Degradable Carbon Dots with Broad-Spectrum Antibacterial Activity.

The infection of bacteria and fungus is one of the most challenging global threats to human health. With the recent advancement in nanoscience and nanotechnology, much progress has been achieved in the development of antimicrobial nanomedicine; however, these nanomaterial-based antibacterial agents still suffer from potential biological toxicity, poor degradation, and various secondary pollution. Here, we demonstrate the fabrication of low-toxic and degradable carbon dots (CDs) from vitamin C by one-step electrochemical method. These newly generated CDs display a strong broad-spectrum antibacterial activity and antifungal activity even at low concentrations, as they destroy the bacterial walls during the diffusive entrance, perturb secondary structures of DNA/RNAs of bacteria and fungus, and inhibit important gene expressions to finally kill the bacteria and fungus. We also show that these well-characterized CDs can be completely degraded into CO2, CO and H2O under visible light in air (or at very mild temperature, about 37 °C).