these nonbiodegradable nanoparticles more biocompatible, their toxic potential is still a major concern. The current in vitro study of the interaction of superparamagnetic iron oxide nanoparticles of mean diameter 30 nm coated with Tween 80 and murine macrophage (J774 cells was undertaken to evaluate the dose- and time-dependent toxic potential, as well as investigate the role of oxidative stress in the toxicity. A 15–30 nm size range of spherical nanoparticles were characterized by transmission electron microscopy and zeta sizer. MTT assay showed >95% viability of cells in lower concentrations (25–200 µg/mL and up to three hours of exposure, whereas at higher concentrations (300–500 µg/mL and prolonged (six hours exposure viability reduced to 55%–65%. Necrosis-apoptosis assay by propidium iodide and Hoechst-33342 staining revealed loss of the majority of the cells by apoptosis. H2DCFDDA assay to quantify generation of intracellular reactive oxygen species (ROS indicated that exposure to a higher concentration of nanoparticles resulted in enhanced ROS generation, leading to cell injury and death. The cell membrane injury

  5. Accumulation of magnetic iron oxide nanoparticles coated with variably sized polyethylene glycol in murine tumors

    DEFF Research Database (Denmark)

    Larsen, Esben Kjær Unmack; Nielsen, Thomas; Wittenborn, Thomas

    2012-01-01

    , lower surface charge, longer circulation half-life, and lower uptake in macrophage cells when the particles were coated with high molecular weight (Mw) PEG molecules. By use of magnetic resonance imaging, we show coating-dependent in vivo uptake in murine tumors with an optimal coating Mw of 10 000 Da......Iron oxide nanoparticles have found widespread applications in different areas including cell separation, drug delivery and as contrast agents. Due to water insolubility and stability issues, nanoparticles utilized for biological applications require coatings such as the commonly employed...

  6. Hollow Spheres of Iron Carbide Nanoparticles Encased in Graphitic Layers as Oxygen Reduction Catalysts

    DEFF Research Database (Denmark)

    Hu, Yang; Jensen, Jens Oluf; Zhang, Wei

    2014-01-01

    Nonprecious metal catalysts for the oxygen reduction reaction are the ultimate materials and the foremost subject for low‐temperature fuel cells. A novel type of catalysts prepared by high‐pressure pyrolysis is reported. The catalyst is featured by hollow spherical morphologies consisting...... of uniform iron carbide (Fe3C) nanoparticles encased by graphitic layers, with little surface nitrogen or metallic functionalities. In acidic media the outer graphitic layers stabilize the carbide nanoparticles without depriving them of their catalytic activity towards the oxygen reduction reaction (ORR...

  7. Influence of dextran coating on the magnetic behaviour of iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Dutz, Silvio [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany) and Department of Biomedical Engineering, University of Applied Sciences, Jena (Germany)]. E-mail: silvio.dutz@ipht-jena.de; Andrae, Wilfried [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany); Department of Biomedical Engineering, University of Applied Sciences, Jena (Germany); Hergt, Rudolf [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany); Mueller, Robert [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany); Oestreich, Christiane [Institute of Ceramic Materials, Freiberg University of Mining and Technology (Germany); Schmidt, Christopher [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany); Department of Materials Engineering, University of Applied Sciences, Jena (Germany); Toepfer, Jorg [Department of Materials Engineering, University of Applied Sciences, Jena (Germany); Zeisberger, Matthias [Institute for Physical High Technology, Albert-Einstein-Strasse 9, 07745 Jena (Germany); Bellemann, Matthias E. [Department of Biomedical Engineering, University of Applied Sciences, Jena (Germany)

    2007-04-15

    Magnetic iron oxide nanoparticles with mean diameters in the range from 10 to 30 nm were prepared by modified chemical precipitation routes. The particles were suspended in an aqueous solution by coating of the particles with carboxymethyldextran. A stability against agglomeration was achieved over a period of more than 7 days. In the present investigation, the structural and the magnetic properties of the nanoparticles were investigated. The influence of the dextran shell on the strength of the dipole-dipole interactions between the neighbouring particles was determined by investigation of the remanence behaviour (Henkel plot) of coated as well as of uncoated particles.

  8. Toxicity of superparamagnetic iron oxide nanoparticles: Research strategies and implications for nanomedicine

    International Nuclear Information System (INIS)

    Li Lei; Jiang Ling-Ling; Zeng Yun; Liu Gang

    2013-01-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) are one of the most versatile and safe nanoparticles in a wide variety of biomedical applications. In the past decades, considerable efforts have been made to investigate the potential adverse biological effects and safety issues associated with SPIONs, which is essential for the development of next-generation SPIONs and for continued progress in translational research. In this mini review, we summarize recent developments in toxicity studies on SPIONs, focusing on the relationship between the physicochemical properties of SPIONs and their induced toxic biological responses for a better toxicological understanding of SPIONs. (topical review - magnetism, magnetic materials, and interdisciplinary research)

  9. Design of iron oxide-based nanoparticles for MRI and magnetic hyperthermia.

    Science.gov (United States)

    Blanco-Andujar, Cristina; Walter, Aurelie; Cotin, Geoffrey; Bordeianu, Catalina; Mertz, Damien; Felder-Flesch, Delphine; Begin-Colin, Sylvie

    2016-07-01

    Iron oxide nanoparticles are widely used for biological applications thanks to their outstanding balance between magnetic properties, surface-to-volume ratio suitable for efficient functionalization and proven biocompatibility. Their development for MRI or magnetic particle hyperthermia concentrates much of the attention as these nanomaterials are already used within the health system as contrast agents and heating mediators. As such, the constant improvement and development for better and more reliable materials is of key importance. On this basis, this review aims to cover the rational design of iron oxide nanoparticles to be used as MRI contrast agents or heating mediators in magnetic hyperthermia, and reviews the state of the art of their use as nanomedicine tools.

  10. Synthesis of nickel zinc iron nanoparticles by coprecipitation technique

    Directory of Open Access Journals (Sweden)

    Kandasamy Velmurugan

    2010-09-01

    Full Text Available Nanoparticles nickel ferrite of size 6 - 8 nm, synthesized by the coprecipitation method with x varying from 0 to 1.0. The powder samples were characterized by XRD, VSM and FTIR. The average crystallite sizes of the particles were determined from X-ray diffraction. X-ray analysis showed that the samples were cubic spinel. The lattice constant (a o increased with the increase in zinc substitution. The specific saturation magnetization (M S of the particles was measured at room temperature. The magnetic parameter of M S, was found to decrease with the increase in zinc substitution. Fourier transform infrared spectroscopy (FTIR spectra of the Ni1-xZn xFe2O4 with x = 0, 0.5, 1 in the range 400 - 4000 cm-1 were reported. The spinel structure and the crystalline water adsorption of Ni1-xZn xFe2O4 nanoparticles were studied by using FTIR.

  11. Ordered mesoporous ferrosilicate materials with highly dispersed iron oxide nanoparticles and investigation of their unique magnetic properties.

    Science.gov (United States)

    Srinivasu, Pavuluri; Suresh, Koppoju; Datt, Gopal; Abhayankar, Ashutosh C; Rao, Pothuraju Nageswara; Lakshmi Kantam, Mannepalli; Bhargava, Suresh K; Tang, Jing; Yamauchi, Yusuke

    2014-11-07

    Ordered mesoporous ferrosilicate materials with highly dispersed iron oxide nanoparticles are directly synthesized through a hydrothermal approach under acidic conditions. The obtained samples possess a high surface area (up to 1236 m(2) g(-1)) and a large pore volume (up to 1.1 cm(3) g(-1)). By changing the amount of iron content, the magnetic properties can be tuned.

  12. Influence of iron and copper nanoparticle powder on the production of lignocellulose degrading enzymes in the fungus Trametes versicolor

    Czech Academy of Sciences Publication Activity Database

    Shah, V.; Dobiášová, Petra; Baldrian, Petr; Nerud, František; Kumar, A.; Seal, S.

    2010-01-01

    Roč. 178, 1-3 (2010), s. 1141-1145 ISSN 0304-3894 R&D Projects: GA MŠk LC06066 Institutional research plan: CEZ:AV0Z50200510 Keywords : Iron nanoparticles * Copper nanoparticles * Lignocellulose enzymes Subject RIV: EE - Microbiology, Virology Impact factor: 3.723, year: 2010

  13. At the frontier between heterogeneous and homogeneous catalysis : hydrogenation of olefins and alkynes with soluble iron nanoparticles

    NARCIS (Netherlands)

    Rangheard, Claudine; Julián Fernández, César de; Phua, Pim-Huat; Hoorn, Johan; Lefort, Laurent; Vries, Johannes G. de

    2010-01-01

    The use of non-supported Fe nanoparticles in the hydrogenation of unsaturated C–C bonds is a green catalytic concept at the frontier between homogeneous and heterogeneous catalysis. Iron nanoparticles can be obtained by reducing Fe salts with strong reductants in various solvents. FeCl3 reduced by 3

  14. Tumour Cell Labelling by Magnetic Nanoparticles with Determination of Intracellular Iron Content and Spatial Distribution of the Intracellular Iron

    Directory of Open Access Journals (Sweden)

    Alfred Cuschieri

    2013-04-01

    Full Text Available Magnetically labelled cells are used for in vivo cell tracking by MRI, used for the clinical translation of cell-base therapies. Studies involving magnetic labelled cells may include separation of labelled cells, targeted delivery and controlled release of drugs, contrast enhanced MRI and magnetic hyperthermia for the in situ ablation of tumours. Dextran-coated super-paramagnetic iron oxide (SPIO ferumoxides are used clinically as an MR contrast agents primarily for hepatic imaging. The material is also widely used for in vitro cell labelling, as are other SPIO-based particles. Our results on the uptake by human cancer cell lines of ferumoxides indicate that electroporation in the presence of protamine sulphate (PS results in rapid high uptake of SPIO nanoparticles (SPIONs by parenchymal tumour cells without significant impairment of cell viability. Quantitative determination of cellular iron uptake performed by colorimetric assay is in agreement with data from the literature. These results on intracellular iron content together with the intracellular distribution of SPIONs by magnetic force microscopy (MFM following in vitro uptake by parenchymal tumour cells confirm the potential of this technique for clinical tumour cell detection and destruction.

  15. A study of formation of iron nanoparticles in aluminium matrix with helium pores

    Czech Academy of Sciences Publication Activity Database

    Kichanov, S.E.; Kozlenko, D. P.; Belushkin, A.V.; Reutov, V.F.; Samoilenko, S.O.; Jirák, Zdeněk; Savenko, B. N.; Bulavin, L. A.; Zubavichus, Y.V.

    2012-01-01

    Roč. 351, č. 1 (2012), "012013-1"-"012013-5" ISSN 1742-6588. [International Workshop on SANS-YuMO User Meeting at the Start-up of Scientific Experiments on the IBR-2M Reactor - Devoted to the 75th anniversary of Yu M Ostanevich's Birth /2./. Dubna, 27.05.2011-30.05.2011] Institutional research plan: CEZ:AV0Z10100521 Keywords : iron nanoparticles * aluminium matrix * helium pores Subject RIV: BM - Solid Matter Physics ; Magnetism

  16. Removal of Reactive Red 198 by Nanoparticle Zero Valent Iron in the Presence of Hydrogen Peroxide

    OpenAIRE

    Siroos Shojaei; Somaye Khammarnia; Saeed Shojaei; Mojtaba Sasani

    2017-01-01

    Although dyes are widely used in textile industries, they are carcinogenic, teratogenic and mutagenic. Industries discharge their wastewater containing a variety of colors into water resources and make harmful effect on the environment. The present study aims to Evaluate removal of reactive red 198 by nanoparticle zero valent iron (NZVI) in the presence of hydrogen peroxide from aqueous solution. The effective parameters on the removal of dye such as the hydrogen peroxide concentration of NZV...

  17. Heating Efficiency of Iron Oxide Nanoparticles in Hyperthermia: Effect of Preparation Conditions

    Czech Academy of Sciences Publication Activity Database

    Parmar, H. G.; Smolková, I. S.; Kazantseva, N. E.; Babayan, V.; Pastorek, M.; Pizúrová, Naděžda

    2014-01-01

    Roč. 50, č. 11 (2014), č. článku 5200504. ISSN 0018-9464. [IEEE International Magnetics Conference (Intermag). Dresden, 04.05.2014-08.05.2014] Institutional support: RVO:68081723 Keywords : Iron oxide nanoparticles (NPs) * magnetic hyperthermia (MH) * Mossbauer spectroscopy * Rietveld refinement Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.386, year: 2014

  18. Recovery of iron/iron oxide nanoparticles from solution: comparison of methods and their effects

    International Nuclear Information System (INIS)

    Nurmi, James T.; Sarathy, Vaishnavi; Tratnyek, Paul G.; Baer, Donald R.; Amonette, James E.; Karkamkar, Abhi

    2011-01-01

    Most methods currently being used to recover Fe 0 -core/oxide-shell nanoparticles from solutions (including the solvents they are synthesized or stored in) are potentially problematic because they may alter the particle composition (e.g., depositing salts formed from solutes) or leave the particles prone to transformations during subsequent storage and handling (e.g., due to residual moisture). In this study, several methods for recovery of nanoparticles from aqueous solution were studied to determine how they affect the structure and reactivity of the recovered materials. Simple washing of the nanoparticles during vacuum filtration (i.e., “flash drying”) can leave up to ∼17 wt% residual moisture. Modeling calculations suggest this moisture is mostly capillary or matric water held between particles and particle aggregates, which can be removed by drying for short periods at relative vapor pressures below 0.9. Flash drying followed by vacuum drying, all under N 2 , leaves no detectable residue from precipitation of solutes (detectable by X-ray photoelectron spectroscopy, XPS), no significant changes in overall particle composition or structure (determined by transmission electron microscopy, TEM), and negligible residual moisture (by thermogravimetric analysis, TGA). While this improved flash-drying protocol may be the preferred method for recovering nanoparticles for many purposes, we found that Fe 0 -core/oxide-shell nanoparticles still exhibit gradual aging during storage when characterized electrochemically with voltammetry.

  19. Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Paula I.P. [i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica (Portugal); Laia, César A.T. [Laboratório Associado para a Química Verde (LAQV), REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Carvalho, Alexandra [i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica (Portugal); Pereira, Laura C.J.; Coutinho, Joana T. [C2TN, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066 Bobadela LRS (Portugal); Ferreira, Isabel M.M., E-mail: imf@fct.unl.pt [i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica (Portugal); Novo, Carlos M.M. [Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, IHMT/UNL, 1349-008 Lisboa (Portugal); Borges, João Paulo, E-mail: jpb@fct.unl.pt [i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica (Portugal)

    2016-10-15

    Highlights: • Superparamagnetic iron oxide nanoparticles were stabilized with oleic acid. • Maximum stabilization was achieved at neutral pH. • Magnetic resonance imaging and magnetic hyperthermia applications were tested. • The produced nanoparticles are viable for both biomedical applications. - Abstract: Iron oxide nanoparticles (Fe{sub 3}O{sub 4}, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

  20. Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications

    International Nuclear Information System (INIS)

    Soares, Paula I.P.; Laia, César A.T.; Carvalho, Alexandra; Pereira, Laura C.J.; Coutinho, Joana T.; Ferreira, Isabel M.M.; Novo, Carlos M.M.; Borges, João Paulo

    2016-01-01

    Highlights: • Superparamagnetic iron oxide nanoparticles were stabilized with oleic acid. • Maximum stabilization was achieved at neutral pH. • Magnetic resonance imaging and magnetic hyperthermia applications were tested. • The produced nanoparticles are viable for both biomedical applications. - Abstract: Iron oxide nanoparticles (Fe 3 O 4 , IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

  1. A portable Hall magnetometer probe for characterization of magnetic iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jefferson F.D.F.; Costa, Mateus C.; Louro, Sonia R.W.; Bruno, Antonio C., E-mail: acbruno@puc-rio.br

    2017-03-15

    We have built a portable Hall magnetometer probe, for measuring magnetic properties of iron oxide nanoparticles, that can be used for bulk materials and liquid samples as well. The magnetometer probe consists of four voltage-programmable commercial Hall sensors and a thin acrylic plate for positioning the sensors. In order to operate, it needs to be attached to a pole of an electromagnet and connected to an AD converter and a computer. It acquires a complete magnetization curve in a couple of minutes and has a magnetic moment sensitivity of 3.5×10{sup −7} Am{sup 2}. We tested its performance with magnetic nanoparticles containing an iron oxide core and having coating layers with different sizes. The magnetization results obtained were compared with measurements performed on commercial stand-alone magnetometers, and exhibited errors of about ±0.2 Am{sup 2}/kg (i.e 0.4%) at saturation and below 0.5 Am{sup 2}/kg (i.e. 10%) at remanence. - Highlights: • A low-cost portable Hall magnetometer probe has been built. • The Hall magnetometer probe can be attached to any electromagnet. • The Hall probe was calibrated and successfully compared to industry standard magnetometers. • The Hall probe was able to measure iron oxide nanoparticles with different coatings.

  2. A Study of Efficiency of Zero-valent Iron Nanoparticles in Degradation of Trichlorethylene from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Samaneh Dehghan

    2016-12-01

    mg/l, and contact time= 86 min. The results of kinetic studies revealed that TCE degradation by nZVI follows first-order kinetic model. Conclusion: It is conclude that zero-valent iron nanoparticles have a good efficiency in the degradation of TCE. On the other hand, separation of these nanoparticles is simple due to its magnetism properties, which can improve the use of these nanoparticles

  3. Caveolin-1 and CDC42 mediated endocytosis of silica-coated iron oxide nanoparticles in HeLa cells

    Directory of Open Access Journals (Sweden)

    Nils Bohmer

    2015-01-01

    Full Text Available Nanomedicine is a rapidly growing field in nanotechnology, which has great potential in the development of new therapies for numerous diseases. For example iron oxide nanoparticles are in clinical use already in the thermotherapy of brain cancer. Although it has been shown, that tumor cells take up these particles in vitro, little is known about the internalization routes. Understanding of the underlying uptake mechanisms would be very useful for faster and precise development of nanoparticles for clinical applications. This study aims at the identification of key proteins, which are crucial for the active uptake of iron oxide nanoparticles by HeLa cells (human cervical cancer as a model cell line. Cells were transfected with specific siRNAs against Caveolin-1, Dynamin 2, Flotillin-1, Clathrin, PIP5Kα and CDC42. Knockdown of Caveolin-1 reduces endocytosis of superparamagnetic iron oxide nanoparticles (SPIONs and silica-coated iron oxide nanoparticles (SCIONs between 23 and 41%, depending on the surface characteristics of the nanoparticles and the experimental design. Knockdown of CDC42 showed a 46% decrease of the internalization of PEGylated SPIONs within 24 h incubation time. Knockdown of Dynamin 2, Flotillin-1, Clathrin and PIP5Kα caused no or only minor effects. Hence endocytosis in HeLa cells of iron oxide nanoparticles, used in this study, is mainly mediated by Caveolin-1 and CDC42. It is shown here for the first time, which proteins of the endocytotic pathway mediate the endocytosis of silica-coated iron oxide nanoparticles in HeLa cells in vitro. In future studies more experiments should be carried out with different cell lines and other well-defined nanoparticle species to elucidate possible general principles.

  4. Tumor cell-specific prodrugs using arsonic acid-presenting iron oxide nanoparticles with high sensitivity.

    Science.gov (United States)

    Minehara, Hiroki; Narita, Asako; Naka, Kensuke; Tanaka, Kazuo; Chujo, Moeko; Nagao, Masaya; Chujo, Yoshiki

    2012-08-01

    We report the tumor cell-selective prodrugs based on the arsonic acid-presenting iron oxide nanoparticles. We synthesized the well-dispersed nanoparticles having arsonoacetic acid which is composed of the low toxic As(V) form. From the analyses of the reaction products, it is suggested that the reduction by dithiothreitol with arsonoacetic acid and the modified nanoparticles could generate the highly-toxic As(III) species. In the MTT assays, it was found that the cell viabilities of HeLaS3 and especially HepG2 were reduced in the presence of the modified nanoparticles. In contrast, a slight effect on viability was observed with primary mouse hepatocytes. The viabilities showed good agreements with the amounts of intracellular reduced glutathione concentrations. Furthermore, the valid concentrations of the modified nanoparticles for tumor-specific cytotoxicity were similar level in MRI measurements. These results indicate that arsonic acid-presenting nanoparticles should be a good platform for developing highly-sensitive tumor-specific prodrugs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Effect of coating on the environmental applications of zero valent iron nanoparticles: the lindane case.

    Science.gov (United States)

    San Román, I; Galdames, A; Alonso, M L; Bartolomé, L; Vilas, J L; Alonso, R M

    2016-09-15

    Commercial stabilized slurry of zero-valent iron nanoparticles (nZVI) as well as laboratory-synthesized polymer-stabilized NZVI nanoparticles were used for lindane (γ-hexachlorocyclohexane) degradation studies in aqueous solution. In the present study, polymer-stabilized iron nanoparticles were stabilized using polyethylene glycol (PEG, Mn ~400 and ~950-1050) and polytetrahydrofuran (PTHF, Mn ~650). To study the effectiveness of the different nanoparticles, a quantitative monitorization of lindane degradation by using solid-phase extraction (SPE) and a qualitative measurement of generated volatile by-products by headspace-solid phase microextraction (HS-SPME) followed by GC/MS were carried out. The obtained data were compared and contrasted with the results obtained in previous work. Results showed that the nanoparticles studied in this work possess superior dechlorination performance compared with previous observations. The freshly prepared Fe(0)-PEG400, Fe(0)-PEG1050 and Fe(0)-PTHF exhibited high reactivity during the dechlorination process of lindane in a very short time. The results obtained with the synthesized nanoparticles were similar to those obtained with commercial nanoparticles. However, in all cases reactivity decreased at reaction's late stage. Degradation of lindane by the studied nanoparticles removed 99.9% of the lindane initial concentration after 72h, except for Fe(0)-PTHF nanoparticles, for which the reaction stopped after 5min. In all cases, the reaction followed a second order kinetics. Finally, comparing the results from this study with our previous work, where different nature polymers were considered (Fe(0)-CMC, Fe(0)-PAA and Fe(0)-PAP), more gradual degradation profile of lindane was observed for Fe(0)-PAA and Fe(0)-CMC. It should be noted that in the present case, the reaction of lindane was speeded up with commercial and Fe(0)-PEG nanoparticles. Nevertheless, in the later case, the composition of by-products was affected by the presence

  6. Variable Temperature 57Fe-Mössbauer Spectroscopy Study of Nanoparticle Iron Carbides

    Directory of Open Access Journals (Sweden)

    Alex Scrimshire

    2015-12-01

    Full Text Available Near-phase-pure nanoparticle iron carbides (Fe3C and Fe5C2 were synthesised. Debye model calculations were used with hyperfine parameters gathered by 57Fe Mössbauer spectroscopy within a temperature range of 10 K to 293 K, with analysis providing Debye temperatures of 422 K and 364 K for two Fe sites in Fe5C2 and 355 K for ferromagnetic Fe3C. The intrinsic isomer shifts were calculated as 0.45 mm s−1 and 0.43 mm s−1 for iron sites 1 and 2 respectively in Fe5C2 and 0.42 mm s−1 for Fe3C. Recoil-free fractions for the two iron sites were also calculated at f300 0.785 and 0.726 for site 1 and 2 respectively.

  7. Iron oxide nanoparticles embedded in activated carbons prepared from hydrothermally treated waste biomass.

    Science.gov (United States)

    Hao, Wenming; Björkman, Eva; Yun, Yifeng; Lilliestråle, Malte; Hedin, Niklas

    2014-03-01

    Particles of iron oxide (Fe3O4 ; 20–40 nm) were embedded within activated carbons during the activation of hydrothermally carbonized (HTC) biomasses in a flow of CO2. Four different HTC biomass samples (horse manure, grass cuttings, beer production waste, and biosludge) were used as precursors for the activated carbons. Nanoparticles of iron oxide formed from iron catalyst included in the HTC biomasses. After systematic optimization, the activated carbons had specific surface areas of about 800 m2g1. The pore size distributions of the activated carbons depended strongly on the degree of carbonization of the precursors. Activated carbons prepared from highly carbonized precursors had mainly micropores, whereas those prepared from less carbonized precursors contained mainly mesopores. Given the strong magnetism of the activated carbon–nano-Fe3O4 composites, they could be particularly useful for water purification.

  8. Synthesis, characterization and magnetorheological properties of carbonyl iron suspension with superparamagnetic nanoparticles as an additive

    International Nuclear Information System (INIS)

    Leong, Siti Asma’ Nikmat; Mohd Samin, Pakharuddin; Idris, Ani; Rahman, Azura Hanis A; Mazlan, Saiful Amri

    2016-01-01

    Magnetorheological (MR) fluids are suspensions of micron-sized particles dispersed in carrier fluid. Due to high density magnetic particles, MR fluids are facing the problem with the instability of the suspension caused by high settling rate. Recently, researches have been conducted on the advantages of using the mixture of magnetic nanoparticles and microparticles, called bidisperse MR fluids. However, even though the sedimentation stability is improved, there is a reduction in dynamic yield stress when the nanoparticle is introduced. In this work, the investigation of magnetic iron nanoparticles (γ-Fe 2 O 3 ) as an additive to magnetic carbonyl iron (CI) suspension has been proposed so as to improve the sedimentation stability and redispersibility, but at the same time enhance the MR performance. The results indicated that the addition of nanoparticles reduced the sedimentation rate, improved redispersibility and enhanced the rheological performance of MR fluids as the particle fill the voids between the microparticles and strengthened the interparticle chains contributing to well-arranged particle structures. (paper)

  9. Electrochemical preparation of iron cuboid nanoparticles and their catalytic properties for nitrite reduction

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yanxin; Chen Shengpei; Chen Qingsong; Zhou Zhiyou [State Key Lab of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Sun Shigang [State Key Lab of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)], E-mail: sgsun@xmu.edu.cn

    2008-10-01

    Iron cuboid nanoparticles supported on glassy carbon (denoted nm-Fe/GC) were prepared by electrochemical deposition under cyclic voltammetric (CV) conditions. The structure and composition of the Fe nanomaterials were characterized by scanning electron microscopy (SEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). The results demonstrated that the Fe cuboid nanoparticles are dispersed discretely on GC substrate with an average size ca. 171 nm, and confirmed that the electrochemical synthesized nanocubes are single crystals of pure Fe. The catalytic properties of the Fe cuboid nanoparticles towards nitrite electroreduction were investigated, and enhanced electrocatalytic activity of the Fe nanocubes has been determined. In comparison with the data obtained on a bulk-Fe electrode, the onset potential of nitrite reduction on nm-Fe/GC is positively sifted by 100 mV, and the steady reduction current density is enhanced about 2.4-3.2 times.

  10. Electrochemical preparation of iron cuboid nanoparticles and their catalytic properties for nitrite reduction

    International Nuclear Information System (INIS)

    Chen Yanxin; Chen Shengpei; Chen Qingsong; Zhou Zhiyou; Sun Shigang

    2008-01-01

    Iron cuboid nanoparticles supported on glassy carbon (denoted nm-Fe/GC) were prepared by electrochemical deposition under cyclic voltammetric (CV) conditions. The structure and composition of the Fe nanomaterials were characterized by scanning electron microscopy (SEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX). The results demonstrated that the Fe cuboid nanoparticles are dispersed discretely on GC substrate with an average size ca. 171 nm, and confirmed that the electrochemical synthesized nanocubes are single crystals of pure Fe. The catalytic properties of the Fe cuboid nanoparticles towards nitrite electroreduction were investigated, and enhanced electrocatalytic activity of the Fe nanocubes has been determined. In comparison with the data obtained on a bulk-Fe electrode, the onset potential of nitrite reduction on nm-Fe/GC is positively sifted by 100 mV, and the steady reduction current density is enhanced about 2.4-3.2 times

  11. Recent advances in synthesis and surface modification of superparamagnetic iron oxide nanoparticles with silica

    Energy Technology Data Exchange (ETDEWEB)

    Sodipo, Bashiru Kayode, E-mail: bashirsodipo@gmail.com [School of Physics, Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia); Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia); Aziz, Azlan Abdul [School of Physics, Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia); Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia)

    2016-10-15

    Research on synthesis of superparamagnetic iron oxide nanoparticles (SPION) and its surface modification for biomedical applications is of intense interest. Due to superparamagnetic property of SPION, the nanoparticles have large magnetic susceptibility, single magnetic domain and controllable magnetic behaviour. However, owing to easy agglomeration of SPION, surface modification of the magnetic particles with biocompatible materials such as silica nanoparticle has gained much attention in the last decade. In this review, we present recent advances in synthesis of SPION and various routes of producing silica coated SPION. - Highlights: • We present recent advances in synthesis of SPION and various routes of producing silica coated SPION • The synthetic routes of producing SPION can be classified into three: physical, chemical and biological methods. • The chemical method is the most cited method of producing SPION and it sub-classified into liquid and gas phase. • The techniques of producing silica coated SPION is grouped into seeded and non-seeded methods.

  12. Reproducibility of the Synthesis of Iron Oxide Nanoparticles Produced by Laser Pyrolysis

    Science.gov (United States)

    Alexandrescu, R.; Bouzas, V.; Costo, R.; Dumitrache, F.; García, M. A.; Morales, M. P.; Morjan, I.; Serna, C. J.; Veintemillas-Verdaguer, S.

    2010-10-01

    During the development of the BONSAI Project, the need for high quantities of iron oxide nanoparticles with some specific characteristics intensified the problem of the reproducibility in the nanoparticle production. Given the fact that the reaction yield for the production of the smallest and more homogeneous nanoparticles (BONFEX4) was very low (in the range of 1g/day), the process had to be repeated several times. These repetitions involved the use of three different CO2 lasers (two of monomodal gaussian beams TEMoo mode with spot sizes of 4 and 3.5 mm and one multimodal of 4 mm spot size). Keeping constant the rest of the experiment parameters (including the laser density) we obtained similar powders in nature as revealed by X-ray diffraction, and similar particle size distributions, but with different magnetic properties. When the same laser was used the reproducibility of the magnetic properties increased significantly.

  13. Application of magnetic iron oxide nanoparticles in stabilization process of biological molecules

    Directory of Open Access Journals (Sweden)

    Mohammad Hossien Salmani

    2017-07-01

    Conclusion: Co-precipitation method is an easy way to prepare magnetic nanoparticles of iron with a large surface and small particle size, which increases the ability of these particles to act as a suitable carrier for enzyme stabilization. Adequate modification of the surface of these nanoparticles enhances their ability to bind to biological molecules. The immobilized protein or enzyme on magnetic nanoparticles are more stable against structural changes, temperature and pH in comparison with un-stabilized structures, and it is widely used in various sciences, including protein isolation and purification, pharmaceutical science, and food analysis. Stabilization based on the covalent bonds and physical absorption is nonspecific, which greatly limits their functionality. The process of stabilization through bio-mediums provide a new method to overcome the selectivity problem.

  14. Development of iron-based nanoparticles for Cr(VI removal from drinking water

    Directory of Open Access Journals (Sweden)

    Vourlias G.

    2013-01-01

    Full Text Available A great deal of research over recent decades has been motivated by the requirement to lower the concentration of chromium in drinking water. This study has been conducted to determine the feasibility of iron-based nanoparticles for chromium removal from contaminated water. Single Fe, Fe3O4 and binary Fe/Fe3O4 nanoparticles were grown at the 45-80 nm size range using the solar physical vapor deposition technique and tested as potential hexavalent chromium removing agents from aqueous solutions. Due to their higher electron donation ability compared to the Fe3O4 ones, single Fe nanoparticles exhibited the highest Cr(VI removal capacity of more than 3 µg/mg while maintaining a residual concentration 50 µg/L, equal to the regulation limit for drinking water. In combination to their facile and fast magnetic separation, the applicability of the studied particles in water treatment facilities should be considered.

  15. Strategies to optimize the biocompatibility of iron oxide nanoparticles - ;SPIONs safe by design;

    Science.gov (United States)

    Janko, Christina; Zaloga, Jan; Pöttler, Marina; Dürr, Stephan; Eberbeck, Dietmar; Tietze, Rainer; Lyer, Stefan; Alexiou, Christoph

    2017-06-01

    Various nanoparticle systems have been developed for medical applications in recent years. For constant improvement of efficacy and safety of nanoparticles, a close interdisciplinary interplay between synthesis, physicochemical characterizations and toxicological investigations is urgently needed. Based on combined toxicological data, we follow a ;safe-by design; strategy for our superparamagnetic iron oxide nanoparticles (SPION). Using complementary interference-free toxicological assay systems, we initially identified agglomeration tendencies in physiological fluids, strong uptake by cells and improvable biocompatibility of lauric acid (LA)-coated SPIONs (SPIONLA). Thus, we decided to further stabilize those particles by an artificial protein corona consisting of serum albumin. This approach finally lead to increased colloidal stability, augmented drug loading capacity and improved biocompatibility in previous in vitro assays. Here, we show in whole blood ex vivo and on isolated red blood cells (RBC) that a protein corona protects RBCs from hemolysis by SPIONs.

  16. Fluorophore-conjugated iron oxide nanoparticle labeling and analysis of engrafting human hematopoietic stem cells

    DEFF Research Database (Denmark)

    Maxwell, Dustin J; Bonde, Jesper; Hess, David A

    2008-01-01

    The use of nanometer-sized iron oxide particles combined with molecular imaging techniques enables dynamic studies of homing and trafficking of human hematopoietic stem cells (HSC). Identifying clinically applicable strategies for loading nanoparticles into primitive HSC requires strictly defined...... to the dextran coat for fluorescence-activated cell sorting purification eliminated spurious signals from nonsequestered nanoparticle contaminants. A short-term defined incubation strategy was developed that allowed efficient labeling of both quiescent and cycling HSC, with no discernable toxicity in vitro...... or in vivo. Transplantation of purified primary human cord blood lineage-depleted and CD34(+) cells into immunodeficient mice allowed detection of labeled human HSC in the recipient bones. Flow cytometry was used to precisely quantitate the cell populations that had sequestered the nanoparticles...

  17. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    International Nuclear Information System (INIS)

    Okoli, Chuka; Boutonnet, Magali; Järås, Sven; Rajarao-Kuttuva, Gunaratna

    2012-01-01

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  18. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    Science.gov (United States)

    Okoli, Chuka; Boutonnet, Magali; Järås, Sven; Rajarao-Kuttuva, Gunaratna

    2012-10-01

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  19. Refinement of adsorptive coatings for fluorescent riboflavin-receptor-targeted iron oxide nanoparticles.

    Science.gov (United States)

    Tsvetkova, Yoanna; Beztsinna, Nataliia; Jayapaul, Jabadurai; Weiler, Marek; Arns, Susanne; Shi, Yang; Lammers, Twan; Kiessling, Fabian

    2016-01-01

    Flavin mononucleotide (FMN) is a riboflavin derivative that can be exploited to target the riboflavin transporters (RFTs) and the riboflavin carrier protein (RCP) in cells with high metabolic activity. In this study we present the synthesis of different FMN-coated ultrasmall superparamagnetic iron oxide nanoparticles (USPIOs) and their efficiency as targeting contrast agents. Since FMN alone cannot stabilize the nanoparticles, we used adenosine phosphates--AMP, ADP and ATP--as spacers to obtain colloidally stable nanoparticles. Nucleotides with di- and triphosphate groups were intended to increase the USPIO charge and thus improve zeta potential and stability. However, all nanoparticles formed negatively charged clusters with similar properties in terms of zeta potential (-28 ± 2 mV), relaxivity (228-259 mM(-1) s(-1) at 3 T) and hydrodynamic radius (53-85 nm). Molecules with a higher number of phosphate groups, such as ADP and ATP, have a higher adsorption affinity towards iron oxide, which, instead of providing more charge, led to partial desorption and replacement of FMN. Hence, we obtained USPIOs carrying different amounts of targeting agent, which significantly influenced the nanoparticles' uptake. The nanoparticles' uptake by different cancer cells and HUVECs was evaluated photometrically and with MR relaxometry, showing that the cellular uptake of the USPIOs increases with the FMN amount on their surface. Thus, for USPIOs targeted with riboflavin derivatives the use of spacers with increasing numbers of phosphate groups does not improve either zeta potential or the particles' stability, but rather detaches the targeting moieties from their surface, leading to lower cellular uptake. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Protein-functionalized magnetic iron oxide nanoparticles: time efficient potential-water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Okoli, Chuka [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden); Boutonnet, Magali; Jaeras, Sven [Royal Institute of Technology (KTH), Chemical Technology (Sweden); Rajarao-Kuttuva, Gunaratna, E-mail: gkr@kth.se [Royal Institute of Technology (KTH), Environmental Microbiology (Sweden)

    2012-10-15

    Recent advances in nanoscience suggest that the existing issues involving water quality could be resolved or greatly improved using nanomaterials, especially magnetic iron oxide nanoparticles. Magnetic nanoparticles have been synthesized for the development and use, in association with natural coagulant protein for water treatment. The nanoparticles size, morphology, structure, and magnetic properties were characterized by transmission electron microscope, X-ray diffraction, and superconducting quantum interference device magnetometry. Purified Moringa oleifera protein was attached onto microemulsions-prepared magnetic iron oxide nanoparticles (ME-MION) to form stable protein-functionalized magnetic nanoparticles (PMO+ME-MION). The turbidity removal efficiency in both synthetic and surface water samples were investigated and compared with the commonly used synthetic coagulant (alum) as well as PMO. More than 90 % turbidity could be removed from the surface waters within 12 min by magnetic separation of PMO+ME-MION; whereas gravimetrically, 70 % removal in high and low turbid waters can be achieved within 60 min. In contrast, alum requires 180 min to reduce the turbidity of low turbid water sample. These data support the advantage of separation with external magnetic field (magnetophoresis) over gravitational force. Time kinetics studies show a significant enhancement in ME-MION efficiency after binding with PMO implying the availability of large surface of the ME-MION. The coagulated particles (impurities) can be removed from PMO+ME-MION by washing with mild detergent or cleaning solution. To our knowledge, this is the first report on surface water turbidity removal using protein-functionalized magnetic nanoparticle.

  1. Transport and viability of Escherichia coli cells in clean and iron oxide coated sand following coating with silver nanoparticles.

    Science.gov (United States)

    Ngwenya, Bryne T; Curry, Philip; Kapetas, Leon

    2015-08-01

    A mechanistic understanding of processes controlling the transport and viability of bacteria in porous media is critical for designing in situ bioremediation and microbiological water decontamination programs. We investigated the combined influence of coating sand with iron oxide and silver nanoparticles on the transport and viability of Escherichia coli cells under saturated conditions. Results showed that iron oxide coatings increase cell deposition which was generally reversed by silver nanoparticle coatings in the early stages of injection. These observations are consistent with short-term, particle surface charge controls on bacteria transport, where a negatively charged surface induced by silver nanoparticles reverses the positive charge due to iron oxide coatings, but columns eventually recovered irreversible cell deposition. Silver nanoparticle coatings significantly increased cell inactivation during transit through the columns. However, when viability data is normalised to volume throughput, only a small improvement in cell inactivation is observed for silver nanoparticle coated sands relative to iron oxide coating alone. This counterintuitive result underscores the importance of net surface charge in controlling cell transport and inactivation and implies that the extra cost for implementing silver nanoparticle coatings on porous beds coated with iron oxides may not be justified in designing point of use water filters in low income countries. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Influence of experimental parameters on iron oxide nanoparticle properties synthesized by thermal decomposition: size and nuclear magnetic resonance studies

    Science.gov (United States)

    Belaïd, Sarah; Stanicki, Dimitri; Vander Elst, Luce; Muller, Robert N.; Laurent, Sophie

    2018-04-01

    A study of the experimental conditions to synthesize monodisperse iron oxide nanocrystals prepared from the thermal decomposition of iron(III) acetylacetonate was carried out in the presence of surfactants and a reducing agent. The influence of temperature, synthesis time and surfactant amounts on nanoparticle properties is reported. This investigation combines relaxometric characterization and size properties. The relaxometric behavior of the nanomaterials depends on the selected experimental parameters. The synthesis of iron oxide nanoparticles with a high relaxivity and a high saturation magnetization can be obtained with a short reaction time at high temperature. Moreover, the influence of surfactant concentrations determines the optimal value in order to produce iron oxide nanoparticles with a narrow size distribution. The optimized synthesis is rapid, robust and reproductive, and produces nearly monodisperse magnetic nanocrystals.

  3. A detailed study on the transition from the blocked to the superparamagnetic state of reduction-precipitated iron oxide nanoparticles

    Science.gov (United States)

    Witte, K.; Bodnar, W.; Mix, T.; Schell, N.; Fulda, G.; Woodcock, T. G.; Burkel, E.

    2016-04-01

    Magnetic iron oxide nanoparticles were prepared by salt-assisted solid-state chemical precipitation method with alternating fractions of the ferric iron content. The physical properties of the precipitated nanoparticles mainly consisting of magnetite were investigated by means of transmission electron microscopy, high energy X-ray diffraction, vibrating sample magnetometry and Mössbauer spectroscopy. With particle sizes ranging from 16.3 nm to 2.1 nm, a gradual transition from the blocked state to the superparamagnetic state was observed. The transition was described as a dependence of the ferric iron content used during the precipitation. Composition, mean particle size, coercivity, saturation polarisation, as well as hyperfine interaction parameters and their evolution were studied systematically over the whole series of iron oxide nanoparticles.

  4. Multiple morphologies of gold-magnetite heterostructure nanoparticles are effectively functionalized with protein for cell targeting.

    Science.gov (United States)

    Krystofiak, Evan S; Mattson, Eric C; Voyles, Paul M; Hirschmugl, Carol J; Albrecht, Ralph M; Gajdardziska-Josifovska, Marija; Oliver, Julie A

    2013-08-01

    Nanoparticles composed of a magnetic iron oxide core surrounded by a metal shell have utility in a broad range of biomedical applications. However, the presence of surface energy differences between the two components makes wetting of oxide with metal unfavorable, precluding a "core-shell" structure of an oxide core completely surrounded by a thin metal shell. Three-dimensional island growth followed by island coalescence into thick shells is favored over the two-dimensional layer-by-layer growth of a thin, continuous metal coating of a true core-shell. Aqueous synthesis of gold-coated magnetite nanoparticles with analysis by infrared, energy-dispersive X-ray, and electron energy loss spectroscopies; high-resolution transmission electron microscopy; selected area electron diffraction; and high-angle annular dark-field scanning transmission electron microscopy showed two distinct morphologies that are inconsistent with an idealized core-shell. The majority were isolated ~16-22-nm-diameter nanoparticles consisting of ~7-nm-diameter magnetite and a thick deposition of gold, most often discontinuous, with some potentially "sandwiched" morphologies. A minority were aggregates of agglomerated magnetite decorated with gold but displaying significant bare magnetite. Both populations were successfully conjugated to fibrinogen and targeted to surface-activated platelets, demonstrating that iron oxide-gold nanoparticles produced by aqueous synthesis do not require an ideal core-shell structure for biological activity in cell labeling and targeting applications.

  5. Peptide-functionalized iron oxide magnetic nanoparticle for gold mining

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wei-Zheng; Cetinel, Sibel; Sharma, Kumakshi; Borujeny, Elham Rafie; Montemagno, Carlo, E-mail: montemag@ualberta.ca [Ingenuity Lab, 1-070C (Canada)

    2017-02-15

    Here, we present our work on preparing a novel nanomaterial composed of inorganic binding peptides and magnetic nanoparticles for inorganic mining. Two previously selected and well-characterized gold-binding peptides from cell surface display, AuBP1 and AuBP2, were exploited. This nanomaterial (AuBP-MNP) was designed to fulfill the following two significant functions: the surface conjugated gold-binding peptide will recognize and selectively bind to gold, while the magnetic nano-sized core will respond and migrate according to the applied external magnetic field. This will allow the smart nanomaterial to mine an individual material (gold) from a pool of mixture, without excessive solvent extraction, filtration, and concentration steps. The working efficiency of AuBP-MNP was determined by showing a dramatic reduction of gold nanoparticle colloid concentration, monitored by spectroscopy. The binding kinetics of AuBP-MNP onto the gold surface was determined using surface plasmon resonance (SPR) spectroscopy, which exhibits around 100 times higher binding kinetics than peptides alone. The binding capacity of AuBP-MNP was demonstrated by a bench-top mining test with gold microparticles.

  6. Supercritical CO2-Assisted Spray Drying of Strawberry-Like Gold-Coated Magnetite Nanocomposites in Chitosan Powders for Inhalation

    Directory of Open Access Journals (Sweden)

    Marta C. Silva

    2017-01-01

    Full Text Available Lung cancer is one of the leading causes of death worldwide. Therefore, it is of extreme importance to develop new systems that can deliver anticancer drugs into the site of action when initiating a treatment. Recently, the use of nanotechnology and particle engineering has enabled the development of new drug delivery platforms for pulmonary delivery. In this work, POXylated strawberry-like gold-coated magnetite nanocomposites and ibuprofen (IBP were encapsulated into a chitosan matrix using Supercritical Assisted Spray Drying (SASD. The dry powder formulations showed adequate morphology and aerodynamic performances (fine particle fraction 48%–55% and aerodynamic diameter of 2.6–2.8 µm for deep lung deposition through the pulmonary route. Moreover, the release kinetics of IBP was also investigated showing a faster release of the drug at pH 6.8, the pH of lung cancer. POXylated strawberry-like gold-coated magnetite nanocomposites proved to have suitable sizes for cellular internalization and their fluorescent capabilities enable their future use in in vitro cell based assays. As a proof-of-concept, the reported results show that these nano-in-micro formulations could be potential drug vehicles for pulmonary administration.

  7. Study of the Cd (II) removal in the presence of methyl orange with a natural zeolite conditioned with iron nanoparticles

    International Nuclear Information System (INIS)

    Xingu C, E. G.

    2015-01-01

    This work presents a study on the removal of cadmium and/or methyl-orange dye in aqueous solution, using natural zeolite clinoptilolite, as sodium homo-ionized and impregnated with iron nanoparticles. Iron nanoparticles were synthesized in the presence of the zeolite by chemical reduction. The evaluation of the removal ability was performed in a monocomponent (cadmium or methyl-orange dye) system by varying the contact time and its initial concentration. Removal capacity in a bi-component (cadmium and methyl orange) system was also studied while varying their concentrations. The characterization of the zeolites, before and after the sorption process, was carried out using several analytical techniques. The characteristics of zeolite clinoptilolite and iron particles were observed by scanning electron microscopy. The iron particles showed diameter sizes between 60 and 200 nm, localized on the surface of the zeolite. By IR spectroscopy no structural changes were detected for any of the treatments made to the zeolitic materials. By X-ray diffraction the clinoptilolite crystalline phase was mainly identified, however, it failed to detect any phase of iron in the zeolite impregnated with iron nanoparticles. Moessbauer spectroscopy indeed detected the impregnated iron phase as iron borides. The homo-ionized and iron nanoparticles impregnated zeolite showed no change in the specific surface area, or the isoelectric point, their values were 22.3 m 2 /g and ph 9.8, respectively. However, whereas the active site density for the homo-ionized zeolite was 2.87 sites/nm 2 , for iron nanoparticles impregnated zeolite was 20.32 sites/nm 2 . As a result of the analysis of the isotherms of cadmium, the maximum sorption capacity of the homo-ionized zeolite was 35.03 mg/g and for the iron nanoparticles impregnated zeolite was 36.43 mg/g. These maximum sorption capacities represent up to 85% of removed cadmium from concentrations of 50 to 600 mg/L. For the removal of methyl orange dye

  8. Iron nanoparticles prepared from natural ferrihydrite precursors: kinetics and properties

    International Nuclear Information System (INIS)

    Natural ferrihydrite was used as the precursors for the preparation of the nanocrystalline alpha-Fe powder using heat treatment in hydrogen atmosphere. Transformation temperatures were estimated from the temperature dependences of magnetic moment. Structure and phase composition of the precursors and the final powders were characterized by X-ray diffraction and Mössbauer spectroscopy. Magnetic properties were characterized according to hysteresis loop parameters. The kinetics of the transformation was described using Avrami relation applied on the data of the isothermal time dependence of magnetic moment measurements and subsequently the activation enthalpy of transformation was estimated using Arrhenius plots of their parameters. Comparison of the changes of activation enthalpies derived from a different temperature ranges indicates effects of different processes on formation of alpha-Fe nanoparticles.

  9. A predictive model of iron oxide nanoparticles flocculation tuning Z-potential in aqueous environment for biological application

    International Nuclear Information System (INIS)

    Baldassarre, Francesca; Cacciola, Matteo; Ciccarella, Giuseppe

    2015-01-01

    Iron oxide nanoparticles are the most used magnetic nanoparticles in biomedical and biotechnological field because of their nontoxicity respect to the other metals. The investigation of iron oxide nanoparticles behaviour in aqueous environment is important for the biological applications in terms of polydispersity, mobility, cellular uptake and response to the external magnetic field. Iron oxide nanoparticles tend to agglomerate in aqueous solutions; thus, the stabilisation and aggregation could be modified tuning the colloids physical proprieties. Surfactants or polymers are often used to avoid agglomeration and increase nanoparticles stability. We have modelled and synthesised iron oxide nanoparticles through a co-precipitation method, in order to study the influence of surfactants and coatings on the aggregation state. Thus, we compared experimental results to simulation model data. The change of Z-potential and the clusters size were determined by Dynamic Light Scattering. We developed a suitable numerical model to predict the flocculation. The effects of Volume Mean Diameter and fractal dimension were explored in the model. We obtained the trend of these parameters tuning the Z-potential. These curves matched with the experimental results and confirmed the goodness of the model. Subsequently, we exploited the model to study the influence of nanoparticles aggregation and stability by Z-potential and external magnetic field. The highest Z-potential is reached up with a small external magnetic influence, a small aggregation and then a high suspension stability. Thus, we obtained a predictive model of Iron oxide nanoparticles flocculation that will be exploited for the nanoparticles engineering and experimental setup of bioassays

  10. Mechanisms of Iron Uptake from Ferric Phosphate Nanoparticles in Human Intestinal Caco-2 Cells

    Directory of Open Access Journals (Sweden)

    Antonio Perfecto

    2017-04-01

    Full Text Available Food fortification programs to reduce iron deficiency anemia require bioavailable forms of iron that do not cause adverse organoleptic effects. Rodent studies show that nano-sized ferric phosphate (NP-FePO4 is as bioavailable as ferrous sulfate, but there is controversy over the mechanism of absorption. We undertook in vitro studies to examine this using a Caco-2 cell model and simulated gastrointestinal (GI digestion. Supernatant iron concentrations increased inversely with pH, and iron uptake into Caco-2 cells was 2–3 fold higher when NP-FePO4 was digested at pH 1 compared to pH 2. The size and distribution of NP-FePO4 particles during GI digestion was examined using transmission electron microscopy. The d50 of the particle distribution was 413 nm. Using disc centrifugal sedimentation, a high degree of agglomeration in NP-FePO4 following simulated GI digestion was observed, with only 20% of the particles ≤1000 nm. In Caco-2 cells, divalent metal transporter-1 (DMT1 and endocytosis inhibitors demonstrated that NP-FePO4 was mainly absorbed via DMT1. Small particles may be absorbed by clathrin-mediated endocytosis and micropinocytosis. These findings should be considered when assessing the potential of iron nanoparticles for food fortification.

  11. Influence of the aggregation, concentration, and viscosity on the nanomagnetism of iron oxide nanoparticle colloids for magnetic hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, David; Camarero, Julio; Ortega, Daniel; Teran, Francisco J., E-mail: francisco.teran@imdea.org [Ciudad Universitaria de Cantoblanco, IMDEA Nanociencia (Spain)

    2015-03-15

    Iron oxide nanoparticles have become ubiquitous in many biomedical applications, acting as core elements in an increasing number of therapeutic and diagnostic modalities. These applications mainly rely on their static and dynamic magnetic properties, through which they can be remotely actuated. However, little attention has been paid to understand the variation of the magnetic response of nanoparticles inside cells or tissues, despite of the remarkable changes reported to date. In this article, we provide some hints to analyze the influence of the biological matrix on the magnetism of iron oxide nanoparticles. To this aim, we propose the assessment of the heating efficiency of magnetic colloids against nanoparticle aggregation, concentration, and viscosity in order to mimic the fate of nanoparticles upon cell internalization.

  12. Influence of the aggregation, concentration, and viscosity on the nanomagnetism of iron oxide nanoparticle colloids for magnetic hyperthermia

    International Nuclear Information System (INIS)

    Cabrera, David; Camarero, Julio; Ortega, Daniel; Teran, Francisco J.

    2015-01-01

    Iron oxide nanoparticles have become ubiquitous in many biomedical applications, acting as core elements in an increasing number of therapeutic and diagnostic modalities. These applications mainly rely on their static and dynamic magnetic properties, through which they can be remotely actuated. However, little attention has been paid to understand the variation of the magnetic response of nanoparticles inside cells or tissues, despite of the remarkable changes reported to date. In this article, we provide some hints to analyze the influence of the biological matrix on the magnetism of iron oxide nanoparticles. To this aim, we propose the assessment of the heating efficiency of magnetic colloids against nanoparticle aggregation, concentration, and viscosity in order to mimic the fate of nanoparticles upon cell internalization

  13. Direct synthesis of magnetite nanoparticles from iron(II) carboxymethylcellulose and their performance as NMR contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Gomes da Silva, Delmarcio; Hiroshi Toma, Sergio; Menegatti de Melo, Fernando [Instituto de Química, Universidade de São Paulo, São Paulo, SP (Brazil); Carvalho, Larissa Vieira C.; Magalhães, Alvicler; Sabadini, Edvaldo [Instituto de Química, Universidade Estadual de Campinas – UNICAMP, Campinas, SP (Brazil); Domingues dos Santos, Antônio [Instituto de Física, Universidade de São Paulo, São Paulo, SP (Brazil); Araki, Koiti [Instituto de Química, Universidade de São Paulo, São Paulo, SP (Brazil); Toma, Henrique E., E-mail: henetoma@iq.usp.br [Instituto de Química, Universidade de São Paulo, São Paulo, SP (Brazil)

    2016-01-01

    Iron(II) carboxymethylcellulose (CMC) has been successfully employed in the synthesis of hydrophylic magnetite nanoparticles stabilized with a biopolymer coating, aiming applications in NMR imaging. The new method encompasses a convenient one-step synthetic procedure, allowing a good size control and yielding particles of about 10 nm (core size). In addition to the biocompatibility, the nanoparticles have promoted a drastic reduction in the transverse relaxation time (T{sub 2}) of the water protons. The relaxivity rates have been investigated as a function of the nanoparticles concentration, showing a better performance in relation to the common NMR contrast agents available in the market. - Highlights: • Stable, hydrophylic magnetic nanoparticles have been obtained. • Direct use of iron(II) carboxymethylcellulose improves the synthesis. • The magnetic nanoparticles exhibit high spin–spin relaxivity. • The particles promote dark contrast by decreasing the T{sub 2} relaxation time.

  14. Water dispersible superparamagnetic Cobalt iron oxide nanoparticles for magnetic fluid hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Salunkhe, Ashwini B. [Centre for advanced materials research, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Soft matter and molecular biophysics group, Department of Applied Physics, University of Santiago de Compostela, Santiago de Compostela (Spain); Khot, Vishwajeet M. [Department of Physics and Astronomy, University College London (United Kingdom); Ruso, Juan M. [Soft matter and molecular biophysics group, Department of Applied Physics, University of Santiago de Compostela, Santiago de Compostela (Spain); Patil, S.I., E-mail: patil@physics.unipune.ac.in [Centre for advanced materials research, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

    2016-12-01

    Superparamagnetic nanoparticles of Cobalt iron oxide (CoFe{sub 2}O{sub 4}) are synthesized chemically, and dispersed in an aqueous suspension for hyperthermia therapy application. Different parameters such as magnetic field intensity, particle concentration which regulates the competence of CoFe{sub 2}O{sub 4} nanoparticle as a heating agents in hyperthermia are investigated. Specific absorption rate (SAR) decreases with increase in the particle concentration and increases with increase in applied magnetic field intensity. Highest value of SAR is found to be 91.84 W g{sup −1} for 5 mg. mL{sup −1} concentration. Oleic acid conjugated polyethylene glycol (OA-PEG) coated CoFe{sub 2}O{sub 4} nanoparticles have shown superior cyto-compatibility over uncoated nanoparticles to L929 mice fibroblast cell lines for concentrations below 2 mg. mL{sup −1}. Present work provides the underpinning for the use of CoFe{sub 2}O{sub 4} nanoparticles as a potential heating mediator for magnetic fluid hyperthermia. - Highlights: • Superparamagnetic, water dispersible CoFe{sub 2}O{sub 4} NPs were synthesized by simple and cost effective Co precipitation route. • Effect of coating on various physical and chemical properties of CoFe{sub 2}O{sub 4} NPs were studied. • The effect of coating on induction heating as well as biocompatibility of NPs were studied.

  15. Self-assembled iron oxide nanoparticle multilayer: x-ray and polarized neutron reflectivity.

    Science.gov (United States)

    Mishra, D; Benitez, M J; Petracic, O; Badini Confalonieri, G A; Szary, P; Brüssing, F; Theis-Bröhl, K; Devishvili, A; Vorobiev, A; Konovalov, O; Paulus, M; Sternemann, C; Toperverg, B P; Zabel, H

    2012-02-10

    We have investigated the structure and magnetism of self-assembled, 20 nm diameter iron oxide nanoparticles covered by an oleic acid shell for scrutinizing their structural and magnetic correlations. The nanoparticles were spin-coated on an Si substrate as a single monolayer and as a stack of 5 ML forming a multilayer. X-ray scattering (reflectivity and grazing incidence small-angle scattering) confirms high in-plane hexagonal correlation and a good layering property of the nanoparticles. Using polarized neutron reflectivity we have also determined the long range magnetic correlations parallel and perpendicular to the layers in addition to the structural ones. In a field of 5 kOe we determine a magnetization value of about 80% of the saturation value. At remanence the global magnetization is close to zero. However, polarized neutron reflectivity reveals the existence of regions in which magnetic moments of nanoparticles are well aligned, while losing order over longer distances. These findings confirm that in the nanoparticle assembly the magnetic dipole-dipole interaction is rather strong, dominating the collective magnetic properties at room temperature.

  16. Strategies to optimize the biocompatibility of iron oxide nanoparticles – “SPIONs safe by design”

    International Nuclear Information System (INIS)

    Janko, Christina; Zaloga, Jan; Pöttler, Marina; Dürr, Stephan

    2017-01-01

    Various nanoparticle systems have been developed for medical applications in recent years. For constant improvement of efficacy and safety of nanoparticles, a close interdisciplinary interplay between synthesis, physicochemical characterizations and toxicological investigations is urgently needed. Based on combined toxicological data, we follow a “safe-by design” strategy for our superparamagnetic iron oxide nanoparticles (SPION). Using complementary interference-free toxicological assay systems, we initially identified agglomeration tendencies in physiological fluids, strong uptake by cells and improvable biocompatibility of lauric acid (LA)-coated SPIONs (SPION LA ). Thus, we decided to further stabilize those particles by an artificial protein corona consisting of serum albumin. This approach finally lead to increased colloidal stability, augmented drug loading capacity and improved biocompatibility in previous in vitro assays. Here, we show in whole blood ex vivo and on isolated red blood cells (RBC) that a protein corona protects RBCs from hemolysis by SPIONs. - Highlights: • Comparison of hemolytic properties between two SPION systems (with and without protein corona). • Protein corona increases the colloidal stability and hemocompatibility of SPIONs. • Close interaction between nanoparticle synthesis, physicochemical characterization and toxicology enables nanoparticle optimization (“safe by design”).

  17. Strategies to optimize the biocompatibility of iron oxide nanoparticles – “SPIONs safe by design”

    Energy Technology Data Exchange (ETDEWEB)

    Janko, Christina, E-mail: christina.janko@uk-erlangen.de [Department of Otorhinolaryngology, Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius-Stiftung Professorship, University Hospital Erlangen, Glückstraße 10a, Erlangen, 91054 Germany (Germany); Zaloga, Jan, E-mail: jan.zaloga@uk-erlangen.de [Department of Otorhinolaryngology, Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius-Stiftung Professorship, University Hospital Erlangen, Glückstraße 10a, Erlangen, 91054 Germany (Germany); Pöttler, Marina, E-mail: marina.poettler@uk-erlangen.de [Department of Otorhinolaryngology, Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius-Stiftung Professorship, University Hospital Erlangen, Glückstraße 10a, Erlangen, 91054 Germany (Germany); Dürr, Stephan, E-mail: stephan.duerr@uk-erlangen.de [Department of Otorhinolaryngology, Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius-Stiftung Professorship, University Hospital Erlangen, Glückstraße 10a, Erlangen, 91054 Germany (Germany); Department of Otorhinolaryngology, Section of Phoniatrics & Pediatric Audiology, Head & Neck Surgery, University Hospital Erlangen, Bohlenplatz 21, Erlangen, 91054 Germany (Germany); and others

    2017-06-01

    Various nanoparticle systems have been developed for medical applications in recent years. For constant improvement of efficacy and safety of nanoparticles, a close interdisciplinary interplay between synthesis, physicochemical characterizations and toxicological investigations is urgently needed. Based on combined toxicological data, we follow a “safe-by design” strategy for our superparamagnetic iron oxide nanoparticles (SPION). Using complementary interference-free toxicological assay systems, we initially identified agglomeration tendencies in physiological fluids, strong uptake by cells and improvable biocompatibility of lauric acid (LA)-coated SPIONs (SPION{sup LA}). Thus, we decided to further stabilize those particles by an artificial protein corona consisting of serum albumin. This approach finally lead to increased colloidal stability, augmented drug loading capacity and improved biocompatibility in previous in vitro assays. Here, we show in whole blood ex vivo and on isolated red blood cells (RBC) that a protein corona protects RBCs from hemolysis by SPIONs. - Highlights: • Comparison of hemolytic properties between two SPION systems (with and without protein corona). • Protein corona increases the colloidal stability and hemocompatibility of SPIONs. • Close interaction between nanoparticle synthesis, physicochemical characterization and toxicology enables nanoparticle optimization (“safe by design”).

  18. Preparation of epidermal growth factor (EGF) conjugated iron oxide nanoparticles and their internalization into colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Creixell, Mar [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Department of Electronics, Faculty of Physics, University of Barcelona, Av. Diagonal 647, 08028 Barcelona (Spain); Herrera, Adriana P.; Ayala, Vanessa; Latorre-Esteves, Magda [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Perez-Torres, Marianela [Department of Pharmaceutical Sciences, University of Puerto Rico-Medical Sciences Campus, PO Box 365067, San Juan, PR 00936 (Puerto Rico); Torres-Lugo, Madeline [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Rinaldi, Carlos, E-mail: carlos.rinaldi@upr.ed [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico)

    2010-08-15

    Epidermal growth factor (EGF) was conjugated with carboxymethyldextran (CMDx) coated iron oxide magnetic nanoparticles using carbodiimide chemistry to obtain magnetic nanoparticles that target the epidermal growth factor receptor (EGFR). Epidermal growth factor modified magnetic nanoparticles were colloidally stable when suspended in biological buffers such as PBS and cell culture media. Both targeted and non-targeted nanoparticles were incubated with CaCo-2 cancer cells, known to overexpress EGFR. Nanoparticle localization within the cell was visualized by confocal laser scanning microscopy and light microscopy using Prussian blue stain. Results showed that targeted magnetic nanoparticles were rapidly accumulated in both flask-shaped small vesicles and large circular endocytic structures. Internalization patterns suggest that both clathrin-dependent and clathrin-independent receptors mediated endocytosis mechanisms are responsible for nanoparticle internalization.

  19. Investigations of suspension stability of iron oxide nanoparticles using time-resolved UV–visible spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vikram, S.; Vasanthakumari, R. [B. S. Abdur Rahman University, Polymer Nanotechnology Centre (India); Tsuzuki, Takuya [Australian National University, Research School of Engineering, College of Engineering and Computer Science (Australia); Rangarajan, Murali, E-mail: r-murali@cb.amrita.edu [Amrita University, Center of Excellence in Advanced Materials and Green Technologies, Amrita School of Engineering Coimbatore (India)

    2016-09-15

    This study examines the suspension stability of iron oxide nanoparticles of different sizes, magnetic susceptibility, and saturation magnetization over long time scales in dilute systems using time-resolved UV–visible spectroscopy. The effects of citric acid as a chelating agent and applied external magnetic field are also studied. UV–visible spectra are obtained at different times for citric-acid-stabilized nanoparticles dispersed in water, and the peak absorbance is tracked with time, in the presence and absence of external magnetic fields. It is seen that the nanoparticles sediment slowly even in the absence of chain formation, with the phenomenon occurring in two-to-three regimes for the systems studied. Sedimentation exhibits either exponential or power-law behavior of maximum absorbance with time. In the dilute dispersions studied, thermal dispersion is about two orders of magnitude stronger than van der Waals interactions, and chain formation is not easy. Yet, it is likely that local anisotropic structures of the nanoparticles form, through which the attractive interactions result in sedimentation. Citric acid gradually stabilizes the aggregating particles; after an initial faster sedimentation, electrostatic repulsion causes the particles to segregate, as observed by a linear increase in the concentration of the nanoparticles at long times. In the presence of magnetic field, stabilization effects are significantly reduced. It is seen that though the attractive force between the nanoparticles and the external field is smaller than Brownian forces, together with van der Waals interactions, these attractive forces likely act as directing agents facilitating sedimentation. This study demonstrates that aggregation-induced sedimentation of magnetic nanoparticles is likely to play a significant role in magnetic drug targeting even when the particles are stabilized with chelating agents.Graphical abstract.

  20. Investigations of suspension stability of iron oxide nanoparticles using time-resolved UV–visible spectroscopy

    International Nuclear Information System (INIS)

    Vikram, S.; Vasanthakumari, R.; Tsuzuki, Takuya; Rangarajan, Murali

    2016-01-01

    This study examines the suspension stability of iron oxide nanoparticles of different sizes, magnetic susceptibility, and saturation magnetization over long time scales in dilute systems using time-resolved UV–visible spectroscopy. The effects of citric acid as a chelating agent and applied external magnetic field are also studied. UV–visible spectra are obtained at different times for citric-acid-stabilized nanoparticles dispersed in water, and the peak absorbance is tracked with time, in the presence and absence of external magnetic fields. It is seen that the nanoparticles sediment slowly even in the absence of chain formation, with the phenomenon occurring in two-to-three regimes for the systems studied. Sedimentation exhibits either exponential or power-law behavior of maximum absorbance with time. In the dilute dispersions studied, thermal dispersion is about two orders of magnitude stronger than van der Waals interactions, and chain formation is not easy. Yet, it is likely that local anisotropic structures of the nanoparticles form, through which the attractive interactions result in sedimentation. Citric acid gradually stabilizes the aggregating particles; after an initial faster sedimentation, electrostatic repulsion causes the particles to segregate, as observed by a linear increase in the concentration of the nanoparticles at long times. In the presence of magnetic field, stabilization effects are significantly reduced. It is seen that though the attractive force between the nanoparticles and the external field is smaller than Brownian forces, together with van der Waals interactions, these attractive forces likely act as directing agents facilitating sedimentation. This study demonstrates that aggregation-induced sedimentation of magnetic nanoparticles is likely to play a significant role in magnetic drug targeting even when the particles are stabilized with chelating agents.Graphical abstract

  1. Functional investigations on embryonic stem cells labeled with clinically translatable iron oxide nanoparticles

    Science.gov (United States)

    Liu, Jing; Wang, Liqin; Cao, Jianbo; Huang, Yue; Lin, Yu; Wu, Xiaoyun; Wang, Zhiyong; Zhang, Fan; Xu, Xiuqin; Liu, Gang

    2014-07-01

    Stem cell based therapies offer significant potential in the field of regenerative medicine. The development of superparamagnetic iron oxide (SPIO) nanoparticle labeling and magnetic resonance imaging (MRI) have been increasingly used to track the transplanted cells, enabling in vivo determination of cell fate. However, the impact of SPIO-labeling on the cell phenotype and differentiation capacity of embryonic stem cells (ESCs) remains unclear. In this study, we wrapped SPIO nanoparticles with stearic acid grafted PEI600, termed as Stearic-LWPEI-SPIO, to generate efficient and non-toxic ESC labeling tools. Our results showed that efficient labeling of ESCs at an optimized low dosage of Stearic-LWPEI-SPIO nanoparticles did not alter the differentiation and self-renewal properties of ESCs. The localization of the transplanted ESCs observed by MRI correlated well with histological studies. These findings demonstrate that Stearic-LWPEI-SPIO nanoparticles have potential to be clinically translatable MRI probes and may enable non-invasive in vivo tracking of ESCs in experimental and clinical settings during cell-based therapies.Stem cell based therapies offer significant potential in the field of regenerative medicine. The development of superparamagnetic iron oxide (SPIO) nanoparticle labeling and magnetic resonance imaging (MRI) have been increasingly used to track the transplanted cells, enabling in vivo determination of cell fate. However, the impact of SPIO-labeling on the cell phenotype and differentiation capacity of embryonic stem cells (ESCs) remains unclear. In this study, we wrapped SPIO nanoparticles with stearic acid grafted PEI600, termed as Stearic-LWPEI-SPIO, to generate efficient and non-toxic ESC labeling tools. Our results showed that efficient labeling of ESCs at an optimized low dosage of Stearic-LWPEI-SPIO nanoparticles did not alter the differentiation and self-renewal properties of ESCs. The localization of the transplanted ESCs observed by MRI

  2. Evaluation of umbilical cord mesenchymal stem cells labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-Lysine

    International Nuclear Information System (INIS)

    Sibov, Tatiana Tais; Mamani, Javier Bustamante; Pavon, Lorena Favaro; Cardenas, Walter Humberto; Gamarra, Lionel Fernel; Miyaki, Liza Aya Mabuchi; Marti, Luciana Cavalheiro; Sardinha, Luiz Roberto; Oliveira, Daniela Mara de

    2012-01-01

    Objective: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. Methods: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37 deg C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. Results: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/ dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide

  3. Formation of crystalline nanoparticles by iron binding to pentapeptide (Asp-His-Thr-Lys-Glu) from egg white hydrolysates.

    Science.gov (United States)

    Sun, Na; Cui, Pengbo; Li, Dongmei; Jin, Ziqi; Zhang, Shuyu; Lin, Songyi

    2017-09-20

    A novel peptide from egg white, Asp-His-Thr-Lys-Glu (DHTKE), contains specific amino acids associated with iron binding. The present study aims to better understand the molecular basis of interactions between the DHTKE peptide and iron ions. The ultraviolet-visible and fluorescence spectra indicate an interaction between the DHTKE peptide and iron ions, which leads to the formation of a DHTKE-iron complex. Notably, Asp, Glu, His, and Lys in the DHTKE peptide play crucial roles in the formation of the DHTKE-iron complex, and the iron-binding site of the DHTKE peptide corresponds primarily to the amide and carboxyl groups. The DHTKE peptide can bind iron ions in a 1 : 2 ratio with a binding constant of 1.312 × 10 5 M -1 . Moreover, the DHTKE-iron complex belongs to thermodynamically stable nanoparticles that are present in the crystalline structure, which might be attributed to peptide folding induced by iron binding. Meanwhile, the DHTKE-iron complex exhibits a relatively high iron-releasing percentage and exerts excellent solubility in the human gastrointestinal tract in vitro. This suggests a potential application of peptides containing Asp, Glu, His, or Lys residues as potential iron supplements.

  4. Self-Assembled Lipid Nanoparticles for Oral Delivery of Heparin-Coated Iron Oxide Nanoparticles for Theranostic Purposes.

    Science.gov (United States)

    Truzzi, Eleonora; Bongio, Chiara; Sacchetti, Francesca; Maretti, Eleonora; Montanari, Monica; Iannuccelli, Valentina; Vismara, Elena; Leo, Eliana

    2017-06-09

    Recently, solid lipid nanoparticles (SLNs) have attracted increasing attention owing to their potential as an oral delivery system, promoting intestinal absorption in the lymphatic circulation which plays a role in disseminating metastatic cancer cells and infectious agents throughout the body. SLN features can be exploited for the oral delivery of theranostics. Therefore, the aim of this work was to design and characterise self-assembled lipid nanoparticles (SALNs) to encapsulate and stabilise iron oxide nanoparticles non-covalently coated with heparin (Fe@hepa) as a model of a theranostic tool. SALNs were characterised for physico-chemical properties (particle size, surface charge, encapsulation efficiency, in vitro stability, and heparin leakage), as well as in vitro cytotoxicity by methyl thiazole tetrazolium (MTT) assay and cell internalisation in CaCo-2, a cell line model used as an indirect indication of intestinal lymphatic absorption. SALNs of about 180 nm, which are stable in suspension and have a high encapsulation efficiency (>90%) were obtained. SALNs were able to stabilise the heparin coating of Fe@hepa, which are typically unstable in physiological environments. Moreover, SALNs-Fe@hepa showed no cytotoxicity, although their ability to be internalised into CaCo-2 cells was highlighted by confocal microscopy analysis. Therefore, the results indicated that SALNs can be considered as a promising tool to orally deliver theranostic Fe@hepa into the lymphatic circulation, although further in vivo studies are needed to comprehend further potential applications.

  5. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type

    DEFF Research Database (Denmark)

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.

    2015-01-01

    Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero v...... for the PCB dechlorination, and this cell allowed a uniform distribution of the nanoparticles in the soil, while there was iron accumulation in the injection reservoir in the three-compartment cell....... valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron...... nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used...

  6. Neural Induction Potential and MRI of ADSCs Labeled Cationic Superparamagnetic Iron Oxide Nanoparticle In Vitro

    Directory of Open Access Journals (Sweden)

    Weiqiong Ma

    2018-01-01

    Full Text Available Magnetic resonance imaging (MRI combined with contrast agents is believed to be useful for stem cell tracking in vivo, and the aim of this research was to investigate the biosafety and neural induction of SD rat-originated adipose derived stem cells (ADSCs using cationic superparamagnetic iron oxide (SPIO nanoparticle which was synthesized by the improved polyol method, in order to allow visualization using in vitro MRI. The scan protocols were performed with T2-mapping sequence; meanwhile, the ultrastructure of labeled cells was observed by transmission electron microscopy (TEM while the iron content was measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES. After neural induction, nestin and NSE (neural markers were obviously expressed. In vitro MRI showed that the cationic PEG/PEI-modified SPIO nanoparticles could achieve great relaxation performance and favourable longevity. And the ICP-AES quantified the lowest iron content that could be detected by MRI as 1.56~1.8 pg/cell. This study showed that the cationic SPIO could be directly used to label ADSCs, which could then inductively differentiate into nerve and be imaged by in vitro MRI, which would exhibit important guiding significance for the further in vivo MRI towards animal models with neurodegenerative disorders.

  7. Synthesis, Characterization, and Toxicity Evaluation of Dextran-Coated Iron Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Mihaela Balas

    2017-02-01

    Full Text Available We report the synthesis of dextran-coated iron oxide magnetic nanoparticles (DIO-NPs with spherical shape and uniform size distribution as well as their accumulation and toxic effects on Jurkat cells up to 72 h. The characterization of dextran-coated maghemite nanoparticles was done by X-ray diffraction and dynamic light scattering analyses, transmission electron microscopy imaging, attenuated total reflectance Fourier transform infrared (ATR-FTIR spectroscopy, magnetic hysteresis, and relaxometry measurements. The quantification of DIO-NPs intracellular uptake showed a progressive accumulation of iron as a function of time and dose accompanied by additional lysosome formation and an increasing darkening exhibited by a magnetic resonance imaging (MRI scanner. The cytotoxicity assays revealed a decrease of cell viability and a loss of membrane integrity in a time- and dose-dependent manner. Exposure to DIO-NPs determined an increase in reactive oxygen species level up to 72 h. In the first two days of exposure, the level of reduced glutathione decreased and the amount of malondyaldehyde increased, but at the end of the experiment, their concentrations returned to control values. These nanoparticles could be used as contrast agents for MRI but several parameters concerning their interaction with the cells should be taken into consideration for a safe utilization.

  8. Single-step gas phase synthesis of stable iron aluminide nanoparticles with soft magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Vernieres, Jerome, E-mail: Jerome.vernieres@oist.jp; Benelmekki, Maria; Kim, Jeong-Hwan; Grammatikopoulos, Panagiotis; Diaz, Rosa E. [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Bobo, Jean-François [Centre d’Elaboration de Materiaux et d’Etudes Structurales (CEMES), 29 rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France); Sowwan, Mukhles, E-mail: Mukhles@oist.jp [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Nanotechnology Research Laboratory, Al-Quds University, P.O. Box 51000, East Jerusalem, Palestine (Country Unknown)

    2014-11-01

    Soft magnetic alloys at the nanoscale level have long generated a vivid interest as candidate materials for technological and biomedical purposes. Consequently, controlling the structure of bimetallic nanoparticles in order to optimize their magnetic properties, such as high magnetization and low coercivity, can significantly boost their potential for related applications. However, traditional synthesis methods stumble upon the long standing challenge of developing true nanoalloys with effective control over morphology and stability against oxidation. Herein, we report on a single-step approach to the gas phase synthesis of soft magnetic bimetallic iron aluminide nanoparticles, using a versatile co-sputter inert gas condensation technique. This method allowed for precise morphological control of the particles; they consisted of an alloy iron aluminide crystalline core (DO{sub 3} phase) and an alumina shell, which reduced inter-particle interactions and also prevented further oxidation and segregation of the bimetallic core. Remarkably, the as-deposited alloy nanoparticles show interesting soft magnetic properties, in that they combine a high saturation magnetization (170 emu/g) and low coercivity (less than 20 Oe) at room temperature. Additional functionality is tenable by modifying the surface of the particles with a polymer, to ensure their good colloidal dispersion in aqueous environments.

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

    Science.gov (United States)

    Hachani, Roxanne; Lowdell, Mark; Birchall, Martin; Hervault, Aziliz; Mertz, Damien; Begin-Colin, Sylvie; Thanh, Nguyen Thi Kim

    2016-02-14

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

  10. Size dependence of the magnetic relaxation and specific power absorption in iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Lima, E. [CONICET and Instituto de Nanociencia y Nanotecnologia and Centro Atomico Bariloche (Argentina); Torres, T. E. [University of Zaragoza, Instituto de Nanociencia de Aragon (INA) and Departamento de Fisica de la Materia Condensada and Laboratorio de Microscopias Avanzadas (LMA) (Spain); Rossi, L. M. [Instituto de Quimica, Universidade de Sao Paulo (Brazil); Rechenberg, H. R. [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Berquo, T. S. [Institute of Rock Magnetism, University of Minnesota (United States); Ibarra, A. [University of Zaragoza, INA and LMA (Spain); Marquina, C. [CSIC, Universidad de Zaragoza, Departamento de Fisica de la Materia Condensada and Instituto de Ciencia de Materiales de Aragon (ICMA) (Spain); Ibarra, M. R. [University of Zaragoza, INA and Departamento de Fisica de la Materia Condensada and LMA (Spain); Goya, G. F., E-mail: goya@unizar.es [University of Zaragoza, INA and Departamento de Fisica de la Materia Condensada (Spain)

    2013-05-15

    In this study, magnetic and power absorption properties of a series of iron oxide nanoparticles with average sizes Left-Pointing-Angle-Bracket d Right-Pointing-Angle-Bracket ranging from 3 to 23 nm were reported. The nanoparticles were prepared by thermal decomposition of Iron(III) acetylacetonate in organic media. From the careful characterization of the magnetic and physicochemical properties of these samples, the specific power absorption (SPA) values experimentally found were numerically reproduced, as well as their dependence with particle size, using a simple model of Brownian and Neel relaxation at room temperature. SPA experiments in ac magnetic fields (H{sub 0} = 13 kA/m and f = 250 kHz) indicated that the magnetic and rheological properties played a crucial role determining the heating efficiency at different conditions. A maximum SPA value of 344 W/g was obtained for a sample containing nanoparticles with Left-Pointing-Angle-Bracket d Right-Pointing-Angle-Bracket = 12 nm and dispersion {sigma} = 0.25. The observed SPA dependence with particle diameter and their magnetic parameters indicated that, for the size range and experimental conditions of f and H studied in this study, both Neel and Brown relaxation mechanisms are important to the heat generation observed.

  11. Synthesis and in vacuo deposition of iron oxide nanoparticles by microplasma-assisted decomposition of ferrocene

    International Nuclear Information System (INIS)

    Schaefer, Michael; Kumar, Ajay; Mohan Sankaran, R.; Schlaf, Rudy

    2014-01-01

    Microplasma-assisted gas-phase nucleation has emerged as an important new approach to produce high-purity, nanometer-sized, and narrowly dispersed particles. This study aims to integrate this technique with vacuum conditions to enable synthesis and deposition in an ultrahigh vacuum compatible environment. The ultimate goal is to combine nanoparticle synthesis with photoemission spectroscopy-based electronic structure analysis. Such measurements require in vacuo deposition to prevent surface contamination from sample transfer, which can be deleterious for nanoscale materials. A homebuilt microplasma reactor was integrated into an existing atomic layer deposition system attached to a surface science multi-chamber system equipped with photoemission spectroscopy. As proof-of-concept, we studied the decomposition of ferrocene vapor in the microplasma to synthesize iron oxide nanoparticles. The injection parameters were optimized to achieve complete precursor decomposition under vacuum conditions, and nanoparticles were successfully deposited. The stoichiometry of the deposited samples was characterized in situ using X-ray photoelectron spectroscopy indicating that iron oxide was formed. Additional transmission electron spectroscopy characterization allowed the determination of the size, shape, and crystal lattice of the particles, confirming their structural properties.

  12. Modeling of the laser pyrolysis process by means of the aerosol theory: Case of iron nanoparticles

    Science.gov (United States)

    Bomatí-Miguel, O.; Zhao, X. Q.; Martelli, S.; Di Nunzio, P. E.; Veintemillas-Verdaguer, S.

    2010-01-01

    Laser pyrolysis is a technique in which the interaction between a laser and a gaseous flow of precursors is used to obtain homogeneous nanoparticles. One of the main advantages of using this method is that it generates ultrafine powders in a continuous way with narrow particle-size distribution. The absence of surfactants of potential toxicity makes the product ideal for the preparation of colloidal dispersions for use in biomedical applications. It is of particular interest in the case of the iron nanoparticles due to their high magnetic response. In this paper, a simple coagulation model adapted from the theory of aerosol formation is successfully used in the modeling of the production of iron nanoparticles. The experimental conditions needed to maximize the productivity were obtained as a function of particle size. The main conclusion is that for the production of "large" particle-size nanomaterials (>20 nm), the ruling factors are the pressure and the carrier gas flux. However, the production of small particle-size nanomaterials (<20 nm) depends on the evaporation temperature of the precursor.

  13. Optimization of synthesis and peptization steps to obtain iron oxide nanoparticles with high energy dissipation rates

    Energy Technology Data Exchange (ETDEWEB)

    Mérida, Fernando [Deparment of Chemical Engineering, University of Puerto Rico, Mayagüez, P.O. Box 9046, Mayagüez, PR 00680 (United States); Chiu-Lam, Andreina [Department of Chemical Engineering, University of Florida, P.O. Box 116005, Gainesville, FL 32611-6005 (United States); Bohórquez, Ana C. [J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, P.O. Box 116131, Gainesville, FL 32611-6131 (United States); Maldonado-Camargo, Lorena [Department of Chemical Engineering, University of Florida, P.O. Box 116005, Gainesville, FL 32611-6005 (United States); Pérez, María-Eglée; Pericchi, Luis [Department of Mathematics, University of Puerto Rico, Río Piedras, P.O. Box 70377, San Juan, PR 00936-8377 (United States); Torres-Lugo, Madeline [Deparment of Chemical Engineering, University of Puerto Rico, Mayagüez, P.O. Box 9046, Mayagüez, PR 00680 (United States); Rinaldi, Carlos, E-mail: carlos.rinaldi@bme.ufl.edu [Department of Chemical Engineering, University of Florida, P.O. Box 116005, Gainesville, FL 32611-6005 (United States); J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, P.O. Box 116131, Gainesville, FL 32611-6131 (United States)

    2015-11-15

    Magnetic Fluid Hyperthermia (MFH) uses heat generated by magnetic nanoparticles exposed to alternating magnetic fields to cause a temperature increase in tumors to the hyperthermia range (43–47 °C), inducing apoptotic cancer cell death. As with all cancer nanomedicines, one of the most significant challenges with MFH is achieving high nanoparticle accumulation at the tumor site. This motivates development of synthesis strategies that maximize the rate of energy dissipation of iron oxide magnetic nanoparticles, preferable due to their intrinsic biocompatibility. This has led to development of synthesis strategies that, although attractive from the point of view of chemical elegance, may not be suitable for scale-up to quantities necessary for clinical use. On the other hand, to date the aqueous co-precipitation synthesis, which readily yields gram quantities of nanoparticles, has only been reported to yield sufficiently high specific absorption rates after laborious size selective fractionation. This work focuses on improvements to the aqueous co-precipitation of iron oxide nanoparticles to increase the specific absorption rate (SAR), by optimizing synthesis conditions and the subsequent peptization step. Heating efficiencies up to 1048 W/g{sub Fe} (36.5 kA/m, 341 kHz; ILP=2.3 nH m{sup 2} kg{sup −1}) were obtained, which represent one of the highest values reported for iron oxide particles synthesized by co-precipitation without size-selective fractionation. Furthermore, particles reached SAR values of up to 719 W/g{sub Fe} (36.5 kA/m, 341 kHz; ILP=1.6 nH m{sup 2} kg{sup −1}) when in a solid matrix, demonstrating they were capable of significant rates of energy dissipation even when restricted from physical rotation. Reduction in energy dissipation rate due to immobilization has been identified as an obstacle to clinical translation of MFH. Hence, particles obtained with the conditions reported here have great potential for application in nanoscale thermal

  14. Rapid pharmacokinetic and biodistribution studies using cholorotoxin-conjugated iron oxide nanoparticles: a novel non-radioactive method.

    Directory of Open Access Journals (Sweden)

    Michelle Jeung-Eun Lee

    2010-03-01

    Full Text Available Recent advances in nanotechnology have led to the development of biocompatible nanoparticles for in vivo molecular imaging and targeted therapy. Many nanoparticles have undesirable tissue distribution or unacceptably low serum half-lives. Pharmacokinetic (PK and biodistribution studies can help inform decisions determining particle size, coatings, or other features early in nanoparticle development. Unfortunately, these studies are rarely done in a timely fashion because many nanotechnology labs lack the resources and expertise to synthesize radioactive nanoparticles and evaluate them in mice.To address this problem, we developed an economical, radioactivity-free method for assessing serum half-life and tissue distribution of nanoparticles in mice. Iron oxide nanoparticles coated with chitosan and polyethylene glycol that utilize chlorotoxin as a targeting molecule have a serum half-life of 7-8 hours and the particles remain stable for extended periods of time in physiologic fluids and in vivo. Nanoparticles preferentially distribute to spleen and liver, presumably due to reticuloendothelial uptake. Other organs have very low levels of nanoparticles, which is ideal for imaging most cancers in the future. No acute toxicity was attributed to the nanoparticles.We report here a simple near-infrared fluorescence based methodology to assess PK properties of nanoparticles in order to integrate pharmacokinetic data into early nanoparticle design and synthesis. The nanoparticles tested demonstrate properties that are excellent for future clinical imaging strategies and potentially suitable for targeted therapy.

  15. Iron

    Science.gov (United States)

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  16. Toxicity assessment and comparison between two types of iron oxide nanoparticles in Mytilus galloprovincialis

    International Nuclear Information System (INIS)

    Taze, Chrysa; Panetas, Ioannis; Kalogiannis, Stavros; Feidantsis, Konstantinos; Gallios, George P.; Kastrinaki, Georgia; Konstandopoulos, Athanasios G.; Václavíková, Miroslava; Ivanicova, Lucia; Kaloyianni, Martha

    2016-01-01

    Highlights: • The impact of two types of iron oxide nanoparticles on the physiological status of mussels was studied. • Oxidative parameters significantly changed after 1, 3, 7 days of exposure. • The nanoparticles induced oxidative stress to the animals. • All the parameters measured could be applied in biomonitoring studies. - Abstract: Nanoparticles (NPs), due to their increased application and production, are being released into the environment with unpredictable impact on the physiology of marine organisms, as well as on entire ecosystems and upcoming effects on human health. The aim of the present study was to evaluate and compare the oxidative responses of the mussel Mytilus galloprovincialis after exposure to iron oxide NPs and to iron oxide NPs incorporated into zeolite for 1, 3 and 7 days. Our results showed that both effectors induced changes on animal physiology by causing oxidative stress in hemocytes of exposed mussels compared to control animals. This was shown by the significant increase in reactive oxygen species (ROS) production, protein carbonylation, lipid peroxidation, ubiquitin conjugates and DNA damage. In addition an increase in prooxidant levels as measured by the prooxidant-antioxidant balance (PAB) assay was observed in exposed mussels’ hemolymph. The results show that ROS, DNA damage, protein and lipid oxidation, ubiquitin conjugates and PAB could constitute, after further investigation, reliable biomarkers for the evaluation of pollution or other environmental stressors. In addition, more studies are needed in order to ensure the safety of these NPs on various biomedical applications, since it is critical to design NPs that they meet the demands of application without causing cellular toxicity.

  17. Toxicity assessment and comparison between two types of iron oxide nanoparticles in Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Taze, Chrysa; Panetas, Ioannis [Laboratory of Animal Physiology, Department of Zoology, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Kalogiannis, Stavros [Alexander Technological Educational Institution of Thessaloniki, Department of Nutrition and Dietetics, Thessaloniki (Greece); Feidantsis, Konstantinos [Laboratory of Animal Physiology, Department of Zoology, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Gallios, George P. [Laboratory of General & Inorganic Chemical Technology, School of Chemistry, Aristotle University, GR-54124 Thessaloniki (Greece); Kastrinaki, Georgia [Aerosol & Particle Technology Laboratory, CERTH/CPERI, P.O. Box 60361, 57001 Thessaloniki (Greece); Konstandopoulos, Athanasios G. [Aerosol & Particle Technology Laboratory, CERTH/CPERI, P.O. Box 60361, 57001 Thessaloniki (Greece); Department of Chemical Engineering, Aristotle University, PO. Box 1517, 54006 Thessaloniki (Greece); Václavíková, Miroslava; Ivanicova, Lucia [Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, SK-04001 Kosice (Slovakia); Kaloyianni, Martha, E-mail: kaloyian@bio.auth.gr [Laboratory of Animal Physiology, Department of Zoology, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2016-03-15

    Highlights: • The impact of two types of iron oxide nanoparticles on the physiological status of mussels was studied. • Oxidative parameters significantly changed after 1, 3, 7 days of exposure. • The nanoparticles induced oxidative stress to the animals. • All the parameters measured could be applied in biomonitoring studies. - Abstract: Nanoparticles (NPs), due to their increased application and production, are being released into the environment with unpredictable impact on the physiology of marine organisms, as well as on entire ecosystems and upcoming effects on human health. The aim of the present study was to evaluate and compare the oxidative responses of the mussel Mytilus galloprovincialis after exposure to iron oxide NPs and to iron oxide NPs incorporated into zeolite for 1, 3 and 7 days. Our results showed that both effectors induced changes on animal physiology by causing oxidative stress in hemocytes of exposed mussels compared to control animals. This was shown by the significant increase in reactive oxygen species (ROS) production, protein carbonylation, lipid peroxidation, ubiquitin conjugates and DNA damage. In addition an increase in prooxidant levels as measured by the prooxidant-antioxidant balance (PAB) assay was observed in exposed mussels’ hemolymph. The results show that ROS, DNA damage, protein and lipid oxidation, ubiquitin conjugates and PAB could constitute, after further investigation, reliable biomarkers for the evaluation of pollution or other environmental stressors. In addition, more studies are needed in order to ensure the safety of these NPs on various biomedical applications, since it is critical to design NPs that they meet the demands of application without causing cellular toxicity.

  18. Temephos Removal From Water Samples by Silver Modified Zero-Valent Iron Nanoparticles

    Directory of Open Access Journals (Sweden)

    Shiralipour

    2015-01-01

    Full Text Available Background Temephos is an organophosphate pesticide used as larvicide in the environment. Although not extremely hazardous, it can be risky for human health in the moderate concentrations. Objectives This study investigated the quantitative removal efficiency of temephos, an organophosphate pesticide, from contaminated water by silver-modified ZVINPs. In addition, the operational parameters affected on removal process were optimized. Materials and Methods In the current study, three water samples from different parts of Iran such as Ahvaz tap water, the Karoon River passing through Khoramshahr city, and the Caspian Sea were collected. A new method for effective removal of temephos from the sample solutions by silver modified zero-valent iron nanoparticles as an efficient adsorbent was introduced. Results For a typical solution in which temephos was removed about 21% by iron zero-valent nanoparticles, modification by silver improved removal method was up to about 99%. The required time for the complete removal of temephos was about eight minutes. Variation of pH and concentration of KNO3 as an electrolyte was considerably ineffective on the efficient temephos removal. Adsorption studies of the method were followed by Langmuir isotherm. Maximum temephos adsorption amount was 12.65 mg/g under optimal conditions. The proposed method was simple, fast and safe to treat temephos polluted waters. Preparation of the adsorbent was easy and removal time was short. Conclusions Briefly, the current study represents a novel method to eliminate temephos as an organophosphate compound from water samples with modified zero-valent iron nanoparticles.

  19. MRI based on iron oxide nanoparticles contrast agents: effect of oxidation state and architecture

    Science.gov (United States)

    Javed, Yasir; Akhtar, Kanwal; Anwar, Hafeez; Jamil, Yasir

    2017-11-01

    Iron oxide nanoparticles (IONPs) extensively employed beyond regenerative medicines to imaging disciplines because of their great constituents for magneto-responsive nano-systems. The unique superparamagnetic behavior makes IONPs very suitable for hyperthermia and imaging applications. From the last decade, versatile functionalization with surface capabilities, efficient contrast properties and biocompatibilities make IONPs an essential imaging contrast agent for magnetic resonance imaging (MRI). IONPs have shown signals for both longitudinal relaxation and transverse relaxation; therefore, negative contrast as well as dual contrast can be used for imaging in MRI. In the current review, we have focused on different oxidation state of iron oxides, i.e., magnetite, maghemite and hematite for their T1 and T2 contrast enhancement properties. We have also discussed different factors (synthesis protocols, biocompatibility, toxicity, architecture, etc.) that can affect the contrast properties of the IONPs. [Figure not available: see fulltext.

  20. Preparation and biodistribution of {sup 59}Fe-radiolabelled iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pospisilova, Martina, E-mail: martinapospisilova@gmail.com; Zapotocky, Vojtech; Nesporova, Kristina [Contipro a.s (Czech Republic); Laznicek, Milan; Laznickova, Alice [Charles University, Faculty of Pharmacy in Hradec Králové (Czech Republic); Zidek, Ondrej; Cepa, Martin; Vagnerova, Hana; Velebny, Vladimir [Contipro a.s (Czech Republic)

    2017-02-15

    We report on the {sup 59}Fe radiolabelling of iron oxide nanoparticle cores through post-synthetic isotope exchange ({sup 59}Fe-IONP{sub ex}) and precursor labelling ({sup 59}Fe-IONP{sub pre}). Scanning electron microscopy and dynamic light scattering measurements showed no impact of radiolabelling on nanoparticle size or morphology. While incorporation efficiencies of these methods are comparable—83 and 90% for precursor labelling and post-synthetic isotope exchange, respectively—{sup 59}Fe-IONP{sub pre} exhibited much higher radiochemical stability in citrated human plasma. Quantitative ex vivo biodistribution study of {sup 59}Fe-IONP{sub pre} coated with triethylene glycol was performed in Wistar rats. Following the intravenous administration, high {sup 59}Fe concentration was observed in the lung and the organs of the reticuloendothelial system such as the liver, the spleen and the femur.

  1. Synthesis of carboxyl superparamagnetic ultrasmall iron oxide (USPIO) nanoparticles by a novel flocculation-redispersion process

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Changming [Nano Biomedicine Research Center, Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Kou Geng [International Joint Cancer Institute, Second Military Medical University, Shanghai 200433 (China); Wang Xiaoliang [Nano Biomedicine Research Center, Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang Shuhui [International Joint Cancer Institute, Second Military Medical University, Shanghai 200433 (China); Gu Hongchen [Nano Biomedicine Research Center, Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200240 (China)], E-mail: hcgu@sjtu.edu.cn; Guo Yajun [International Joint Cancer Institute, Second Military Medical University, Shanghai 200433 (China)], E-mail: yjguo@smmu.edu.cn

    2009-09-15

    We report a novel flocculation-redispersion method to synthesize and purify the biocompatible superparamagnetic ultrasmall iron oxide (USPIO) nanoparticles coated with carboxyl dextran derivative. First, USPIO nanoparticles were synthesized and flocculated to form the large clusters through bridging effect of polyvinyl alcohol (PVA) during coprecipitation process. Then the flocculated USPIO was separated and purified from the solution conveniently through magnetic sedimentation. Finally, USPIO in the clusters were released again and well dispersed through electrostatic repelling effect of citric acid with the aid of ultrasonic. The dispersed carboxyl-functionalized USPIO was conjugated with the monoclonal antibodies. And it has been proved that the antibodies anchored on USPIO still retained their bioactivity after the conjugation. These results implied that the USPIO synthesized have good potential as active targeting molecular probe in biomedical application.

  2. Magnetic properties of iron oxide nanoparticles prepared by seeded-growth route

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, A., E-mail: anaespinosamr@gmail.com [Consejo Superior de Investigaciones Cientificas, Instituto de Ciencia de Materiales de Madrid (ICMM) (Spain); Munoz-Noval, A. [Consejo Superior de Investigaciones Cientificas, Instituto de Ceramica y Vidrio (ICV) (Spain); Garcia-Hernandez, M. [Consejo Superior de Investigaciones Cientificas, Instituto de Ciencia de Materiales de Madrid (ICMM) (Spain); Serrano, A. [Consejo Superior de Investigaciones Cientificas, Instituto de Ceramica y Vidrio (ICV) (Spain); Jimenez de la Morena, J. [Consejo Superior de Investigaciones Cientificas, Instituto de Ciencia de Materiales de Madrid (ICMM) (Spain); Figuerola, A. [Universitat de Barcelona, Departament de Quimica Inorganica i Institut de Nanociencia i Nanotecnologia (Spain); Quarta, A.; Pellegrino, T. [National Nanotechnology Laboratory of CNR-NANO (Italy); Wilhelm, C. [CNRS and Universite Paris Diderot, Laboratoire Matiere et Systemes Complexes (MSC), UMR 7057 (France); Garcia, M. A. [Consejo Superior de Investigaciones Cientificas, Instituto de Ceramica y Vidrio (ICV) (Spain)

    2013-04-15

    In this work we investigate the magnetic properties of iron oxide nanoparticles obtained by two-step synthesis (seeded-growth route) with sizes that range from 6 to 18 nm. The initial seeds result monocrystalline and exhibit ferromagnetic behavior with low saturation field. The subsequent growth of a shell enhances the anisotropy inducing magnetic frustration, and, consequently, reducing its magnetization. This increase in anisotropy occurs suddenly at a certain size ({approx}10 nm). Electronic and structural analysis with X-ray absorption spectroscopy indicates a step reduction in the oxidation state as the particle reaches 10 nm size while keeping its overall structure in spite of the magnetic polydispersity. The formation of antiphase magnetic boundaries due to island percolation in the growing shells is hypothesized to be the mechanism responsible of the magnetic behavior, as a direct consequence of the two-step synthesis route of the nanoparticles.

  3. Fabricating Water Dispersible Superparamagnetic Iron Oxide Nanoparticles for Biomedical Applications through Ligand Exchange and Direct Conjugation

    Directory of Open Access Journals (Sweden)

    Tina Lam

    2016-05-01

    Full Text Available Stable superparamagnetic iron oxide nanoparticles (SPIONs, which can be easily dispersed in an aqueous medium and exhibit high magnetic relaxivities, are ideal candidates for biomedical applications including contrast agents for magnetic resonance imaging. We describe a versatile methodology to render water dispersibility to SPIONs using tetraethylene glycol (TEG-based phosphonate ligands, which are easily introduced onto SPIONs by either a ligand exchange process of surface-anchored oleic-acid (OA molecules or via direct conjugation. Both protocols confer good colloidal stability to SPIONs at different NaCl concentrations. A detailed characterization of functionalized SPIONs suggests that the ligand exchange method leads to nanoparticles with better magnetic properties but higher toxicity and cell death, than the direct conjugation methodology.

  4. Macrophage membrane-coated iron oxide nanoparticles for enhanced photothermal tumor therapy

    Science.gov (United States)

    Meng, Qian-Fang; Rao, Lang; Zan, Minghui; Chen, Ming; Yu, Guang-Tao; Wei, Xiaoyun; Wu, Zhuhao; Sun, Yue; Guo, Shi-Shang; Zhao, Xing-Zhong; Wang, Fu-Bing; Liu, Wei

    2018-04-01

    Nanotechnology possesses the potential to revolutionize the diagnosis and treatment of tumors. The ideal nanoparticles used for in vivo cancer therapy should have long blood circulation times and active cancer targeting. Additionally, they should be harmless and invisible to the immune system. Here, we developed a biomimetic nanoplatform with the above properties for cancer therapy. Macrophage membranes were reconstructed into vesicles and then coated onto magnetic iron oxide nanoparticles (Fe3O4 NPs). Inherited from the Fe3O4 core and the macrophage membrane shell, the resulting Fe3O4@MM NPs exhibited good biocompatibility, immune evasion, cancer targeting and light-to-heat conversion capabilities. Due to the favorable in vitro and in vivo properties, biomimetic Fe3O4@MM NPs were further used for highly effective photothermal therapy of breast cancer in nude mice. Surface modification of synthetic nanomaterials with biomimetic cell membranes exemplifies a novel strategy for designing an ideal nanoplatform for translational medicine.

  5. Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

    International Nuclear Information System (INIS)

    Bloemen, Maarten; Brullot, Ward; Luong, Tai Thien; Geukens, Nick; Gils, Ann; Verbiest, Thierry

    2012-01-01

    Superparamagnetic iron oxide nanoparticles can provide multiple benefits for biomedical applications in aqueous environments such as magnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality water-dispersible nanoparticles around 10 nm in size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.

  6. Manganese doped-iron oxide nanoparticle clusters and their potential as agents for magnetic resonance imaging and hyperthermia

    KAUST Repository

    Casula, Maria F.

    2016-06-10

    A simple, one pot method to synthesize water-dispersible Mn doped iron oxide colloidal clusters constructed of nanoparticles arranged into secondary flower-like structures was developed. This method allows the successful incorporation and homogeneous distribution of Mn within the nanoparticle iron oxide clusters. The formed clusters retain the desired morphological and structural features observed for pure iron oxide clusters, but possess intrinsic magnetic properties that arise from Mn doping. They show distinct performance as imaging contrast agents and excellent characteristics as heating mediators in magnetic fluid hyperthermia. It is expected that the outcomes of this study will open up new avenues for the exploitation of doped magnetic nanoparticle assemblies in biomedicine. © the Owner Societies 2016.

  7. Preparation of Monodisperse Iron Oxide Nanoparticles via the Synthesis and Decomposition of Iron Fatty Acid Complexes

    Directory of Open Access Journals (Sweden)

    Lin Chee-Cheng

    2009-01-01

    Full Text Available Abstract Iron fatty acid complexes (IFACs are prepared via the dissolution of porous hematite powder in hot unsaturated fatty acid. The IFACs are then decomposed in five different organic solvents under reflux conditions in the presence of the respective fatty acid. The XRD analysis results indicate that the resulting NPs comprise a mixture of wustite, magnetite, and maghemite phases. The solvents with a higher boiling point prompt the formation of larger NPs containing wustite as the major component, while those with a lower boiling point produce smaller NPs with maghemite as the major component. In addition, it is shown that unstable NPs with a mixed wustite–magnetite composition can be oxidized to pure maghemite by extending the reaction time or using an oxidizing agent.

  8. Biobased green method to synthesise palladium and iron nanoparticles using Terminalia chebula aqueous extract

    Science.gov (United States)

    Mohan Kumar, Kesarla; Mandal, Badal Kumar; Siva Kumar, Koppala; Sreedhara Reddy, Pamanji; Sreedhar, Bojja

    2013-02-01

    There are many methods to synthesise metal and metal oxide nanoparticles (NPs) using different reducing agents which are hazardous in nature. Although some researchers have used biobased materials for synthesis of these NPs, further research is needed in this area. To explore the scope of bio-extract for the synthesis of transition metal NPs, the present paper synthesises metal NPs replacing hazardous traditional reducing agents. This paper reports the synthesis of palladium and iron NPs, using aqueous extract of Terminalia chebula fruit. Reduction potential of aqueous extract of polyphenolic rich T. chebula was 0.63 V vs. SCE by cyclic voltammetry study which makes it a good green reducing agent. This helps to reduce palladium and iron salts to palladium and iron NPs respectively. Powder X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM) analyses revealed that amorphous iron NPs were within the size less than 80 nm and cubic palladium NPs were within the size less than 100 nm. The synthesised nanomaterials were remarkably stable for a long period and synthesis of stable metal NPs will need to be explored using biobased materials as reducing agents.

  9. Effects of iron-oxide nanoparticles and magnetic fields on oral biofilms

    Science.gov (United States)

    Alas, Gema; Pagano, Ronald E.; Nguyen, Jane Q.; Bandara, H. M. H. Nihal; Ivanov, Sergei A.; Smolyakov, Gennady A.; Huber, Dale L.; Smyth, Hugh D. C.; Osiński, Marek

    2017-02-01

    Human mouth is a host of a large gamut of bacteria species, with over 700 of different bacteria strains identified. Most of these bacterial species are harmless, some are beneficial (such as probiotics assisting in food digestion), but some are responsible for various diseases, primarily tooth decay and gum diseases such as gingivitis and periodontitis. For example, Streptococus mutans produces enamel-eroding acids, while Porphyromonas gingivalis is strongly linked to periodontitis. In this paper, we report on the effects of exposure of oral biofilms to iron oxide nanoparticles and static magnetic fields as possible bactericidal agent.

  10. Coating Optimization of Superparamagnetic Iron Oxide Nanoparticles for High T2 relaxivity

    OpenAIRE

    Tong, Sheng; Hou, Sijian; Zheng, Zhilan; Zhou, Jun; Bao, Gang

    2010-01-01

    We describe a new method for coating superparamagnetic iron oxide nanoparticles (SPIOs) and demonstrate that, by fine-tuning the core size and PEG coating of SPIOs, the T2 relaxivity per-particle can be increased by > 200 fold. With 14 nm core and PEG1000 coating, SPIOs can have T2 relaxivity of 385 s−1mM−1, which is among the highest of all SPIOs reported. In vivo tumor imaging results demonstrated the potential of the SPIOs for clinical applications.

  11. Iron oxide nanoparticle coating of organic polymer-based monolithic columns for phosphopeptide enrichment

    Czech Academy of Sciences Publication Activity Database

    Křenková, Jana; Foret, František

    2011-01-01

    Roč. 34, 16-17 (2011), s. 2106-2112 ISSN 1615-9306 R&D Projects: GA ČR(CZ) GAP301/11/2055; GA ČR(CZ) GPP206/11/P004 Grant - others:Jihomoravský kraj(CZ) 2SGA2721 Program:2SGA Institutional research plan: CEZ:AV0Z40310501 Keywords : iron oxide nanoparticles * monolithic column * phosphopeptide enrichment Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.733, year: 2011

  12. Poly(L-lysine)-modified iron oxide nanoparticles for stem cell labeling

    Czech Academy of Sciences Publication Activity Database

    Babič, Michal; Horák, Daniel; Trchová, Miroslava; Jendelová, Pavla; Růžičková, Kateřina; Lesný, Petr; Herynek, V.; Hájek, M.; Syková, Eva

    2008-01-01

    Roč. 19, č. 3 (2008), s. 740-750 ISSN 1043-1802 R&D Projects: GA AV ČR KAN200200651; GA AV ČR KAN201110651; GA ČR GA203/05/2256; GA ČR(CZ) GA309/06/1594; GA MŠk 1M0538 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z50390703 Keywords : iron oxide * magnetic * nanoparticles Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.584, year: 2008

  13. Colloidally stable surface-modified iron oxide nanoparticles: preparation, characterization and anti-tumor activity

    Czech Academy of Sciences Publication Activity Database

    Macková, Hana; Horák, Daniel; Donchenko, G. V.; Andriyaka, V. I.; Palyvoda, O. M.; Chernishov, V. I.; Chekhun, V. F.; Todor, I. N.; Kuzmenko, O. I.

    2015-01-01

    Roč. 380, 15 April (2015), s. 125-131 ISSN 0304-8853. [International Conference on the Scientific and Clinical Applications of Magnetic Carriers /10./. Dresden, 10.06.2014-14.06.2014] R&D Projects: GA MŠk 7E12054; GA MŠk(CZ) LH14318; GA MŠk(CZ) ED1.1.00/02.0109 EU Projects: European Commission(XE) 259796 - DIATOOLS Institutional support: RVO:61389013 Keywords : iron oxide nanoparticle * poly(N,N-dimethylacrylamide-co-acrylic acid) * protein oxidation Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.357, year: 2015

  14. Photo-fluorescent and magnetic properties of iron oxide nanoparticles for biomedical applications.

    Science.gov (United States)

    Shi, Donglu; Sadat, M E; Dunn, Andrew W; Mast, David B

    2015-05-14

    Iron oxide exhibits fascinating physical properties especially in the nanometer range, not only from the standpoint of basic science, but also for a variety of engineering, particularly biomedical applications. For instance, Fe3O4 behaves as superparamagnetic as the particle size is reduced to a few nanometers in the single-domain region depending on the type of the material. The superparamagnetism is an important property for biomedical applications such as magnetic hyperthermia therapy of cancer. In this review article, we report on some of the most recent experimental and theoretical studies on magnetic heating mechanisms under an alternating (AC) magnetic field. The heating mechanisms are interpreted based on Néel and Brownian relaxations, and hysteresis loss. We also report on the recently discovered photoluminescence of Fe3O4 and explain the emission mechanisms in terms of the electronic band structures. Both optical and magnetic properties are correlated to the materials parameters of particle size, distribution, and physical confinement. By adjusting these parameters, both optical and magnetic properties are optimized. An important motivation to study iron oxide is due to its high potential in biomedical applications. Iron oxide nanoparticles can be used for MRI/optical multimodal imaging as well as the therapeutic mediator in cancer treatment. Both magnetic hyperthermia and photothermal effect has been utilized to kill cancer cells and inhibit tumor growth. Once the iron oxide nanoparticles are up taken by the tumor with sufficient concentration, greater localization provides enhanced effects over disseminated delivery while simultaneously requiring less therapeutic mass to elicit an equal response. Multi-modality provides highly beneficial co-localization. For magnetite (Fe3O4) nanoparticles the co-localization of diagnostics and therapeutics is achieved through magnetic based imaging and local hyperthermia generation through magnetic field or photon

  15. A sonochemical approach to the direct surface functionalization of superparamagnetic iron oxide nanoparticles with (3-aminopropyltriethoxysilane

    Directory of Open Access Journals (Sweden)

    Bashiru Kayode Sodipo

    2014-09-01

    Full Text Available We report a sonochemical method of functionalizing superparamagnetic iron oxide nanoparticles (SPION with (3-aminopropyltriethoxysilane (APTES. Mechanical stirring, localized hot spots and other unique conditions generated by an acoustic cavitation (sonochemical process were found to induce a rapid silanization reaction between SPION and APTES. FTIR, XPS and XRD measurements were used to demonstrate the grafting of APTES on SPION. Compared to what was reported in literature, the results showed that the silanization reaction time was greatly minimized. More importantly, the product displayed superparamagnetic behaviour at room temperature with a more than 20% higher saturation magnetization.

  16. Magnetic removal of Entamoeba cysts from water using chitosan oligosaccharide-coated iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Shukla S

    2015-07-01

    Full Text Available Sudeep Shukla,1 Vikas Arora,2 Alka Jadaun,3 Jitender Kumar,1 Nishant Singh,1 Vinod Kumar Jain1 1School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, Delhi, India; 2Department of Chemistry, Indian Institute of Technology, New Delhi, Delhi, India; 3School of Biotechnology, Jawaharlal Nehru University, New Delhi, Delhi, India Abstract: Amebiasis, a major health problem in developing countries, is the second most common cause of death due to parasitic infection. Amebiasis is usually transmitted by the ingestion of Entamoeba histolytica cysts through oral–fecal route. Herein, we report on the use of chitosan oligosaccharide-functionalized iron oxide nanoparticles for efficient capture and removal of pathogenic protozoan cysts under the influence of an external magnetic field. These nanoparticles were synthesized through a chemical synthesis process. The synthesized particles were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and zeta potential analysis. The particles were found to be well dispersed and uniform in size. The capture and removal of pathogenic cysts were demonstrated by fluorescent microscopy, transmission electron microscopy, and scanning electron microscopy (SEM. Three-dimensional modeling of various biochemical components of cyst walls, and thereafter, flexible docking studies demonstrate the probable interaction mechanism of nanoparticles with various components of E. histolytica cyst walls. Results of the present study suggest that E. histolytica cysts can be efficiently captured and removed from contaminated aqueous systems through the application of synthesized nanoparticles. Keywords: amebiasis, water treatment, nanotechnology

  17. New developments in breast cancer therapy: role of iron oxide nanoparticles

    Science.gov (United States)

    Thoidingjam, Shivani; Bhan Tiku, Ashu

    2017-06-01

    Breast cancer is one of the leading causes of deaths in females worldwide. The high metastatic rate and drug resistance makes it one of the difficult cancers to treat. Early diagnosis and treatment are keys to better survival of breast cancer patients. Conventional treatment approaches like chemotherapy, radiotherapy and surgery suffer from major drawbacks. Novel approaches to improve cancer therapy with minimal damage to normal tissues and better quality of life for cancer patients need to be developed. Among various approaches used for treatment and diagnosis of breast cancer, use of nanoparticles (NPs) is coming up as a new and promising treatment regime. It can help overcome various limitations of conventional therapies like non-targeted effects, resistance to treatment, late diagnosis, etc. Among various nanoparticles studied for their biomedical applications, especially for breast cancer therapy, iron oxide nanoparticles (IONPs) are perhaps the most exciting due to their biocompatibility, biodegradability, size and properties like superparamagnetism. Besides, IONPs are also the only metal oxide nanoparticles approved for clinical use in magnetic resonance imaging (MRI) which is an added advantage for early detection. Therefore in this mini review, we are discussing the developments made in the use of IONPs for breast cancer therapy over the short span of the last five years i.e. 2010-2015. Since late diagnosis and therapy resistance are important drawbacks in breast cancer therapy, the potential of IONPs to overcome these limitations are also evaluated.

  18. Synthesis and characterization of black, red and yellow nanoparticles pigments from the iron sand

    International Nuclear Information System (INIS)

    Mufti, Nandang; Atma, T.; Fuad, A.; Sutadji, E.

    2014-01-01

    The aim of this research is to synthesize nanoparticles of black pigment of Magnetite (Fe 3 O 4 ), red pigment of hematite (α-Fe 2 O 3 ), and yellow pigment of ghoetite (α-FeOOH) from the iron sand. The black pigment of Fe 3 O 4 and the yellow pigment α-FeOOH nanoparticles were synthesized by coprecipitation method with variation of pH. Whereas, the red pigment Fe 2 O 3 was synthesized by sintering Fe 3 O 4 nanoparticles at temperature between 400 °C and 700 7°C for 1 hour. All the pigments has been characterized using X-ray diffraction and SEM. The XRD results shown that the particle size of the black pigmen Fe 3 O 4 , red pigment Fe 3 O 4 and yellow pigment α-FeOOH are around 12, 32, and 30 nm respectively. The particle size of Fe 2 O 3 nanoparticles increase by increasing sintering temperature from 32 nm at 400 °C to 39 nm at 700 °C. For yellow pigment of α-FeOOH, the particle size increase by increasing pH from 30,54 nm at pH 4 to 48,60 nm at pH 7. The SEM results shown that the morphologies of black, yellow and red pigments are aglomarated

  19. Magnetic removal of Entamoeba cysts from water using chitosan oligosaccharide-coated iron oxide nanoparticles.

    Science.gov (United States)

    Shukla, Sudeep; Arora, Vikas; Jadaun, Alka; Kumar, Jitender; Singh, Nishant; Jain, Vinod Kumar

    2015-01-01

    Amebiasis, a major health problem in developing countries, is the second most common cause of death due to parasitic infection. Amebiasis is usually transmitted by the ingestion of Entamoeba histolytica cysts through oral-fecal route. Herein, we report on the use of chitosan oligosaccharide-functionalized iron oxide nanoparticles for efficient capture and removal of pathogenic protozoan cysts under the influence of an external magnetic field. These nanoparticles were synthesized through a chemical synthesis process. The synthesized particles were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and zeta potential analysis. The particles were found to be well dispersed and uniform in size. The capture and removal of pathogenic cysts were demonstrated by fluorescent microscopy, transmission electron microscopy, and scanning electron microscopy (SEM). Three-dimensional modeling of various biochemical components of cyst walls, and thereafter, flexible docking studies demonstrate the probable interaction mechanism of nanoparticles with various components of E. histolytica cyst walls. Results of the present study suggest that E. histolytica cysts can be efficiently captured and removed from contaminated aqueous systems through the application of synthesized nanoparticles.

  20. Removal of Cd (II in Water Samples Using Modified Magnetic Iron Oxide Nanoparticle

    Directory of Open Access Journals (Sweden)

    Ahmad Kakaei

    2015-11-01

    Full Text Available Background: Heavy metals, even at low concentrations, are harmful to human health and environment. Cadmium as a heavy metal is highly toxic and can cause serious threat to living organisms. This research was designed to evaluate the adsorption potential of modified magnetic iron nanoparticles by 2-(5-bromo-2-pyridylazo-5-diethylaminophenol ligand for the removal of cadmium ions from water solutions. Methods: This study was conducted in Ilam Branch, Islamic Azad University, Iran, in 2014. Modified magnetic iron nanoparticle was used as adsorbent for the removal of cadmium from aqueous solution. In batch extraction, the effects of parameters like pH of sample solution (3.0-11.0, initial metal concentrations (50-300 mgL-1, contact time (1.0-10 min and adsorbent dose (10.0-60.0 mg were studied on the adsorption process. Modified magnetite nanoparticle was presented as the adsorbent for the removal of cadmium ions from aqueous samples and later was confirmed by flame atomic absorption spectrometry. Results: The adsorption of cadmium ions on modified magnetite nanoparticles strongly depends on pH. The experimental isothermal data were analyzed using the Langmuir and Freundlich equations. The removal process followed the Langmuir isotherm. Maximum adsorption capacity for the adsorption of cadmium ions by the sorbent was 24.09 mgg-1. Conclusion: The method was successfully applied to adsorption of cadmium in water samples with satisfactory results. Other advantages include high capacity, good stability and fast adsorption kinetics. High pre-concentration factor was obtained easily by this method (120 and low analysis cost.

  1. Effect of Stabilized Zero-Valent Iron Nanoparticles on Nitrate Removal from Sandy Soil

    Directory of Open Access Journals (Sweden)

    F. Nooralivand

    2016-02-01

    Full Text Available Introduction: During the recent decades, the use of N fertilizers has undeniable development regardless of their effects on the soil and environment. Increasing nitrate ion concentration in soil solution and then, leaching it into groundwater causes increase nitrate concentration in the water and raise the risk suffering from the people to some diseases. World health organization recommended maximum concentration level for nitrate and nitrite in the drinking water 50 and 3 mg/l, respectively. There are different technologies for the removal of nitrate ions from aqueous solution. The conventional methods are ion exchange, biological denitrification, reverse osmosis and chemical reduction. Using nanoscale Fe0 particles compared to other methods of nitrate omission was preferred because of; its high surface area, more reactive, lower cost and higher efficiency. More studies on the reduction of nitrate by zero-valent iron nanoparticles have been in aqueous solutions or in the soil in batch scale. Nanoparticles surface modified with poly-electrolytes, surfactants and polymers cause colloidal stability of the particles against the forces of attraction between particles and increases nanoparticle transport in porous media. The objectives of this study were to synthesize carboxymethyl cellulose stabilized zero-valent iron nanoparticles and consideration of their application for nitrate removal from sandy soil. Materials and Methods: The nanoparticles were synthesized in a lab using borohydride reduction method and their morphological characteristics were examined via scanning electron microscopy (SEM, X-ray diffraction (XRD and Fourier Transmission Infrared Spectroscopy (FTIR. Experiments were conducted on packed sand column (40 cm length and 2.5 cm inner diameter under conditions of different nanoparticle concentration (1, 2, and 3 g1-1and high initial NO3- concentration (150, 250, and 350 mgl-1. Homogeneous soil column was filled with the wet packed

  2. Polarization-dependent transverse-stress sensing based on photonic crystal fiber with gold-coated air-holes

    Science.gov (United States)

    Liu, Hai; Zhu, Chenghao; Wang, Yan; Tan, Ce; Li, Hongwei; Cheng, Deqiang

    2017-05-01

    A transverse-stress sensor with polarization filtering function based on a specially designed photonic crystal fiber (PCF) is proposed. Four ultralarge side-holes are introduced into the cladding layer, and two of them are gold-coated to enhance the stress sensitivity. The finite element method is applied to study the polarization-dependent wavelength-selective sensing characteristics at the optical communication wavelength. Results reveal that the sensor can achieve a high sensitivity in either direction that can be divided into an x-direction component and a y-direction component. Combining the advantages of side-hole structure and surface plasmon resonance technology, the proposed sensor is believed to be an excellent candidate for the transverse-stress measurement.

  3. Synthesis and Application of Amine Functionalized Iron Oxide Nanoparticles on Menaquinone-7 Fermentation: A Step towards Process Intensification

    OpenAIRE

    Ebrahiminezhad, Alireza; Varma, Vikas; Yang, Shuyi; Ghasemi, Younes; Berenjian, Aydin

    2015-01-01

    Industrial production of menaquione-7 by Bacillus subtilis natto is associated with major drawbacks. To address the current challenges in menaquione-7 fermentation, studying the effect of magnetic nanoparticles on the bacterial cells can open up a new domain for intensified menqainone-7 process. This article introduces the new concept of production and application of l-lysine coated iron oxide nanoparticles (l-Lys@IONs) as a novel tool for menaquinone-7 biosynthesis. l-Lys@IONs with the avera...

  4. Green synthesis of iron nanoparticles and their application as a Fenton-like catalyst for the degradation of aqueous cationic and anionic dyes

    OpenAIRE

    Shahwan, Talal; Abu-Sirriah, Sadieh; Nairat, Muath; Boyacı, Ezel; Eroğlu, Ahmet E.; Scott, Thomas B.; Hallam, Keith R.

    2011-01-01

    Iron nanoparticles were produced using extracts of green tea leaves (GT-Fe NPs). The materials were characterized using TEM, SEM/EDX, XPS, XRD, and FTIR techniques and were shown to contain mainly iron oxide and iron oxohydroxide. The obtained nanoparticles were then utilized as a Fenton-like catalyst for decolorization of aqueous solutions containing methylene blue (MB) and methyl orange (MO) dyes. The related experiments investigated the removal kinetics and the effect of concentration for ...

  5. A detailed study on the transition from the blocked to the superparamagnetic state of reduction-precipitated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Witte, K.; Bodnar, W. [University of Rostock, Institute of Physics, August – Bebel – Str. 55, D-18055 Rostock (Germany); Mix, T. [IFW Dresden, Institute for Metallic Materials, PO Box 270116, D-01171 Dresden (Germany); Schell, N. [Helmholtz-Center Geesthacht, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht (Germany); Fulda, G. [University Medicine Rostock, Medical Biology and Electron Microscopy Centre, Strempelstr. 14, D-18057 Rostock (Germany); Woodcock, T.G. [IFW Dresden, Institute for Metallic Materials, PO Box 270116, D-01171 Dresden (Germany); Burkel, E. [University of Rostock, Institute of Physics, August – Bebel – Str. 55, D-18055 Rostock (Germany)

    2016-04-01

    Magnetic iron oxide nanoparticles were prepared by salt-assisted solid-state chemical precipitation method with alternating fractions of the ferric iron content. The physical properties of the precipitated nanoparticles mainly consisting of magnetite were investigated by means of transmission electron microscopy, high energy X-ray diffraction, vibrating sample magnetometry and Mössbauer spectroscopy. With particle sizes ranging from 16.3 nm to 2.1 nm, a gradual transition from the blocked state to the superparamagnetic state was observed. The transition was described as a dependence of the ferric iron content used during the precipitation. Composition, mean particle size, coercivity, saturation polarisation, as well as hyperfine interaction parameters and their evolution were studied systematically over the whole series of iron oxide nanoparticles. - Highlights: • Study of superparamagnetic transition of magnetite varying ferric iron content. • Coercivity is mainly influenced by the particle size. • Saturation polarisation influenced by the goethite content and the particle size. • Number of vacancies tend to increase with increasing ferric iron content. • Fe{sub 3}O{sub 4} B-sites are stronger effected by the reduction of particle size than A-sites.

  6. Synthesis of Iron Nanoparticles using Extracts of Native Fruits of Ecuador, as Capuli (Prunus serotina) and Mortiño (Vaccinium floribundum)

    OpenAIRE

    Arroyo Rodríguez, Carlos

    2016-01-01

    This study describes an eco-friendly synthesis for the production of zero-valent iron nanoparticles (nZVIs). Extracts of capulí (Prunus serotina) and mortiño (Vaccinium floribundum) were used as reducing and stabilizer agents. Freshly prepared nanoparticles were characterized with Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectrometry (FTIR). Zerovalent iron nanoparticles with mortiño extract (V. ...

  7. Biosynthesized iron nanoparticles in aqueous extracts of Eichhornia crassipes and its mechanism in the hexavalent chromium removal

    Science.gov (United States)

    Wei, Yufen; Fang, Zhanqiang; Zheng, Liuchun; Tsang, Eric Pokeung

    2017-03-01

    Eichhornia crassipes (water hyacinth), a species of invasive weeds has caused serious ecological damage due to its extraordinary fertility and growth rate. However, it has not yet been exploited for use as a resource. This paper reported the synthesis and characterization of amorphous iron nanoparticles (Ec-Fe-NPs) from Fe(III) salts in aqueous extracts of Eichhornia crassipes. The nanoparticles were characterized by SEM, EDS, TEM, XPS, FTIR, DLS and the zeta potential methods. The characterization results confirmed the successful synthesis of amorphous iron nanoparticles with diameters of 20-80 nm. Moreover, the nanoparticles were mainly composed of zero valent iron nanoparticles which were coated with various organic matters in the extracts as a capping or stabilizing agents. Batch experiments showed that 89.9% of Cr(VI) was removed by the Ec-Fe-NPs much higher than by the extracts alone (20.4%) and Fe3O4 nanoparticles (47.3%). Based on the kinetics study and the XPS analysis, a removal mechanism dominated by adsorption and reduction with subsequently co-precipitation was proposed.

  8. Enhanced magnetic resonance contrast of iron oxide nanoparticles embedded in a porous silicon nanoparticle host

    Science.gov (United States)

    Kinsella, Joseph; Ananda, Shalini; Andrew, Jennifer; Grondek, Joel; Chien, Miao-Ping; Scandeng, Miriam; Gianneschi, Nathan; Ruoslahti, Erkki; Sailor, Michael

    2013-02-01

    In this report, we prepared a porous Si nanoparticle with a pore morphology that facilitates the proximal loading and alignment of magnetite nanoparticles. We characterized the composite materials using superconducting quantum interference device magnetometry, dynamic light scattering, transmission electron microscopy, and MRI. The in vitro cytotoxicity of the composite materials was tested using cell viability assays on human liver cancer cells and rat hepatocytes. An in vivo analysis using a hepatocellular carcinoma (HCC) Sprague Dawley rat model was used to determine the biodistribution properties of the material, while naïve Sprague Dawley rats were used to determine the pharmocokinetic properties of the nanomaterials. The composite material reported here demonstrates an injectable nanomaterial that exploits the dipolar coupling of superparamagnetic nanoparticles trapped within a secondary inorganic matrix to yield significantly enhanced MRI contrast. This preparation successfully avoids agglomeration issues that plague larger ferromagnetic systems. A Fe3O4:pSi composite formulation consisting of 25% by mass Fe3O4 yields an maximal T2* value of 556 mM Fe-1 s-1. No cellular (HepG2 or rat hepatocyte cells) or in vivo (rat) toxicity was observed with the formulation, which degrades and is eliminated after 4-8 h in vivo. The ability to tailor the magnetic properties of such materials may be useful for in vivo imaging, magnetic hyperthermia, or drug-delivery applications.

  9. Nanoparticle Zere-valent Iron Affect on As (V Removal from Drinking Water

    Directory of Open Access Journals (Sweden)

    Hamed Koohpayehzadeh

    2012-10-01

    Full Text Available Arsenic which is present in the underground and surface water is one of the most toxic elements threating human health and animals. Arsenic has been removed in different type of ways. In this study Arsenic removal from drinking water and its decreasing rates were investigated by NZVI (nanoparticle zerovalent iron to standard limit (I.e.  0.01 mg/lit . The tests were conducted on reactor containing 100 ml water containing 1mg/L. Arsenic by virtue of Batch method. The mixture was executed in mixing was done an Oultrasnic device in order to have better mixture and complete distribution of nanoparticles in water. Then the arsenic was removed from the water by VATMAN paper of 0.45 Hm. The remained arsenic in the water was measured by ICP device. In this article the influence of the parameters including mixture time , PH ,NZVI and arcenic doses were examined . Having perfomed many tests the results showed that 1 mg arsenic can be removed 100 percent by 0.05 g NZVI in 8 min. It is possible to remove by 98 percent arsenic in 5-10 PH range. Iron nanopaticle way is an effective and rapid way to remove arsenic from water and various conditions have not considerable effect on it.

  10. Photoactive nanocomplex formed from chlorophyll assembly on TMA-coated iron oxide nanoparticles

    Science.gov (United States)

    Barbaros, Sibel; Meray, Zeynep; Tecim, Tuğba; Genç, Rükan

    2016-07-01

    In this study, hierarchical self-assembly of photocatalytic nanodisks through non-covalent interactions between spinach-extracted chlorophyll molecules and trimethylammonium hydroxide-coated magnetic iron oxide nanoparticles was discussed. Combination of chlorophyll molecules with iron oxide nanoparticles generated an alteration in light absorption at both visible and near-IR region with accompanying enhancement in fluorescence emission. Further, photocatalytic role of resulting molecular assembly was studied by means of the photoinduced degradation of methylene blue dye under UV light and direct sun irradiation at neutral pH. In order to enhance the long-term stability of the hybrid nanocatalyst, commercially available cellulose membrane was used as a support and magnetic recovery and reusability was achieved where the nanocatalyst retained more than 90 % of its efficiency even after four cycles. This simple strategy could initiate the development of new materials for wastewater treatment including membrane-based technologies. On the other hand, their sunlight-induced photocatalytic activity could easily be conducted to dye-synthesized solar cells or their enhanced photoluminescence can provide a strong basis for future bioimaging tools.

  11. Photoactive nanocomplex formed from chlorophyll assembly on TMA-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Barbaros, Sibel; Meray, Zeynep; Tecim, Tuğba; Genç, Rükan, E-mail: rukangnc@gmail.com [Mersin University, Functional Nanomaterials Laboratory, Chemical Engineering Department, Engineering Faculty (Turkey)

    2016-07-15

    In this study, hierarchical self-assembly of photocatalytic nanodisks through non-covalent interactions between spinach-extracted chlorophyll molecules and trimethylammonium hydroxide-coated magnetic iron oxide nanoparticles was discussed. Combination of chlorophyll molecules with iron oxide nanoparticles generated an alteration in light absorption at both visible and near-IR region with accompanying enhancement in fluorescence emission. Further, photocatalytic role of resulting molecular assembly was studied by means of the photoinduced degradation of methylene blue dye under UV light and direct sun irradiation at neutral pH. In order to enhance the long-term stability of the hybrid nanocatalyst, commercially available cellulose membrane was used as a support and magnetic recovery and reusability was achieved where the nanocatalyst retained more than 90 % of its efficiency even after four cycles. This simple strategy could initiate the development of new materials for wastewater treatment including membrane-based technologies. On the other hand, their sunlight-induced photocatalytic activity could easily be conducted to dye-synthesized solar cells or their enhanced photoluminescence can provide a strong basis for future bioimaging tools.Graphical Abstract.

  12. Synthesis and characterization of superparamagnetic iron oxide nanoparticles as calcium-responsive MRI contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Pengfei [State Key Laboratory Breeding Base of Nonferrous Metals and Specific Materials Processing, School of Materials Science and Engineering, Guilin University of Technology, Jian Gan Road 12, Guilin 541004 (China); Shen, Zhiwei [Second Affiliated Hospital of Shantou University Medical College, Dong Xia North Road, Shantou 515041,China (China); Zhang, Baolin, E-mail: baolinzhang@ymail.com [State Key Laboratory Breeding Base of Nonferrous Metals and Specific Materials Processing, School of Materials Science and Engineering, Guilin University of Technology, Jian Gan Road 12, Guilin 541004 (China); Wang, Jun [State Key Laboratory Breeding Base of Nonferrous Metals and Specific Materials Processing, School of Materials Science and Engineering, Guilin University of Technology, Jian Gan Road 12, Guilin 541004 (China); Wu, Renhua, E-mail: rhwu@stu.edu.cn [Second Affiliated Hospital of Shantou University Medical College, Dong Xia North Road, Shantou 515041,China (China)

    2016-12-15

    Highlights: • SPIONs were conjugated with EGTA by EDC/sulfo-NHS method. • The presence of Ca{sup 2+} induced the aggregation of EGTA-SPIONs. • The aggregation of EGTA-SPIONs increased the T2 relaxation time. • EGTA-SPIONs can be used for the calcium imaging with MRI. - Abstract: Superparamagnetic iron oxide nanoparticles (SPIONs) as T2 contrast agents have great potential to sense calcium ion (Ca{sup 2+}) using magnetic resonance imaging (MRI). Here we prepared calcium-responsive SPIONs for MRI, formed by combining poly(ethylene glycol) (PEG) and polyethylenimine (PEI) coated iron oxide nanoparticle (PEI/PEG-SPIONs) contrast agents with the straightforward calcium-sensing compound EGTA (ethylene glycol tetraacetic acid). EGTA was conjugated onto PEI/PEG-SPIONs using EDC/sulfo-NHS method. EGTA-SPIONs were characterized using TEM, XPS, DSL, TGA and SQUIID. DSL results show that the SPIONs aggregate in the presence of Ca{sup 2+}. MRI analyses indicate that the water proton T2 relaxation rates in HEPES suspensions of the EGTA-SPIONs significantly increase with the calcium concentration because the SPIONs aggregate in the presence of Ca{sup 2+}. The T2 values decreased 25% when Ca{sup 2+} concentration decreased from 1.2 to 0.8 mM. The aggregation of EGTA-SPIONs could be reversed by EDTA. EGTA-SPIONs have potential as smart contrast agents for Ca{sup 2+}-sensitive MRI.

  13. Fabrication and Application of Iron(III-Oxide Nanoparticle/Polydimethylsiloxane Composite Cone in Microfluidic Channels

    Directory of Open Access Journals (Sweden)

    Cheng-Chun Huang

    2012-01-01

    Full Text Available This paper presented the fabrication and applications of an iron(III-oxide nanoparticle/polydimethylsiloxane (PDMS cone as a component integrated in lab on a chip. The two main functions of this component were to capture magnetic microbeads in the microfluid and to mix two laminar fluids by generating disturbance. The iron(III-oxide nanoparticle/PDMS cone was fabricated by automatic dispensing and magnetic shaping. Three consecutive cones of 300 μm in height were asymmetrically placed along a microchannel of 2 mm in width and 1.1 mm in height. Flow passing the cones was effectively redistributed for Renolds number lower than . Streptavidin-coated magnetic microbeads which were bound with biotin were successfully captured by the composite cones as inspected under fluorescence microscope. The process parameters for fabricating the composite cones were investigated. The fabricated cone in the microchannel could be applied in lab on a chip for bioassay in the future.

  14. Iron-dependent formation of reactive oxygen species and glutathione depletion after accumulation of magnetic iron oxide nanoparticles by oligodendroglial cells

    International Nuclear Information System (INIS)

    Hohnholt, Michaela C.; Dringen, Ralf

    2011-01-01

    Magnetic iron oxide nanoparticles (IONP) are currently used for various neurobiological applications. To investigate the consequences of a treatment of brain cells with such particles, we have applied dimercaptosuccinate (DMSA)-coated IONP that had an average hydrodynamic diameter of 60 nm to oligodendroglial OLN-93 cells. After exposure to 4 mM iron applied as DMSA–IONP, these cells increased their total specific iron content within 8 h 600-fold from 7 to 4,200 nmol/mg cellular protein. The strong iron accumulation was accompanied by a change in cell morphology, although the cell viability was not compromized. DMSA–IONP treatment caused a concentration-dependent increase in the iron-dependent formation of reactive oxygen species and a decrease in the specific content of the cellular antioxidative tripeptide glutathione. During a 16 h recovery phase in IONP-free culture medium following exposure to DMSA–IONP, OLN-93 cells maintained their high iron content and replenished their cellular glutathione content. These data demonstrate that viable OLN-93 cells have a remarkable potential to deal successfully with the consequences of an accumulation of large amounts of iron after exposure to DMSA–IONP.

  15. Thermally induced phase transformation in multi-phase iron oxide nanoparticles on vacuum annealing

    Science.gov (United States)

    Anupama, A. V.; Keune, W.; Sahoo, B.

    2017-10-01

    The evolution of magnetic phases in multi-phase iron oxide nanoparticles, synthesized via the transferred arc plasma induced gas phase condensation method, was investigated by X-ray diffraction, vibrating sample magnetometry and 57Fe Mössbauer spectroscopy. The particles are proposed to be consisting of three different iron oxide phases: α-Fe2O3, γ-Fe2O3 and Fe3O4. These nanoparticles were exposed to high temperature (∼935 K) under vacuum (10-3 mbar He pressure), and the thermally induced phase transformations were investigated. The Rietveld refinement of the X-ray diffraction data corroborates the least-squares fitting of the transmission Mössbauer spectra in confirming the presence of Fe3O4, γ-Fe2O3 and α-Fe2O3 phases before the thermal treatment, while only Fe3O4 and α-Fe2O3 phases exist after thermal treatment. On thermal annealing in vacuum, conversion from γ-Fe2O3 to Fe3O4 and α-Fe2O3 was observed. Interestingly, we have observed a phase transformation occurring in the temperature range ∼498 K-538 K, which is strikingly lower than the phase transformation temperature of γ-Fe2O3 to α-Fe2O3 (573-623 K) in air. Combining the results of Rietveld refinement of X-ray diffraction patterns and Mössbauer spectroscopy, we have attributed this phase transformation to the phase conversion of a metastable "defected and strained" d-Fe3O4 phase, present in the as-prepared sample, to the α-Fe2O3 phase. Stabilization of the phases by controlling the phase transformations during the use of different iron-oxide nanoparticles is the key factor to select them for a particular application. Our investigation provides insight into the effect of temperature and chemical nature of the environment, which are the primary factors governing the phase stability, suitability and longevity of the iron oxide nanomaterials prepared by the gas-phase condensation method for various applications.

  16. Comparing different commercial zero valent iron nanoparticles to immobilize As and Hg in brownfield soil.

    Science.gov (United States)

    Gil-Díaz, M; Alonso, J; Rodríguez-Valdés, E; Gallego, J R; Lobo, M C

    2017-04-15

    Nanoscale zero valent iron (nZVI) particles obtained by different methods differ in their structure, which lead to different reactivity, and therefore a likely difference in the remediation efficiency. The present study compares the effectiveness of three commercial ZVI nanoparticles to immobilize As and Hg in two soils (A and B) collected from a brownfield highly contaminated by mining and metallurgy activities. Scarce data are available on the effectiveness of nZVI for Hg immobilization in soil. Two commercial nZVI slurries from Toda (RNIP and RNIP-D) and one from Nano Iron (25S) were used at different doses (1, 5 and 10%). The metal(loid) availability and mobility was evaluated with the TCLP test and Tessier extraction procedure. The influence of nZVI application on As and Hg speciation was also evaluated as well as its impact on soil pH, electrical conductivity and soil phytotoxicity to vetch germination. The three commercial nZVI particles significantly reduced As and Hg availability in the two soils studied, which led to a decrease in soil phytotoxicity. At the dose of 5% of nZVI a decrease of exchangeable-As higher than 70% was observed for both soils, whereas in the case of Hg, a higher dose of nZVI (10%) was necessary to achieve reductions of exchangeable-Hg between 63 and 90% depending on the type of nZVI and soil. No impact on soil pH and electrical conductivity was observed. The effectiveness of metal(loid) immobilization depended on type of nZVI, soil properties and metal(loid) characteristics. Nanoparticles from Nano Iron showed better results for As immobilization whereas RNIP nanoparticles were more effective for Hg. Overall, 25S at the dose of 5% resulted more effective than RNIP nanoparticles for the reduction of exchangeable-As (in the range of 6-14%), whereas RNIP and RNIP-D were 10 and 13% more effective, respectively, for the reduction of exchangeable-Hg at the dose of 10% in soil B. Thus, nZVI can be used for the remediation of highly As and

  17. Direct synthesis of magnetite nanoparticles from iron(II) carboxymethylcellulose and their performance as NMR contrast agents

    Science.gov (United States)

    da Silva, Delmarcio Gomes; Hiroshi Toma, Sergio; de Melo, Fernando Menegatti; Carvalho, Larissa Vieira C.; Magalhães, Alvicler; Sabadini, Edvaldo; dos Santos, Antônio Domingues; Araki, Koiti; Toma, e. Henrique E.

    2016-01-01

    Iron(II) carboxymethylcellulose (CMC) has been successfully employed in the synthesis of hydrophylic magnetite nanoparticles stabilized with a biopolymer coating, aiming applications in NMR imaging. The new method encompasses a convenient one-step synthetic procedure, allowing a good size control and yielding particles of about 10 nm (core size). In addition to the biocompatibility, the nanoparticles have promoted a drastic reduction in the transverse relaxation time (T2) of the water protons. The relaxivity rates have been investigated as a function of the nanoparticles concentration, showing a better performance in relation to the common NMR contrast agents available in the market.

  18. Generation of oxidant response to copper and iron nanoparticles and salts: Stimulation by ascorbate.

    Science.gov (United States)

    Rice, Robert H; Vidrio, Edgar A; Kumfer, Benjamin M; Qin, Qin; Willits, Neil H; Kennedy, Ian M; Anastasio, Cort

    2009-10-30

    The present work describes a two-stage approach to analyzing combustion-generated samples for their potential to produce oxidant stress. This approach is illustrated with the two commonly encountered transition metals, copper and iron. First, their abilities to generate hydroxyl radical were measured in a cell-free, phosphate-buffered saline solution containing ascorbate and/or citrate. Second, their abilities to induce heme oxygenase-1 in cultured human epidermal keratinocytes were assessed in cell culture. Combustion-generated copper oxide nanoparticles were active in both assays and were found to be soluble in culture medium. Depletion of glutathione in the cells or loading the cells with ascorbate greatly increased heme oxygenase-1 induction in the presence of copper. By contrast, iron oxide nanoparticles were active in the phosphate-buffered saline but not in cell culture, and they aggregated in culture medium. Soluble salts of copper and iron exhibited the same contrast in activities as the respective combustion-generated particles. The results suggest that the capability of combustion-generated environmental samples to produce oxidant stress can be screened effectively in a two step process, first in phosphate-buffered saline with ascorbate and subsequently in epithelial cell culture for those exhibiting activity initially. The results also point to an unanticipated interaction in cells of oxidant stress-generating metals with an antioxidant (ascorbate) that is usually missing in culture medium formulations. Thus, ascorbate supplementation of cultured human cells is likely to improve their ability to model the in vivo effects of particulate matter containing copper and other redox-active metals.

  19. Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type.

    Science.gov (United States)

    Gomes, Helena I; Dias-Ferreira, Celia; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2015-07-01

    Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two-compartment and the three-compartment cell, respectively. The highest removal with Soil 2 were 58% and 45%, in the two-compartment and the three-compartment cell, respectively, in the experiments without direct current. The pH of the soil suspension in the two-compartment treatment appears to be a determining factor for the PCB dechlorination, and this cell allowed a uniform distribution of the nanoparticles in the soil, while there was iron accumulation in the injection reservoir in the three-compartment cell. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Fabrication of a Functionalized Magnetic Bacterial Nanocellulose with Iron Oxide Nanoparticles.

    Science.gov (United States)

    Arias, Sandra L; Shetty, Akshath R; Senpan, Angana; Echeverry-Rendón, Mónica; Reece, Lisa M; Allain, Jean Paul

    2016-05-26

    In this study, bacterial nanocellulose (BNC) produced by the bacteria Gluconacetobacter xylinus is synthesized and impregnated in situ with iron oxide nanoparticles (IONP) (Fe3O4) to yield a magnetic bacterial nanocellulose (MBNC). The synthesis of MBNC is a precise and specifically designed multi-step process. Briefly, bacterial nanocellulose (BNC) pellicles are formed from preserved G. xylinus strain according to our experimental requirements of size and morphology. A solution of iron(III) chloride hexahydrate (FeCl3·6H2O) and iron(II) chloride tetrahydrate (FeCl2·4H2O) with a 2:1 molar ratio is prepared and diluted in deoxygenated high purity water. A BNC pellicle is then introduced in the vessel with the reactants. This mixture is stirred and heated at 80 °C in a silicon oil bath and ammonium hydroxide (14%) is then added by dropping to precipitate the ferrous ions into the BNC mesh. This last step allows forming in situ magnetite nanoparticles (Fe3O4) inside the bacterial nanocellulose mesh to confer magnetic properties to BNC pellicle. A toxicological assay was used to evaluate the biocompatibility of the BNC-IONP pellicle. Polyethylene glycol (PEG) was used to cover the IONPs in order to improve their biocompatibility. Scanning electron microscopy (SEM) images showed that the IONP were located preferentially in the fibril interlacing spaces of the BNC matrix, but some of them were also found along the BNC ribbons. Magnetic force microscope measurements performed on the MBNC detected the presence magnetic domains with high and weak intensity magnetic field, confirming the magnetic nature of the MBNC pellicle. Young's modulus values obtained in this work are also in a reasonable agreement with those reported for several blood vessels in previous studies.

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

    Science.gov (United States)

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

    2014-01-01

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

  2. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy

    Directory of Open Access Journals (Sweden)

    Yang R

    2016-12-01

    Full Text Available Rui-Meng Yang,1,* Chao-Ping Fu,2,* Jin-Zhi Fang,1 Xiang-Dong Xu,1 Xin-Hua Wei,1 Wen-Jie Tang,1 Xin-Qing Jiang,1 Li-Ming Zhang2 1Department of Radiology, Guangzhou First People’s Hospital, Guangzhou Medical University, 2School of Materials Science and Engineering, School of Chemistry, Sun Yat-sen University, Guangzhou, China *These authors contributed equally to this work Abstract: Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs, which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhancement on T2-weighted magnetic resonance imaging and photothermal effect targeted CD44 HA receptor-overexpressing breast cancer. All these results indicated that HA-SPIONs have great potential for effective diagnosis and treatment of cancer. Keywords: iron oxide nanoparticles, surface functionalization, bioactive glycosaminoglycan, magnetic resonance imaging, cellular uptake, breast carcinoma

  3. A facile method to prepare superparamagnetic iron oxide and hydrophobic drug-encapsulated biodegradable polyurethane nanoparticles

    Directory of Open Access Journals (Sweden)

    Cheng K

    2017-03-01

    Full Text Available Kuo-Wei Cheng, Shan-hui Hsu Institute of Polymer Science and Engineering, College of Engineering, National Taiwan University, Taipei, Taiwan, Republic of China Abstract: Superparamagnetic iron oxide nanoparticles (SPIO NPs have a wide range of biomedical applications such as in magnetic resonance imaging, targeting, and hyperthermia therapy. Aggregation of SPIO NPs can occur because of the hydrophobic surface and high surface energy of SPIO NPs. Here, we developed a facile method to encapsulate SPIO NPs in amphiphilic biodegradable polymer. Anionic biodegradable polyurethane nanoparticles (PU NPs with ~35 nm size and different chemistry were prepared by waterborne processes. SPIO NPs were synthesized by chemical co-precipitation. SPIO NPs were then added to the aqueous dispersion of PU NPs, followed by application of high-frequency (~20 kHz ultrasonic vibration for 3 min. This method rendered SPIO-PU hybrid NPs (size ~110 nm suspended in water. SPIO-PU hybrid NPs contained ~50–60 wt% SPIO and retained the superparamagnetic property (evaluated by a magnetometer as well as high contrast in magnetic resonance imaging. SPIO-PU NPs also showed the ability to provide cell hyperthermic treatment. Using the same ultrasonic method, hydrophobic drug (Vitamin K3 [VK3] or (9-(methylaminomethylanthracene [MAMA] could also be encapsulated in PU NPs. The VK3-PU or MAMA-PU hybrid NPs had ~35 nm size and different release profiles for PUs with different chemistry. The encapsulation efficiency for VK3 and MAMA was high (~95% without burst release. The encapsulation mechanism may be attributed to the low glass transition temperature (Tg and good mechanical compliance of PU NPs. The new encapsulation method involving waterborne biodegradable PU NPs is simple, rapid, and effective to produce multimodular NP carriers. Keywords: superparamagnetic iron oxide, polyurethane, drug release, hybrid nanoparticles

  4. Enlightening mineral iron sensing in Pseudomonas fluorescens by surface active maghemite nanoparticles: Involvement of the OprF porin.

    Science.gov (United States)

    Magro, Massimiliano; Fasolato, Luca; Bonaiuto, Emanuela; Andreani, Nadia Andrea; Baratella, Davide; Corraducci, Vittorino; Miotto, Giovanni; Cardazzo, Barbara; Vianello, Fabio

    2016-10-01

    Mineral iron(III) recognition by bacteria is considered a matter of debate. The peculiar surface chemistry of novel naked magnetic nanoparticles, called SAMNs (surface active maghemite nanoparticles) characterized by solvent exposed Fe(3+) sites on their surface, was exploited for studying mineral iron sensing in Pseudomonas fluorescens. SAMNs were applied for mimicking Fe(3+) ions in solution, acting as magnetically drivable probes to evaluate putative Fe(3+) recognition sites on the microorganism surface. Culture broths and nano-bio-conjugates were characterized by UV-Vis spectroscopy and mass spectrometry. The whole heritage of a membrane porin (OprF) of P. fluorescens Ps_22 cells was recognized and firmly bound by SAMNs. The binding of nanoparticles to OprF porin was correlated to a drastic inhibition of a siderophore (pyoverdine) biosynthesis and to the stimulation of the production and rate of formation of a secondary siderophore. The analysis of metabolic pathways, based on P. fluorescens Ps_22 genomic information, evidenced that this putative secondary siderophore does not belong to a selection of the most common siderophores. In the scenario of an adhesion mechanism, it is plausible to consider OprF as the biological component deputed to the mineral iron sensing in P. fluorescens Ps_22, as well as one key of siderophore regulation. The present work sheds light on mineral iron sensing in microorganisms. Peculiar colloidal naked iron oxide nanoparticles offer a useful approach for probing the adhesion of bacterial surface on mineral iron for the identification of the specific recognition site for this iron uptake regulation in microorganisms. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Magnetically Assembled SERS Substrates Composed of Iron-Silver Nanoparticles Obtained by Laser Ablation in Liquid.

    Science.gov (United States)

    Scaramuzza, Stefano; Badocco, Denis; Pastore, Paolo; Coral, Diego F; Fernández van Raap, Marcela B; Amendola, Vincenzo

    2017-05-05

    The widespread application of surface-enhanced Raman scattering (SERS) would benefit from simple and scalable self-assembly procedures for the realization of plasmonic arrays with a high density of electromagnetic hot-spots. To this aim, the exploitation of iron-doped silver nanoparticles (NPs) synthesized by laser ablation of a bulk bimetallic iron-silver target immersed in ethanol is described. The use of laser ablation in liquid is key to achieving bimetallic NPs in one step with a clean surface available for functionalization with the desired thiolated molecules. These iron-silver NPs show SERS performances, a ready response to external magnetic fields and complete flexibility in surface coating. All these characteristics were used for the magnetic assembly of plasmonic arrays which served as SERS substrates for the identification of molecules of analytical interest. The magnetic assembly of NPs allowed a 28-fold increase in the SERS signal of analytes compared to not-assembled NPs. The versatility of substrate preparation and the SERS performances were investigated as a function of NPs surface coating among different thiolated ligands. These results show a simple procedure to obtain magnetically assembled regenerable plasmonic arrays for repeated SERS investigation of different samples, and it can be of inspiration for the realization of other self-assembled and reconfigurable magnetic-plasmonic devices. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Coating-dependent induction of cytotoxicity and genotoxicity of iron oxide nanoparticles.

    Science.gov (United States)

    Magdolenova, Zuzana; Drlickova, Martina; Henjum, Kristi; Rundén-Pran, Elise; Tulinska, Jana; Bilanicova, Dagmar; Pojana, Giulio; Kazimirova, Alena; Barancokova, Magdalena; Kuricova, Miroslava; Liskova, Aurelia; Staruchova, Marta; Ciampor, Fedor; Vavra, Ivo; Lorenzo, Yolanda; Collins, Andrew; Rinna, Alessandra; Fjellsbø, Lise; Volkovova, Katarina; Marcomini, Antonio; Amiry-Moghaddam, Mahmood; Dusinska, Maria

    2015-05-01

    Surface coatings of nanoparticles (NPs) are known to influence advantageous features of NPs as well as potential toxicity. Iron oxide (Fe3O4) NPs are applied for both medical diagnostics and targeted drug delivery. We investigated the potential cytotoxicity and genotoxicity of uncoated iron oxide (U-Fe3O4) NPs in comparison with oleate-coated iron oxide (OC-Fe3O4) NPs. Testing was performed in vitro in human lymphoblastoid TK6 cells and in primary human blood cells. For cytotoxicity testing, relative growth activity, trypan blue exclusion, (3)H-thymidine incorporation and cytokinesis-block proliferation index were assessed. Genotoxicity was evaluated by the alkaline comet assay for detection of strand breaks and oxidized purines. Particle characterization was performed in the culture medium. Cellular uptake, morphology and pathology were evaluated by electron microscopy. U-Fe3O4 NPs were found not to be cytotoxic (considering interference of NPs with proliferation test) or genotoxic under our experimental conditions. In contrast, OC-Fe3O4 NPs were cytotoxic in a dose-dependent manner, and also induced DNA damage, indicating genotoxic potential. Intrinsic properties of sodium oleate were excluded as a cause of the toxic effect. Electron microscopy data were consistent with the cytotoxicity results. Coating clearly changed the behaviour and cellular uptake of the NPs, inducing pathological morphological changes in the cells.

  7. Effect of surface charge on the colloidal stability and in vitro uptake of carboxymethyl dextran-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ayala, Vanessa; Herrera, Adriana P.; Latorre-Esteves, Magda; Torres-Lugo, Madeline [University of Puerto Rico, Department of Chemical Engineering (United States); Rinaldi, Carlos, E-mail: carlos.rinaldi@bme.ufl.edu [University of Florida, J. Crayton Pruitt Family Department of Biomedical Engineering (United States)

    2013-08-15

    Nanoparticle physicochemical properties such as surface charge are considered to play an important role in cellular uptake and particle-cell interactions. In order to systematically evaluate the role of surface charge on the uptake of iron oxide nanoparticles, we prepared carboxymethyl-substituted dextrans with different degrees of substitution, ranging from 38 to 5 groups per chain, and reacted them using carbodiimide chemistry with amine-silane-coated iron oxide nanoparticles with narrow size distributions in the range of 33-45 nm. Surface charge of carboxymethyl-substituted dextran-coated nanoparticles ranged from -50 to 5 mV as determined by zeta potential measurements, and was dependent on the number of carboxymethyl groups incorporated in the dextran chains. Nanoparticles were incubated with CaCo-2 human colon cancer cells. Nanoparticle-cell interactions were observed by confocal laser scanning microscopy and uptake was quantified by elemental analysis using inductively coupled plasma mass spectroscopy. Mechanisms of internalization were inferred using pharmacological inhibitors for fluid-phase, clathrin-mediated, and caveola-mediated endocytosis. Results showed increased uptake for nanoparticles with greater negative charge. Internalization patterns suggest that uptake of the most negatively charged particles occurs via non-specific interactions.

  8. From oleic acid-capped iron oxide nanoparticles to polyethyleneimine-coated single-particle magnetofectins

    Energy Technology Data Exchange (ETDEWEB)

    Cruz-Acuña, Melissa [University of Florida, J. Crayton Pruitt Family Department of Biomedical Engineering (United States); Maldonado-Camargo, Lorena [University of Florida, Department of Chemical Engineering (United States); Dobson, Jon; Rinaldi, Carlos, E-mail: carlos.rinaldi@bme.ufl.edu [University of Florida, J. Crayton Pruitt Family Department of Biomedical Engineering (United States)

    2016-09-15

    Various inorganic nanoparticle designs have been developed and used as non-viral gene carriers. Magnetic gene carriers containing polyethyleneimine (PEI), a well-known transfection agent, have been shown to improve DNA transfection speed and efficiency in the presence of applied magnetic field gradients that promote particle–cell interactions. Here we report a method to prepare iron oxide nanoparticles conjugated with PEI that: preserves the narrow size distribution of the nanoparticles, conserves magnetic properties throughout the process, and results in efficient transfection. We demonstrate the ability of the particles to electrostatically bind with DNA and transfect human cervical cancer (HeLa) cells by the use of an oscillating magnet array. Their transfection efficiency is similar to that of Lipofectamine 2000™, a commercial transfection reagent. PEI-coated particles were subjected to acidification, and acidification in the presence of salts, before DNA binding. Results show that although these pre-treatments did not affect the ability of particles to bind DNA they did significantly enhanced transfection efficiency. Finally, we show that these magnetofectins (PEI-MNP/DNA) complexes have no effect on the viability of cells at the concentrations used in the study. The systematic preparation of magnetic vectors with uniform physical and magnetic properties is critical to progressing this non-viral transfection technology.

  9. From oleic acid-capped iron oxide nanoparticles to polyethyleneimine-coated single-particle magnetofectins

    International Nuclear Information System (INIS)

    Cruz-Acuña, Melissa; Maldonado-Camargo, Lorena; Dobson, Jon; Rinaldi, Carlos

    2016-01-01

    Various inorganic nanoparticle designs have been developed and used as non-viral gene carriers. Magnetic gene carriers containing polyethyleneimine (PEI), a well-known transfection agent, have been shown to improve DNA transfection speed and efficiency in the presence of applied magnetic field gradients that promote particle–cell interactions. Here we report a method to prepare iron oxide nanoparticles conjugated with PEI that: preserves the narrow size distribution of the nanoparticles, conserves magnetic properties throughout the process, and results in efficient transfection. We demonstrate the ability of the particles to electrostatically bind with DNA and transfect human cervical cancer (HeLa) cells by the use of an oscillating magnet array. Their transfection efficiency is similar to that of Lipofectamine 2000™, a commercial transfection reagent. PEI-coated particles were subjected to acidification, and acidification in the presence of salts, before DNA binding. Results show that although these pre-treatments did not affect the ability of particles to bind DNA they did significantly enhanced transfection efficiency. Finally, we show that these magnetofectins (PEI-MNP/DNA) complexes have no effect on the viability of cells at the concentrations used in the study. The systematic preparation of magnetic vectors with uniform physical and magnetic properties is critical to progressing this non-viral transfection technology.

  10. Effect of magnetic iron oxide nanoparticles in surface water treatment: trace minerals and microbes.

    Science.gov (United States)

    Lakshmanan, Ramnath; Okoli, Chuka; Boutonnet, Magali; Järås, Sven; Rajarao, Gunaratna K

    2013-02-01

    The existing water treatment process often uses chemicals, which is of high health and environmental concern. The present study focused on the efficiency of microemulsion prepared magnetic iron oxide nanoparticles (ME-MIONs) and protein-functionalized nanoparticles (MOCP+ME-MIONs) in water treatment. Their influence on mineral ions and microorganisms present in the surface water from lake Brunnsviken and Örlången, Sweden were investigated. Ion analysis of water samples before and after treatment with nanoparticles was performed. Microbial content was analyzed by colony forming units (CFU/ml). The results impart that ME-MIONs could reduce the water turbidity even in low turbid water samples. Reduction of microbial content (98%) was observed at 37°C and more than 90% reduction was seen at RT and 30 °C when compared to untreated samples from lake Örlången. The investigated surface water treatment method with ME-MIONs was not significantly affecting the mineral ion composition, which implies their potential complement in the existing treatment process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Synthesis, characterization and theranostic evaluation of Indium-111 labeled multifunctional superparamagnetic iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Zolata, Hamidreza; Abbasi Davani, Fereydoun; Afarideh, Hossein

    2015-01-01

    Indium-111 labeled, Trastuzumab-Doxorubicin Conjugated, and APTES-PEG coated magnetic nanoparticles were designed for tumor targeting, drug delivery, controlled drug release, and dual-modal tumor imaging. Superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized by thermal decomposition method to obtain narrow size particles. To increase SPIONs circulation time in blood and decrease its cytotoxicity in healthy tissues, SPIONs surface was modified with 3-Aminopropyltriethoxy Silane (APTES) and then were functionalized with N-Hydroxysuccinimide (NHS) ester of Polyethylene Glycol Maleimide (NHS-PEG-Mal) to conjugate with thiolated 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene-3,6, 9,-triacetic acid (PCTA) bifunctional chelator (BFC) and Trastuzumab antibody. In order to tumor SPECT/MR imaging, SPIONs were labeled with Indium-111 (T 1/2 = 2.80d). NHS ester of monoethyl malonate (MEM-NHS) was used for conjugation of Doxorubicin (DOX) chemotherapeutic agent onto SPIONs surface. Mono-Ethyl Malonate allows DOX molecules to be attached to SPIONs via pH-sensitive hydrazone bonds which lead to controlled drug release in tumor region. Active and passive tumor targeting were achieved through incorporated anti-HER2 (Trastuzumab) antibody and EPR effect of solid tumors for nanoparticles respectively. In addition to in vitro assessments of modified SPIONs in SKBR3 cell lines, their theranostic effects were evaluated in HER2 + breast tumor bearing BALB/c mice via biodistribution study, dual-modal molecular imaging and tumor diameter measurements

  12. Associations between iron oxyhydroxide nanoparticle growth and metal adsorption/structural incorporation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C.S.; Lentini, C.J.; Waychunas, G.A.

    2008-09-15

    The interaction of metal ions and oxyanions with nanoscale mineral phases has not yet been extensively studied despite the increased recognition of their prevalence in natural systems as a significant component of geomedia. A combination of macroscopic uptake studies to investigate the adsorption behavior of As(V), Cu(II), Hg(II), and Zn(II) onto nanoparticulate goethite ({alpha}-FeOOH) as a function of aging time at elevated temperature (75 C) and synchrotron-based X-ray studies to track changes in both the sorption mode and the rate of nanoparticle growth reveal the effects that uptake has on particle growth. Metal(loid) species which sorb quickly to the iron oxyhydroxide particles (As(V), Cu(II)) appear to passivate the particle surface, impeding the growth of the nanoparticles with progressive aging; in contrast, species that sorb more slowly (Hg(II), Zn(II)) have considerably less impact on particle growth. Progressive changes in the speciation of these particular metals with time suggest shifts in the mode of metal uptake with time, possibly indicating structural incorporation of the metal(loid) into the nanoparticle; this is supported by the continued increase in uptake concomitant with particle growth, implying that metal species may transform from surface-sorbed species to more structurally incorporated forms. This type of incorporation would have implications for the long-term fate and mobility of metals in contaminated regions, and affect the strategy for potential remediation/modeling efforts.

  13. Evolution of the magnetic structure with chemical composition in spinel iron oxide nanoparticles.

    Science.gov (United States)

    Muscas, G; Yaacoub, N; Concas, G; Sayed, F; Sayed Hassan, R; Greneche, J M; Cannas, C; Musinu, A; Foglietti, V; Casciardi, S; Sangregorio, C; Peddis, D

    2015-08-28

    Magnetic properties of iron oxide nanoparticles with spinel structure are strictly related to a complex interplay between cationic distribution and the presence of a non-collinear spin structure (spin canting). With the aim to gain better insight into the effect of the magnetic structure on magnetic properties, in this paper we investigated a family of small crystalline ferrite nanoparticles of the formula CoxNi1-xFe2O4 (0 ≤x≤ 1) having equal size (≈4.5 nm) and spherical-like shape. The field dependence of magnetization at low temperatures indicated a clear increase of magnetocrystalline anisotropy and saturation magnetization (higher than the bulk value for CoFe2O4: ∼130 A m(2) kg(-1)) with the increase of cobalt content. The magnetic structure of nanoparticles has been investigated by Mössbauer spectroscopy under an intense magnetic field (8 T) at a low temperature (10 K). The magnetic properties have been explained in terms of an evolution of the magnetic structure with the increase of cobalt content. In addition a direct correlation between cationic distribution and spin canting has been proposed, explaining the presence of a noncollinear spin structure in terms of superexchange interaction energy produced by the average cationic distribution and vacancies in the spinel structure.

  14. Mössbauer Study of Graphite-Containing Iron Oxide Nanoparticles

    Science.gov (United States)

    Sorescu, Monica; Trotta, Richard

    2016-03-01

    Graphite-doped hematite and magnetite nanoparticles systems (~50 nm) were prepared by mechanochemical activation for milling times ranging from 2 to 12 hours. Their structural and magnetic properties were studied by 57Fe Mössbauer spectroscopy. The spectra corresponding to the hematite milled samples were analyzed by considering two sextets, corresponding to the incorporation of carbon atoms into the iron oxide structure. For ball-milling time of 12 hours a quadrupole split doublet has been added, representing the contribution of ultrafine particles. The Mössbauer spectra of graphite-doped magnetite were resolved considering a sextet and a magnetic hyperfine field distribution, corresponding to the tetrahedral and octahedral sublattices of magnetite, respectively. A quadrupole split doublet was incorporated in the fitting of the 12-hour milled sample. The recoilless fraction for all samples was determined using our previously developed dual absorber method. It was found that the recoilless fraction of the graphite-doped hematite nanoparticles decreases as function of ball-milling time. The f factor of graphite-containing magnetite nanoparticles for the tetrahedral sites stays constant, while that of the octahedral sublattice decreases as function of ball-milling time. These findings reinforce the idea that carbon atoms exhibit preference for the octahedral sites of magnetite.

  15. Effect of surface functionalisation on the interaction of iron oxide nanoparticles with polymerase chain reaction.

    Science.gov (United States)

    Aysan, Ayse Beyza; Knejzlík, Zdeněk; Ulbrich, Pavel; Šoltys, Marek; Zadražil, Aleš; Štěpánek, František

    2017-05-01

    The combination of nanoparticles with the polymerase chain reaction (PCR) can have benefits such as easier sample handling or higher sensitivity, but also drawbacks such as loss of colloidal stability or inhibition of the PCR. The present work systematically investigates the interaction of magnetic iron oxide nanoparticles (MIONs) with the PCR in terms of colloidal stability and potential PCR inhibition due to interaction between the PCR components and the nanoparticle surface. Several types of MIONs with and without surface functionalisation by sodium citrate, dextran and 3-aminopropyl-triethoxysilane (APTES) were prepared and characterised by Transmission Electron Microscopy (TEM), dynamic light scattering (DLS) and Fourier Transform Infrared (FT-IR) spectroscopy. Colloidal stability in the presence of the PCR components was investigated both at room temperature and under PCR thermo-cycling. Dextran-stabilized MIONs show the best colloidal stability in the PCR mix at both room and elevated temperatures. Citrate- and APTES-stabilised as well as uncoated MIONs show a comparable PCR inhibition near the concentration 0.1mgml -1 while the inhibition of dextran stabilized MIONs became apparent near 0.5mgml -1 . It was demonstrated that the PCR could be effectively carried out even in the presence of elevated concentration of MIONs up to 2mgml -1 by choosing the right coating approach and supplementing the reaction mix by critical components, Taq DNA polymerase and Mg 2+ ions. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Rapid and controlled transformation of nitrate in water and brine by stabilized iron nanoparticles

    International Nuclear Information System (INIS)

    Xiong Zhong; Zhao Dongye; Pan Gang

    2009-01-01

    Highly reactive zero-valent iron (ZVI) nanoparticles stabilized with carboxymethyl cellulose (CMC) were tested for reduction of nitrate in fresh water and brine. Batch kinetic tests showed that the pseudo first-order rate constant (k obs ) with the stabilized nanoparticles was five times greater than that for non-stabilized counterparts. The stabilizer not only increased the specific surface area of the nanoparticles, but also increased the reactive particle surface. The allocation between the two reduction products, NH 4 + and N 2 , can be manipulated by varying the ZVI-to-nitrate molar ratio and/or applying a Cu-Pd bimetallic catalyst. Greater CMC-to-ZVI ratios lead to faster nitrate reduction. Application of a 0.05 M HEPES buffer increased the k obs value by 15 times compared to that without pH control. Although the presence of 6% NaCl decreased k obs by 30%, 100% nitrate was transformed within 2 h in the saline water. The technology provides a powerful alternative for treating water with concentrated nitrate such as ion exchange brine.

  17. Iron

    DEFF Research Database (Denmark)

    Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

    2014-01-01

    The interest in the role of ferrous iron in diabetes pathophysiology has been revived by recent evidence of iron as an important determinant of pancreatic islet inflammation and as a biomarker of diabetes risk and mortality. The iron metabolism in the β-cell is complex. Excess free iron is toxic......, but at the same time, iron is required for normal β-cell function and thereby glucose homeostasis. In the pathogenesis of diabetes, iron generates reactive oxygen species (ROS) by participating in the Fenton chemistry, which can induce oxidative damage and apoptosis. The aim of this review is to present...... and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation by activation...

  18. Methodology description for detection of cellular uptake of PVA coated superparamagnetic iron oxide nanoparticles (SPION) in synovial cells of sheep

    Energy Technology Data Exchange (ETDEWEB)

    Schoepf, Bernhard [Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty Zurich, University of Zurich, Winterthurerstr. 260, 8057 Zurich (Switzerland); Neuberger, Tobias [Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty Zurich, University of Zurich, Winterthurerstr. 260, 8057 Zurich (Switzerland); Schulze, Katja [Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty Zurich, University of Zurich, Winterthurerstr. 260, 8057 Zurich (Switzerland); Petri, Alke [Powder Technology Laboratory, Institute of Materials, Swiss Federal Institute of Technology Lausanne, EPFL, MX-D Ecublens, 1015 Lausanne (Switzerland); Chastellain, Matthieu [Powder Technology Laboratory, Institute of Materials, Swiss Federal Institute of Technology Lausanne, EPFL, MX-D Ecublens, 1015 Lausanne (Switzerland); Hofmann, Margarete [MatSearch, Ch. Jean Pavillard 14, 1009 Pully (Switzerland); Hofmann, Heinrich [Powder Technology Laboratory, Institute of Materials, Swiss Federal Institute of Technology Lausanne, EPFL, MX-D Ecublens, 1015 Lausanne (Switzerland); Rechenberg, Brigitte von [Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty Zurich, University of Zurich, Winterthurerstr. 260, 8057 Zurich (Switzerland)]. E-mail: bvonrechenberg@vetclinics.unizh.ch

    2005-05-15

    The detection of superparamagnetic iron oxide nanoparticles (SPION) in synoviocytes is reported. Synoviocytes were incubated for 2, 12, 24 and 48 h with 1.5 mg/ml of PVA coated SPION under the influence of magnets (12 h). Particles were well tolerated by the synoviocytes, were easily detected using the Turnbulls and Prussian blue reactions between 12 and 24 h.

  19. A Mössbauer study of the chemical stability of iron oxide nanoparticles in PMMA and PVB beads

    DEFF Research Database (Denmark)

    Chen, Wei; Mørup, Steen; Hansen, Mikkel Fougt

    2008-01-01

    We have prepared magnetic beads consisting of iron oxide nanoparticles in a polymethyl methacrylate (PMMA) and a polyvinyl butyral (PVB) matrix. High-field Mossbauer studies show that the particles have an almost perfect collinear spin structure and magnetization measurements show that they are s...

  20. Influence of different synthesis approach on doping behavior of silver nanoparticles onto the iron oxide-silica coreshell surfaces

    Czech Academy of Sciences Publication Activity Database

    Mahmed, N.; Jiang, H.; Heczko, Oleg; Söderberg, O.; Hannula, S.-P.

    2012-01-01

    Roč. 14, č. 8 (2012), s. 1-15 ISSN 1388-0764 Institutional research plan: CEZ:AV0Z10100520 Keywords : stroble method * silver nanoparticles * iron oxide * amourphous silica Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.175, year: 2012

  1. Enhancement of irradiation effects on cancer cells by cross-linked dextran-coated iron oxide (CLIO) nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F-K; Chen, W-C; Lai, S-F [Department of Chemical and Materials Engineering, National Yunlin University of Science and Technology, 123, University Rd, Sec. 3, Douliu, Yunlin 64002, Taiwan (China); Liu, C-J; Wang, C-L; Wang, C-H; Chen, H-H; Hua, T-E; Cheng, Y-Y; Wu, M K; Hwu, Y [Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan (China); Yang, C-S [Center for Nanomedicine Research, National Helath Research Institute, Miaoli 350, Taiwan (China); Margaritondo, G [Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)], E-mail: chenwc@yuntech.edu.tw, E-mail: giorgio.margaritondo@epfl.ch

    2010-01-21

    We investigated iron oxide nanoparticles with two different surface modifications, dextran coating and cross-linked dextran coating, showing that their different internalization affects their capability to enhance radiation damage to cancer cells. The internalization was monitored with an ultrahigh resolution transmission x-ray microscope (TXM), indicating that the differences in the particle surface charge play an essential role and dominate the particle-cell interaction. We found that dextran-coated iron oxide nanoparticles cannot be internalized by HeLa and EMT-6 cells without being functionalized with amino groups (the cross-linked dextran coating) that modify the surface potential from -18 mV to 13.4 mV. The amount of cross-linked dextran-coated iron oxide nanoparticles uptaken by cancer cells reached its maximum, 1.33 x 10{sup 9} per HeLa cell, when the co-culture concentration was 40 {mu}g Fe mL{sup -1} or more. Standard tests indicated that these internalized nanoparticles increased the damaging effects of x-ray irradiation, whereas they are by themselves biocompatible. These results could lead to interesting therapy applications; furthermore, iron oxide also produces high contrast for magnetic resonance imaging (MRI) in the diagnosis and therapy stages.

  2. In situ growth of capping-free magnetic iron oxide nanoparticles on liquid-phase exfoliated graphene

    NARCIS (Netherlands)

    Tsoufis, T.; Syrgiannis, Z.; Akhtar, N.; Prato, M.; Katsaros, F.; Sideratou, Z.; Kouloumpis, A.; Gournis, D.; Rudolf, P.

    2015-01-01

    We report a facile approach for the in situ synthesis of very small iron oxide nanoparticles on the surface of high-quality graphene sheets. Our synthetic strategy involved the direct, liquid-phase exfoliation of highly crystalline graphite (avoiding any oxidation treatment) and the subsequent

  3. Superparamagnetic iron oxide nanoparticles alter expression of obesity and T2D-associated risk genes in human adipocytes

    NARCIS (Netherlands)

    Sharifi, S.; Daghighi, S.; Motazacker, M. M.; Badlou, B.; Sanjabi, B.; Akbarkhanzadeh, A.; Rowshani, A. T.; Laurent, S.; Peppelenbosch, M. P.; Rezaee, F.

    2013-01-01

    Adipocytes hypertrophy is the main cause of obesity and its affliction such as type 2 diabetes (T2D). Since superparamagnetic iron oxide nanoparticles (SPIONs) are used for a wide range of biomedical/medical applications, we aimed to study the effect of SPIONs on 22 and 29 risk genes (Based on gene

  4. Magnetic targeting of surface-modified superparamagnetic iron oxide nanoparticles yields antibacterial efficacy against biofilms of gentamicin-resistant staphylococci

    NARCIS (Netherlands)

    Subbiandoss, Guruprakash; Sharifi, Shahriar; Grijpma, Dirk W.; Laurent, Sophie; van der Mei, Henny C.; Mahmoudi, Morteza; Busscher, Henk J.

    Biofilms on biomaterial implants are hard to eradicate with antibiotics due to the protection offered by the biofilm mode of growth, especially when caused by antibiotic-resistant strains. Superparamagnetic iron oxide nanoparticles (SPIONs) are widely used in various biomedical applications, such as

  5. Magnetic targeting of surface-modified superparamagnetic iron oxide nanoparticles yields antibacterial efficacy against biofilms of gentamicin-resistant staphylococci

    NARCIS (Netherlands)

    Subbiahdoss, G.; Sharifi, Shahriar; Grijpma, Dirk W.; Laurent, S.; van der Mei, H.C.; Mahmoudi, M.; Busscher, H.J.

    2012-01-01

    Biofilms on biomaterial implants are hard to eradicate with antibiotics due to the protection offered by the biofilm mode of growth, especially when caused by antibiotic-resistant strains. Superparamagnetic iron oxide nanoparticles (SPIONs) are widely used in various biomedical applications, such as

  6. Polymer-grafted superparamagnetic iron oxide nanoparticles as a potential stable system for magnetic resonance imaging and doxorubicin delivery

    NARCIS (Netherlands)

    Asadi, H.; Khoee, S.; Deckers, R.

    2016-01-01

    Currently, there is high interest in developing multifunctional theranostic platforms with both imaging and therapeutic functions. Herein, we report a facile approach to develop polymer-grafted superparamagnetic iron oxide nanoparticles (SPIONs) as a promising system for imaging and drug delivery. A

  7. Solvent-Free Esterification of Carboxylic Acids Using Supported Iron Oxide Nanoparticles as an Efficient and Recoverable Catalyst

    Directory of Open Access Journals (Sweden)

    Fatemeh Rajabi

    2016-07-01

    Full Text Available Supported iron oxide nanoparticles on mesoporous materials (FeNP@SBA-15 have been successfully utilized in the esterification of a variety carboxylic acids including aromatic, aliphatic, and long-chain carboxylic acids under convenient reaction conditions. The supported catalyst could be easily recovered after reaction completion and reused several times without any loss in activity after up to 10 runs.

  8. Magnetic properties of iron/graphite core-shell nanoparticles prepared by annealing of Fe-C-N-based nanocomposite

    Czech Academy of Sciences Publication Activity Database

    David, Bohumil; Pizúrová, Naděžda; Schneeweiss, Oldřich; Bezdička, Petr; Alexandrescu, R.; Morjan, I.; Cruneteanu, A.; Voicu, I.

    290-291, - (2005), s. 179-182 ISSN 0304-8853 R&D Projects: GA ČR(CZ) GA202/04/0221; GA AV ČR(CZ) KSK1010104 Institutional research plan: CEZ:AV0Z20410507 Keywords : magnetism * iron * nanoparticle Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.985, year: 2005

  9. Cerium oxide and iron oxide nanoparticles abolish the antibacterial activity of ciprofloxacin against gram positive and gram negative biofilm bacteria.

    Science.gov (United States)

    Masadeh, Majed M; Karasneh, Ghadah A; Al-Akhras, Mohammad A; Albiss, Borhan A; Aljarah, Khaled M; Al-Azzam, Sayer I; Alzoubi, Karem H

    2015-05-01

    Metal oxide nanoparticles have been suggested as good candidates for the development of antibacterial agents. Cerium oxide (CeO2) and iron oxide (Fe2O3) nanoparticles have been utilized in a number of biomedical applications. Here, the antibacterial activity of CeO2 and Fe2O3 nanoparticles were evaluated on a panel of gram positive and gram negative bacteria in both the planktonic and biofilm cultures. Additionally, the effect of combining CeO2 and Fe2O3 nanoparticles with the broad spectrum antibiotic ciprofloxacin on tested bacteria was investigated. Thus, minimum inhibitory concentrations (MICs) of CeO2 and Fe2O3 nanoparticles that are required to inhibit bacterial planktonic growth and bacterial biofilm, were evaluated, and were compared to the MICs of the broad spectrum antibiotic ciprofloxacin alone or in the presence of CeO2 and Fe2O3 nanoparticles. Results of this study show that both CeO2 and Fe2O3 nanoparticles fail to inhibit bacterial growth and biofilm biomass for all the bacterial strains tested. Moreover, adding CeO2 or Fe2O3 nanoparticles to the broad spectrum antibiotic ciprofloxacin almost abolished its antibacterial activity. Results of this study suggest that CeO2 and Fe2O3 nanoparticles are not good candidates as antibacterial agents, and they could interfere with the activity of important antibiotics.

  10. Nonspecific targeting of iron oxide nanoparticles to the liver, kidney and spleen: A novel approach to achieving specificity

    Science.gov (United States)

    Palihawadana Arachchige, Maheshika; Flack, Amanda; Chen, Xuequn; Li, Jing; Oupicky, David; Cheng, Y.-C. Norman; Shen, Yimin; Jena, Bhanu; Lawes, Gavin

    2013-03-01

    Recently, there has been significant interest in developing Fe3O4 nanoparticles for biomedical applications including targeted drug delivery and magnetic resonance imaging. One of the major problems in these applications is the undesirable filtration of these materials by the mononuclear phagocyte system. Preliminary magnetic resonance imaging and magnetization studies on hyaluronic acid coated nanoparticles injected intravenously into mice confirm that the nanoparticles accumulate in the liver, spleen, and kidneys. To identify whether certain specific proteins are responsible for nanoparticle accumulation in these organs, we exposed hyaluronic acid coated nanoparticles to proteins extracted from the liver, spleen, and kidneys, together with blood plasma proteins, then subsequently used gel electrophoresis and mass spectroscopy to identify the proteins binding to the nanoparticles. We find that the unwanted accumulation of nanoparticles in these organs can potentially be attributed to specific binding by a small number of proteins. By appropriately functionalizing the iron oxide nanoparticles, we expect that the nanoparticles uptake in the liver, spleen, and kidneys will be reduced.

  11. Enhancement of Degradation and Dechlorination of Trichloroethylene via Supporting Palladium/Iron Bimetallic Nanoparticles onto Mesoporous Silica

    Directory of Open Access Journals (Sweden)

    Jianjun Wei

    2016-07-01

    Full Text Available This study is aimed to prevent the agglomeration of Pd/Fe bimetallic nanoparticles and thus improve the efficiency toward degradation and dechlorination of chlorinated organic contaminants. A mesoporous silica with a primary pore diameter of 8.3 nm and a specific surface area of 688 m2/g was prepared and used as the host of Pd/Fe nanoparticles. The Pd/Fe nanoparticles were deposited onto or into the mesoporous silica by reduction of ferrous ion and hexachloropalladate ion in aqueous phase. Batch degradation and dechlorination reactions of trichloroethylene were conducted with initial trichloroethylene concentration of 23.7 mg/L, iron loading of 203 or 1.91 × 103 mg/L and silica loading of 8.10 g/L at 25 °C. Concentration of trichloroethylene occurs on the supported Pd/Fe nanoparticles, with trichloroethylene degrading to 56% and 59% in 30 min on the supported Pd/Fe nanoparticles with weight percentage of palladium to iron at 0.075% and 0.10% respectively. The supported Pd/Fe nanoparticles exhibit better dechlorination activity. When the supported Pd/Fe nanoparticles with a weight percentage of palladium to iron of 0.10% were loaded much less than the bare counterpart, the yield of ethylene plus ethane in 10 h on them was comparable, i.e., 19% vs. 21%. This study offers a future approach to efficiently combine the reactivity of supported Pd/Fe nanoparticles and the adsorption ability of mesoporous silica.

  12. The influence of iron oxide nanoparticles upon the adsorption of organic matter on magnetic powdered activated carbon.

    Science.gov (United States)

    Lompe, Kim Maren; Menard, David; Barbeau, Benoit

    2017-10-15

    Combining powdered activated carbon (PAC) with magnetic iron oxides has been proposed in the past to produce adsorbents for natural organic matter (NOM) removal that can be easily separated using a magnetic field. However, the trade-off between the iron oxides' benefits and the reduced carbon content, porosity, and surface area has not yet been investigated systematically. We produced 3 magnetic powdered activated carbons (MPAC) with mass fractions of 10%, 38% and 54% maghemite nanoparticles and compared them to bare PAC and pure nanoparticles with respect to NOM adsorption kinetics and isotherms. While adsorption kinetics were not influenced by the presence of the iron oxide nanoparticles (IONP), as shown by calculated diffusion coefficients from the homogeneous surface diffusion model, nanoparticles reduced the adsorption capacity of NOM due to their lower adsorption capacity. Although the nanoparticles added mesoporosity to the composite materials they blocked intrinsic PAC mesopores at mass fractions >38% as measured by N 2 -adsorption isotherms. Below this mass fraction, the adsorption capacity was mainly dependent on the carbon content in MPAC and mesopore blocking was negligible. If NOM adsorption with MPAC is desired, a highly mesoporous PAC and a low IONP mass fraction should be chosen during MPAC synthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. The effect of cryoprotection on the use of PLGA encapsulated iron oxide nanoparticles for magnetic cell labeling

    International Nuclear Information System (INIS)

    Tang, Kevin S; Shapiro, Erik M; Hashmi, Sarah M

    2013-01-01

    Magnetic PLGA nanoparticles are a significant advancement in the quest to translate MRI-based cell tracking to the clinic. The benefits of these types of particles are that they encapsulate large amounts of iron oxide nanocrystals within an FDA-approved polymer matrix, combining the best aspects of inert micron-sized iron oxide particles, or MPIOs, and biodegradable small particles of iron oxide, or SPIOs. Practically, PLGA nanoparticle fabrication and storage requires some form of cryoprotectant to both protect the particle during freeze drying and to promote resuspension. While this is a commonly employed procedure in the fabrication of drug loaded PLGA nanoparticles, it has yet to be investigated for magnetic particles and what effect this might have on internalization of magnetic particles. As such, in this study, magnetic PLGA nanoparticles were fabricated with various concentrations of two common cryoprotectants, dextrose and sucrose, and analyzed for their ability to magnetically label cells. It was found that cryoprotection with either sugar significantly enhanced the ability to resuspend nanoparticles without aggregation. Magnetic cell labeling was impacted by sugar concentration, with higher sugar concentrations used during freeze drying more significantly reducing magnetic cell labeling than lower concentrations. These studies suggest that cryoprotection with 1% dextrose is an optimal compromise that preserves monodispersity following resuspension and high magnetic cell labeling. (paper)

  14. Dextran and Polymer Polyethylene Glycol (PEG Coating Reduce Both 5 and 30 nm Iron Oxide Nanoparticle Cytotoxicity in 2D and 3D Cell Culture

    Directory of Open Access Journals (Sweden)

    Alisa Morss Clyne

    2012-05-01

    Full Text Available Superparamagnetic iron oxide nanoparticles are widely used in biomedical applications, yet questions remain regarding the effect of nanoparticle size and coating on nanoparticle cytotoxicity. In this study, porcine aortic endothelial cells were exposed to 5 and 30 nm diameter iron oxide nanoparticles coated with either the polysaccharide, dextran, or the polymer polyethylene glycol (PEG. Nanoparticle uptake, cytotoxicity, reactive oxygen species (ROS formation, and cell morphology changes were measured. Endothelial cells took up nanoparticles of all sizes and coatings in a dose dependent manner, and intracellular nanoparticles remained clustered in cytoplasmic vacuoles. Bare nanoparticles in both sizes induced a more than 6 fold increase in cell death at the highest concentration (0.5 mg/mL and led to significant cell elongation, whereas cell viability and morphology remained constant with coated nanoparticles. While bare 30 nm nanoparticles induced significant ROS formation, neither 5 nm nanoparticles (bare or coated nor 30 nm coated nanoparticles changed ROS levels. Furthermore, nanoparticles were more toxic at lower concentrations when cells were cultured within 3D gels. These results indicate that both dextran and PEG coatings reduce nanoparticle cytotoxicity, however different mechanisms may be important for different size nanoparticles.

  15. Dextran and Polymer Polyethylene Glycol (PEG) Coating Reduce Both 5 and 30 nm Iron Oxide Nanoparticle Cytotoxicity in 2D and 3D Cell Culture

    Science.gov (United States)

    Yu, Miao; Huang, Shaohui; Yu, Kevin Jun; Clyne, Alisa Morss

    2012-01-01

    Superparamagnetic iron oxide nanoparticles are widely used in biomedical applications, yet questions remain regarding the effect of nanoparticle size and coating on nanoparticle cytotoxicity. In this study, porcine aortic endothelial cells were exposed to 5 and 30 nm diameter iron oxide nanoparticles coated with either the polysaccharide, dextran, or the polymer polyethylene glycol (PEG). Nanoparticle uptake, cytotoxicity, reactive oxygen species (ROS) formation, and cell morphology changes were measured. Endothelial cells took up nanoparticles of all sizes and coatings in a dose dependent manner, and intracellular nanoparticles remained clustered in cytoplasmic vacuoles. Bare nanoparticles in both sizes induced a more than 6 fold increase in cell death at the highest concentration (0.5 mg/mL) and led to significant cell elongation, whereas cell viability and morphology remained constant with coated nanoparticles. While bare 30 nm nanoparticles induced significant ROS formation, neither 5 nm nanoparticles (bare or coated) nor 30 nm coated nanoparticles changed ROS levels. Furthermore, nanoparticles were more toxic at lower concentrations when cells were cultured within 3D gels. These results indicate that both dextran and PEG coatings reduce nanoparticle cytotoxicity, however different mechanisms may be important for different size nanoparticles. PMID:22754315

  16. Adsorption of superparamagnetic iron oxide nanoparticles on silica and calcium carbonate sand.

    Science.gov (United States)

    Park, Yoonjee C; Paulsen, Jeffrey; Nap, Rikkert J; Whitaker, Ragnhild D; Mathiyazhagan, Vidhya; Song, Yi-Qiao; Hürlimann, Martin; Szleifer, Igal; Wong, Joyce Y

    2014-01-28

    Superparamagnetic iron oxide (SPIO) nanoparticles have the potential to be used in the characterization of porous rock formations in oil fields as a contrast agent for NMR logging because they are small enough to traverse through nanopores and enhance contrast by shortening NMR T2 relaxation time. However, successful development and application require detailed knowledge of particle stability and mobility in reservoir rocks. Because nanoparticle adsorption to sand (SiO2) and rock (often CaCO3) affects their mobility, we investigated the thermodynamic equilibrium adsorption behavior of citric acid-coated SPIO nanoparticles (CA SPIO NPs) and poly(ethylene glycol)-grafted SPIO nanoparticles (PEG SPIO NPs) on SiO2 (silica) and CaCO3 (calcium carbonate). Adsorption behavior was determined at various pH and salt conditions via chemical analysis and NMR, and the results were compared with molecular theory predictions. Most of the NPs were recovered from silica, whereas far fewer NPs were recovered from calcium carbonate because of differences in the mineral surface properties. NP adsorption increased with increasing salt concentration: this trend was qualitatively explained by molecular theory, as was the role of the PEG grafting in preventing NPs adsorption. Quantitative disagreement between the theoretical predictions and the data was due to NP aggregation, especially at high salt concentration and in the presence of calcium carbonate. Upon aggregation, NP concentrations as determined by NMR T2 were initially overestimated and subsequently corrected using the relaxation rate 1/T2, which is a function of aggregate size and fractal dimension of the aggregate. Our experimental validation of the theoretical predictions of NP adsorption to minerals in the absence of aggregation at various pH and salt conditions demonstrates that molecular theory can be used to determine interactions between NPs and relevant reservoir surfaces. Importantly, this integrated experimental and

  17. Characterisation of iron oxide nanoparticles by Mössbauer spectroscopy at ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Joos, Alexander; Rümenapp, Christine [Zentralinstitut für Medizintechnik (IMETUM), Technische Universität München, Boltzmannstraße 11, 85748 Garching (Germany); Wagner, Friedrich E. [Physik-Department E15, Technische Universität München, James-Franck-Straße 1, 85748 Garching (Germany); Gleich, Bernhard, E-mail: gleich@tum.de [Zentralinstitut für Medizintechnik (IMETUM), Technische Universität München, Boltzmannstraße 11, 85748 Garching (Germany)

    2016-02-01

    Magnetite (Fe{sub 3}O{sub 4}) nanoparticles are important as contrast agents in magnetic resonance imaging or for magnetic drug targeting. Such particles can be made by different ways of synthesis, but depending on their size they tend to oxidise to maghemite (γ-Fe{sub 2}O{sub 3}), which is often less desirable because of its lower magnetisation. Mössbauer spectroscopy is well suited for determining the relative amounts of the two iron oxides in a sample. When measured at 4.2 K the nanoparticles typically exhibit well-defined but complicated hyperfine spectra that may present some problems of evaluation, but eventually yield reliable results for the degree of oxdation. At room temperature, however, particles smaller than about 15 nm are affected by superparamagnetic relaxation, which renders Mössbauer spectroscopy useless for their characterisation. To characterise magnetic nanoparticles even at room temperature, we designed an arrangement of permanent magnets to apply an external magnetic field of about 0.7 T to the Mössbauer absorbers. This has been found to be sufficient to give rise to magnetically split Mössbauer spectra that allow a distinction between magnetite and maghemite and to determine their relative amounts in a sample. - Highlights: • Mössbauer spectroscopy can be used to characterise magnetic nanoparticles (MNP). • Interpretation of room temperature spectra of MNP smaller than 15 nm is impossible. • We built a permanent magnet construction to apply a homogeneous field of 725 mT. • This field is enough to generate useful spectra of the MNP even at room temperature. • The magnetite content of small MNP can thus be determined.

  18. Preparation of composite with silica-coated nanoparticles of iron oxide spinels for applications based on magnetically induced hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Angela L. [Federal University of Ouro Preto (UFOP), Department of Chemistry (Brazil); Fabris, Jose D., E-mail: jdfabris@ufmg.br [Federal University of Jequitinhonha and Mucuri Valleys (UFVJM) (Brazil); Pereira, Marcio C. [Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Institute of Science, Engineering and Technology (Brazil); Domingues, Rosana Z. [Federal University of Minas Gerais (UFMG), Department of Chemistry (Brazil); Ardisson, Jose D. [Development Center of Nuclear Technology (CNEN/CDTN), Laboratory of Applied Physics (Brazil)

    2013-04-15

    It is reported a novel method to prepare magnetic core (iron oxide spinels)-shell (silica) composites containing well-dispersed magnetic nanoparticles in aqueous solution. The synthetic process consists of two steps. In a first step, iron oxide nanoparticles obtained through co-precipitation are dispersed in an aqueous solution containing tetramethylammonium hydroxide; in a second step, particles of this sample are coated with silica, through hydrolyzation of tetraethyl orthosilicate. The intrinsic atomic structure and essential properties of the core-shell system were assessed with powder X-ray diffraction, Fourier transform infrared spectrometry, Moessbauer spectroscopy and transmission electron microscopy. The heat released by this ferrofluid under an AC-generated magnetic field was evaluated by following the temperature evolution under increasing magnetic field strengths. Results strongly indicate that this ferrofluid based on silica-coated iron oxide spinels is technologically a very promising material to be used in medical practices, in oncology.

  19. Iron oxide nanoparticle layer templated by polydopamine spheres: a novel scaffold toward hollow-mesoporous magnetic nanoreactors.

    Science.gov (United States)

    Huang, Liang; Ao, Lijiao; Xie, Xiaobin; Gao, Guanhui; Foda, Mohamed F; Su, Wu

    2015-01-14

    Superparamagnetic iron oxide nanoparticle layers with high packing density and controlled thickness were in situ deposited on metal-affinity organic templates (polydopamine spheres), via one-pot thermal decomposition. The as synthesized hybrid structure served as a facile nano-scaffold toward hollow-mesoporous magnetic carriers, through surfactant-assisted silica encapsulation and its subsequent calcination. Confined but accessible gold nanoparticles were successfully incorporated into these carriers to form a recyclable catalyst, showing quick magnetic response and a large surface area (642.5 m(2) g(-1)). Current nano-reactors exhibit excellent catalytic performance and high stability in reduction of 4-nitrophenol, together with convenient magnetic separability and good reusability. The integration of compact iron oxide nanoparticle layers with programmable polydopamine templates paves the way to fabricate magnetic-response hollow structures, with high permeability and multi-functionality.

  20. A single exposure to iron oxide nanoparticles attenuates antigen-specific antibody production and T-cell reactivity in ovalbumin-sensitized BALB/c mice

    Directory of Open Access Journals (Sweden)

    Shen CC

    2011-06-01

    Full Text Available Chien-Chang Shen1, Chia-Chi Wang1, Mei-Hsiu Liao2, Tong-Rong Jan11Department and Graduate Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan; 2Division of Isotope Application, Institute of Energy Research, Taoyuan, TaiwanBackground: Superparamagnetic iron oxide nanoparticles have been used in clinical applications as a diagnostic contrasting agent. Previous studies showed that iron oxide nanoparticles deposited in the liver and spleen after systemic administration. The present study investigated the effect of iron oxide nanoparticles on antigen-specific immune responses in mice sensitized with the T cell-dependent antigen ovalbumin (OVA.Methods: BALB/c mice were intravenously administered with a single dose of iron oxide nanoparticles (10-60 mg Fe/kg 1 hour prior to OVA sensitization, and the serum antibody production and splenocyte reactivity were examined 7 days later.Results: The serum levels of OVA-specific IgG1 and IgG2a were significantly attenuated by treatment with iron oxide nanoparticles. The production of interferon-γ and interleukin-4 by splenocytes re-stimulated with OVA in culture was robustly suppressed in mice administered with iron oxide nanoparticles. The viability of OVA-stimulated splenocytes was also attenuated. In contrast, treatment with iron oxide nanoparticles did not affect the viability of splenocytes stimulated with concanavalin A, a T-cell mitogen.Conclusion: Collectively, these data indicate that systemic exposure to a single dose of iron oxide nanoparticles compromises subsequent antigen-specific immune reactions, including the serum production of antigen-specific antibodies, and the functionality of T cells.Keywords: iron oxide nanoparticle, antigen-specific, immune, ovalbumin

  1. Synthesis and characterization of conditioned carbon with iron nanoparticles for the arsenic removal in aqueous phase

    International Nuclear Information System (INIS)

    Flores C, D. O.

    2012-01-01

    Using pineapple husks conditioned with carboxymethylcellulose, hexamine and ferric nitrate, a carbonaceous material was obtained with nanoparticles of Fe (C Fe), which was characterized and tested for arsenic removal in the aqueous phase. The microscopic study showed spheres 4 microns and filaments 100 nm wide, so as iron particles whose diameter decreases to an average of 38.81 nm, when pyrolysis time was increased to 180 min. their distribution in the carbonaceous matrix is homogeneous. According to energy dispersive X-ray spectroscopy, C Fe contains C (82.29%), O (7.23%), K (0.68%), Ca (3.77%) and Fe (6.25%) and its diffraction pattern shows the characteristic peak of Fe (0), which is not observed in the coal without iron. By neutron activation analysis were quantified Al, Br, Ce, Co, Cr, Cs, Eu, Hf, K, Mg, Mn, Na, Rb, Sb, Sc and Zn, they can be involved in the process of sorption of As (v) forming surface active sites. For C Fe and C B characterized by Fourier transform infrared spectrometry, groups C-H, C=O, C=C, -Nh, NH 2 , isocyanate and isonitrile were found, the last two were formed by the present hexamine. X-ray photoelectron spectroscopy showed energy states of C 1 and O 1 in pineapple shell washed, shell conditioned with iron, C Fe at different times and the pyrolysis coal without iron (C B). The material C Fe 180 presented a specific area of 167 m 2 /g and 7.12 ± 1 sites/nm 2 isoelectric point while pH i = 11.1 C B is 98.80 m 2 /g specific area and 1.5 ± 1 sites/nm 2 and pH i = 10.6, being favorable to the sorption process. The highest removal of As(v) for both materials was at ph = 2, fitting the kinetic data to pseudo-second order model. The isotherms as a function of concentration were adjusted to Freundlich model indicating multilayer chemisorption at specific sites of a heterogeneous medium. Characterization by scanning electron microscopy after the sample sorption Fe nanoparticles remain in the carbonaceous matrix being not affected by the

  2. Evaluation of umbilical cord mesenchymal stem cell labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-lysine

    Directory of Open Access Journals (Sweden)

    Tatiana Taís Sibov

    2012-06-01

    Full Text Available Objective: The objective of this study was to evaluate the effect of thelabeling of umbilical cord vein derived mesenchymal stem cells withsuperparamagnetic iron oxide nanoparticles coated with dextran andcomplexed to a non-viral transfector agent transfector poly-L-lysine.Methods: The labeling of mesenchymal stem cells was performedusing the superparamagnetic iron oxide nanoparticles/dextrancomplexed and not complexed to poly-L-lysine. Superparamagneticiron oxide nanoparticles/dextran was incubated with poly-L-lysine inan ultrasonic sonicator at 37°C for 10 minutes for complex formationsuperparamagnetic iron oxide nanoparticles/dextran/poly-L-lysineby electrostatic interaction. Then, the mesenchymal stem cellswere incubated overnight with the complex superparamagnetic ironoxide nanoparticles/dextran/poly-L-lysine and superparamagneticiron oxide nanoparticles/dextran. After the incubation period themesenchymal stem cells were evaluated by internalization of thecomplex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran byPrussian Blue stain. Cellular viability of labeled mesenchymal stemcells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detectionby Annexin V- Propidium Iodide assay. Results: mesenchymalstem cells labeled with superparamagnetic iron oxide nanoparticles/dextran without poly-L-lysine not internalized efficiently thesuperparamagnetic iron oxide nanoparticles due to its low presencedetected within cells. Mesenchymal stem cells labeled with thecomplex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine efficiently internalized the superparamagnetic iron oxidenanoparticles due to greater presence in the cells interior. The viabilityand apoptosis assays demonstrated that the mesenchymal stemcells labeled and not labeled respectively with the superparamagneticiron oxide nanoparticles

  3. Standardization of Alternative Methods for Nano genotoxicity Testing in Drosophila melanogaster Using Iron Nanoparticles: A Promising Link to Nanodosimetry

    International Nuclear Information System (INIS)

    Parvathi, D. P.; Rajagopal, K.; Sumitha, R.

    2016-01-01

    The remarkable advancement of nano technology has triggered enormous production of metal nanoparticles and nano materials for diverse applications in clinical diagnostics and biomedical research. Nano technology has facilitated understanding and analysing nano toxicology in a holistic approach. Iron nanoparticles have been of special interest in recent research owing to their dynamic, paramagnetic, and catalytic properties. Research studies (in vitro model) have demonstrated the lack of toxicity in nano iron. The present study design involves in vivo toxicity assessment of nano iron at specific concentrations of 0.1mM, 1 mM, 5 mM, and 10 mM in Drosophila. DNA fragmentation assay in exposed and F1 population showed first-line toxicity to flies. Viability and reproductive ability were assessed at 24-hour and 48-hour intervals and thus indicated no statistical significance between the exposed and control groups. The wing spot assay has expressed transparent lack of toxicity in the studied concentrations of nano iron. Protein profiling has demonstrated that the protein profiles have been intact in the larvae which confirm lack of toxicity of nano iron. This leads to concluding that nano iron at the defined concentrations is neither genotoxic nor mutagenic.

  4. Carbon-encapsulated nickel-iron nanoparticles supported on nickel foam as a catalyst electrode for urea electrolysis

    International Nuclear Information System (INIS)

    Wu, Mao-Sung; Jao, Chi-Yu; Chuang, Farn-Yih; Chen, Fang-Yi

    2017-01-01

    Highlights: • Electrochemical process can purify the urea-rich wastewater, producing hydrogen gas. • Carbon-encapsulated nickel iron nanoparticles (CE-NiFe) are prepared by pyrolysis. • An ultra-thin layer of CE-NiFe nanoparticles is attached to the 3D Ni foam. • CE-NiFe nanoparticles escalate both the urea electrolysis and hydrogen evolution. - Abstract: A cyanide-bridged bimetallic coordination polymer, nickel hexacyanoferrate, could be pyrolyzed to form carbon-encapsulated nickel-iron (CE-NiFe) nanoparticles. The formation of nitrogen-doped spherical carbon shell with ordered mesoporous structure prevented the structural damage of catalyst cores and allowed the migration and diffusion of electrolyte into the hollow carbon spheres. An ultra-thin layer of CE-NiFe nanoparticles could be tightly attached to the three-dimensional macroporous nickel foam (NF) by electrophoretic deposition. The CE-NiFe nanoparticles could lower the onset potential and increase the current density in anodic urea electrolysis and cathodic hydrogen production as compared with bare NF. Macroporous NF substrate was very useful for the urea electrolysis and hydrogen production, which allowed for fast transport of electron, electrolyte, and gas products. The superior electrocatalytic ability of CE-NiFe/NF electrode in urea oxidation and water reduction made it favorable for versatile applications such as water treatment, hydrogen generation, and fuel cells.

  5. Effect of surface charge and agglomerate degree of magnetic iron oxide nanoparticles on KB cellular uptake in vitro.

    Science.gov (United States)

    Ge, Yuqing; Zhang, Yu; Xia, Jingguang; Ma, Ming; He, Shiying; Nie, Fang; Gu, Ning

    2009-10-15

    We synthesized three types of magnetic iron oxide nanoparticles (MNPs), which were meso-2,3-dimercaptosuccinic acid (DMSA) coated MNPs (DMSA@MNPs, 17.3+/-4.8 nm, negative charge), chitosan (CS) coated MNPs (CS@MNPs, 16.5+/-6.1 nm, positive charge) and magnetic nanoparticles agglomerates, formed by electronic aggregation between DMSA@MNPs and CS (CS-DMSA@MNPs, 85.7+/-72.9 nm, positive charge) respectively. The interactions of these MNPs with Oral Squamous Carcinoma Cell KB were investigated. The results showed that cellular uptakes of MNPs were on the dependence of incubation time, nanoparticles concentration and nanoparticles properties such as surface charge, size, etc. The cellular uptake was enhanced with the increase of incubation time and nanoparticles concentration. Although all MNPs could enter to cells, we observed apparent differences in the magnitude of nanoparticles uptaken. The cellular uptake of CS-DMSA@MNPs by KB cells was the highest and that of DMSA@MNPs was the lowest among the three types of MNPs. The same conclusions were drawn via the reduction of water proton relaxation times T(2)(*), resulting from the different iron load of labeled cells using a 1.5T clinical MR imager. The finding of this study will have implications in the chemical design of nanomaterials for biomedical applications.

  6. Evaluating the effect of ultrasmall superparamagnetic iron oxide nanoparticles for a long-term magnetic cell labeling

    Directory of Open Access Journals (Sweden)

    Saeed Shanehsazzadeh

    2013-01-01

    Full Text Available In order to evaluate the long-term viability, the iron content stability, and the labeling efficiency of mammalian cells using magnetic cell labeling; dextran-coated ultrasmall superparamagnetic iron oxide (USPIOs nanoparticles with plain surfaces having a hydrodynamic size of 25 nm were used for this study. Tests were carried out in four groups each containing 5 flasks of 5.5 × 10 6 AD-293 embryonic kidney cells. The cell lines were incubated for 24 h using four different iron concentrations with and without protamine sulfate (Pro, washed with phosphate-buffered saline (PBS and centrifuged three times to remove the unbounded USPIOs. Cell viability was also verified using USPIOs. There were no significant differences in the cell viability between the control group of cells and those groups with iron uptake at the specified iron concentrations. The average iron uptake ratio compared to that of the control group was (114 ± 1. The magnetic resonance images (MRI at post-labeling day 1 and day 21 showed (75 ± 4% and (22 ± 5% signal decrements compared to that of the control, respectively. The Perl′s Prussian blue test showed that 98% of the cells were labeled, and the iron concentration within the media did not affect the cell iron uptake. Magnetic cellular labeling with the USPIO-Pro complex had no short or medium term (3 weeks toxic effects on AD-293 embryonic kidney cells.

  7. Endoscopic ultrasound guided injection of iron oxide magnetic nanoparticles for liver and pancreas

    DEFF Research Database (Denmark)

    Ungureanu, Bogdan Silviu; Pirici, Daniel; Margaritescu, Claudiu

    2016-01-01

    AIMS: Pancreatic cancer and hepatocellular carcinoma are two of the most aggressive types of cancer with limited therapeutic options in stages of advanced disease. Our objective is to assess the safety and feasibility of injecting iron oxide nanoparticles (IONs) via endoscopic ultrasound (EUS......)-guidance, both systemically and locally in the liver and pancreas in order to study new potential therapies for liver and pancreatic tumors. MATERIAL AND METHODS: Six domestic pigs were used for our study design, and divided into three groups: two were injected in the portal vein, and other four were subjected...... to local exposure of IONs in the liver and pancreas, two each. The pigs were on a 7 days follow-up and necropsy was performed with their organs harvested. A 3T MRI scan was also performed. RESULTS: All animals underwent an endoscopic ultrasound fine needle injection (EUS-FNI) procedure without any...

  8. Albumin and Hyaluronic Acid-Coated Superparamagnetic Iron Oxide Nanoparticles Loaded with Paclitaxel for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Elena Vismara

    2017-06-01

    Full Text Available Super paramagnetic iron oxide nanoparticles (SPION were augmented by both hyaluronic acid (HA and bovine serum albumin (BSA, each covalently conjugated to dopamine (DA enabling their anchoring to the SPION. HA and BSA were found to simultaneously serve as stabilizing polymers of Fe3O4·DA-BSA/HA in water. Fe3O4·DA-BSA/HA efficiently entrapped and released the hydrophobic cytotoxic drug paclitaxel (PTX. The relative amount of HA and BSA modulates not only the total solubility but also the paramagnetic relaxation properties of the preparation. The entrapping of PTX did not influence the paramagnetic relaxation properties of Fe3O4·DA-BSA. Thus, by tuning the surface structure and loading, we can tune the theranostic properties of the system.

  9. Evaluation of iron-cobalt/ferrite core-shell nanoparticles for cancer thermotherapy

    Science.gov (United States)

    Habib, A. H.; Ondeck, C. L.; Chaudhary, P.; Bockstaller, M. R.; McHenry, M. E.

    2008-04-01

    Magnetic nanoparticles (MNPs) offer promise for local hyperthermia or thermoablative cancer therapy. Magnetic hyperthermia uses MNPs to heat cancerous regions in an rf field. Metallic MNPs have larger magnetic moments than iron oxides, allowing similar heating at lower concentrations. By tuning the magnetic anisotropy in alloys, the heating rate at a particular particle size can be optimized. Fe-Co core-shell MNPs have protective CoFe2O4 shell which prevents oxidation. The oxide coating also aids in functionalization and improves biocompatibility of the MNPs. We predict the specific loss power (SLP) for FeCo (SLP ˜450W /g) at biocompatible fields to be significantly larger in comparision to oxide materials. The anisotropy of Fe-Co MNPs may be tuned by composition and/or shape variation to achieve the maximum SLP at a desired particle size.

  10. Treatment of a suspension of PCB contaminated soil using iron nanoparticles and electric current

    DEFF Research Database (Denmark)

    Comes, Helena I.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2015-01-01

    Contaminated soils and sediments with polychlorinated biphenyls (PCB) are an important environmental problem due to the persistence of these synthetic aromatic compounds and to the lack of a cost-effective and sustainable remediation technology. Recently, a new experimental setup has been proposed...... using electrodialytic remediation and iron nanoparticles. The current work compares the performance of this new setup (A) with conventional electrokinetics (setup B). An historically contaminated soil with an initial PCB concentration of 258 mu g kg-1 was treated during 5, 10, 20 and 45 d using...... gradient when compared with the traditional setup (B). Energy and nZVI costs for a full-scale reactor are estimated at 72 (sic) for each cubic meter of PCB contaminated soil treated on-site, making this technology competitive when compared with average off-site incineration (885 (sic) m-3) or landfilling...

  11. Factors on the magnetic properties of the iron nanoparticles by classical Heisenberg model

    Science.gov (United States)

    Nguyen, Trong Dung; Nguyen, Chinh Cuong; Nguyen, The Toan; Pham, Khac Hung

    2018-03-01

    In this paper, we used the Monte-Carlo simulation technique to investigate the magnetic properties of the samples of amorphous iron material which could be described as a spin Heisenberg system. The exchange interaction is taken into account as a function of the distance between the two spins. The results showed the existence of the magnetic phase transition behavior of the nanoparticles. The phase transition temperature obtained by our simulations and the semi-empirical calculations are well matched. The magnetization of the core/shell system strongly depends on the shell thickness when the spins on the interface of the core and the shell layer are frustrated. The transition temperature seems to be independent on the structure of the shell.

  12. Removal of Reactive Red 198 by Nanoparticle Zero Valent Iron in the Presence of Hydrogen Peroxide

    Directory of Open Access Journals (Sweden)

    Siroos Shojaei

    2017-04-01

    Full Text Available Although dyes are widely used in textile industries, they are carcinogenic, teratogenic and mutagenic. Industries discharge their wastewater containing a variety of colors into water resources and make harmful effect on the environment. The present study aims to Evaluate removal of reactive red 198 by nanoparticle zero valent iron (NZVI in the presence of hydrogen peroxide from aqueous solution. The effective parameters on the removal of dye such as the hydrogen peroxide concentration of NZVI, contact time, pH and dye concentration were investigated and optimized. According to the results, the combination of NZVI with hydrogen peroxide is more effective than single hydrogen peroxide. At pH = 4, contact time= 40 min, 200 M of hydrogen peroxide, dye concentration= 75 mg/L and concentration of NZVI 2g/L, color removal was achieved 91% approximately. Based on the results of experiments, using hydrogen peroxide- NZVI has high efficiency in removal of azo dye type.

  13. Structural and magnetic properties of cobalt-doped iron oxide nanoparticles prepared by solution combustion method for biomedical applications

    Directory of Open Access Journals (Sweden)

    Venkatesan K

    2015-10-01

    Full Text Available Kaliyamoorthy Venkatesan,1 Dhanakotti Rajan Babu,1 Mane Prabhu Kavya Bai,2 Ravi Supriya,2 Radhakrishnan Vidya,2 Saminathan Madeswaran,1 Pandurangan Anandan,3 Mukannan Arivanandhan,3 Yasuhiro Hayakawa3 1School of Advanced Sciences, 2School of Bio Sciences and Technology, VIT University, Vellore, Tamil Nadu, India; 3Research Institute of Electronics, Shizuoka University, Hamamatsu, Japan Abstract: Cobalt-doped iron oxide nanoparticles were prepared by solution combustion technique. The structural and magnetic properties of the prepared samples were also investigated. The average crystallite size of cobalt ferrite (CoFe2O4 magnetic nanoparticle was calculated using Scherrer equation, and it was found to be 16±5 nm. The particle size was measured by transmission electron microscope. This value was found to match with the crystallite size calculated by Scherrer equation corresponding to the prominent intensity peak (311 of X-ray diffraction. The high-resolution transmission electron microscope image shows clear lattice fringes and high crystallinity of cobalt ferrite magnetic nanoparticles. The synthesized magnetic nanoparticles exhibited the saturation magnetization value of 47 emu/g and coercivity of 947 Oe. The anti-microbial activity of cobalt ferrite nanoparticles showed better results as an anti-bacterial agent. The affinity constant was determined for the nanoparticles, and the cytotoxicity studies were conducted for the cobalt ferrite nanoparticles at different concentrations and the results are discussed. Keywords: cytotoxicity, HR-TEM, magnetic nanoparticles, VSM 

  14. The coating makes the difference: acute effects of iron oxide nanoparticles on Daphnia magna.

    Science.gov (United States)

    Baumann, Jonas; Köser, Jan; Arndt, Darius; Filser, Juliane

    2014-06-15

    The surface of nanoparticles (NP) is often functionalized with a capping agent to increase their colloidal stability. Having a strong effect on the characteristics of NP, the coating might already determine the risk from NP to organisms and the environment. In this study identical iron oxide nanoparticles (IONP; Ø 5-6nm) were functionalized with four different coatings: ascorbate (ASC-IONP), citrate (CIT-IONP), dextran (DEX-IONP), and polyvinylpyrrolidone (PVP-IONP). Ascorbate and citrate stabilize NP via electrostatic repulsion whereas dextran and polyvinylpyrrolidone are steric stabilizers. All IONP were colloidally stable over several weeks. Their acute effects on neonates of the waterflea Daphnia magna were investigated over 96h. The highest immobilizing effect was found for ASC- and DEX-IONP. In the presence of neonates, both agglomerated or flocculated and adsorbed to the carapace and filtering apparatuses, inducing high immobilization. Lower immobilization was found for CIT-IONP. Their effect was hypothesized to partly originate from an increased release of dissolved iron and the ability to form reactive oxygen species (ROS). Furthermore, incomplete ecdysis occurred at high concentrations of ASC-, DEX-, and CIT-IONP. PVP-IONP did not induce any negative effect, although high quantities were visibly ingested by the daphnids. PVP-IONP had the highest colloidal stability without any occurring agglomeration, adsorption, or dissolution. Only strong swelling of the PVP coating was observed in medium, highly increasing the hydrodynamic diameter. Each coating caused individual effects. Toxicity cannot be correlated to hydrodynamic diameter or the kind of stabilizing forces. Effects are rather linked to decreasing colloidal stability, the release of ions from the core material or the ability to form ROS, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Disturbance of ion environment and immune regulation following biodistribution of magnetic iron oxide nanoparticles injected intravenously.

    Science.gov (United States)

    Park, Eun-Jung; Kim, Sang-Wook; Yoon, Cheolho; Kim, Younghun; Kim, Jong Sung

    2016-01-22

    Although it is expected that accumulation of metal oxide nanoparticles that can induce redox reaction in the biological system may influence ion homeostasis and immune regulation through generation of free radicals, the relationship is still unclear. In this study, mice received magnetic iron oxide nanoparticles (M-FeNPs, 2 and 4 mg/kg) a single via the tail vein, and their distribution in tissues was investigated over time (1, 4, and 13 weeks). In addition, we evaluated the effects on homeostasis of redox reaction-related elements, the ion environment and immune regulation. The iron level in tissues reached at the maximum on 4 weeks after injection and M-FeNPs the most distributed in the spleen at 13 weeks. Additionally, levels of redox reaction-related elements in tissues were notably altered since 1 week post-injection. While levels of K(+) and Na(+) in tissue tended to decrease with time, Ca(2+) levels reached to the maximum at 4 weeks post-injection. On 13 weeks post-injection, the increased percentages of neutrophils and eosinophils, the enhanced release of LDH, and the elevated secretion of IL-8 and IL-6 were clearly observed in the blood of M-FeNP-treated mice compared to the control. While expression of antigen presentation related-proteins and the maturation of dendritic cells were markedly inhibited following distribution of M-FeNPs, the expression of several chemokines, including CXCR2, CCR5, and CD123, was enhanced on the splenocytes of the treated groups. Taken together, we suggest that accumulation of M-FeNPs may induce adverse health effects by disturbing homeostasis of the immune regulation and ion environment. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Magnetomotive imaging of iron oxide nanoparticles as cellular contrast agents for optical coherence tomography

    Science.gov (United States)

    Cimalla, Peter; Werner, Theresa; Gaertner, Maria; Mueller, Claudia; Walther, Julia; Wittig, Dierk; Ader, Marius; Karl, Mike; Koch, Edmund

    2013-06-01

    Recent studies in animal models provided proof-of-principle evidence for cell transplantation as a potential future therapeutic approach for retinal pathologies in humans such as Retinitis pigmentosa or age-related macular degeneration. In this case, donor cells are injected into the eye in order to protect or replace degenerating photoreceptors or retinal pigment epithelium. However, currently there is no three-dimensional imaging technique available that allows tracking of cell migration and integration into the host tissue under in vivo conditions. Therefore, we investigate about magnetomotive optical coherence tomography (OCT) of substances labeled with iron oxide nanoparticles as a potential method for noninvasive, three-dimensional cell tracking in the retina. We use a self-developed spectral domain OCT system for high-resolution imaging in the 800 nm-wavelength region. A suitable AC magnetic field for magnetomotive imaging was generated using two different setups, which consist of an electrically driven solenoid in combination with a permanent magnet, and a mechanically driven all-permanent magnet configuration. In the sample region the maximum magnetic flux density was 100 mT for both setups, with a field gradient of 9 T/m and 13 T/m for the solenoid and the allpermanent magnet setup, respectively. Magnetomotive OCT imaging was performed in elastic tissue phantoms and single cells labeled with iron oxide nanoparticles. Particle-induced sub-resolution movement of the elastic samples and the single cells could successfully be detected and visualized by means of phase-resolved Doppler OCT analysis. Therefore, this method is a potential technique to enhance image contrast of specific cells in OCT.

  17. Superparamagnetic iron oxide nanoparticles for delivery of therapeutic agents: opportunities and challenges.

    Science.gov (United States)

    Laurent, Sophie; Saei, Amir Ata; Behzadi, Shahed; Panahifar, Arash; Mahmoudi, Morteza

    2014-09-01

    Bearing in mind that many promising drug candidates have the problem of reaching their target site, the concept of advanced drug delivery can play a significant complementary role in shaping modern medicine. Among other nanoscale drug carriers, superparamagnetic iron oxide nanoparticles (SPIONs) have shown great potential in nanomedicine. The intrinsic properties of SPIONs, such as inherent magnetism, broad safety margin and the availability of methods for fabrication and surface engineering, pave the way for diverse biomedical applications. SPIONs can achieve the highest drug targeting efficiency among carriers, since an external magnetic field locally applied to the target organ enhances the accumulation of magnetic nanoparticles in the drug site of action. Moreover, theranostic multifunctional SPIONs make simultaneous delivery and imaging possible. In spite of these favorable qualities, there are some toxicological concerns, such as oxidative stress, unpredictable cellular responses and induction of signaling pathways, alteration in gene expression profiles and potential disturbance in iron homeostasis, that need to be carefully considered. Besides, the protein corona at the surface of the SPIONs may induce few shortcomings such as reduction of SPIONs targeting efficacy. In this review, we will present recent developments of SPIONs as theranostic agents. The article will further address some barriers on drug delivery using SPIONs. One of the major success determinants in targeted in vivo drug delivery using SPIONs is the adequacy of magnetic gradient. This can be partially achieved by using superconducting magnets, local implantation of magnets and application of magnetic stents. Other issues that must be considered include the pharmacokinetics and in vivo fate of SPIONs, their biodegradability, biocompatibility, potential side effects and the crucial impact of protein corona on either drug release profile or mistargeting. Surface modification of SPIONs can open

  18. Impact of Amino-Acid Coating on the Synthesis and Characteristics of Iron-Oxide Nanoparticles (IONs)

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahiminezhad, Alireza; Barar, Jaleh; Davaran, Soodabeh [Tabriz Univ. of Medical Sciences, Tabriz (Iran, Islamic Republic of); Ghasemi, Younes; Sara, Rasoulamini [Shiraz Univ. of Medical Sciences, Shiraz (Iran, Islamic Republic of)

    2012-12-15

    Iron-oxide nanoparticles (IONs) with biocompatible coatings are the only nanostructural materials which have been approved by the FDA for clinical use. Common biocompatible coatings such as hydrocarbons, polymers, and silica have profound influences on critical characteristics of IONs. Recently, amino acids were introduced as a novel biocompatible coating. In the present study, the effects of amino acids on IONs synthesis and characteristics have been evaluated. Magnetite nanoparticles with {sub L}-arginine and {sub L}-lysine coatings were synthesised by a coprecipitation reaction in aqueous solvent and their characteristics were compared with naked magnetite nanoparticles. The results showed that amino acids can be a perfect coating for IONs and would increase particle stability without any significant effects on the critical properties of nanoparticles such as particle size and magnetization saturation value.

  19. The distribution and degradation of radiolabeled superparamagnetic iron oxide nanoparticles and quantum dots in mice

    Directory of Open Access Journals (Sweden)

    Denise Bargheer

    2015-01-01

    Full Text Available 51Cr-labeled, superparamagnetic, iron oxide nanoparticles (51Cr-SPIOs and 65Zn-labeled CdSe/CdS/ZnS-quantum dots (65Zn-Qdots were prepared using an easy, on demand, exchange-labeling technique and their particokinetic parameters were studied in mice after intravenous injection. The results indicate that the application of these heterologous isotopes can be used to successfully mark the nanoparticles during initial distribution and organ uptake, although the 65Zn-label appeared not to be fully stable. As the degradation of the nanoparticles takes place, the individual transport mechanisms for the different isotopes must be carefully taken into account. Although this variation in transport paths can bring new insights with regard to the respective trace element homeostasis, it can also limit the relevance of such trace material-based approaches in nanobioscience. By monitoring 51Cr-SPIOs after oral gavage, the gastrointestinal non-absorption of intact SPIOs in a hydrophilic or lipophilic surrounding was measured in mice with such high sensitivity for the first time. After intravenous injection, polymer-coated, 65Zn-Qdots were mainly taken up by the liver and spleen, which was different from that of ionic 65ZnCl2. Following the label for 4 weeks, an indication of substantial degradation of the nanoparticles and the release of the label into the Zn pool was observed. Confocal microscopy of rat liver cryosections (prepared 2 h after intravenous injection of polymer-coated Qdots revealed a colocalization with markers for Kupffer cells and liver sinusoidal endothelial cells (LSEC, but not with hepatocytes. In J774 macrophages, fluorescent Qdots were found colocalized with lysosomal markers. After 24 h, no signs of degradation could be detected. However, after 12 weeks, no fluorescent nanoparticles could be detected in the liver cryosections, which would confirm our 65Zn data showing a substantial degradation of the polymer-coated CdSe/CdS/ZnS-Qdots in

  20. Adherence of amino acids functionalized iron oxide nanoparticles on bacterial models E. Coli and B. subtilis

    Science.gov (United States)

    Trujillo, W.; Zarria, J.; Pino, J.; Menacho, L.; Coca, M.; Bustamante, A.

    2018-03-01

    Magnetic iron oxides nanoparticles (NPs) functionalized with lysine (Lys) and arginine (Arg) was obtained by following chemical co-precipitation route in basic medium. The synthesis was performed by mixing ferrous chloride (FeCl2•4H2O), ferric chloride (FeCl3•6H2O) and the specific amino acid in a molar ratio of 1: 2: 0.5, respectively. High pH sample was washed several times with distilled water to reach a pH similar to distilled water (Ph=7) after the synthesis process, part of the NPs obtained was dried. Of the measurements of XRD and MS was obtained that the samples are magnetic nanoparticles of maghemite of about 9 nm in diameter. Of the FTIR and zeta potential measures was obtained that the amino acids Lys and Arg were correctly functionalized at magnetic nanoparticles, referred to herein as M@Lys and M@Arg. In order to demonstrate the capture and adhesion of the nanoparticles to the bacteria, scanning electron microscopy (SEM) was performed. The obtained visualization of both bacteria shows that they are coated by the magnetic particles. In addition, M@Lys (B. sutilis) were cultured to verify the inhibition of growth measured by colony forming units (CFU), the concentrations of M@Lys were 1.75x102 g/mL and 0.875x102 g/mL. After the confrontation obtained efficiencies of 75.63% and 98.75% respectively for the third dilution. While for the fourth dilution were 90% and 98.57% respectively were obtained for each concentration of nanoparticles. Hinting that a high efficiency of bacterial capture at very low concentrations of NPs, which gives us a tool to capture nanobiotechnology bacteria in liquid cultures with application to capture them in wastewater. Based on our results we concluded that NPS functionalized with the amino acids Lys and Arg adhere to the bacteria efficiently in low concentrations.

  1. Enhanced MRI T 2 Relaxivity in Contrast-Probed Anchor-Free PEGylated Iron Oxide Nanoparticles

    Science.gov (United States)

    Thapa, Bibek; Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Weiner, Brad R.; Morell, Gerardo

    2017-04-01

    Superparamagnetic iron oxide nanoparticles (SPIONs, 11-nm cores) were PEGylated without anchoring groups and studied as efficient MRI T 2 contrast agents (CAs). The ether group of PEG is efficiently and directly linked to the positively charged surface of SPIONs, and mediated through a dipole-cation covalent interaction. Anchor-free PEG-SPIONs exhibit a spin-spin relaxivity of 123 ± 6 mM-1s-1, which is higher than those of PEG-SPIONs anchored with intermediate biomolecules, iron oxide nanoworms, or Feridex. They do not induce a toxic response for Fe concentrations below 2.5 mM, as tested on four different cell lines with and without an external magnetic field. Magnetic resonance phantom imaging studies show that anchor-free PEG-SPIONs produce a significant contrast in the range of 0.1-0.4 [Fe] mM. Our findings reveal that the PEG molecules attached to the cores immobilize water molecules in large regions of 85 nm, which would lead to blood half-life of a few tens of minutes. This piece of research represents a step forward in the development of next-generation CAs for nascent-stage cancer detection.

  2. Green synthesis of iron nanoparticles by various tea extracts: Comparative study of the reactivity

    Science.gov (United States)

    Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-09-01

    Iron nanoparticles (Fe NPs) are often synthesized using sodium borohydride with aggregation, which is a high cost process and environmentally toxic. To address these issues, Fe NPs were synthesized using green methods based on tea extracts, including green, oolong and black teas. The best method for degrading malachite green (MG) was Fe NPs synthesized by green tea extracts because it contains a high concentration of caffeine/polyphenols which act as both reducing and capping agents in the synthesis of Fe NPs. These characteristics were confirmed by a scanning electron microscope (SEM), UV-visible (UV-vis) and specific surface area (BET). To understand the formation of Fe NPs using various tea extracts, the synthesized Fe NPs were characterized by SEM, X-ray energy-dispersive spectrometer (EDS), and X-ray diffraction (XRD). What emerged were different sizes and concentrations of Fe NPs being synthesized by tea extracts, leading to various degradations of MG. Furthermore, kinetics for the degradation of MG using these Fe NPs fitted well to the pseudo first-order reaction kinetics model with more than 20 kJ/mol activation energy, suggesting a chemically diffusion-controlled reaction. The degradation mechanism using these Fe NPs included adsorption of MG to Fe NPs, oxidation of iron, and cleaving the bond that was connected to the benzene ring.

  3. Watermelon-like iron nanoparticles: Cr doping effect on magnetism and magnetization interaction reversal

    Science.gov (United States)

    Kaur, Maninder; Dai, Qilin; Bowden, Mark; Engelhard, Mark H.; Wu, Yaqiao; Tang, Jinke; Qiang, You

    2013-08-01

    Cr-doped core-shell iron/iron-oxide nanoparticles (NPs) containing 0, 2, 5, and 8 at.% of Cr dopant were synthesized via a nanocluster deposition system and their structural and magnetic properties were investigated. We observed the formation of a σ-FeCr phase in 2 at.% of Cr doping in core-shell NPs. This is unique since it was reported in the past that the σ-phase forms above 20 at.% of Cr. The large coercive field and exchange bias are ascribed to the antiferromagnetic Cr2O3 layer formed with the Fe-oxide shell, which also acts as a passivation layer to decrease the Fe-oxide shell thickness. The additional σ-phase in the core and/or Cr2O3 in the shell cause the hysteresis loop to appear tight waisted near the zero-field axis. The exchange interaction competes with the dipolar interaction with the increase of σ-FeCr grains in the Fe-core. The interaction reversal has been observed in 8 at.% of Cr. The observed reversal mechanism is confirmed from the Henkel plot and delta M value, and is supported by a theoretical watermelon model based on the core-shell nanostructure system.

  4. Zero-valent iron nanoparticles in treatment of acid mine water from in situ uranium leaching.

    Science.gov (United States)

    Klimkova, Stepanka; Cernik, Miroslav; Lacinova, Lenka; Filip, Jan; Jancik, Dalibor; Zboril, Radek

    2011-02-01

    Acid mine water from in situ chemical leaching of uranium (Straz pod Ralskem, Czech Republic) was treated in laboratory scale experiments by zero-valent iron nanoparticles (nZVI). For the first time, nZVI were applied for the treatment of the real acid water system containing the miscellaneous mixture of pollutants, where the various removal mechanisms occur simultaneously. Toxicity of the treated saline acid water is caused by major contaminants represented by aluminum and sulphates in a high concentration, as well as by microcontaminants like As, Be, Cd, Cr, Cu, Ni, U, V, and Zn. Laboratory batch experiments proved a significant decrease in concentrations of all the monitored pollutants due to an increase in pH and a decrease in oxidation-reduction potential related to an application of nZVI. The assumed mechanisms of contaminants removal include precipitation of cations in a lower oxidation state, precipitation caused by a simple pH increase and co-precipitation with the formed iron oxyhydroxides. The possibility to control the reaction kinetics through the nature of the surface stabilizing shell (polymer vs. FeO nanolayer) is discussed as an important practical aspect. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Polyelectrolyte multilayer film-assisted formation of zero-valent iron nanoparticles onto polymer nanofibrous mats

    International Nuclear Information System (INIS)

    Xiao Shili; Shi Xiangyang; Wu Siqi; Shen Mingwu; Guo Rui; Wang Shanyuan

    2009-01-01

    A facile approach that combines the electrospinning technique and layer-by-layer (LbL) assembly method has been developed to synthesize and immobilize zero-valent iron nanoparticles (ZVI NPs) onto the surface of nanofibers for potential environmental applications. In this approach, negatively charged cellulose acetate (CA) nanofibers fabricated by electrospinning CA solution were modified with bilayers composed of positively charged poly(diallyl-dimethyl-ammoniumchloride) (PDADMAC) and negatively charged poly(acrylic acid) (PAA) through electrostatic LbL assembly approach to form composite nanofibrous mats. The composite nanofibrous mats were immersed into the ferrous iron solution to allow Fe(II) ions to complex with the free carboxyl groups of PAA, and then ZVI NPs were immobilized onto the composite nanofibrous mats instantly by reducing the ferrous cations. Combined scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and thermogravimetry analysis demonstrated that the ZVI NPs are successfully synthesized and uniformly distributed into the polyelectrolyte (PE) multilayer films assembled onto the CA nanofibers. The present approach to synthesis ZVI NPs opens a new avenue to fabricating various materials with high surface area for environmental, catalytic, and sensing applications.

  6. Assessment of Morphological and Functional Changes in Organs of Rats after Intramuscular Introduction of Iron Nanoparticles and Their Agglomerates

    Directory of Open Access Journals (Sweden)

    Elena Sizova

    2015-01-01

    Full Text Available The research was performed on male Wistar rats based on assumptions that new microelement preparations containing metal nanoparticles and their agglomerates had potential. Morphological and functional changes in tissues in the injection site and dynamics of chemical element metabolism (25 indicators in body were assessed after repeated intramuscular injections (total, 7 with preparation containing agglomerate of iron nanoparticles. As a result, iron depot was formed in myosymplasts of injection sites. The quantity of muscle fibers having positive Perls’ stain increased with increasing number of injections. However, the concentration of the most chemical elements and iron significantly decreased in the whole skeletal muscle system (injection sites are not included. Consequently, it increased up to the control level after the sixth and the seventh injections. Among the studied organs (liver, kidneys, and spleen, Caspase-3 expression was revealed only in spleen. The expression had a direct dependence on the number of injections. Processes of iron elimination from preparation containing nanoparticles and their agglomerates had different intensity.

  7. Experimental Investigation of the Magnetorheological Behavior of PDMS Elastomer Reinforced with Iron Micro/Nanoparticles

    Directory of Open Access Journals (Sweden)

    Luis Manuel Palacios-Pineda

    2017-12-01

    Full Text Available The aim of this article focuses on identifying how the addition of iron micro- and nanoparticles influences the physical properties of magnetorheological composite materials developed with a polydimethylsiloxane (PDMS matrix with different contents of silicone oil used as additive. A number of characterization techniques have been performed in order to fully characterize the samples, such as cyclic and uniaxial extension, rheology, swelling, Vibrating sample magnetometer (VSM, X-ray Diffraction (XRD, Scanning electron microscopy (SEM, Fourier-Transform Infrared (FTIR, X-ray photoelectronic spectroscopy (XPS and Thermogravimetric analysis (TGA. The comparison between two matrices with different shore hardnesses and their mechanical and chemical properties are elucidated by swelling and tensile tests. In fact, swelling tests showed that higher crosslink density leads to increasing elongation at break and tensile strength values for the composite materials. The best mechanical performance in the magnetorheological material was observed for those samples manufactured using a higher silicone oil content in a hard polymeric matrix. Furthermore, it has been found that the magnetic properties are enhanced when nanoparticles are used as fillers instead of microparticles.

  8. Polyelectrolyte coating on superparamagnetic iron oxide nanoparticles as interface between magnetic core and biorelevant media.

    Science.gov (United States)

    Tombácz, Etelka; Farkas, Katalin; Földesi, Imre; Szekeres, Márta; Illés, Erzsébet; Tóth, Ildikó Y; Nesztor, Daniel; Szabó, Tamás

    2016-12-06

    Nanoparticles do not exist in thermodynamical equilibrium because of high surface free energy, thus they have only kinetic stability. Spontaneous changes can be delayed by designed surface coating. In biomedical applications, superparamagnetic iron oxide nanoparticles (SPIONs) require an optimized coating in order to fulfil the expectation of medicine regulatory agencies and ultimately that of biocompatibility. In this work, we show the high surface reactivity of naked SPIONs due to ≡Fe-OH sites, which can react with H + /OH - to form pH- and ionic strength-dependent charges. We explain the post-coating of naked SPIONs with organic polyacids via multi-site complex bonds formed spontaneously. The excess polyacids can be removed from the medium. The free COOH groups in coating are prone to react with active biomolecules like proteins. Charging and pH- and salt-dependent behaviour of carboxylated SPIONs were characterized quantitatively. The interrelation between the coating quality and colloidal stability measured under biorelevant conditions is discussed. Our coagulation kinetics results allow us to predict colloidal stability both on storage and in use; however, a simpler method would be required to test SPION preparations. Haemocompatibility tests (smears) support our qualification for good and bad SPION manufacturing; the latter 'promises' fatal outcome in vivo .

  9. Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Bloemen, Maarten, E-mail: maarten.bloemen@fys.kuleuven.be; Brullot, Ward; Luong, Tai Thien [KU Leuven, Department of Chemistry (Belgium); Geukens, Nick [KU Leuven, PharmAbs, The KU Leuven Antibody Center (Belgium); Gils, Ann [KU Leuven, Faculty of Pharmaceutical Sciences (Belgium); Verbiest, Thierry [KU Leuven, Department of Chemistry (Belgium)

    2012-09-15

    Superparamagnetic iron oxide nanoparticles can provide multiple benefits for biomedical applications in aqueous environments such as magnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles' surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality water-dispersible nanoparticles around 10 nm in size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.

  10. Polymer encapsulated upconversion nanoparticle/iron oxide nanocomposites for multimodal imaging and magnetic targeted drug delivery.

    Science.gov (United States)

    Xu, Huan; Cheng, Liang; Wang, Chao; Ma, Xinxing; Li, Yonggang; Liu, Zhuang

    2011-12-01

    Multimodal imaging and imaging-guided therapies have become a new trend in the current development of cancer theranostics. In this work, we encapsulate hydrophobic upconversion nanoparticles (UCNPs) together with iron oxide nanoparticles (IONPs) by using an amphiphilic block copolymer, poly (styrene-block-allyl alcohol) (PS(16)-b-PAA(10)), via a microemulsion method, obtaining an UC-IO@Polymer multi-functional nanocomposite system. Fluorescent dye and anti-cancer drug molecules can be further loaded inside the UC-IO@Polymer nanocomposite for additional functionalities. Utilizing the Squaraine (SQ) dye loaded nanocomposite (UC-IO@Polymer-SQ), triple-modal upconversion luminescence (UCL)/down-conversion fluorescence (FL)/magnetic resonance (MR) imaging is demonstrated in vitro and in vivo, and also applied for in vivo cancer cell tracking in mice. On the other hand, a chemotherapy drug, doxorubicin, is also loaded into the nanocomposite, forming an UC-IO@Polymer-DOX complex, which enables novel imaging-guided and magnetic targeted drug delivery. Our work provides a method to fabricate a nanocomposite system with highly integrated functionalities for multimodal biomedical imaging and cancer therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Superparamagnetic Iron Oxide Nanoparticles Coated with Galactose-Carrying Polymer for Hepatocyte Targeting

    Directory of Open Access Journals (Sweden)

    Mi Kyong Yoo

    2007-01-01

    Full Text Available Our goal is to develop the functionalized superparamagnetic iron oxide nanoparticles (SPIONs demonstrating the capacities to be delivered in liver specifically and to be dispersed in physiological environment stably. For this purpose, SPIONs were coated with polyvinylbenzyl-O-β-D-galactopyranosyl-D-gluconamide (PVLA having galactose moieties to be recognized by asialoglycoprotein receptors (ASGP-R on hepatocytes. For use as a control, we also prepared SPIONs coordinated with 2-pyrrolidone. The sizes, size distribution, structure, and coating of the nanoparticles were characterized by transmission electron microscopy (TEM, electrophoretic light scattering spectrophotometer (ELS, X-ray diffractometer (XRD, and Fourier transform infrared (FT-IR, respectively. Intracellular uptake of the PVLA-coated SPIONs was visualized by confocal laser scanning microscopy, and their hepatocyte-specific delivery was also investigated through magnetic resonance (MR images of rat liver. MRI experimental results indicated that the PVLA-coated SPIONs possess the more specific accumulation property in liver compared with control, which suggests their potential utility as liver-targeting MRI contrast agent.

  12. Dual drug loaded superparamagnetic iron oxide nanoparticles for targeted cancer therapy.

    Science.gov (United States)

    Dilnawaz, Fahima; Singh, Abhalaxmi; Mohanty, Chandana; Sahoo, Sanjeeb K

    2010-05-01

    The primary inadequacy of chemotherapeutic drugs is their relative non-specificity and potential side effects to the healthy tissues. To overcome this, drug loaded multifunctional magnetic nanoparticles are conceptualized. We report here an aqueous based formulation of glycerol monooleate coated magnetic nanoparticles (GMO-MNPs) devoid of any surfactant capable of carrying high payload hydrophobic anticancer drugs. The biocompatibility was confirmed by tumor necrosis factor alpha assay, confocal microscopy. High entrapment efficiency approximately 95% and sustained release of encapsulated drugs for more than two weeks under in vitro conditions was achieved for different anticancer drugs (paclitaxel, rapamycin, alone or combination). Drug loaded GMO-MNPs did not affect the magnetization properties of the iron oxide core as confirmed by magnetization study. Additionally the MNPs were functionalized with carboxylic groups by coating with DMSA (Dimercaptosuccinic acid) for the supplementary conjugation of amines. For targeted therapy, HER2 antibody was conjugated to GMO-MNPs and showed enhanced uptake in human breast carcinoma cell line (MCF-7). The IC(50) doses revealed potential antiproliferative effect in MCF-7. Therefore, antibody conjugated GMO-MNPs could be used as potential drug carrier for the active therapeutic aspects in cancer therapy. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. Size-controlled synthesis of dextran sulfate coated iron oxide nanoparticles for magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jarrett, Benjamin R; Frendo, Michele; Vogan, Jacob; Louie, Angelique Y [Department of Biomedical Engineering, University of California, Davis, CA 95616 (United States)

    2007-01-24

    In the generation of nanoparticles for biological applications, the control over synthetic parameters influencing the particles' physicochemical properties are of great interest due to the strong influence of particle size and surface properties on cellular uptake and biodistribution. We have synthesized dextran sulfate coated particles and systematically evaluated synthetic parameters that may influence the properties of these nanoparticles as potential magnetic resonance (MR) contrast agents. The amount of base, polysaccharide content, ratio of iron salts, and reaction time were optimized to yield approximately 30 nm particles as determined by dynamic light scattering with good MR properties (r{sub 1} = 14.46 mM{sup -1} s{sup -1} and r{sub 2} = 72.55 mM{sup -1} s{sup -1}) and in good yield (50%). Particle sizes and relaxivities are compared with clinically available dextran coated particles and the resulting physical properties of the dextran sulfate coated particles show these particles could be used as potential MR contrast agents for cardiovascular imaging.

  14. Tailored functionalization of iron oxide nanoparticles for MRI, drug delivery, magnetic separation and immobilization of biosubstances.

    Science.gov (United States)

    Hola, Katerina; Markova, Zdenka; Zoppellaro, Giorgio; Tucek, Jiri; Zboril, Radek

    2015-11-01

    In this critical review, we outline various covalent and non-covalent approaches for the functionalization of iron oxide nanoparticles (IONPs). Tuning the surface chemistry and design of magnetic nanoparticles are described in relation to their applicability in advanced medical technologies and biotechnologies including magnetic resonance imaging (MRI) contrast agents, targeted drug delivery, magnetic separations and immobilizations of proteins, enzymes, antibodies, targeting agents and other biosubstances. We review synthetic strategies for the controlled preparation of IONPs modified with frequently used functional groups including amine, carboxyl and hydroxyl groups as well as the preparation of IONPs functionalized with other species, e.g., epoxy, thiol, alkane, azide, and alkyne groups. Three main coupling strategies for linking IONPs with active agents are presented: (i) chemical modification of amine groups on the surface of IONPs, (ii) chemical modification of bioactive substances (e.g. with fluorescent dyes), and (iii) the activation of carboxyl groups mainly for enzyme immobilization. Applications for drug delivery using click chemistry linking or biodegradable bonds are compared to non-covalent methods based on polymer modified condensed magnetic nanoclusters. Among many challenges, we highlight the specific surface engineering allowing both therapeutic and diagnostic applications (theranostics) of IONPs and magnetic/metallic hybrid nanostructures possessing a huge potential in biocatalysis, green chemistry, magnetic bioseparations and bioimaging. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy.

    Science.gov (United States)

    Yang, Rui-Meng; Fu, Chao-Ping; Fang, Jin-Zhi; Xu, Xiang-Dong; Wei, Xin-Hua; Tang, Wen-Jie; Jiang, Xin-Qing; Zhang, Li-Ming

    2017-01-01

    Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA)-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs), which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhan