Copper Peroxide-Loaded Gelatin Sponges for Wound Dressings with Antimicrobial and Accelerating Healing Properties.

Catalytic conversion of hydrogen peroxide (H2O2) to more toxic hydroxyl radicals (•OH) is a good choice for sterilization and anti-infection, but endogenous H2O2 is insufficient to achieve satisfactory sterilization efficacy. Despite great efforts, designing and developing antimicrobial materials that specifically and effectively self-supply H2O2 at the wound site remain as tremendous challenges. Here, we report a pH-responsive copper peroxide-loaded wound dressing made from copper hydroxide and gelatin sponge and then reacted with H2O2. In vitro experiments show that the prepared wound dressing has good bactericidal properties against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa). Moreover, the as-prepared wound dressing can release •OH specifically in the bacterial-infected skin wound, rather than in normal tissues, and in vivo skin wound-healing experiments proved that the synthesized copper peroxide-loaded gelatin sponge could combat E. coli effectively; in addition, Cu2+ released from the gelatin sponge could stimulate angiogenesis and collagen deposition simultaneously. The study provides a strategy to improve antibacterial efficacy and reduce the toxic side effects through the release of •OH by bacterial self-activation.