Construction of Customizable Wrinkle-Patterned Hydrogel/Fibrous Membrane Composites for Wound Healing

Hydrogels featured with high water content are exploited as one of the most promising wound dressings for burn wounds. However, hydrogels suffer from poor stretchability and limited wound healing efficacy. Herein, a versatile strategy is developed to fabricate customizable wrinkle-patterned hydrogel/fibrous membrane (HFM) composites through modulating the spatial distribution of hydrogel modulus by virtue of mask-assisted photo-crosslinking, as well as adjusting the pre-stretching of the elastic substrate. Furthermore, the introduction of tannic acid (TA) provides abundant interactions between the hydrogel and the nanofibrous membrane, thus ensuring a strong interfacial adhesion. The synergistic effects of wrinkle-induced stress dissipation and TA-reinforced network contribute to superior mechanical performances, including large fracture elongation of >400%, high tensile strength of 1.2 MPa, and robust shape recovery ability. Moreover, the gradient immobilization of stromal-cell-derived factor 1α (SDF1α) is achieved, and the SDF1α immobilized dressing is capable of directing stem cell migration in vitro. Additionally, the in vivo study of deep second-degree burn wound repair in rats and RNA sequencing analysis demonstrate that SDF1α gradient immobilized HFM can reduce inflammation, leading to enhanced wound healing. Such a customizable wrinkled composite presents huge potential for burn wound repair and offers new horizons for the construction of desirable wrinkle pattern.