Synthesis and characterization of the iron oxide magnetic particles coated with chitosan biopolymer

Magnetic particles are extremely interesting for several biomedical applications; amongst these are therapeutic applications, such as: hyperthermia and release of drugs. The use of magnetic particles to induce hyperthermia in biological tissues is an important factor in cancer therapy. The aim of this study was to prepare and characterize iron oxide magnetic particles coated with biopolymer chitosan, and also to produce ferrofluids from the magnetic particles. The iron oxide magnetic particles (IOMP) were coated with chitosan (CS) by spray-drying method using two IOMP/coating ratios (IOMP/CS=1.6 and IOMP/CS=4.5). The magnetic particles were characterized by way of scanning electronic microscopy and energy-dispersive X-ray. The analysis by energy-dispersive X-ray was carried out to determine the chemical composition of particles in samples. The size distribution the iron oxide magnetic particles uncoated and coated were evaluated by the laser diffraction analysis and image analysis, respectively. Amongst the prepared ferrofluids, the sample IOMP/CS= 1.6 proved to be the one that has brought about the best results in therapeutics applications, such as in hyperthermia treatment. This sample was placed within an alternating magnetic field during 40 min, it was observed that 1 degrees C heated in 3 min and underwent a temperature variation of 7 degrees C, since it varied from 25 degrees C to 32 degrees C. Considering that the experiment would be carried out at body temperature 37 degrees C, probably, the temperature variation would be very close to the one reported at 25 degrees C. In such a way, the cancerous cells would reach 44-45 degrees C and at such temperatures the cancer cells generally perish. (c) 2007 Elsevier B.V. All rights reserved.