Study of spinel-based nanocomposites

Abstract Novel multifunctional nanocomposites 0.3CoFe 2 O 4 /0.7Ag 0.5 Cr 2.5 O 4 (Co) and 0.3CuFe 2 O 4 /0.7Ag 0.5 Cr 2.5 O 4 (Cu) were prepared using the flash auto-combustion technique. The crystallite size was calculated from an X-ray diffraction pattern (XRD), and the morphology was studied using atomic force microscopy (AFM). The structural properties were analyzed to ensure the nanoscale nature of the samples. The Co nanocomposite exhibited a 5.7-fold larger coercivity ( H c ) and a 2.6-fold larger saturation magnetization ( M s ) than the Cu nanocomposite. Moreover, the high-frequency applications of Co nanocomposite suggest its suitability in the super high frequency range in the microwave range at the S band, whereas the Cu nanocomposite is more suitable for ultra-high frequency in the microwave region at the L band. The materials showed a strong synergistic anti-bacterial activity, with the Co nanocomposite achieving a minimum inhibitory concentration of 31.22 μg/ml against Salmonella typhimurium and Bacillus Subtilis . Furthermore, cytotoxicity tests of the optimal nanocomposite revealed low toxicity against normal Vero cells (CC 50 = 280.4 ± 19.3 μg/ml) and selective anti-cancer activity against HepG-2 cells (IC 50 = 26.7 ± 2.31 μg/ml). Thus, the investigated samples are strongly recommended to be anti-bacterial nanomaterials.