L-半胱氨酸和胱胺共自组装膜活体检测抗坏血酸（英文）

Cysteine and Cystamine Co-Self-Assembled Monolayers for in Vivo Detection of Ascorbic Acid

自组装单分子膜(SAM)由于其独特的物理化学性质近年来受到了极大的关注. SAM通过金硫键在电极表面形成高度有序的单分子膜,该稳定的分子膜不仅可以调节表面的亲疏水性质,而且可以促进电极表面氧化还原活性分子的反应速率.本论文提出了一种简单有效的方法,在金微电极上构建半胱氨酸和胱胺共自组装单分子膜用于活体内抗坏血酸的检测.研究发现,当混合单分子层中半胱氨酸和胱胺的摩尔比为1:1时,可以在低电位下(约为0.10 V)显著增强抗坏血酸氧化的电子转移动力学,同时该膜能在一定程度上抵抗蛋白质在电极表面的非特异性吸附.将共自组装单分子膜应用到活体检测中,作者检测到鼠纹状体中抗坏血酸的基准值为257±30μmol·L-1(n=3).本论文为活体电化学检测提供了一种简单、有效的方法.

Self-assembled monolayers(SAMs),which form highly ordered monolayers on the electrode surface through the gold-suffer bond,have attracted much attention in recent years.This stable layer not only can regulate the wettable properties of surface,but also can act as a promoter towards redox-active molecules.Here,we developed a simple and effective method to construct cysteine and cystamine co-self-assembled monolayer on gold microelectrode for in vivo detection of ascorbic acid(AA).The molar ratio at 1:1 of mixed monolayer has been found the optimum to enhance the electron-transfer kinetics of AA oxidation at low potential(ca.0.10 V),meanwhile,it could resist the non-specific adsorption of protein at electrode surface.The application of the co-self-assembled monolayer is preliminarily demonstrated for in vivo detection and the basal level of striatum AA was determined to be 257±30μmol·L-1(n=3).This study offers a general and effective approach for in vivo electrochemistry with high reliability and simplified procedures.