Sprayable Hydrogel Encapsulating Curcumin Micelles and Copper-Doped Polydopamine with Antimicrobial and Immunoregulation for Efficient Infected Wound Healing and Flexible Sensing

Abstract Infected wounds pose a significant challenge in clinical practice. Their persistent inflammatory response and bacterial colonization not only severely impede the healing process but may also lead to life-threatening complications. It is essential to develop effective strategies for improving the healing of infected wounds. Therefore, a sprayable hydrogel was assembled from phenylboronic acid-functionalized chitosan (CS-BA) and poly(vinyl alcohol) (PVA). The drug-loading micelles were fabricated by self-assembly of amphiphilic ε-polylysine-octenyl succinic anhydride (EPL-OSA), encapsulating immune-modulating curcumin (MC). The photothermal reagent, copper-doped polydopamine nanoparticles (PDA@Cu), was prepared by an in situ reduction method. The sprayable CS-BA/PVA hydrogel loaded MC and PDA@Cu rapidly formed within 30 s and exhibited synergistic antimicrobial activity from EPL and an excellent photothermal antimicrobial effect from PDA@Cu. The curcumin released from the micelles suppressed pro-inflammatory factor expression, enhanced anti-inflammatory factor expression, and facilitated M2 macrophage polarization. The synergistic antimicrobial and immunomodulatory effects accelerated the healing of infected wounds. Meanwhile, the hydrogel shows electrical conductivity and can be used as a flexible sensor to achieve flexible sensing.