ROS-responsive robust hydrogels based on thiol-ene click chemistry for enhancing the healing of infected wounds

The development of novel antimicrobial wound healing dressings has become an urgent challenge with the increasing prevalence of drug-resistant bacterial infections. Herein, a reactive oxygen species (ROS) responsive robust hydrogel (THMA/TCMC-Gel@Cur) based on "thiol-ene" click chemistry was developed for infected wounds. The addition of curcumin-loaded gelatin nanoparticles (Gel@Cur) imparted excellent antibacterial and antioxidant properties to the THMA/TCMC-Gel@Cur hydrogel. Thiols and alkenes quickly formed thioether bonds through the "thiol-ene" click chemical reaction. The hydrophobic thioether bonds could be oxidized to hydrophilic sulfoxide bonds by ROS. THMA/TCMC-Gel@Cur hydrogel formed by "thiol-ene" click chemistry could respond to ROS and increase water molecules to enter the interior of the hydrogel by switching the hydrophilic to hydrophobic characteristics, thereby accelerating drug diffusion in the porous network. In vivo results showed that wounds treated with THMA/TCMC-Gel@Cur hydrogel had a wound closure ratio of 93.56% within 14 days, which was significantly higher than the other treatment groups. The THMA/TCMC-Gel@Cur hydrogel exhibited significant potential for clinical application, poised to enhance the quality of life for patients suffering from infectious dermatological disorders.