Synthesize and Characterization of Multifunctional Silica Coated Magnetic Nanoparticles Using Polyvinylpyrrolidone (PVP) as a Mediator

2012 ◽  
Vol 16 ◽  
pp. 43-48 ◽  
Author(s):  
Mirabdullah Seyed Sadjadi ◽  
F. Fathi ◽  
Nazanin Farhadyar ◽  
K. Zare

Magnetic iron oxide nanoparticles with proper surface coatings are increasingly being evaluated for clinical applications such as hyperthermia, drug delivery, magnetic resonance imaging, transfection and cell/protein separations. In this work, silica coated iron oxide magnetic nanoparticles, which are very useful for delivering chemotherapeutic drugs, has been prepared by precipitation in an aqueous solution of iron (II) and iron (III) chlorides under basic condition. In this process, polyvinylpyrrolidone (PVP) has been used as a stablizer. Surface modifications of the as-prepared Fe3O4 Nps have been carried out by using tetraethoxysilane (TEOS). Silica coated nanoparticles have been characterized by Fourier transform infrared (FTIR) spectroscopy, Powder X- ray diffraction (XRD), Transmission electron microscopy (TEM) and Infrared (IR) spectroscopy

Nukleonika ◽  
2017 ◽  
Vol 62 (2) ◽  
pp. 73-77 ◽  
Author(s):  
Zbigniew Surowiec ◽  
Mieczysław Budzyński ◽  
Katarzyna Durak ◽  
Grzegorz Czernel

Abstract Small particles of magnetite, i.e. 7.5, 13.4 and 14.1 nm in diameter, were obtained by the method of co-precipitation. The crystal structure and size distributions were determined by means of transmission electron microscopy and X-ray diffraction. The magnetic properties of the nanoparticles were tested by Mössbauer spectroscopy within the temperature range from 3 K to room temperature (RT). The Mössbauer study of magnetic nanoparticles reveals relaxation behaviour related to the existence of the superparamagnetic phase. The blocking temperature depends on the sizes of the nanoparticles and the ammonia concentration.


Author(s):  
Venkat S. Kalambur ◽  
Ellen Longmire ◽  
John C. Bischof

Magnetic iron oxide nanoparticles (NPs) have intrinsic advantages over other NPs for various biomedical applications. These advantages include visualization under Magnetic Resonance Imaging (MRI), heating with Radiofrequency (RF), and movement in a magnetic field. There are now numerous efforts to expand the applications of these particles for non-invasive drug and adjuvant delivery, cellular imaging and in vitro cell sorting and purification. In the present study, we describe methods to (i) assess and quantify NP cell association (ii) facilitate NP heat destruction of cells after association with RF and laser. First, we show that (i) the cell association of iron oxide NPs is dependent on the surface coating (surfactant greater than dextran), time, cell-type and extracellular NP concentrations (saturation with concentration and time). Furthermore, the association fits a simple enzyme Michealis-Menten model. Second, (ii) improved heat destruction of cells can be achieved after laser irradiation compared to traditional RF treatment for similar NP associations. These results and assays show promise for cell sorting and purification applications.


2014 ◽  
Vol 70 (6) ◽  
pp. 1004-1010 ◽  
Author(s):  
Th. I. Shalaby ◽  
N. M. Fikrt ◽  
M. M. Mohamed ◽  
M. F. El Kady

This study investigated the applicability of magnetite Fe3O4 nanoparticles coated with chitosan (CMNs) for the removal of some toxic heavy metals from simulated wastewater. Magnetic nanomaterials were synthesized using the co-precipitation method and characterized by transmission electron microscope, scanning electron microscope, X-ray diffraction, and Fourier transformer infrared spectroscopy. The magnetic properties of the prepared magnetic nanoparticles were determined by a vibrating-sample magnetometer. Batch experiments were carried out to determine the adsorption kinetics of Cr(VI) and Cd(II) by magnetic nanoparticles. It is noteworthy that CMNs show a highly efficient adsorption capacity for low concentration Cr(VI) and Cd(II) ions solution, which can reach 98% within 10 min.


2013 ◽  
Vol 27 (19) ◽  
pp. 1341002 ◽  
Author(s):  
YUHONG ZHANG ◽  
BIAO YAN ◽  
TAIGANG SHI

Amino-modified Fe 3 O 4 magnetic nanocomposite particles were prepared by one-step glycothermal method. The shape and morphology of Fe 3 O 4 particles change when a small amount of water is added as a co-solvent in the glycothermal method. The morphology and structure of the sample were characterized and measured by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. TEM images show that the morphology of the samples is from irregular polyhedron to spherical particles. Average diameter of particles is approximately 70/40/10 nm and more evenly distributed. XRD results show that the samples are cubic spinel structure. FTIR results show that a chemical bonds combination exists between the amino and iron oxide, nano-iron oxide are modified by the amino.


MRS Advances ◽  
2017 ◽  
Vol 2 (49) ◽  
pp. 2769-2773
Author(s):  
Morales P. Patricio ◽  
Moncayo H. José María ◽  
García R. Miguel ◽  
Santoyo S. Jaime

ABSTRACTMagnetic nanoparticles were obtained by chemical coprecipitation technique from aqueous solutions of iron salts, the synthesis was carried out in an alkaline medium, obtaining magnetic nanoparticles of around 2-10 nm in size. The nanoparticles obtained were stabilized with polyvinylpirrolidone (PVP), the particle size was measured by transmission electron microscopy (TEM), the crystal structure of the magnetic nanoparticles obtained was verified by X-ray diffraction (DRX). The chemical composition of the nanoparticles powder was investigated using electron scanning microscope with energy dispersive X-ray spectroscopy (EDX) equipment. Optical properties as absorption was studied by UV-Vis spectroscopy.


2018 ◽  
Vol 169 ◽  
pp. 126-134 ◽  
Author(s):  
Ruta Gruskiene ◽  
Tatjana Krivorotova ◽  
Ramune Staneviciene ◽  
Dalius Ratautas ◽  
Elena Serviene ◽  
...  

2019 ◽  
Vol 489 (2) ◽  
pp. 157-160
Author(s):  
V. E. Prusakov ◽  
Yu. V. Maksimov ◽  
V. A. Beglov ◽  
M. V. Gerasimov ◽  
A. V. Bychkova ◽  
...  

The novel biodegradable biocomposites on the base of poly(3-hydroxybutyrare) nanofibers with embedded iron oxide nanoparticles have been studied by transmission electron microscopy (TEM), Mssbayer spectroscopy, small angle X‑ray scattering (SAXS), and macroscopic magnetization techniques.


2015 ◽  
Vol 60 (2) ◽  
pp. 1159-1163 ◽  
Author(s):  
Ri Yu ◽  
Jiyeon Yun ◽  
Yoojin Kim

Abstract In this work is described a means of improving the chemical stability of Cu2O@SiO2, Cu2O@SnO2 and Cu2O@TiO2 materials. The SiO2, SnO2 and TiO2 coated samples were stable from pH 3 to pH 10 for up to seven days. To determine the stability of the coated nanoparticles, and their colloidal solutions under acidic and basic conditions, colloidal nanoparticle solutions with various pH values were prepared and monitored over time. Details of the effect of variations in pH on the phase stability of core-shell type Cu2O were characterized using transmission electron microscopy and X-ray diffraction.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2021 ◽  
pp. 089270572098557
Author(s):  
M Abu-Abdeen ◽  
O Saber ◽  
E Mousa

A solvent thermal method which depends on a thermal process under critical temperature and pressure was used to prepare cobalt iron oxide magnetic nanoparticles with a molar ratio 2. The prepared particles were in the form of nanoparticles with diameter ranging from 5 to 10 nm and with amorphous structure. Magnetic hysteresis behavior with saturation magnetization 36.31 emu/g and coercivity 4 Oe were observed for the nanoparticles. Polyvinyl alcohol was loaded with different concentrations of cobalt iron oxide nanoparticles using casting technique. Hysteresis loops for the polymer films were observed and both the saturation magnetization and coercivity were increased from 0.36 to 16.03 emu/g and 115 to 293 Oe for samples containing 5 and 20 wt% of nanoparticles, respectively. The elastic modulus of films was increased from 2.7 to 4.9 GPa for unloaded and loaded samples with 20 wt%, respectively. The storage modulus of the polymer films was found to obey the percolation behavior.


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