富镉离子CdS量子点电化学发光法检测L-半胱氨酸  

Ultrasensitive Determination of L-Cysteine Based on Its Enhancement to Electrochemiluminescence of Cd S Quantum Dots with Cd^(2+) Rich Surface

作　　者：姜瑞[1] 杨学梅[1] 王明丽[1] 杨敏丽[1] 

机构地区：[1]上海师范大学生命与环境科学学院,上海200234

出　　处：《分析化学》2017年第3期409-415,共7页Chinese Journal of Analytical Chemistry

摘　　要：采用一锅法,通过控制镉硫比合成了表面富镉离子的硫化镉量子点,利用L-半胱氨酸可与量子点表面Cd^(2+)结合,使量子点表面钝化,从而增强其电化学发光信号的性质,实现了对L-半胱氨酸的选择性检测。对合成的量子点进行了表征,优化了检测条件。在优化的条件下,L-半胱氨酸在5.0×10^(-9)~1.0×10^(-5)mol/L浓度范围内与ECL信号呈良好的线性关系,检出限为1.2×10^(-9)mol/L(S/N=3)。本方法对L-半胱氨酸具有良好的选择性,用于实际样品中L-半胱氨酸的测定,结果令人满意。A novel electrochemiluminescence （ECL） method for the determination of L-cysteine （L-Cys） was established. Water-soluble CdS quantum dots （QDs） with Cd2＋rich surface were synthesized via a controllable one-poe approach. The mercapto group in L-cysteine molecule can specifically interact with excessive Cd2＋on the surface of CdS QDs, resulting in enhancement of ECL intensity of the CdS QDs, which can be used for the detection of L-Cys. Under the optimal experimental conditions, the enhancement of ECL intensity was linear with the concentration of L-Cys in the range of 5.0×10^-9-1.0×10-5 mol/L. The limit detection of （S/N=3） was 1.2×10^-9 mol/L. In comparison with other methods for detecting L-Cys, this method is more simple and selective, and can be applied to detect L-Cys in real sample with satisfactory results.

关 键 词：电化学发光 表面富镉离子硫化镉量子点 L-半胱氨酸 

分 类 号：O657.3[理学—分析化学]