Determination of Chinoform and Its Metabolites in Plasma by Gas Chromatography-Mass Spectrometry

Abstract

A gas chromatographic-mass spectrometric (GC-MS) procedure using selected ion monitoring is described for the determination of chinoform (CF) and its two metabolites, glucuronide and sulfate, in plasma. The method consists of extraction of CF from plasma with pyridine-benzene (1 : 9, v/v) mixture containing 5-chloro-7-bromo-8-quinolinol as an internal standard, selective hydrolysis and extractions of the two conjugates, acetyl derivatizations and GC-MS analysis. The lower limit of CF quantitation by the present method was 3.3 pmol (1 ng) in 0.1 ml plasma volume. The method has sufficient sensitivity to permit pharmacokinetic studies with rats after single oral administration of CF.