Enzyme-responsive microneedle patch for bacterial infection and accelerated healing of diabetic wounds

Chronic diabetic wounds are caused by an array of pathologies. Pathogenic bacteria such as S. aureus can easily invade hosts with deficient immunity. In this study, we developed a multifunctional hyaluronic acid methacrylate (HAMA)/carboxymethyl chitosan (CMCS) core‐shell microneedle patch with sodium alginate as a moisture layer to maintain the moisture balance in the wound exudate. Microneedles are stably held on the wound by a chitosan adhesive layer. Sufficient strength supports microneedle to punch into the biofilm and induce dispersion. S. aureus secreted hyaluronidase to degrade the HAMA shell of the microneedle and promote the release of graphene oxide with ASyycF, triggering strong antibacterial activity by posttranscriptional regulation and physical cutting effects. The continual release of basic fibroblast growth factor from the CMCS core was able to accelerate angiogenesis, collagen synthesis and immunity modulation, working synergistically with biodegraded HAMA. The multifunctional microneedle patches thereby provide a potential approach by accelerating the healing of infected diabetic wounds.