Glutathione-depletion reinforced enzyme catalytic activity for photothermal assisted bacterial killing by hollow mesoporous CuO

Abstract

The emergence and prevalence of drug-resistant bacteria caused by the overuse of antibiotics pose new challenges to the treatment of bacterial infections. In this work, hollow mesoporous CuO nanozymes (HM-CuO nanozymes) as excellent antibacterial agents were prepared by a template method. The synthesized HM-CuO nanozymes exhibit peroxidase-like catalytic activity, which can efficiently catalyze H₂O₂ to generate toxic reactive oxygen species (ROS), causing fatal damage to bacteria. Moreover, the hyperthermia of HM-CuO produced by photothermal therapy (PTT) not only effectively kills bacteria but also enhances the catalytic activity of nanozymes and produces more ROS. Moreover, the HM-CuO nanozymes have a glutathione (GSH)-depleting function to effectively consume GSH in bacteria and generate Cu(I) with higher catalytic effect, which can significantly improve the sterilization effect and produce a 100% inhibitory rate against E. coli and S. aureus. Overall, the HM-CuO nanozymes with strong peroxidase-like catalytic activity, excellent photothermal performance and GSH consumption ability offer a promising synergistic strategy for clinical bacterial infection.