Pioneering bactericidal efficacy with nitrogen doping and zinc oxide nanoparticle decoration on carbon nanosheets†

Abstract

The escalating prevalence of drug-resistant pathogens poses a significant threat to global health, contributing to elevated mortality rates and inflated healthcare expenses. To combat antibacterial resistance, carbon-based nanocomposites incorporating metal oxides have emerged as a promising solution in the development of advanced antibacterial agents. In this quest, we propose a nascent strategy to synthesize zinc oxide-decorated carbon nanosheets (ZnO@CNSn) via a co-precipitation method. The crystalline ZnO nanoparticles (ZnO-NPs) are homogeneously dispersed throughout a framework of melamine-enriched carbon nanosheets (CNSn). The presence of pyrrolic-N and pyridinic-N functionalities in ZnO@CNSn enhances the charge transfer kinetics and creates nucleation sites for uniform dispersion of ZnO-NPs, mitigating particle aggregation. Remarkably, XPS analysis reveals a distinct shift in peak intensity, characterized by a reduction in pyrrolic-N and a corresponding increase in pyridinic-N. This conversion of pyrrolic-N to pyridinic-N due to incorporation of ZnO-NPs onto CNSn plays a crucial role in improving its bactericidal effect. The antibacterial assays against Gram negative Escherichia coli, Gram positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) confirm the bactericidal activity of ZnO@CNSn. Additionally, the SEM micrographs show altered bacterial morphology on interaction with the nanocomposites, further validating the effective bactericidal properties. Moreover, ZnO@CNSn exhibits enhanced cytocompatibility compared to CNSn. These findings underscore the promising potential of the ZnO-decorated CNSn architecture as a robust platform for advanced antibacterial applications.