La^（3＋）和Ca^（2＋）对金电极上谷胱甘肽单分子膜离子闸门的影响

Effect of La 3+ and Ca 2+ on “Ion Gate” of the Glutathione Monolayer Gold Electrode

谷胱甘肽能自组装吸附到金电极上形成单分子膜。该膜能阻止Ｆｅ（ＣＮ）３－６离子在金电极上还原，起离子闸门的作用。当溶液中加入Ｌａ３＋或Ｃａ２＋时，Ｆｅ（ＣＮ）３－６离子穿透膜的能力得到改善。本课题应用循环伏安法和计时库仑法，在ｐＨ５６的溶液中研究了Ｌａ３＋的调控能力。与Ｃａ２＋比较，发现在改变谷胱甘肽单分子膜的结构和Ｆｅ（ＣＮ）３－６离子的扩散系数方面。

lutathione(GSH) can be self assembled a monolayer on Au electrode which acts as an “ion gate” inhibiting electron transferation from electrode to Fe(CN) 3- 6 ions. The addition of La 3+ or Ca 2+ ions can regulate the ion gate which responses the Fe(CN) 3- 6 reduction on electrode. The regulative function of La 3+ on the ion gate response was studied in aqueous Fe(CN) 3- 6 solution at pH 5 6 and compared with that of Ca 2+ . The methods of cyclic voltammetry and chronocoulommetry were applied to examine the effect of La 3+ or Ca 2+ ions on the conformation of GSH monolayer and the diffusion coefficient of Fe(CN) 3- 6 ions. It was found that La 3+ has much stronger effect than Ca 2+ .