Abstract: Berberine hydrochloride carbon dots (BCDs) were synthesized by a one-step hydrothermal method using berberine hydrochloride (Ber) as the raw material. The morphology, structure, and optical properties of BCDs were characterized by transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis) spectroscopy, and fluorescence spectroscopy. The antibacterial properties were studied by bacterial growth curves and spread plate method using foodborne Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) as model strains. The results showed that BCDs have a small particle size, good dispersion, and fluorescence properties. BCDs have a stronger antibacterial ability than the raw materials, and the antibacterial effect against Gram-positive bacteria was better than that against Gram-negative bacteria. When BCDs concentration was $ 40 \mu g/mL $ and $ 320 \mu g/mL $, respectively, the inhibition effect against S. aureus and E. coli was the best.
Keywords: nanotechnology; antibacterial; carbon dots; berberine hydrochloride; foodborne