Ultratiny Scale Patterned Biomedical Janus Patch with Adhesive and Anti-Adhesive Properties

Tissue adhesion barriers are essential for biomedical applications to prevent postoperative surgical complications and promote tissue regeneration. However, existing solutions often fall short because of inadequate adhesion strength, which hinders effective wound healing. Herein, we introduce an innovative dual-functional Janus patch featuring ultratiny scale patterned surfaces, uniquely designed to provide synergistic adhesive and antiadhesive properties. The Janus patch integrates a microsharp antiadhesive surface and a mushroom-shaped adhesive surface created from poly(lactic-<i>co</i>-glycolic) acid and chitosan. The patch was meticulously optimized to achieve excellent mechanical stability and adhesion performance under dry and wet conditions. Comprehensive <i>in vitro</i> (NIH3T3 fibroblast-based) and <i>ex vivo</i> (porcine tissue-based) tests confirmed its regenerative potential, accelerate wound healing, and strengthen tissue adhesion. Our findings suggest that ultratiny scale patterned Janus patches represent a transformative advancement in tissue engineering, offering a next-generation platform for hierarchically designed biomaterials that can redefine patient care and recovery across diverse biomedical applications.