Determination of paraoxon by combined bovine liver esterase inhibition and gas-liquid chromatography.

A combined gas-liquid chromatography and enzyme procedure is described for the determination of organophosphorus compounds that show anticarboxylesterase activity in vitro. The method is based on the enzyme hydrolysis of 1-naphthyl acetate and on the determination of both the release 1-naphthol and the unhydrolyzed 1-naphthyl acetate by gas-liquid chromatography. With bovine liver as the source of enzyme the detection limit for paraoxon was 13 ppb.