Synthesis and study of structural and magnetic properties of superparamagnetic Fe3O4@SiO2 core/shell nanocomposite for biomedical applications


1 Department of Physics, Ferdowsi University of Mashhad, Mashhad, Iran

2 Nanoscience Center, Ferdowsi University of Mashhad, Mashhad, Iran

3 Department of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran


This paper describes coating of magnetite nanoparticles (MNPs) with amorphous silica shells.
Materials and Methods:
First, magnetite (Fe3O4) NPs were synthesized by co-precipitation method and then treated with stabilizer molecule of trisodium citrate to enhance their dispersibility. Afterwards, coating with silica was carried out via a sol-gel approach in which the electrostatically stabilized MNPs were used as seeds. The samples were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and vibrating sample magnetometer (VSM).
The results of XRD analysis implied that the prepared nanocomposite consists of two compounds of crystalline magnetite and amorphous silica that formation of their core/shell structure with the shell thickness of about 5 nm was confirmed by TEM images. The magnetic studies also indicated that produced Fe3O4@SiO2 core/shell nanocomposite exhibits superparamagnetic properties at room temperature.
These core/shell structure due to having superparamagnetic property of Fe3O4 and unique properties of SiO2, offers a high potential for many biomedical applications.


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