Self-powered chitosan/graphene oxide hydrogel band-aids with bioadhesion for promoting infected wounds healing.

Typical anti-infection strategies, such as antibiotics and other antibacterial nanomaterials, are effective in preventing bacterial infections during the wound healing process. Additionally, electrical stimulation (ES) can also inhibit bacterial growth and facilitate skin wound repair. However, self-powered and therapeutic wearable devices combining antibacterial materials with ES are still lacking. In this research, a bio-adhesive band-aid with antibacterial activity and piezoelectric properties made up of a chitosan/graphene oxide (CSGO) hydrogel matrix and a piezoelectric nanogenerator (PENG) patch based on electrospun polyvinylidene difluoride (PVDF) nanofibers is developed for promoting infected wounds healing. Specifically, self-adhesive CSGO hydrogels help the band-aid closely adhere to the wound site, and PVDF nanofibers convert biokinetic energy into electricity to provide real-time ES. The in vitro antibacterial test demonstrates that >99 % of S. aureus and E. coli are killed by the treatment of CSGO hydrogel and ES. Remarkably, in the rat model of infected wounds, the assembled band-aid consisting of a PENG of 2.25 cm can promote angiogenesis, collagen deposition, and re-epithelialization, greatly accelerating infected wounds healing in 21 days. This study offers a simple and practicable method for the design of wearable bioelectronics, indicating a promising future in personalized healthcare and clinical treatment.