A thermogalvanic cell dressing for smart wound monitoring and accelerated healing

Current smart dressings with wound monitoring and electrical stimulation capabilities rely on flexible electronics comprising various sensors and external power sources. Despite increasing efforts to integrate all these components onto flexible, breathable and biocompatible substrates, realizing a zero-power electrical stimulation without compromising the clinical applicability remains challenging. Here we report a solution that harnesses the temperature gradient between the wound and dressing to generate an electric stimulus that provides active wound healing management. This was achieved by a thermogalvanic cell (TGC) dressing composed of Fe²⁺/Fe³⁺ cross-linked alginate hydrogel reinforced by nanofibres. The TGC dressing exhibits biocompatibility, antibacterial performance, easy re-shaping and moisture permeability. Moreover, the TGC dressing generates an exogenous electric field, promoting the spontaneous acceleration of wound healing. We additionally integrate a sensing system that can monitor respiration rate. In the large porcine wound model, the wound healing rate of a TGC-bandaged group is improved by about 20.6% on day 14 compared with an untreated group. Our wireless wound monitoring system may facilitate real-time monitoring of common wound models at different wound development stages.