Construction of photo-induced zinc-doped carbon dots based on drug-resistant bactericides and their application for local treatment

In this project, we propose a highly effective photosensitizer that breaks through drug-resistant bacterial infections with zinc-doped carbon dots. By passing through the membrane of drug-resistant bacteria, the photosensitizers produce ROS in bacteria under the action of blue light to directly kill bacteria, so as to realize the antibacterial local treatment of drug-resistant bacteria. The experiment firstly uses an efficient one-step hydrothermal method to prepare zinc-doped red-light CDs as photosensitizers, in which zinc metal was doped to improve the optical properties of the CDs. Then we try first to use EDTA as a second-step attenuator for preparing CDs to obtain photosensitizers with high-efficiency and low toxicity. In vitro cytotoxicity tests, bacterial effect tests, and in vivo animal experiments have also demonstrated that this antibacterial method has great potential for clinical translation, with a bactericidal efficiency of up to 90%. More notably, we used this antibacterial regimen seven times repeatedly to simulate the bacterial resistance process, with a bactericidal efficiency of up to 90% every time. The result indicated that S. aureus did not develop resistance to our method, showing that our method has the potential to break through drug-resistant bacterial infections as an alternative to antibiotic candidates.