As nanoscale luminescent semiconductors with a wide-ranging access to many precursors, carbon dots (CDs) represent an extremely biofriendly structure with easy and low-cost preparation methods. In the meantime, antibiotic resistance is currently a global challenge needing utmost attention for health. In the current study, luminescent CDs were prepared using the solvothermal treatment of citrus tangerine peel-extract. With a bluish excitation-dependent emission, the amorphous CDs formed by C, O, Ca, and K. Biomass-based CDs showed a reliable antimicrobial activity against various gram-positive and -negative bacteria. The antibacterial effects of CDs were evaluated and compared with some antibiotics, that routinely use for treatment of infection caused by these bacteria. Our results showed that the antibacterial effects of CDs were more effective than amikacin, gentamycin, ceftazidime in most of the bacterial culture. It revealed somehow identical properties to that of imipenem, while a little bit worse bactericidal activity compared to ciprofloxacin and Cefixime was obtained. In conclusion; CDs can be an effective alternative for antibiotics, although their side effects in the body have to be investigated.
