Blade-like structure of graphene oxide sheets decorated with cuprous oxide and silicon carbide nanocomposites as bactericidal materials

In the current work, graphene oxide nanosheets decorated with cuprous oxide nanospheres (GO/Cu2O) and with silicon carbide nanowires (GO/SiC) were synthesized and controlled for using as blade-like antibacterial agents. Preparation of GO sheets with <2 nm thickness was performed through a modified Hummers approach. Controlled Cu2O spheres with a mean size of 40 nm were prepared through a wetchemical approach. For comparative studies, a single step chemical deposition method was used to prepare GO/Cu2O and GO/SiC nanocomposites for using as antibacterial active materials. The nanomaterials' biological behavior and bacterial-resistance were assessed via selected Gram-negative and gram-positive bacteria and yeast strains. GO/Cu2O nanocomposite exhibited higher antibacterial activity against different bacterial strains than GO/SiC composite. GO/Cu2O exhibited average activity index, minimum inhibitory concentration (MIC) values, and viable cell numbers of 1.523, 10.438 mu g/mL, and 82.962% for Bacillus subtilis, Brevibacillus brevis and Bacillus thuriginesis), 1.453, 32.00 mu g/mL, and 68.418% for Pseudomonas aeruginosa and Escherichia coli) and 68.608% for Candida albicans, respectively. The antimicrobial efficiency of the blade-like GO/Cu2O was elucidated by scanning electron microscopy through the complete wrapping of the cell membranes and disrupting their shape morphology. GO nanosheets could increase the Cu2O dispersion in the aqueous solution, prevent their agglomeration, and stabilize its action in aqueous solution with high microbial toxicity. (C) 2020 Elsevier Inc. All rights reserved.