Enzymatic metal oxide/nanoparticle heterojunctions with mutually reinforced bifunctional chemotherapies for combating drug-resistant bacteria

Non-healing diabetic wounds caused by continuous bacterial infections comprise one of the main complications in individuals with diabetes, posing a significant risk that often results in limb amputation. The growing concern of antibiotic resistance has prompted the exploration of non-antibiotic strategies to combat bacteria effectively. Here, an Ag-doped V2O5 (Ag-V2O5) heterojunction biocatalyst is designed to act as an artificial enzyme for the catalytic treatment of bacterial infections in rats' skin wounds through the bifunctional chemotherapies of reactive oxygen species (ROS) and Ag+. Experimental analyses confirm that the Ag-V2O5 catalyst exhibits exceptional peroxidase (POD)-mimetic performance, with a Vmax value of 2.66 µM s−1 and a turnover number of 200.88×10-3 s−1, surpassing most POD-mimetic catalysts. Furthermore, the Ag-V2O5 exhibits remarkable Ag+ leaching capabilities, attributed to its high V5+/V4+/3+ ratio and weak metal-support interactions. Benefiting from the bifunctional chemotherapies of ROS and Ag+, the Ag-V2O5 exhibits a low minimal inhibition concentration (32 μg/mL Ag-V2O5) against S. aureus and effectively promotes wound healing. The innovative strategy of bifunctional chemotherapies on valence-modulated Ag+ release and ROS-catalysis represents a significant leap forward in chronic wound treatment, inspiring future breakthroughs in biomedical therapeutics based on Ag+ and ROS.