title: Mechanized assay of serum cholinesterase by specific colorimetric detection of released acid.
abstract: An automated assay method has been developed for the measurement of serum cholinesterase activity. The samples were prepared by an automated liquid handling unit and incubated for 9.7 min at 30 degrees C, followed by automatic injection into a colorimetric flow injection determination system for acetic acid liberated from acetylcholine by cholinesterase catalytic activity. The coloration reaction employed is based upon the formation of 2-nitrophenylhydrazide utilizing a water-soluble carbodiimide and has a high selectivity for carboxylic acids. The coefficients of variation of the proposed method were 2.4% for within-run analysis (n = 14) and 2.6% for between-run analysis (n = 6). Sera of 55 hospitalized patients were analyzed and the values obtained correlated well with an automated differential pH method (gamma = 0.989).
authors.affiliation: Department of Pharmacy, College of Science and Technology, Nihon University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Y
authors.initials: Y
authors.lastname: Kabasawa
authors.forename: R
authors.initials: R
authors.lastname: Horikawa
authors.forename: T
authors.initials: T
authors.lastname: Tanimura
mesh_terms: D000085:Acetates / Q000032:analysis*; D019342:Acetic Acid; D000109:Acetylcholine / Q000378:metabolism; D002802:Cholinesterases / Q000097:blood*; D003124:Colorimetry / Q000379:methods; D005069:Evaluation Studies as Topic; D017022:Flow Injection Analysis / Q000379:methods; D006801:Humans; D006834:Hydrazines; D006863:Hydrogen-Ion Concentration; D010659:Phenylhydrazines; D015203:Reproducibility of Results
chemical_list: D000085:Acetates; D006834:Hydrazines; D010659:Phenylhydrazines; C060574:2-nitrophenylhydrazine; D002802:Cholinesterases; D000109:Acetylcholine; D019342:Acetic Acid