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 methac-rylate (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 chitosan adhesive layer. Sufficient strength supports microneedle to punch into the biofilm and induce disper-sion. S. aureus secreted hyaluronidase to degrade the HAMA shell of the microneedle and promote the release graphene oxide with ASyycF, triggering strong antibacterial activity by posttranscriptional regulation physical cutting effects. The continual release of basic fibroblast growth factor from the CMCS core was able accelerate angiogenesis, collagen synthesis and immunity modulation, working synergistically with biodegraded HAMA. The multifunctional microneedle patches thereby provide a potential approach by accelerating healing of infected diabetic wounds.

Automated summary

In this study, a multifunctional hyaluronic acid methacrylate (HAMA)/carboxymethyl chitosan (CMCS) core-shell microneedle patch with sodium alginate as a moisture layer was developed to maintain moisture balance in diabetic wounds. The microneedles were held on the wound by a chitosan adhesive layer and had sufficient strength to penetrate the biofilm. S. aureus secreted hyaluronidase to degrade the HAMA shell and promote the release of graphene oxide, which exhibited strong antibacterial activity.