Cu-doped TiO2 porous discs: A novel photo-enzyme catalyst for enhanced antibacterial activity and oral ulcer treatment

Abstract

The global challenge of bacterial infections and antibiotic resistance underscores the urgent need for innovative antimicrobial strategies, with emerging photodynamic therapy using photocatalysts and nanozyme technologies showing promise in addressing multidrug-resistant pathogens. However, limited research exists on synergistic systems integrating both photocatalysts and nanoenzymes, highlighting a vital gap requiring systematic exploration. This study addresses this void through the rational design of copper-doped titanium dioxide (Cu-TiO₂) porous disc catalysts that synergistically combine photocatalytic activity with light-activated enzymatic activity. The optimized Cu doping strategy substantially improved charge separation efficiency and redox capacity, while the hierarchical porous architecture maximized reactive oxygen species (ROS) generation through exposing of abundant active sites and enhancing mass transport of reactants. Under Xe light irradiation, the engineered Cu-TiO₂ demonstrated exceptional antimicrobial efficacy, achieving 99.7 % eradication of ampicillin-resistant Escherichia coli (AREC) within 45 minutes and 97.5 % elimination of methicillin-resistant Staphylococcus aureus (MRSA) within 60 minutes. Notably, the integration with low-concentration H₂O₂ under illumination activated photo-enhanced peroxidase-mimicking activity, enabling 99.3 % MRSA inactivation within 30 minutes. Practical validation through hydrogel-mediated treatment of oral ulcer infections confirmed accelerated wound healing and infection control. This bifunctional catalysts establishes a new paradigm for developing light-responsive antimicrobial agents, offering transformative potential for combating antibiotic-resistant infections in biomedical and environmental applications through ROS-mediated multimodal disinfection mechanisms.