scholarly journals Superparamagnetic Iron Oxide (Fe3O4) Nanoparticles Coated with PEG/PEI for Biomedical Applications: A Facile and Scalable Preparation Route Based on the Cathodic Electrochemical Deposition Method

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Isa Karimzadeh ◽  
Mustafa Aghazadeh ◽  
Taher Doroudi ◽  
Mohammad Reza Ganjali ◽  
Peir Hossein Kolivand
Keyword(s):  
Iron Oxide ◽  
Electrochemical Deposition ◽  
Biomedical Applications ◽  
Superparamagnetic Iron Oxide ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrochemical Deposition Method ◽  
Preparation Route ◽  
Magnetite Phase

Cathodic electrochemical deposition (CED) is introduced as an efficient and effective method for synthesis and surface coating of superparamagnetic iron oxide nanoparticles (SPIONs). In this way, bare Fe3O4 nanoparticles were electrosynthesized through CED method from aqueous solution Fe3+ : Fe2+ chloride (molar ratio of 2 : 1). In the next step, the surface of NPs was coated with polyethyleneimine (PEI) and polyethylene glycol (PEG) during the CED procedure, and PEG/PEI coated SPIONs were obtained. The prepared NPs were evaluated by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering (DLS), vibrating sample magnetometer (VSM), and field-emission scanning electron microscopy (FE-SEM). The pure magnetite phase and nanosize (about 15 nm) of the prepared NPs were confirmed by XRD and FE-SEM. The presence of two coats (i.e., PEG and PEI) on the surface of electrosynthesized NPs was proved via FTIR results. The percentage of polymer coat (37.5%) on the NPs surface was provided by TGA analysis. The high magnetization value, negligible coercivity, and remanence measured by VSM indicate the superparamagnetic nature of both prepared NPs. The obtained results confirmed that the prepared Fe3O4 nanoparticles have suitable physicochemical and magnetic properties for biomedical applications.

Physicochemical properties of chitosan–magnetite nanocomposites obtained with different pH

2021 ◽  
pp. 096739112110384
Author(s):  
Christian Chapa González ◽  
Javier Ulises Navarro Arriaga ◽  
Perla Elvia García Casillas
Keyword(s):  
Zeta Potential ◽  
Physicochemical Properties ◽  
Biomedical Applications ◽  
Spherical Shape ◽  
Polymeric Coating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coated Nanoparticles ◽  
Nanoparticle Surface ◽  
Magnetite Phase

The physicochemical properties of the nanoparticle surface determine the performance of nanocomposites in biomedical applications such as their biodistribution and pharmacokinetics. The physicochemical properties of chitosan, such as apparent charge density and solubility, are pH dependent. Similarly, Fe3O4 nanoparticles are susceptible to variations in their physicochemical properties due to changes in pH. In this work, we evaluated the physicochemical properties of chitosan–magnetite nanocomposites that were suspended at pH 7.0, 9.0, and 11.0 to determinate the effect on particle size, zeta potential, and mass percentage of the polymeric coating, in addition to the crystalline phase and magnetic properties of magnetite phase. X-ray diffraction results exposed that the present phase was magnetite with no other phases present and that the crystallite size was between 10.8 and 14.1 nm. Fourier transform infrared verified the chitosan functional groups in treated samples while the percentage of mass determined by TGA found to be nearly 9%. Scanning electron microscopy micrographs corroborated the spherical shape of the bare and chitosan-coated nanoparticles. Dynamic light scattering results showed that chitosan coating modifies the zeta potential, going from a potential of −11.8 mV for bare particles to −3.0 mV (pH 11). Besides, vibrating sample magnetometer measurements showed that coercivity remained very low, which is desirable in biomedical applications.

Synthesis and Effect of Some Parameters through Reverse Micelles Route of Iron Oxide Nanoparticles

2009 ◽  
Vol 152-153 ◽  
pp. 205-208 ◽  
Author(s):  
H. Arabi ◽  
S. Nateghi ◽  
S. Sadeghi
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Reverse Micelles ◽  
Room Temperature ◽  
Molar Ratio ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Significant Difference ◽  
Vibration Sample Magnetometer

Iron oxide nanoparticles were synthesis by reverse micelle method. X-ray diffraction technique and vibration sample magnetometer were applied to characterize the produced samples at different conditions and parameters for synthesis route. There is no significant difference between samples prepared at 5°C and room temperature except a better crystalline at room temperature. The molar ratio of water to surfactant (w parameter) and concentration of the salt solution on size and magnetic properties of nanoparticles have been investigated. Increasing w leads to producing particles with larger size i.e. for w=16.83, 11.22, and 5.6, particles size are 15.22, 11.66 and 10.5 nm, respectively. The size of nanoparticles are in the range of 9 to 20 nanometers

scholarly journals Synthesis and Characterization of SPIONs for Biomedical applications

2014 ◽  
Vol 70 (a1) ◽  
pp. C743-C743
Author(s):  
Tatiane Britos ◽  
Li Min ◽  
Lilia De Souza Li ◽  
Paula Haddad
Keyword(s):  
Biomedical Applications ◽  
Superparamagnetic Iron Oxide ◽  
Cell Types ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mercaptosuccinic Acid ◽  
Transmission Electron ◽  
Oxidized Iron

This work reports the synthesis and characterization of superparamagnetic iron oxide nanoparticles (SPIONs), with great potential for biomedical applications. SPIONs were prepared through a decomposition of Fe(acac)3 in the presence of 1,2 hexadecanodiol (reducing agent), oleic acid and oleylamine (ligands) in a hot organic solvent. The mercaptosuccinic acid (MSA) and 2,3- dimercaptosuccinic acid (DMSA) were exchanged onto the nanocrystal surface making the particles stable in water. The thiolated nanoparticles (SH-NPs) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM). The as-prepared sample presented an amorphous partially oxidized iron structure. The results showed that the SH-NPs have a mean diameter of 6 nm and display superparamagnetic behavior at room temperature. Preliminary tests of incorporation of these systems were evaluated in Hela cells and stem cells. The results showed that the thiolated nanoparticles have no toxic effects for both cell types with good incorporation after 6 hours of transfection. Magnetic resonance image (MRI) were also carried and showed that the MNPs increase the contrast in systems investigated. Acknowledgements: FAPESP (2011/10125-0), CNPq, CAPES, UNICAMP

scholarly journals Enhancement of ZnO nanostructures Properties Grown by Electrochemical deposition technique

2019 ◽  
Vol 24 (7) ◽  
pp. 89
Author(s):  
Shahad A.D ◽  
N.K. Hassan ◽  
Q.H. Mahmood
Keyword(s):  
Electrochemical Deposition ◽  
Electromagnetic Spectrum ◽  
Zno Nanostructures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanostructure ◽  
Optical Gap ◽  
Electrochemical Deposition Method ◽  
20 Nm ◽  
Very High

ZnO nanostructure has been successfully synthesized on n-type Si (111) by electrochemical deposition method. The (FESEM) Images Showed that the Seed-shaped ZnO nanostructures with 20 nm radius occurred by changing the annealing time. The x-ray diffraction (XRD) revealed that ZnO were hexagonal grown with very high (101) orientation. The Optical gap spectrum proves that the grown ZnO Seed-shaped nanostructures of a very high quality in the UV region from electromagnetic spectrum.   http://dx.doi.org/10.25130/tjps.24.2019.133

Effect of Hydrated Metal Salts on the Coordination Product of Cobalt(II) halide and PNP Type Ligand, 2,6-bis(di-tertbutylphosphinomethyl) pyridine

2018 ◽  
Author(s):  
Tasneem Siddiquee ◽  
Abdul Goni
Keyword(s):  
Metal Salts ◽  
Molar Ratio ◽  
Pincer Complexes ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Pincer Ligand ◽  
Tetrahedral Geometry ◽  
X Ray ◽  
Distorted Tetrahedral Geometry ◽  
Cobalt Center

Chemical treatment of CoX<sub>2</sub><b><sup>. </sup></b>6H<sub>2</sub>O (X = Cl, Br, I) with the potentially tridentate PNP pincer ligand 2,6-bis(di-<i>tert</i>-butylphosphinomethyl)pyridine in 1:1 molar ratio results in cobalt(II) halide-PNP pincer complexes. The effect of the hydrated metal source on molecular structure and geometry of the complexes was studied by single crystal X-ray diffraction analysis. The complexes are neutral and the cobalt center adopts a penta-coordinate system with potential atropisomerization. Within the unit cell there are two distinct molecules per asymmetric unit. One of the two phosphorus atoms in the PNP ligand was observed to be partially oxidized to phosphinoxide. Disorder in the structure reflects a mixture of square pyramidal and distorted tetrahedral geometry.

scholarly journals Reversible magnetism switching of iron oxide nanoparticle dispersions by controlled agglomeration

2021 ◽  
Author(s):  
Stephan Müssig ◽  
Björn Kuttich ◽  
Florian Fidler ◽  
Daniel Haddad ◽  
Susanne Wintzheimer ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Light Scattering ◽  
Superparamagnetic Iron Oxide ◽  
Iron Oxide Nanoparticle ◽  
Oxide Nanoparticles ◽  
X Ray ◽  
X Ray Scattering ◽  
Nanoparticle Dispersions ◽  
Oxide Nanoparticle

The controlled agglomeration of superparamagnetic iron oxide nanoparticles (SPIONs) was used to rapidly switch their magnetic properties. Small-angle X-ray scattering (SAXS) and dynamic light scattering showed that tailored iron oxide...

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

scholarly journals Direct Production of a Novel Iron-Based Nanocomposite from the Laser Pyrolysis ofFe(CO)5/MMAMixtures: Structural and Sensing Properties

2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
R. Alexandrescu ◽  
I. Morjan ◽  
A. Tomescu ◽  
C. E. Simion ◽  
M. Scarisoreanu ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Gas Sensors ◽  
High Sensitivity ◽  
X Ray Diffraction ◽  
Direct Production ◽  
X Ray ◽  
Metallic Particles ◽  
Ir Laser ◽  
Iron Iron ◽  
Optimum Working

Iron/iron oxide-based nanocomposites were prepared by IR laser sensitized pyrolysis ofFe(CO)5and methyl methacrylate (MMA) mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core-shell structures were obtained. X-ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized) polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence ofNO2, CO, andCO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towardsNO2detection andNO2selectivity relatively to CO andCO2. An optimum working temperature of200°Cwas found.

scholarly journals Discovery of Fe7O9: a new iron oxide with a complex monoclinic structure

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Ryosuke Sinmyo ◽  
Elena Bykova ◽  
Sergey V. Ovsyannikov ◽  
Catherine McCammon ◽  
Ilya Kupenko ◽  
...  
Keyword(s):  
Applied Sciences ◽  
Crystal Structure ◽  
Iron Oxide ◽  
Iron Oxides ◽  
Industrial Applications ◽  
Ambient Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Insight Into

Abstract Iron oxides are fundamentally important compounds for basic and applied sciences as well as in numerous industrial applications. In this work we report the synthesis and investigation of a new binary iron oxide with the hitherto unknown stoichiometry of Fe7O9. This new oxide was synthesized at high-pressure high-temperature (HP-HT) conditions, and its black single crystals were successfully recovered at ambient conditions. By means of single crystal X-ray diffraction we determined that Fe7O9 adopts a monoclinic C2/m lattice with the most distorted crystal structure among the binary iron oxides known to date. The synthesis of Fe7O9 opens a new portal to exotic iron-rich (M,Fe)7O9 oxides with unusual stoichiometry and distorted crystal structures. Moreover, the crystal structure and phase relations of such new iron oxide groups may provide new insight into the cycling of volatiles in the Earth’s interior.

Sign in / Sign up

Export Citation Format

Share Document