Characterization of ZnO-CuO and ZnO-CuO-NiO nanocomposites prepared by co-precipitation and antibacterial properties

Antibacterial resistance has become a global threat to health and development. Oxide nanoparticles are effective materials to overcome antibacterial resistance. In this study, ZnO-CuO-NiO nanoparticles were synthesized by co-precipitation with different NiO contents (0, 10, 20 and 30 wt%). The properties of the synthesized nanocomposite powder, including crystalline structure, size, morphology and composition, were investigated by FESEM, XRD and FTIR. The antibacterial effect of all nanocomposites was investigated using the disk diffusion method. Based on the metal-oxygen bonds in the FTIR spectra, the formation of metal oxides of Ni, Cu and Zn was confirmed. The results of XRD and FESEM proved the production of ZnO, CuO and NiO with a uniform elemental distribution and particle size < 150 nm with an irregular spherical morphology. All components showed desirable antibacterial activity against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. However, the level of antibacterial activity was significantly improved by the NiO nanoparticles in the component and at a low concentration of the nanocomposition of 1.25 and 0.313 mg/l, the Gram-negative and Gram-positive bacteria disappeared from the Petri dish for the ZnO-CuO-30% NiO sample, respectively, compared to > 10 and 5 mg/l for ZnO-CuO.