A photothermal antimicrobial, antioxidant hydrogel for healing of bacterial-infected wounds

Skin is an important barrier to protect the body from the external environment. Once damaged, the body becomes vulnerable to external bacterial attacks, which induce wound infection, and excessive accumulation of reactive oxygen species (ROS) at the wound site destroys fibroblasts and thus affects the wound healing process. Therefore, in this study, an OD-Gel-CuTA hydrogel dressing with near-infrared (NIR) photothermal antimicrobial properties was prepared using gelatin (Gel), oxidized dextran (ODex), and copper tannic acid nanosheets (CuTA). The composition and morphology of CuTA and the hydrogel were analyzed by XRD, FTIR and SEM. Additionally, the mechanical, antioxidant, NIR photothermal, and antimicrobial properties of the hydrogel were investigated with varying CuTA contents. The results showed that the addition of CuTA endowed the OD-Gel-CuTA hydrogel with good mechanical, antioxidant, and antimicrobial properties. Furthermore, the hydrogel promoted the healing of bacterial-infected wounds, which is potentially applicable to the treatment of bacterial wounds in combination with photothermal therapy.