In this work, we present the process of synthesis, characterization and evaluation of biocompatibility of aqueous suspensions of magnetite-maghemite nanoparticles stabilized with quaternized chitosan. The nanocomposites were obtained by the coprecipitation method of Fe2+ and Fe3+ species in a quaternized chitosan solution. Chemical, structural, morphological and magnetic analyses confirmed that the nanocomposites synthesized are composed of magnetite-maghemite nanoparticles coated by quaternized chitosan chains with positive surface charge, giving them a good colloidal stability. The potential cytotoxic effect of the nanocomposite’s suspension was determined using both MTT and alamarBlue viability assays in cultures of the murine macrophage cell line J774 and the breast cancer cell line MCF-7. The results show that, after 24 h of incubation, J774 cells treated with nanocomposites with iron contents up to 100 ppm and MCF-7 cells treated with nanocomposites with iron contents up to 30 ppm presented both a viability above 70 %. Our results support the hypothesis that the synthesized aqueous suspensions of magnetic nanocomposites are biocompatible, which opens a door to their use in future biomedical applications.
Read full abstract