Preparation and characterization of (3-aminopropyl) triethoxysilane-coated magnetite nanoparticles

Magnetite nanoparticles coated with (3-aminopropyl)triethoxysilane, NH2(CH2)(3)Si(OC2H5)(3), were prepared by silanization reaction and characterized by X-ray diffractometry, transmission electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy and magnetization measurements. Both uncoated and organosilane-coated magnetite exhibited superparamagnetic behavior and strong magnetization at room temperature. Basic groups anchored on the external surface of the coated magnetite were observed. The superparamagnetic particles of coated magnetite are able to bind to biological molecules, drugs and metals and in this way remove them from medium by magnetic separation procedures. (C) 2004 Elsevier B.V. All rights reserved.