Triple-Shielded Microneedle Patch: A Synergistic Approach to Combat Infection, Oxidation and Inflammation in Wound Healing.

The rapid healing of infected wounds remains a critical clinical challenge, as it is driven by a pathological cascade of persistent inflammation, excessive oxidative stress, and microbial colonization that collectively compromise tissue regeneration. Herein, to address these interconnected barriers, we developed a synergistic tri-functional (three-effect) therapeutic microneedle patch (MN-AT). The developed MN-AT platform was engineered using a biocompatible thiolated chitosan (CSSH)/polyvinyl alcohol (PVA) viscoelastic hydrogel as the matrix, integrated with a tea polyphenol-magnesium (TP-Mg) antioxidant complex, and surface-functionalized through grafting of amino-terminated gold nanoparticles (AuNPs). In vitro studies demonstrated that the as-fabricated MN-AT platform can simultaneously achieve: (1) potent antibacterial activity, (2) effective free radical scavenging to mitigate oxidative stress, and (3) suppression of excessive inflammation through macrophage polarization modulation - thereby remodeling the immune microenvironment into a pro-healing state. In a murine infection model, the use of MN-AT patch significantly accelerated wound closure and enhanced collagen deposition. This multifunctional microneedle patch system presents an efficient and innovative strategy for infected wound treatment via synergistic antibacterial, antioxidant, and anti-inflammatory actions.