Engineering ultrasound-activated piezoelectric hydrogels with antibacterial activity to promote wound healing

The development of nanocomposite hydrogel dressings with adhesion and superior mechanical and wound infection inhibition characteristics for wound repair and skin regeneration is urgently needed for clinical applications. In this study, the adhesive piezoelectric antibacterial hydrogels with high expansibility, degradability, and adjustable rheological properties were innovatively prepared by a simple assembly process with carboxymethyl chitosan (CMCS), tannic acid (TA), carbomer (CBM), and piezoelectric FeWO4 nanorods. As an exogenous mechanical wave, ultrasound can trigger the piezoelectric effect of FeWO4 and then effectively augment the generation of reactive oxygen species, exhibiting a superior antibacterial efficiency and preventing wound infection. In vitro and in vivo results have demonstrated that piezoelectric hydrogels can accelerate full-thickness skin wound healing in bacteria-infected mice by skin regeneration, inhibiting inflammatory response, increasing collagen deposition, and promoting angiogenesis. Such a discovery provides a representative paradigm for the rational design of piezoelectric hydrogel and effectively serves antibacterial and wound dressing fields.