Enzyme Electrode for Amperometric Sensing of Acetylcholine and Acetylcholinesterase Inhibitors

摘要

One area of interest to our laboratory is in electrochemical biosensors for the detection of nerve agents (organophosphates, Sarin, VX) that act by inhibiting the enzyme acetylcholine. An amperometric biosensor was constructed based on a biomatrix composed of a three-enzyme reaction sequence to detect the conversion of acetylcholine to choline by acetylcholine. The enzyme matrix was electrically coupled to a glassy carbon electrode via a redox metallopolymer, which also regenerates the enzyme system. The electrode was held at a constant potential, and the conversion of substrate (acetylcholine) was measured amperometrically as a steady-state current. The presence of acetylcholinesterase-inhibiting agents can be detected by a drop in the response of the measured current.