Anal Chem. 2009 Aug 15;81(16):7123-6. doi: 10.1021/ac901126d.
Voltage-controlled amplification of the output current of an enzymatic detector has been demonstrated. By application of an external voltage between the gating electrode and the working electrode on which the enzyme glucose oxidase was immobilized, the biocatalytic output current of the detector was increased significantly, allowing the detection limit of glucose to be lowered from the millimolar level to the picomolar level. The current amplification could be reversibly controlled by the applied voltage. Application of this technique to the ethanol-alcohol dehydrogenase system showed similar results. The detection setup suggests that the output current is controlled by the electric field at the interface between the solution and the working electrode. The enzyme's biospecificity was preserved in the presence of the field. The detector, with its output current controlled by a voltage applied at a third electrode, behaves as a field-effect transistor, whose current-generating mechanism is the conversion of an analyte to a product using an enzyme as catalyst. In a broader sense, the operation of the detector shows a means for manipulating a redox enzymatic reaction.
已经证明了酶检测器的输出电流可以通过电压控制进行放大。通过在门控电极和固定有葡萄糖氧化酶的工作电极之间施加外部电压，可以显著增加生物催化检测器的输出电流，从而将葡萄糖的检测限从毫摩尔降低到皮摩尔水平。电流放大可以通过施加的电压进行可逆控制。将该技术应用于乙醇-醇脱氢酶体系也得到了类似的结果。检测装置表明，输出电流受溶液和工作电极之间界面处电场的控制。在电场存在的情况下，酶的生物特异性得以保留。该检测器的输出电流由施加在第三电极上的电压控制，其行为类似于场效应晶体管，其电流产生机制是使用酶作为催化剂将分析物转化为产物。从更广泛的意义上讲，该检测器的工作方式展示了一种用于操纵氧化还原酶反应的手段。
