Synthesis and characterization of a novel magnetic chitosan–nickel ferrite nanocomposite for antibacterial and antioxidant properties

Abstract A novel nanomagnet modified with nickel ferrite nanoparticles (NPs) coated with hybrid chitosan (Cs–NiFe2O4) was synthesized using the co-precipitation method. The resulting nanomagnets were characterized using various techniques. The size of the nanomagnetic particles was estimated to be about 40 nm based on the transmission electron microscopy (TEM) image and X-ray diffraction analysis (XRD) pattern (using the Debye–Scherrer equation). Scanning electron microscopy (SEM) images indicated that the surface of Cs–NiFe2O4 NPs is flatter and smoother than the uncoated NiFe2O4 NPs. According to value stream mapping (VSM) analysis, the magnetization value of Cs–NiFe2O4 NPs (17.34 emu/g) was significantly lower than NiFe2O4 NPs (40.67 emu/g). The Cs–NiFe2O4 NPs indicated higher antibacterial properties than NiFe2O4 NPs and Cs. The minimum inhibitory concentrations of Cs–NiFe2O4 NPs against S. aureus and E. coli were 128 and 256 mg/mL, respectively. Antioxidant activity (evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging test) for NiFe2O4 NPs and Cs–NiFe2O4 NPs at the concentration of 100 µg/mL were 35% and 42%, respectively. Consequently, the synthesized Cs–NiFe2O4 NPs can be proposed as a viable material for biomedical applications.