Self-sufficient Fe/Mn@CuO₂ nanozyme with cascade ROS amplification and GSH depletion for superior antibiofilm and bactericidal performance

The escalating challenge of bacterial resistance necessitates the development of novel antibacterial agents, positioning the synthesis of nanomaterials as a pivotal strategy for controlling pathogenic bacteria in the food sector. In this study, a novel H₂O₂ self-supplying nanocomposite was developed, comprising Fe/Mn nanoparticles functionalized with cuprous oxide (CuO₂), denoted as Fe/Mn@CuO₂. This composite exhibit tandem peroxidase (POD)-mimetic and glutathione (GSH)-depleting activities, enabling the on-demand generation of hydroxyl radicals via self-produced H₂O₂ and O₂ under acidic conditions (pH 5.5). The synergistic integration of H₂O₂ self-generation, POD-like catalysis, and GSH consumption significantly enhanced reactive oxygen species (ROS) production, leading to efficient eradication of E. coli (99.4%) and Staphylococcus aureus (99.1%) and remarkably antibiofilm efficacy. This multi-mechanistic action induced pronounced morphological alterations and severe membrane disruption in both bacterial strains. Furthermore, Fe/Mn@CuO₂ demonstrated the ability to denature DNA/RNA, disrupt energy metabolism, and achieve potent bacterial inactivation without detectable cytotoxic side effects. This work marked a substantial advancement in overcoming the drawbacks of conventional bactericidal strategy by combining self-sustaining H₂O₂ supply, POD-like activity, and GSH depletion, thereby presenting a highly promising antibacterial platform. Download: Download high-res image (304KB) Download: Download full-size image