Engineering Injectable Coassembled Hydrogel by Photothermal Driven Chitosan-Stabilized MoS Nanosheets for Infected Wound Healing.

The application of enzyme-like molybdenum disulfide (MoS) in tissue repair was confronted with stable dispersion, solubilization, and biotoxicity. Here, the injectable self-healing hydrogel was successfully designed using a step-by-step coassembly of chitosan and MoS. Polyphenolic chitosan as a "structural stabilizer" of MoS nanosheets reconstructed well-dispersed MoS@CSH nanosheets, which improved the biocompatibility of traditional MoS, and strengthened its photothermal conversion and enzyme-like activities, guaranteeing highly efficient radical scavenging and antimicrobial properties. Furthermore, the polyphenol chitosan was employed again as a "molecular cross-linking agent" to form the injectable NIR-responsive MoS@CSH hydrogel by accelerating hydrogen-bond interaction among chitosan and the multicross-linking reaction among polyphenols. The rapid self-healing ability was conducive to wound closure and dynamic adaptability. An experimental study on infected wound healing demonstrated that MoS@CSH hydrogel could substantially eradicate bacteria and accelerate the angiogenesis of infected wounds. The photothermal-driven coassembly of MoS and polycation provided an alternative strategy for infected wound healing.