Photo-regulated dual-functional zinc oxide nanocomposite for synergistic sterilization and antioxidant treatment

Bacterial infections represent one of the most critical health challenges worldwide, while the long-term use of antibiotics is leading to the development of bacterial resistance, which dramatically weakens the antibacterial efficacy of antibiotics. Zinc oxide nanoparticles (ZnO NPs) can effectively reduce bacterial resistance by opening new antibacterial pathways due to their distinctive physico-chemical properties. However, the antioxidant enzymes produced by bacteria against this pathway generate further bacterial resistance. Herein, ZnO NP composites combining carboxymethyl chitosan (CMC) and rutin (RT) effectively exploited the antibacterial advantages of CMC and RT to further enhance their antibacterial activity, enabling this composite to accomplish synergistic antibacterial and antioxidant effects causing cell membrane damage and oxidative damage under illuminated conditions, achieving outstanding sterilization performance against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus).