Artificial Skin Dressing With pH-Switchable Nanozyme Activity for Bidirectional ROS Regulation in Infected Diabetic...

Diabetic infected wounds heal poorly due to the synergistic effects of hyperglycemia, persistent microbial colonization, and chronic inflammation. We developed a pH-switchable artificial skin dressing TPI-PADL, to address these challenges. This system adapts to changes in the wound microenvironment over time. The dressing incorporates polydopamine and L-arginine modified PtAu nanozymes into a conductive ionogel-fiber scaffold. In the acidic and hyperglycemic conditions of early infection, the nanozymes exhibit glucose oxidase-like and cascade catalytic activities, increasing reactive oxygen species (ROS) production. The elevated ROS levels effectively kill bacteria and disrupt biofilms. As the wound environment shifts toward neutral pH, the nanozyme activity changes. The system begins to scavenge excess ROS and generate oxygen. The released oxygen reduces oxidative stress and improves local oxygen supply. These changes promote angiogenesis and guide macrophages toward a pro-healing phenotype. In vitro and in vivo evaluations confirm that TPI-PADL coordinates antibacterial, anti-inflammatory, antioxidant, and pro-regenerative effects. The ionogel network provides strain-sensing capability. This feature enables real-time monitoring of mechanical changes during healing. This strategy integrates therapy and sensing in a single platform for diabetic wound management.