Department of Chemistry, East China Normal University, Shanghai 200062, China.
Analyst. 2011 Dec 7;136(23):5084-90. doi: 10.1039/c1an15601b. Epub 2011 Oct 13.
An electrochemical platform for acetylcholinesterase (AChE) activity assay and its inhibitors screening is developed based on the Michael addition reaction of thiocholine, the hydrolysis product of acetylthiocholine (AsCh) in the presence of AChE, with the electrogenerated o-quinone of catechol-terminated SAMs on a gold electrode. For understanding and confirming the mechanism of the reaction, the electrochemical behaviors of Michael addition reaction of two model compounds, cysteine (CYS) and glutathione (GSH), towards the catechol-terminated SAMs have been studied. The enzyme kinetics and the inhibition effects of three types of AChE inhibitors, which are tacrine, carbofuran and parathion-methyl, have been investigated using an amperometric method. Among these three inhibitors, tacrine exhibits the strongest inhibiting effect, which is reinforced by the resulting data of kinetic studies on each inhibitor's influence upon the enzyme activity.
建立了一种基于乙酰胆碱酯酶（AChE）活性测定及其抑制剂筛选的电化学生物传感平台，该平台基于硫代胆碱（AChE 存在下乙酰硫代胆碱（AsCh）的水解产物）与金电极上的儿茶酚末端 SAM 电生成的邻醌之间的迈克尔加成反应。为了理解和确认反应机制，研究了两种模型化合物半胱氨酸（CYS）和谷胱甘肽（GSH）与儿茶酚末端 SAM 之间的迈克尔加成反应的电化学行为。使用安培法研究了三种 AChE 抑制剂（他克林、呋喃丹和甲基对硫磷）的酶动力学和抑制作用。这三种抑制剂中，他克林的抑制作用最强，动力学研究结果也证实了这一点，表明每种抑制剂对酶活性的影响。
