亚硒酸钠在L-半胱氨酸自组装类生物膜修饰电极上的电化学行为  

Electrochemical Properties of Sodium Selenite on a Bionic Membrane of Gold Electrode Modified by L-Cysteine Self-assembled Monolayer

作　　者：温金凤[1] 朱爱花[1] 崔胜云[1] 

机构地区：[1]长白山生物资源与功能分子教育部重点实验室延边大学,延吉133002

出　　处：《分析化学》2009年第12期1771-1775,共5页Chinese Journal of Analytical Chemistry

摘　　要：利用L-半胱氨酸自组装膜修饰金电极(L-Cys,Au/SAMs),在0.05mol/L H2SO4底液中研究了Na2SeO3的电化学特性。在0.00～1.30 V(vs.SCE)电位范围内对微量Na2SeO3进行循环伏安扫描,发现L-Cys,Au/SAMs修饰电极在峰电位0.89 V处有灵敏的Se的氧化溶出峰。通过比较裸金电极和修饰电极在Na2SeO3溶液中的电化学特性发现,修饰电极通过巯基中的S与Na2SeO3发生氧化还原作用生成Se,且修饰电极对沉积在电极表面的Se的氧化过程具有催化作用。根据Na2SeO3在单分子膜上的电化学行为,提出了单分子膜中硫(Au-S)与Se(作用生成Se的反应机理、Se电化学催化氧化机理及巯基化合物通过生成纳米硒生物吸收Se的类生物膜模型。The cyclic vohammetric behaviors of sodium selenite on the gold electrode modified by L-cysteine self-assembled monolayer （L-Syc,Au/SAMs） has been investigated in 0.05 mol/L H2SO4 solutions with sodium selenite. Sensitive anodic stripping current of selenium （Se） with the peak potential at 0.99 V （vs. SCE） has been observed. In comparison with the electrochemical properties of sodium selenite on the modified electrode with those on the naked gold electrode, it was found that selenite was reduced to selenium by the redox interaction with sulfur on the monolayer and the monolayer catalytically oxidizes Se as the electrode was posi- tively scanned. According to the electrochemical properties of sodium selenite both on the naked and modified gold electrode, the Se deposition mechanism and catalytic mechanism as well as bionic membrane model were proposed for the bio-utilization of selenite through nano scale selenium.

关 键 词：L-半胱氨酸 亚硒酸钠 修饰电极 纳米硒 伏安法 

分 类 号：O657.1[理学—分析化学]