Application of a Cascaded Nanozyme in Infected Wound Recovery of Diabetic Mice

The emergence of peroxidase (POD)-like nanozyme-derived catalytic therapy has provided a promising choice for reactive oxygen species (ROS)-mediated broad-spectrum antibacterials to replace antibiotics, but it still suffers from limitations of low therapeutic efficiency and unusual addition of unstable H 2 O 2 . Considering that the higher blood glucose in diabetic wounds provides much more numerous nutrients for bacterial growth, a cascade nanoenzymatic active material was developed by coating glucose oxidase (GOx) onto POD-like Fe 2 (MoO 4 ) 3 [Fe 2 (MoO 4 ) 3 @GOx]. GOx could consume the nutrient of glucose to produce gluconic acid (weakly acidic) and H 2 O 2, which could be subsequently converted into highly oxidative • OH via the catalysis of POD-like Fe 2 (MoO 4 ) 3 . Accordingly, the synergistic effect of starvation and ROS-mediated therapy showed significantly efficient antibacterial effect while avoiding the external addition of H 2 O 2 that affects the stability and efficacy of the therapy system. Compared with the bactericidal rates of 46.2–59.404% of GOx or Fe 2 (MoO 4 ) 3 alone on extended-spectrum β-lactamases producing Escherichia coli and methicillin-resistant Staphylococcus aureus, those of the Fe 2 (MoO 4 ) 3 @GOx group are 98.396 and 98.776%, respectively. Animal experiments showed that the as-synthesized Fe 2 (MoO 4 ) 3 @GOx could much efficiently promote the recovery of infected wounds in type 2 diabetic mice while showing low cytotoxicity in vivo .