Continuous monitoring of arylesterase in human serum

Arylesterase (EC 3.1.1.2) activity in serum was specifically measured using thiophenyl acetate in a mechanized assay at 37 degreesC with 4-bromophenyl boronic acid as inhibitor of cholinesterase and hexacyanoferrate-III as ind icator. The systematic development of a routine method, apparent limitation s of thiophenyl compounds as arylesterase substrates, some kinetic constant s of the enzyme, analytical variables such as precision (within-run < 2% an d between-run < 2.5% relative standard deviation) and a preliminary referen ce interval (19.5-52.4 kU/l) for adults are described. (C) 2001 Elsevier Sc ience B.V. All rights reserved.