Photothermal microneedle patch loaded with antimicrobial peptide/MnO2 hybrid nanoparticles for chronic wound healing

Chronic wound with complex clinical characteristics poses a significant challenge worldwide. Bioactive and stimulus responsive microneedle patch (MNP) has recently become one of the growing centers of wound healing, due to its suitability for suture-free tissue adhesion and transdermal cargo delivery. Herein, a series of double layer MNPs with dual antibacterial and reactive oxygen species (ROS)-scavenging abilities were firstly reported. Biocompatible methacrylated gelatin (GelMA) served as the base material of MNP. An artificial intelligence (AI)-derived antimicrobial peptide (AMP) was electrostatically assembled with hollow MnO2 nanoparticles, and then loaded onto microneedle tips. The products (named as GMCM) exhibited good photothermal conversion and anti-oxidative nanozyme activities. GMCM combined with low temperature photothermal therapy (LTPT) could not only relieve ROS-induced cell damage, but also inhibit the survival and proliferation of host bacteria. The broad-spectrum antibacterial activity of GMCM was solid, minimizing the potential of bacterial resistance. Wound healing evaluations were performed using a S. aureus infected skin defect model. The combination of GMCM and LTPT could complete the wound healing within 15 days, and the overall effect was better than that of product control (3 M®). In conclusion, this work will provide a competitive biomaterial for accelerating chronic wound healing.