Facile synthesis of nanoparticles-stacked CoO nanoflakes with catalase-like activity for accelerating wound healing.

Delayed wound healing caused by excessive reactive oxygen species (ROS) remains a considerable challenge. In recent years, metal oxide nanozymes have gained significant attention in biomedical research. However, a comprehensive investigation of CoO-based nanozymes for enhancing wound healing and tissue regeneration is lacking. This study focuses on developing a facile synthesis method to produce high-stability and cost-effective CoO nanoflakes (NFs) with promising catalase (CAT)-like activity to regulate the oxidative microenvironment and accelerate wound healing. The closely arranged CoO nanoparticles (NPs) within the NFs structure result in a significantly larger surface area, thereby amplifying the enzymatic activity compared to commercially available CoO NPs. Under physiological conditions, it was observed that CoO NFs efficiently break down hydrogen peroxide (HO) without generating harmful radicals (·OH). Moreover, they exhibit excellent compatibility with various cells involved in wound healing, promoting fibroblast growth and protecting cells from oxidative stress. In a rat model, CoO NFs facilitate both the hemostatic and proliferative phases of wound healing, consequently accelerating the process. Overall, the promising results of CoO NFs highlight their potential in promoting wound healing and tissue regeneration.