Characterization of glucuronide metabolites of carbamazepine in human urine by gas chromatography and mass spectrometry

Abstract

Glucuronide metabolites of carbamazepine (5 H-dibenz[b,f]azepine-5-carboxamide) were identified in human urine following chromatography on XAD-2 resin, permethylation, and combined gas chromatography and mass spectrometry with an SE-30 capillary column. Eight glucuronide metabolites, previously unidentified in man, were characterized as their permethylated derivatives. These included carbamazepine N-glucuronide (M+. 482), three isomers of dihydroxycarbamazepine O-glucuronide (M+. 542), three isomers of hydroxymethoxycarbamazepine O-glucuronide (M+. 542), and one isomer of hydroxycarbamazepine O-glucuronide (M+. 512). Other glucuronide metabolites, previously identified following enzymatic hydrolysis, were characterized as the unhydrolyzed, permethylated glucuronides, 10,11-dihydro-10,11-di--hydroxy carbamazepine O-glucuronide (M+. 544), and three isomers of monohydroxycarbamazepine O-glucuronide (M+. 512).