Near-infrared carbon nanodots for effective identification and inactivation of Gram-positive bacteria

An unacceptable increase in antibacterial resistance has arisen due to the abuse of multiple classes of broad-spectrum antibiotics. Therefore, it is significant to develop new antibacterial agents, especially those that can accurately identify and kill specific bacteria. Herein, we demonstrate a kind of perilla-derived carbon nanodots (CNDs), integrating intrinsic advantages of luminescence and photodynamic, providing the opportunity to accurately identify and kill specific bacteria. The CNDs have an exotic-doped and π-conjugated core, vitalizing them near-infrared (NIR) absorption and emission properties with photoluminescence quantum yield of 21.1%; hydrophobic chains onto the surface of the CNDs make them to selectively stain Gram-positive bacteria by insertion into their membranes. Due to the strong absorption in NIR region, reactive oxygen species are in situ generated by the CNDs onto bacterial membranes under 660 nm irradiation, and 99.99% inactivation efficiency against Gram-positive bacteria within 5 min can be achieved. In vivo results demonstrate that the CNDs with photodynamic antibacterial property can eliminate the inflammation of the area affected by methicillin-resistant Staphylococcus aureus (MRSA), and enabling the wound to be cured quickly.