氮掺杂碳量子点荧光探针快速检测山梨酸钾

山梨酸钾属于酸性食品防腐剂,能有效地抑制霉菌、酵母菌和好氧性细菌的活性,延长食品的保存时间,并保持食品原有的风味.本研究通过一步水热法合成了水溶性良好的荧光氮掺杂碳量子点（NCQDs）,基于山梨酸钾能有效地猝灭NCQDs而构建了快速检测山梨酸钾的荧光探针.在最佳实验条件下,山梨酸钾浓度在3.0×10^-5～1.0×10^-4mol/L和1.0×10^-7～3.0×10^-5mol/L范围内与NCQDs荧光猝灭强度呈现良好的线性关系,检出限为9.5×10^-8mol/L.我们已将其用于苏打水及白醋中山梨酸钾含量的测定,回收率分别为98.25%～102.7%和98.33%～101.8%.

Rapid detection of potassium sorbate by nitrogen-doped carbon quantum dots fluorescence probe

Potassium sorbate is an acidic food preservative, which can effectively inhibit the activity of mold, yeast and aerobic bacteria, prolong the storage time of food, and maintain the original flavor of food. In this study, fluorescence nitrogen doped carbon quantum dots (NCQDs) with good water solubility was synthesized by one-step hydrothermal method. Based on the effective quenching of NCQDs by potassium sorbate, a fluorescence probe for rapid detection of potassium sorbate was constructed. Under the optimal experimental conditions, the concentration of potassium sorbate showed a good linear relationship with the fluorescence quenching intensity of NCQDs in the range of 3.0×10-5~ 1.0×10-4 mol/L and 1.0×10-7~3.0×10-5 mol/L, and the detection limit was 9.5×10-8 mol/L. It has been used for the determination of potassium sorbate in soda water and white vinegar with the recoveries of 98.25%~102.7% and 98.33%~101.8%.