Amperometric acetylcholine and choline sensors with immobilized enzymes

Acetylcholine and choline sensors are prepared by immbilizing enzymes on nylon net attached to a hydrogen peroxide snsor. Choline oxidase is used for the choline sensor; acetylcholinesterase choline oxidase are used for acetylcholine. The platinum/silver electrode pair is polarized at +0.6 V. The assembly is protected with an acetate cellulose membrane to enhance selectivity. The ranges measured are 1–10 μmol l^?1 in 0.1–1 ml of sample. The response times are 1–2 min.