Both centripetal current and shrinkage triggered by NIR to guide infected wound closure

Abstract

Exogenous directed electrical stimulation (ES) has a positive effect on accelerating wound closure. However, current ES relies on wires and bulky external power sources, limiting its application in daily treatments. Thermoelectric hydrogel, which can convert low-grade heat into electric energy, has great potential for self-power supply, facing the challenge that current generated by a small temperature difference cannot meet the demand for repairing endogenous electric field. In this study, a photo-thermoelectric supramolecular thermosensitive hydrogel (SPTP-Cu) is synthesized, which can achieve a centripetal current, controllable contraction, and effectuate antibacterial cooperation to accelerate wound closure and re-epithelization through a single NIR input on the hydrogel center. In addition, SPTP-Cu hydrogel demonstrates remarkable injectability, fast self-healing, a strong antioxidant, and rapid hemostatic without residual. In the rat infection wound repair experiment, SPTP-Cu + NIR treatment can effectively promote angiogenesis, collagen deposition, and re-epithelialization, achieving tissue remodeling in a short period (12 days). We deem photo-thermoelectric supramolecular thermosensitive hydrogel can be a promising candidate for multifunctional wound dressings for infectious wound treatment.