Conductive adhesive self-healing nanocomposite hydrogel wound dressing for photothermal therapy of infected full-thickness skin wounds

Bacteria-infected wounds and antibiotics abuse have become significant burdens to patients and medical systems. Thus, designing a non-antibiotic-dependent multifunctional wound dressing for treating bacteria-infected wounds is urgently desired. Herein, a series of conductive self-healing and adhesive nanocomposite hydrogels with a remarkable photothermal antibacterial property based on N-carboxyethyl chitosan (CEC) and benzaldehyde-terminated Pluronic F127/carbon nanotubes (PF127/CNT) were developed, and their great potential as agents for photothermal therapy (PTT) of infected wounds was demonstrated in vivo. The hydrogels exhibited a suitable gelation time, stable mechanical properties, hemostatic properties, high water absorbency, and good biodegradability. After loading the antibiotic moxifloxacin hydrochloride, the hydrogels showed a pH-responsive release profile and good antibacterial activity. The tissue adhesive property of the hydrogels allowed them to have a good hemostatic effect in a mouse liver trauma model, mouse liver incision model, and mouse tale amputation model. The addition of CNTs endowed the hydrogel with in vitro/in vivo photothermal antimicrobial activity and good conductivity. An in vivo experiment in a mouse full-thickness skin wound-infected model indicated that the hydrogels had an excellent treatment effect leading to significantly enhanced wound closure healing, collagen deposition, and angiogenesis. In summary, these conductive photothermal self-healing nanocomposite hydrogels as multifunctional wound dressing exhibit great potential for the treatment of infected wounds.