Co4N Nanozymes Self-Supplied with H2O2 for Broad-Spectrum Antibacterial Activity against Escherichia coli and Staphylococcus aureus

Highly pathogenic bacterial infections are a major threat to human health, and the resulting drug resistance is beginning to pose a major clinical threat. To combat multidrug-resistant bacterial infections, there is an urgent need to develop antimicrobial drugs that are highly effective, environmentally friendly, and able to prevent the emergence of bacterial resistance. In this paper, Co₄N nanozymes were successfully synthesized by pyrolysis of a presynthesized Co-containing metal organic framework (Co-MOF). Its peroxide and lactate oxidase activity and antimicrobial properties were investigated. Without the addition of exogenous H₂O₂, the nanozymes can initially generate H₂O₂ by catalyzing lactic acid and then produce highly active •OH from H₂O₂. This approach overcomes the obstacle of insufficient H₂O₂ to achieve a satisfactory antimicrobial effect. Furthermore, the local high temperature generated by Co₄N under 808 nm laser irradiation further enhanced the antibacterial effect. These results showed that the nanozyme possesses broad-spectrum antimicrobial activity against Escherichia coli and Staphylococcus aureus, with an inhibition rate as high as 99% within 2 h. Meanwhile, the enzyme has good biocompatibility, paving a way for the application of MOF materials in biomedical fields.