Self-Powered Microneedle Patch with Synergistic Mild Microwave Thermal Therapy for Scarless Healing of Infected Diabetic Wound.

Diabetic wound healing remains a major challenge, as persistent bacterial infections and chronic inflammation can delay healing and lead to scar formation. Herein, a novel self-powered microneedle patch (SPMNP), combined with mild microwave thermal (MT) therapy, is developed to promote the scarless healing of infected diabetic wounds. The SPMNP is fabricated by integrating a piezoelectric nanogenerator (PENG) with a microneedle patch (CFeZ/MNP) loaded with Curcumin@Fe3O4-COOH@ZIF-8 nanoparticles (CFeZ NPs). The CFeZ NPs endow the CFeZ/MNP with a mild MT effect under microwave irradiation, enabling elimination of bacteria and biofilms. Owing to the boronic ester bonds and MT effect, CFeZ/MNP facilitates responsive release of curcumin under both the infected diabetic wound microenvironment and microwave irradiation. The PENG collects and converts biomechanical motion to electrical stimulation to further promote wound healing. In vitro experiments demonstrate that SPMNP synergizes with mild MT therapy to promote M2 macrophage polarization as well as enhance cell proliferation and migration. In a Staphylococcus aureus-infected diabetic wound model, the SPMNP combined with mild MT therapy can eliminate bacteria, inhibit inflammatory response and pro-fibrotic cytokines expression, promote tissue regeneration, and ultimately promote scarless healing of infected diabetic wound. This study provides a promising therapeutic strategy for the scarless healing of infected diabetic wounds.