Integrated photo-inspired antibacterial polyvinyl alcohol/carboxymethyl cellulose hydrogel dressings for pH real-time monitoring and accelerated wound healing.

Recurrent infection of chronic wounds remains a major clinical challenge. Recently, the hydrogel antibacterial materials have attracted extensive attention for preventing infection in wound healing. In this study, a hybrid hydrogel made of polyvinyl alcohol - iodine (PAI), sodium carboxymethyl cellulose (CMC), and carbamino quantum dot (CQDs) was prepared by the cross-linking of hydrogen bonds, named as polyvinyl alcohol‑iodine/sodium carboxymethyl cellulose/carbon quantum dots (PAI/CMC/CQDs). The composite hydrogels exhibited the outstanding photothermal conversion efficiency with near infrared (NIR) light irradiation, and the high antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Meanwhile, the elevated temperature of the composite hydrogels up to ~45 °C was able to stimulate the migration of epidermal cell to accelerate skin repair. Given that PAI and CQDs could respond to different pH values (5-8), the real-time would pH information was provided by the visible light and fluorescent light dual monitoring system by naked eye. Moreover, the visible-fluorescent images could be collected and transformed into RGB signals to quantify the would pH levels, avoiding secondary injuries caused by frequent dressing changes. PAI/CMC/CQDs was demonstrated the significant therapeutic effect on chronic wounds by eliminating bacterial infections and promoting skin repair under the smart RGB monitoring system.