CdTe量子点荧光猝灭法测定尼群地平的研究

Studies on Fluorescence Quenching Method for the Determination of Nitrendipine with CdTe Quantum Dots

以L-半胱氨酸为稳定剂,在水溶液中合成了CdTe量子点.以该量子点为荧光探针,基于荧光猝灭法对尼群地平进行了定量检测.考察了缓冲体系、缓冲液浓度、缓冲液pH值、反应时间、量子点浓度等多种因素的影响,并对反应机理进行了初步的探讨.在0.03 mol/L、pH值为5.78的Tris-HCl缓冲液中,当量子点浓度为5.72×10^-4mol/L、反应时间为10 min时,该方法的线性范围为0.38-77μg/mL,检出限为0.28μg/mL.该方法已成功用于药片中尼群地平的测定,与中国药典中的标准方法比较,结果满意.

CdTe quantum dots were synthesized in aqueous solution with L-cysteine acid as the stabilizer.A new approach was developed for the sensitive and selective determination of nitrendipine with quantum dots as fluorescence probes.Different influencing factors were studied,including the concentration and pH of buffer,reacting time and quantum dots concentration,moreover,an initial study of the reaction mechanism was discussed.In 0.03 mol/L Tris-HCl with pH 5.78,when the concentration of quantum dots was 5.72×10^-4 mol/L and the reacting time was 10 minutes,the relative fluorescence intensity decreased linearly with the nitrendipine＇ concentration in the range of 0.38 to 61.6 μg/mL.The detection limit was 0.28 μg/mL.The pro-posed method has been applied to the analysis of nitrendipine in tablet successfully with satisfact ory results in comparison with the standard method in Pharmacopoeia of PR China.