Copper-rich multifunctional Prussian blue nanozymes for infected wound healing.

The healing process of infected wounds was limited by bacterial infection, excessive reactive oxygen species (ROS) accumulation, and tissue hypoxia. In order to alleviate the above situations, herein, a copper-rich multifunctional ultra-small Prussian blue nanozymes (HPP@Cu NZs) was constructed for infected wound synergistic treatment. Firstly, hyaluronic acid was modified by branched polyethyleneimine which could form a complex with copper ions, to construct copper-rich Prussian blue nanozymes. Secondly, the HPP@Cu NZs have a uniform ultra-small nano size and excellent photothermal response performance, exhibition of multifunctional enzymatic activity and anti-inflammatory properties. Finally, the slow release of copper ions in the HPP@Cu NZs could effectively promote the formation of new blood vessels, thus giving it multifunctional properties. In vitro and in vivo experiments showed that it not only could effectively inhibit and kill bacteria under 808 nm near-infrared laser but also could remove excessive ROS, regulate oxygen levels, and anti-inflammation. More importantly, the release of copper ions could synergistically promote the healing of infected wounds as well as good biocompatibility. Overall, our studies provide a multifunctional strategy for infected wounds with synergistic treatment based on carrier construction.