高等学校化学学报 ›› 2020, Vol. 41 ›› Issue (2): 268-276.doi: 10.7503/cjcu20190448

• 分析化学 • 上一篇    下一篇

基于单(6-巯基-6-去氧)-β-环糊精修饰金电极对L-半胱氨酸的快速灵敏检测

彭与煜,王煜,于鑫垚,曾巨澜,肖忠良,曹忠()   

  1. 长沙理工大学化学与生物工程学院, 电力与交通材料保护湖南省重点实验室, 长沙 410114
  • 收稿日期:2019-08-09 出版日期:2020-02-10 发布日期:2019-11-14
  • 通讯作者: 曹忠 E-mail:zhongcao2004@163.com
  • 基金资助:
    国家自然科学基金(31527803);国家自然科学基金(21545010);湖南省自然科学基金资助(2017JJ1026)

Rapid and Sensitive Detection of L-Cysteine Based on Mono(6-mercapto-6-deoxy)-β-cyclodextrin Modified Gold Electrode

PENG Yuyu,WANG Yu,YU Xinyao,ZENG Julan,XIAO Zhongliang,CAO Zhong()   

  1. Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha 410114, China
  • Received:2019-08-09 Online:2020-02-10 Published:2019-11-14
  • Contact: Zhong CAO E-mail:zhongcao2004@163.com
  • Supported by:
    ? Supported by the National Natural Science Foundation of China(31527803);Supported by the National Natural Science Foundation of China(21545010);the Natural Science Foundation of Hunan Province, China(2017JJ1026)

摘要:

将单(6-巯基-6-去氧)-β-环糊精(HS-β-CD)通过金硫键自组装在金电极(GE)表面, 构建了一种简单、 快速、 灵敏的超分子识别L-半胱氨酸(L-Cys)的电位型电化学传感器. 通过循环伏安法和交流阻抗法研究了膜表面的电化学行为; 通过扫描电子显微镜(SEM)和X射线光电子能谱(XPS)表征了电极表面的膜组装效果, 其作用机制是固定在金电极表面的HS-β-CD空穴可通过分子间作用力吸附结合带负电的L-Cys, 使电极表面的膜电位发生改变, 导致对L-Cys的超分子选择性识别作用, 从而实现对L-Cys的定量分析. 在优化的实验条件下, 该电极在pH=6.0的磷酸盐缓冲溶液中对L-Cys有良好的电位响应性能, 线性范围为1.0×10 -7~1.0×10 -4 mol/L, 斜率为(-65.29±1.0) mV/pc(25 ℃), 检测下限达到6.0×10 -8 mol/L; 电极响应速度快、 稳定性和重现性好、 抗干扰能力强. 将该电极用于实际猪血清和猪尿液样品中L-Cys含量的测定, 回收率为95.0%~104.7%, 表明该新型电极在生命科学等领域具有良好的应用前景.

关键词: L-半胱氨酸, 单(6-巯基-6-去氧)-β-环糊精, 自组装膜, 超分子识别, 电位传感

Abstract:

A simple, rapid and sensitive L-cysteine(L-Cys)potentiometric electrochemical sensor was constructed by using mono(6-mercapto-6-deoxy)-β-cyclodextrin(HS-β-CD) self-assembled on surface of gold electrode(GE) via gold-sulfur bond. The electrochemical behavior of the electrode membrane surface was investigated through cyclic voltammetry and impedance analysis. Scanning electron microscopy and X-ray photoelectron spectroscopy have also demonstrated the film assembly effectiveness of the electrode. And the interaction mechanism of the electrode was that the cyclodextrin cavity of HS-β-CD immobilized on the gold surface can adsorb and bind electronegative L-Cys through intermolecular force, resulting in change of the membrane potential on the electrode surface and further realization of supramolecular selective recognition of L-Cys. In the optimal condition, the modified electrode had good potential response feature to L-Cys in PBS(pH=6.0) with a linear range of 1.0×10 -7—1.0×10 -4 mol/L and a slope of (-65.29±1.0) mV/pc(25 ℃). The detection limit can reach 6.0×10 -8 mol/L. The electrode responded quickly, which had high stability, good reproducibility, and strong anti-interference ability. The electrode can be well used for the determination of L-Cys in actual pig serum and pig urine samples with recovery rate of 95.0%—104.7%, showing its important application prospects in life science fields.

Key words: L-Cysteine, Mono(6-mercapto-6-deoxy)-β-cyclodextrin, Self-assembled monolayer, Supramole-cular recognition, Potential sensor