Dually‐Thermoresponsive Hydrogel with Shape Adaptability and Synergetic Bacterial Elimination in the Full Course of Wound Healing

Abstract Incomplete contact between a pre‐formed hydrogel and irregular wound limits the therapeutic effect of the dressing and increases the risk of infection; while great concerns have remained regarding the potential toxicity of the residual additives of chemical crosslinking for in situ forming hydrogels. Therefore, it is desirable to develop a self‐adaptive hydrogel in response to skin temperature with shape adaptability and efficient antibacterial properties to prevent microbial invasion. Herein, a dually‐thermoresponsive hydrogel composed of poly( N ‐isopropylacrylamide) (PNIPAm) and methacrylated κ ‐carrageenan (MA‐ κ ‐CA) is designed with compliance at physiological temperature to realize shape adaptability for completely covering irregular wounds. Furthermore, the hydrogel with near‐infrared (NIR)‐responsive polypyrrole‐polydopamine nanoparticles (PPy‐PDA NPs) and Zn 2+ ‐derived zeolitic imidazolate framework (ZIF‐8) can generate localized heat and gradually release Zn 2+ to realize safe, effective synergetic photothermal–chemical bactericidal capability. In addition, the release rate of Zn 2+ can be accelerated by NIR‐induced heating, and thus a more efficient sterilization can be provided to severely infected wounds. Therefore, the proposed hydrogel would serve as a promising wound dressing for the full course of wound healing, with the abilities of perfectly covering the wound and adapting to regenerating tissue, and controllable photothermal‐chemical antibacterial capability to reach high bactericidal efficiency and long‐term release of antibacterial agents.