金电极上L-半胱氨酸短链分子自组装单层的电化学性能和拉曼光谱研究

用循环伏安法分别测定了金电极表面L-半胱氨酸(L-Cys)和十二硫醇自组装单分子层的电化学行为, 实验发现虽然单层结构排列致密, 但并不能有效地阻碍铁氰化钾与电极间异相电子转移过程, 同时观察到十二烷基硫醇自组装层能较好地阻碍电子转移作用. 运用表面增强拉曼散射光谱技术, 以十二烷基硫醇作为缺陷探针, 从分子水平上证实了L-半胱氨酸自组装单层的稳定性和致密性.

Electrochemical and Raman Scattering Studies of Short-chain L-Cysteine Self-assembled Monolayers on the Gold Electrode

The gold electrodes were self-assembled with L-cysteine and dodecanethiol,respectively.Using potassium ferricyanide as an electron transfer probe,the electrochemical behavior of the resulting monolay-ers on the gold electrode surface was investigated.Experimental results showed that the electrode with L-cysteine self-assembled monolayers should be very stable and dense,which failed to block the electron transfer(ET)between the gold electrode and potassium ferricyanide while the dodecanethiol modified gold electrode could inhibit that ET process effectively.Surface enhanced Raman scattering spectroscopic obser-vations confirmed the stability and compact feature of L-cysteine monolayers using dodecanethiol as a probe for detecting the defects.