MAGNETIC POLYSACCHARIDES

Magnetic composites with superparamagnetic properties has developed a great scientific interest in the last years by their potential application in drug delivery and cell sorting systems. Alginate, starch and chitosan were used as polymeric matrixes in order to obtain magnetic nanostructured composites. Magnetic nanocrystalline particles of iron oxide were formed inside the matrix by an in situ alkaline oxidation of iron (II) ions. The total iron content was determined in each composite. X-Ray Diffraction, Magnetometry and Mössbauer Spectroscopy were used to examine the composites. The magnetic materials exhibits high magnetic response, absense of hysteresis in the magnetization curves and a centered paramagnetic doublet in the Mössbauer spectra indicating the presence of nanocrystalline particles with a superparamagnetic behavior. X-Ray diffractograms show peaks that correspond to maghemite.