Synthesis, characterization, and in vitro anticancer evaluation of iron oxide/chitosan nanocomposites

Pure Fe3O4 and NiFe2O4 nanoparticles were synthesized and successfully coated with chitosan (CS). XRD patterns confirmed the formation of a pure spinel Fe3O4 and NiFe2O4 structure without presence of any other phases. TEM results revealed that the Fe3O4 and NiFe2O4 nanoparticles were 19.5 and 7.3 nm in size, respectively, with a good homogenous dispersion. The modification using chitosan did not result in a phase change. The binding of chitosan to the Fe3O4/NiFe2O4 nanoparticles was also demonstrated by the measurement of Fourier transform infrared spectra and thermogravimetric analysis. Magnetic measurements revealed that the saturated magnetization (M-s) was 77.6, 46.2, 8.42, and 49.8 emu/g for Fe3O4, NiFe2O4, Fe3O4/CS, and NiFe2O4/CS, respectively, which are also characteristics of superparamagnetic behavior. Exposure of breast MCF-7, liver HepG2, lung A549, and colon HCT116 human cancer cell lines to the prepared compounds (0-500 mu g/mL; 48 h) has resulted in a dose-dependent inhibition of cell growth determined by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay. Fe3O4/CS nanocomposite exhibited higher cytotoxic activity against liver cancer HepG2 cells whereas, NiFe2O4/CS nanocomposite demonstrated potent cytotoxic activity against both liver cancer HepG2 and human colon cancer HCT116 cell lines comparable to the activity of the commonly used anticancer drug doxorubicin.