Bioinspired Wet Adhesive Proanthocyanidins Microneedles for Ocular Wound Healing

Microneedles have shown considerable potential in treating ocular diseases, yet enhancing their architecture and functionality to improve therapeutic efficacy poses marked challenges. Here, inspired by the antioxidant strategy of blueberries and the wet adhesive mechanism of clingfish, we construct hierarchical and multifunctional microneedles. These microneedles possess both wet adhesive and antioxidant properties, making them highly effective for ocular wound healing. Constructed using polyacrylic acid-N-hydroxysuccinimide-based hydrogel with hexagonal structures, these generated microneedles ensure strong adhesion in wet environments. Furthermore, by incorporating proanthocyanidins (pAc) into the tips, the microneedle is imparted with excellent competence to scavenge reactive oxygen species (ROS). In the rat model of ocular alkali burns, the designed microneedle not only exhibited robust adhesion and desirable antioxidant properties in the moist ocular environment but also facilitated sustained drug release and effective treatment. These results suggest that our bioinspired microneedles with multifunctional properties offer substantial advancement over conventional approaches, positioning them as promising candidates for versatile wound healing applications.