Synthesis of Copper–nitrogen Codoped Carbon Quantum Dots Using Frangipani as a Carbon Source and Application of Metronidazole Determination

Abstract High-fluorescence Cu/N codoped carbon quantum dots (Cu/NCQDs) were prepared by a one-step hydrothermal method using frangipani as the carbon source and copper acetate as the copper source. The Cu/NCQDs exhibited high-intensity, stable blue fluorescence that is independent of the excitation wavelength. Since metronidazole can effectively quench the fluorescence intensity of Cu/NCQDs, a metronidazole fluorescence-detection method using Cu/NCQDs as the fluorescence probe was developed, and the quenching mechanism was studied.The method has the advantages of simplicity, speed, and low cost. Besides,it has a wider linear range and detection limit. Further, the metronidazole content in actual samples was determined by this method, with good results.