掺氮碳量子点荧光光度法测定盐酸小檗碱

Fluorescence Spectrophotometric Determination of Berberine Hydrochloride with Nitrogen-Doped Carbon Quantum Dots

以抗坏血酸和乙二胺为原料,采用低温回流的方法合成了掺氮碳量子点(N-CDs),盐酸小檗碱对该N-CDs具有明显的荧光猝灭作用,据此提出了以N-CDs为荧光探针测定盐酸小檗碱的方法。在pH 7.40的三羟甲基氨基甲烷-HCl缓冲溶液中,盐酸小檗碱的浓度在5.0×10^(-7)~4.0×10^(-5) mol·L^(-1)内与N-CDs的荧光强度猝灭值呈线性关系,检出限(3s/k)为2.0×10^(-7) mol·L^(-1)。方法用于盐酸小檗碱药片的分析,加标回收率为99.2%,103%。通过荧光寿命和吸收光谱的变化以及温度对猝灭常数的影响,确定该N-CDs与盐酸小檗碱的作用机理为动态猝灭。

Nitrogen-doped carbon quantum dots（N-CDs）were synthesized by low temperature reflux method with ascorbic acid and ethylene diamine as raw materials.Berberine hydrochloride could quench the fluorescence of the N-CDs with specificity.Based on the fact,a method was proposed for berberine hydrochloride determination with N-CDs as a fluorescent probe.In Tris-HCl buffer solution of pH 7.40,linear relationship between quenching values of N-CDs fluorescence intensity and concentrations of berberine hydrochloride was kept in the range of 5.0×10-7-4.0×10-5 mol·L-1,with detection limit（3 s/k）of 2.0×10-7 mol·L-1.The proposed method was applied to the analysis of tablets of berberine hydrochloride,giving values of recovery of 99.2%,103%.The dynamic quenching between the N-CDs and berberine hydrochloride was proved by the changes of the fluorescence lifetime as well as the absorption spectrum and the effect of temperature on the quenching constants.