Dual-Template Engineered Low-Tortuosity Hydrogels with Gradient Microchannels for On-Demand Management of Refractory Wounds.

Chronic refractory wounds present a significant clinical challenge due to the vicious cycle of excessive exudate and bacterial infections. Herein, we develop a smart hydrogel dressing via a dual-template strategy that creates a low-tortuosity structure with gradient microchannels. Compared with the random porous hydrogel, the optimized structure accelerates the absorption rate of viscous liquid by ∼17 times. Crucially, the hydrogel incorporates a thermal feedback loop: the increase in wound temperature caused by infection stimulates the hydrogel to rapidly release antibacterial agents, thereby resolving the infection and effectively cooling the wound; after inflammation suppression, the residual exudate and antibacterial agents are actively reabsorbed to achieve on-demand treatment. In an infectious burn model, this dressing outperforms commercial dressing 3 M Tegaderm by downregulating inflammatory cytokines, enhancing collagen regeneration, and accelerating angiogenesis. This study provides a novel and universal design strategy for the next generation of functional dressings for refractory wounds.