Electrogenerated copper selenide with positive charge to efficiently capture and combat drug-resistant bacteria for wound healing

Limited by the effective radius of metal ion release, higher concentrations of antibacterial agents are usually required to achieve satisfactory efficacy. Unfortunately, the potential cytotoxicity of metal ions limits the administered dose, which greatly hinders the widespread use of metal antibacterial agents. In this work, we used a convenient electrochemical method to prepare electropositive copper selenide (CuSe) nanosheets gathered from the cathode. Under physiological conditions, trace amounts of electrolytic CuSe (E-CuSe, 1 μg mL-1) could electrostatically bind to bacterial membranes and almost completely kill three resistant bacteria models (106 colony forming unit (CFU) mL-1). The extremely low effective dose of E-CuSe reaches a new benchmark in comparison with copper-based nanomaterials in other related studies. In addition, due to the reasonable coupling of selenium and copper, the as-prepared E-CuSe nanosheets exhibit lower cytotoxicity compared to copper oxide. As expected, the E-CuSe performed well in resistant bacteria-infected wound healing in rats, rapidly promoting wound tissue with a diameter of about 1 cm recovery within 7 days. Transcriptome analysis revealed the E-CuSe mainly acted on the membrane transport and DNA synthesis systems of bacterial cells. This work presents an efficient and in-depth paradigm for the scientific design and inactivation mechanism of metal antibacterial agents.