高等学校化学学报 ›› 2012, Vol. 33 ›› Issue (06): 1158.doi: 10.3969/j.issn.0251-0790.2012.06.007

• 分析化学 • 上一篇    下一篇

基于指示剂置换法利用紫外-可见光谱和比色检测水溶液中的半胱氨酸

李咏玲1,2, 张建刚2,3, 卫艳丽3, 程芳琴1   

  1. 1. 山西大学资源与环境工程研究所, 太原 030006;
    2. 山西农业大学文理学院, 太谷 030801;
    3. 山西大学化学化工学院, 太原 030006
  • 收稿日期:2012-01-13 出版日期:2012-06-10 发布日期:2012-06-10
  • 通讯作者: 程芳琴, 女, 博士, 教授, 博士生导师, 主要从事化学与环境工程研究. E-mail: cfangqin@sxu.edu.cn E-mail:ndlyl@126.com
  • 基金资助:

    中国博士后科学基金(批准号: 201104611)和山西省青年科技基金(批准号: 2010021010-2)资助.

Detection of Cysteine in Aqueous Solution Based on Indicator Displacement by Ultraviolet-Visible and Colorimetric Methods

LI Yong-Ling1,2, ZHANG Jian-Gang2,3, WEI Yan-Li3, CHENG Fang-Qin1   

  1. 1. Institute of Resource and Environment Engineering, Shanxi University, Taiyuan 030006, China;
    2. College of Arts and Science, Shanxi Agricultural University, Taigu 030801, China;
    3. College of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
  • Received:2012-01-13 Online:2012-06-10 Published:2012-06-10

摘要: 基于半胱氨酸(Cys)与二价铜离子的配位作用, 发展了一种在纯水溶液中以4-(2-吡啶偶氮)间苯二酚(PAR)为指示剂, 通过紫外-可见光谱定性定量检测半胱氨酸的方法. 研究发现, 在pH=7.0的含有PAR和二价铜离子(摩尔比为1: 1)的缓冲溶液中, 当加入半胱氨酸后, 由于配位竞争使PAR释放出来, 实现了对半胱氨酸的识别, 选择性研究结果表明, 其它氨基酸不干扰体系对半胱氨酸的测定. 通过紫外-可见光谱(UV-Vis)对识别过程进行了研究, 确定了Cu2+与PAR的配位比为1: 1, Cu2+与Cys的配位比为1: 3; 半胱氨酸的线性关系变化范围为0~240 μmol/L, ε=7519 L/(mol·cm), 线性相关系数为0.9982. 在检测过程中可观察到溶液颜色由桃红色变成了黄色.

关键词: 指示剂置换法, 二价铜离子, 4-(2-吡啶偶氮)间苯二酚, 半胱氨酸, 紫外-可见光谱

Abstract: Through ultraviolet-visible(UV-Vis) spectra, a strategy for the determination of cysteine(Cys) was established by simply assembling copper(Ⅱ) and 4-(2-pyridylazo)-resorcinol(PAR) in a molar ratio of 1: 1 in aqueous solution. Cys could be detected in 10 mmol/L 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid(HEPES) buffer(pH=7.0) system containing copper(Ⅱ)-PAR due to coordination competition. The Cu2+-PAR ensemble was highly selective for Cys without interference from other amino acids. From the UV-Vis absorbance value changes of Cu2+-PAR and Cu2+-PAR-Cys, the optimal coordinated ratio of PAR: Cu2+ was found to be 1: 1 and Cu2+:Cys was 1: 3. It is worthy mentioned that within the concentration range of 0—240 μmol/L in aqueous solution, the measurement of Cys conformed well with linear law, with an average coefficient of light extinction of 7519 L/(mol·cm) and a correlation coefficient of 0.9982. The whole recognition process for Cys gave rise to a rapid visual color change from pink to yellow which can be observed simulta-neously with naked eye.

Key words: Indicator displacement method, Copper(Ⅱ), 4-(2-Pyridylazo)-resorcinol, Cysteine, UV-Vis spectrum

中图分类号: 

TrendMD: