A multifunctional bilayer hydrogel patch with photothermal-driven directional contraction and bioregulation for enhanced wound healing

作者：Pengchao Ma, Yihao Liu, Chun‐Yi Yang, Jiakuan Yang, Zheng Cao, Bowen Ren, Zhi He, Bolin An, Chenyu Huang, Jianheng Liu, Xiumei Wang · 发表于：Materials Today · 年份：2025 · DOI：10.1016/j.mattod.2025.10.001 · 被引用次数：6 · 研究领域：Electrospun Nanofibers in Biomedical Applications、Hydrogels: synthesis, properties, applications、Wound Healing and Treatments

Tension-induced stress concentration, particularly perpendicular to Langer lines, exacerbates wound expansion, inflammation, delayed healing, and scarring. Therefore, directional tension reduction represents a promising strategy to enhance wound repair. We designed a multifunctional bilayer hydrogel patch (DCTH/PH) that integrates directional tension reduction with bioregulatory properties to synergistically enhance wound healing. The inner layer, a photothermal-responsive hydrogel (PH), formed by a dynamic network of oxidized sodium alginate and carboxymethyl chitosan, enabling wound contour adaptation. Photothermal nanozyme (PNZ) consisting of tannic acid and Ce 4+ are embedded within PH to provide bioregulatory and photothermal capabilities. The outer layer, a directional contraction thermo-responsive hydrogel (DCTH), employs an anisotropic poly(N-isopropylacrylamide)/alginate matrix engineered via tunable stretching and fixation to achieve directional temperature-responsive contraction. Under near-infrared irradiation, PNZ trigger a rapid temperature increase, inducing DCTH self-contraction. The released PNZ further exhibit inflammation reducing effects and promotes angiogenesis, enabling multi-regulatory functionality. In an incision model, DCTH/PH induced anisotropic contraction (up to 27.6 kPa), reducing mechanical stress by 90.3 % to maintain a low-tension microenvironment. Simultaneously, it promoted skin regeneration by enhancing angiogenesis and modulating inflamma...