Cocktail effect of ionic patch driven by triboelectric nanogenerator for diabetic wound healing

There is increasing evidence shows that either electrical stimulation (ES) or metal ion is an effective way to accelerate ulcerative wound healing. However, less attention is paid to investigating the synergistic effect between them. Herein, we explore the combined effects of ES and multiple mental ions on diabetic wound healing assisted by a triboelectric nanogenerator (TENG). Firstly, the novel Eggshell@CuFe2O4 nanocomposites (NCs) are prepared, which show unique structure and intrinsic antimicrobial properties. Subsequently, the as-prepared nanocomposites are embedded in oxidized starch hydrogel to form a multifunctional composite gel, which is further assembled into a wearable ionic triboelectric nanogenerator (iTENG) patch with polydimethylsiloxane (PDMS). It can convert the mechanical energy produced by a human body motion to electric energy and mediate the sequential release of metal ions (Fe2+/Ca2+/Cu2+), thereby resulting in the "cocktail effect" on impaired tissue. Under their effects, a satisfying healing result in diabetic mouse is identified, which can effectively accelerate wound healing process by relieving inflammation, promoting angiogenesis and collagen deposition. The work puts forward the cocktail effect of electric simulation coupled with the multiple metal ions, and opens up a new perspective in designing iTENG patch towards repair of hard-to-heal wounds.