Preparation and characterization of magnetic carboxymethyl chitosan/Fe3O4 composite nanoparticles

Monodisperse carboxymethyl chitosan-bound Fe₃O₄ magnetic nanoparticles can be potentially used as drug delivery carrier and a novel magnetic nano-adsorbent for the removal of pollutants from aqueous solutions. In this paper, the magnetic chitosan nanoparticles of about 20 nm were prepared by the carboxymethylation of chitosan and the followed binding on the surface of Fe₃O₄ nanoparticles which were prepared using a coprecipitation method The images of transmission electron microscope showed that the magnetic iron oxide particles were encapsulated by the spherical chitosan nanoparticles. XRD indicated that the magnetic component of the composite nanoparticles were validated as Fe₃O₄. FTIR spectra confirmed the carboxymethyl reaction of chitosan and the binding of carboxylmethyl chitosan on Fe₃O₄. The saturated magnetization of composite nanoparticles could reach 25.7 emu/g. Meanwhile, the nanoparticles showed the characteristics of superparamagnetism.