An HPLC assay procedure of sensitivity and stability for measurement of acetylcholine and choline in neuronal tissue.

A method is presented for the sensitive and specific determination of acetylcholine and choline in neuronal tissue. The method is based on the separation of acetylcholine and choline by reversed-phase HPLC, passing the eluent into a post-column reactor containing choline oxidase and acetylcholinesterase covalently bound to vinyl sulphone bonded onto a hydroxyethyl methacrylate support, and electrochemical detection of the hydrogen peroxide formed. The limit of detection of the procedure is 1 pmol for acetylcholine and 500 fmol for choline. The excellent baseline stability of the method ensures the rapid and reliable processing of a large number of samples.