Abstract

Magnetic nanocomposite materials based on chitosan/ Fe3O4 were prepared by two different methods. The magnetic iron oxide nanoparticles were synthesized by co-precipitation method of solution containing Fe2+ and Fe3+ ions in NH4OH solution. The reaction temperature was kept at 70 °C for 2 hours under nitrogen atmosphere. The dispersion of Fe3O4 was subsequently dropped in chitosan solution 1 % w/v and stirred for one hour to afford magnetic nanocomposite (CS-ex). The magnetic nanocomposite was also synthesized by simple, one-pot in-situ co-precipitation method (CS-in). In this procedure, the ferrous and ferric salt were dissolved directly in chitosan solution and followed by the co-precipitation in NH4OH solution at 70 °C in nitrogen atmosphere. The samples were collected by a magnet and washed with deionized water and dried in vacuum at 50 °C. The results showed that the magnetic nanocomposite synthesized by in-situ coprecipitation exhibited the advantages in comparison with the CS-ex. CS-in contained 41 % of chitosan and had the nanosized scale of 11– 15 nm, saturation magnetization of 41,82 emu/g and was thermally stable than CS-ex.