Light-triggered release of nitric oxide from chitosan-based cationic hydrogels for promoting infected wounds healing.

Infected wounds are highly susceptible to bacterial contamination, which not only delays the healing process but also leads to a range of complications. NO is one of the most widely used gas molecules in wound treatment strategies due to its potent antibacterial and healing-promoting properties. However, excessive NO in infected wounds can damage cellular components and exacerbate inflammation. Therefore, precise control of NO dosage and targeted delivery to the wound site are crucial for effective treatment. Herein, a cationic hydrogel was constructed using modified guar gum and polyvinyl alcohol to enhance antibacterial effects, with guanidine-modified chitosan (Met-CS) and the photosensitizer sodium copper chlorophyllin (SCC) incorporated to create a light-triggered NO release system. Both in vitro and in vivo experiments confirmed that the proposed hydrogel exhibits excellent antibacterial performance, anti-inflammatory effects, and wound healing capabilities, demonstrating its potential for precise therapeutic applications.