Immobilized enzyme flow-injection conductimetric system for the determination of acetylcholine

Abstract

A flow injection system for the determination of acetylcholine, based on the use of immobilized cholinesterase in glass beads, a diffusion membrane and a conductimetric cell is described. In this approach acetic acid formed by the action of acetylcholinesterase on acetyl choline permeates through a PTFE membrane and is received by a stream of deionized water, which carries the solution to the conductivity cell. Linearity for acetylcholine concentration and conductimetric response with a useful range of 10^–5–10^–3 mol l^–1 was observed.