Cytotoxicity of Bacteriostatic Reduced Graphene Oxide-Based Copper Oxide Nanocomposites

An antibacterial nanocomposite, reduced graphene oxide-based copper oxide (CuO-RGO), was prepared by a one-step hydrothermal method and characterized by x-ray diffraction analysis, infrared absorption spectroscopy, scanning electron microscopy, transmission electron microscopy, and photoluminescence measurements, revealing CuO nanoparticles with diameter of about 26 nm uniformly anchored on graphene sheets. Compared with recently reported bacteriostatic agents, much less CuO-RGO is required and better bacteriostatic effect is achieved, with good stability. The minimum inhibitory concentration of the CuO-RGO composite against Escherichia coli reached 240 μg mL−1. The antibacterial rate remained at 89% after five cycles. In addition, introduction of graphene inhibited leaching of Cu2+, which reduces the cytotoxicity of CuO-RGO to mouse fibroblast L929.