Synthesis of Magnetic Nanoparticles and Magnetic Fluids for Biomedical Applications

Abstract

Chemical coprecipitation and gas-phase laser pyrolysis procedures were applied to obtain various iron-based magnetic nanoparticles (magnetite, maghemite, and carbon layer-coated iron) in the size range of 3-15 nm used as basic building blocks for functionalized core-shell particles, magnetic nanofluids, as well as multifunctional hybrid nanostructures based on stimuli-responsive biocompatible polymers and block copolymers. The particle size distribution, magnetostatic properties, surface coating efficiency, and embedding/encapsulation mechanisms of magnetic nanoparticles and particle clusters in various biocompatible polymer matrices (core-shell nanostructures, microgels, and micelles) were examined by TEM/HRTEM, vibrational sample magnetometry, dynamic light scattering, Fourier transform infrared spectroscopy, and small-angle neutron scattering. The novel magnetic hybrid nanostructured materials envisaged for MRI contrast agents, magnetic carriers in bioseparation equipment, or magnetothermally triggered drug delivery systems have superparamagnetic behaviour and exhibit magneto-and thermoresponsive properties, high stability, and in vitro biocompatibility. Copyright (C) 2011 S. Karger AG, Basel