物理化学学报 >> 2009, Vol. 25 >> Issue (03): 457-462.doi: 10.3866/PKU.WHXB20090311

研究论文 上一篇    下一篇

细胞色素c在硒代胱氨酸修饰电极上的直接电化学

梁敏思 白燕 刘敏 郑文杰   

  1. 暨南大学化学系, 广州 510632
  • 收稿日期:2008-11-13 修回日期:2008-12-17 发布日期:2009-03-02
  • 通讯作者: 白燕; 郑文杰 E-mail:tbaiyan@jnu.edu.cn;tzhwj@jnu.edu.cn

Electrochemical Reaction of Cytochrome c at Selenocystine Self-assembled Monolayers Modified Electrodes

 LIANG Min-Si, BAI Yan, LIU Min, ZHENG Wen-Jie   

  1. Department of Chemistry, Jinan University, Guangzhou 510632, P. R. China
  • Received:2008-11-13 Revised:2008-12-17 Published:2009-03-02
  • Contact: BAI Yan; ZHENG Wen-Jie E-mail:tbaiyan@jnu.edu.cn;tzhwj@jnu.edu.cn

摘要:

采用电化学和接触角实验方法研究了硒代胱氨酸自组装膜修饰金电极(SeCys SAMs/Au)和十六烷基三甲基溴化铵(CTAB)-硒代胱氨酸自组装复合膜修饰金电极(CTAB-SeCys SAMs/Au)的特性. 探讨了细胞色素c(Cyt c)在SeCys SAMs/Au电极和CTAB-SeCys SAMs/Au电极上的电化学行为. 实验证明SeCys可促进Cyt c在电极上的氧化还原反应, 加入CTAB后其与SeCys之间的协同作用可在Cyt c与电极之间形成一个开放的通道, 促进作用更加明显, 且在一定浓度范围内, 随CTAB浓度(1×10-5-1×10-4 mol·L-1)的增大, Cyt c在CTAB-SeCys SAMs/Au电极上的氧化还原电流增大, 在接近临界胶束浓度处出现极大值. 在CTAB-SeCys SAMs/Au电极上Cyt c产生一对氧化还原峰, 其峰电位分别为0.305和0.235 V, 其电化学过程受扩散控制. 光谱实验证实SeCys对Cyt c电化学过程的促进作用是由于SeCys与Cyt c中赖氨酸残基的结合.

关键词: 硒代胱氨酸, 细胞色素c, 自组装, 表面活性剂

Abstract:

Properties of selenocystine self-assembled monolayers at gold electrode (SeCys SAMs/Au) and hexadecyltrimethylammonium bromide (CTAB)-selenocystine self-assembled bilayers at a gold electrode (CTAB-SeCys SAMs/Au) were investigated by electrochemical and contact angle experiments. The electrochemical behavior of cytochrome c (Cyt c) on SeCys SAMs/Au and CTAB-SeCys SAMs/Au electrodes are discussed. We show that SeCys and CTAB-SeCys can promote the redox reaction of Cyt c on these electrodes. The promoting effect of CTAB-SeCys is stronger than of SeCys. We found that the current of the redox reaction of Cyt c increased when the concentration of CTAB increased from 1×10-5 to 1×10-4 mol·L-1. The maximumcurrent was observed when the concentration was close to the critical micelle concentration (cmc) of CTAB. The redox peaks of Cyt c on the CTAB-SeCys SAMs/Au electrode are 0.305 and 0.235 V, respectively and the electrochemical behavior is diffusion controlled. The promoting effect of SeCys was found to be due to a combination of SeCys and remnant group of lysine in Cyt c.

Key words: Selenocystine, Cytochrome c, Self-assemble, Surfactant

MSC2000: 

  • O646