Levofloxacin-based carbon dots to enhance antibacterial activities and combat antibiotic resistance

The emergence of antibiotic resistance in bacteria is an urgent issue, especially in treating infectious diseases. Nowadays, bacterial infections draw great attention to research and develop new antibacterial agents, while less attention was paid to trade the old for the new. Levofloxacin, as one of quinolones, has broad-spectrum and strong antibacterial effect. However, the clinical employment of levofloxacin is limited for drug resistance. Herein, levofloxacin-based carbon dots (LCDs) with enhanced antibacterial activities and low drug resistance were synthesized via a simple one-pot hydrothermal method. Results indicated that LCDs possessed effective antibacterial property by preserving the active groups of the levofloxacin. LCDs provided the dual-antibacterial mode to collapse bacteria based on the positive surface charge and the production of reactive oxygen species simultaneously. In addition, the in vitro and in vivo experiments suggested that the LCDs displayed excellent antibacterial activity and biocompatibility, as reflected by the improved curative effect in animal infected models and selectively eliminating bacteria over mammalian cells and tissues. Consequently, this work highlights the potential application of the above-mentioned LCDs with improved broad-spectrum antibacterial activity and resistance to drug resistance as an antibacterial nanomaterial on the field of antibacterial medicine.