Synthesis and characterization of chitosan/iron oxide nanocomposite for biomedical applications.

The structural and optical properties of metal oxide nanoparticles exhibit remarkable changes when coated with organic polymers. In this work, we report the preparation of chitosan (CS) coated iron oxide nanocomposite using rutin by a facile greener route. The formation of iron oxide nanoparticles (FeO NPs) and CS coated iron oxide nanocomposite (CS-FeO) were preliminarily confirmed by color change and UV-Visible spectroscopy. FE-SEM images of FeO NPs revealed rod shaped agglomerated particles whereas CS-FeO nanocomposite showed rod shaped agglomerated small grains. TEM analysis revealed that the size of the nanoparticles varies from 20 to 90 nm. The observed bands at 500-800 cm-1 in the FTIR spectrum indicated the presence of metal‑oxygen (FeO) bond, whereas band at 1646 cm-1 indicated the presence of amino groups (-NH2) which confirms the CS in the prepared CS-FeO nanocomposite. The prepared nanoparticles showed potential antibacterial activity against both Gram-positive and Gram-negative bacterial pathogens. The antioxidant activity of FeO NPs and CS-FeO nanocomposite was evaluated by DPPH and H2O2 assays. The percentage of antioxidant activity was increased with increasing concentration of FeO NPs and CS-FeO nanocomposite. CS-FeO nanocomposite exhibiting potentially better biomedical property than the uncoated FeO NPs indicates that CS-FeO nanocomposite is a promising bio-nanomaterial for many biological applications.