Key Words:Magnetite-silica nanoparticles; Core-shell structure; Direct silicon oxidation; Relaxation property

Abstract:Magnetite-silica core-shell nanoparticles (Fe3O4@SiO2 NPs) were prepared from silicon powder by direct oxidation without using any expensive precursors (such as TEOS) and organic solvents. The as-prepared Fe3O4@SiO2 NPs were characterized by TEM, DLS, XRD, FT-IR, zeta potential and NMR Analyzer. The results show that the Fe3O4@SiO2 NPs are monodispersed core-shell nanostructures with single cores that were uniformly coated by silica shells. The relaxation property indicates that Fe3O4@SiO2 NPs have desirable characteristics for T-2 MRI contrast agents. This facile and green method is promising for large-scale production, which would open new opportunities for preparing core-shell nanostructures for biomedical applications. (C) 2014 Elsevier Inc. All rights reserved.

Volume:432

Translation or Not:no