Iodine-doped carbon dots with inherent peroxidase catalytic activity for photocatalytic antibacterial and wound disinfection

A new type of nitrogen-iodine co-doped carbon dot (N/I-CD) was synthesized by a one-step hydrothermal method with a fluorescence quantum yield of 37%. The prepared N/I-CDs exhibit peroxidase-like activity, can catalyze bio-safety levels of H2O2 to generate hydroxyl radicals (center dot OH) under visible light and enhance the level of reactive oxygen species (ROS) in bacteria cells. All in vitro experiments showed that the designed system has strong photocatalytic antibacterial activity against both E. coli and S. aureus bacteria. The light-induced antibacterial function of N/I-CDs was evaluated under the conditions of changing other experimental parameters. When the visible light irradiation time was extended to 60 min, the antibacterial efficiency of N/I-CDs (0.21 mg center dot mL(-1)) against S. aureus and E. coli reached 100% in the presence of exogenous H2O2 (0.07 mM). More importantly, wound disinfection in vivo demonstrates the high antibacterial efficiency, low toxicity and application potential of good biocompatibility due to the nanozyme activity of N/I-CDs.

Automated summary

The synthesized N/I-CDs exhibit good fluorescence properties and peroxidase-like activity, catalyzing the generation of reactive oxygen species under visible light and showing strong photocatalytic antibacterial activity in vitro, achieving 100% antibacterial efficiency against Staphylococcus aureus and Escherichia coli in the presence of exogenous H2O2. In vivo wound disinfection experiments demonstrate the high antibacterial efficiency, low toxicity, and potential application of N/I-CDs due to their good biocompatibility and nanozyme activity.