摘要:Copper Oxide nanoparticles (NPs) have shown great acceptance in the antimicrobial application owing to their low toxicity and high surface to charge ratio. In this study, copper oxide NPs (represented as S-1, S-2 and S-3) were prepared by a simple and cost-effective thermal approach in three different environments. Fabricated NPs were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) spectroscopy and Fourier transform infrared spectroscopy (FTIR) technique. The XRD patterns revealed that the synthesized S-2 was of pure Cu2O phase while S-3 was composed of monoclinic CuO with a small quantity of Cu2O. More importantly, synthesized copper oxide NPs were used to evaluate the antimicrobial activity against three types of gram-negative bacteria namely Salmonella typhi, SK4 and E. coli (two strains). Although the NPs produced from the S-1 approach did not show encouraging results, the copper oxide NPs from S-2 and S-3 had shown enhanced antimicrobial activity. The successful antimicrobial activity of S-2 and S-3 can be related to the release of Cu+ and Cu2+ ions into the surrounding environment, which is responsible for the breaking of the cell wall membrane and ultimately causes bacterial cell disruption. The synthesized copper oxide NPs via thermal approach will be good candidates for biomedical applications.