One-Step and One-Precursor Hydrothermal Synthesis of Carbon Dots with Superior Antibacterial Activity

Abstract

Discovering efficient antibacterial materials is crucial in the area of increasing drug resistance. Herein, we synthesized carbon dots (C-dots) with superior antibacterial activity through a simple one-step hydrothermal method. In this method, <i>p</i>-phenylenediamine serves as not only the carbon source but also the origin for the functional group anchored on the obtained C-dots. The antibacterial activity of the obtained C-dots was tested against <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>. The minimum bactericidal concentrations of the synthesized C-dots against <i>S. aureus</i> and <i>E. coli</i> were 2 and 30 μg/mL, respectively, which are lower than that of previously reported C-dots. The antibacterial mechanism was investigated, and the results indicated that a large number of -NH₃⁺ groups on the C-dots' surface enhanced their antibacterial activity. Besides, the C-dots exhibited negligible cytotoxicity.