Determination of Urinary Caffeine Metabolites as Biomarkers for Drug Metabolic Enzyme Activities.

ABSTRACT: Caffeine is commonly taken via the daily dietary consumption of caffeine-containing foods. The absorbed caffeine is metabolized to yield various metabolites by drug-metabolizing enzymes, and measuring the levels of each caffeine metabolite can provide useful information for evaluating the phenotypes of those enzymes. In this study, the urinary concentrations of caffeine and its 13 metabolites were determined, and the phenotypes of drug metabolic enzymes were investigated based on the caffeine metabolite ratios. Human urine samples were pretreated using solid phase extraction, and caffeine and its metabolites were analyzed using liquid chromatography-tandem mass spectrometry. Based on the urinary caffeine metabolite concentrations, the caffeine metabolite ratios were calculated for six huma

SUBMITTER: Kim HJ 

PROVIDER: S-EPMC6723199 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature