High-performance liquid chromatographic assay to detect hydroxylate and conjugate metabolites of propofol in human urine

This paper describes a HPLC method for the simultaneous detection of phase I (2,6-diisopropyl-1–4-quinol and 2,6-diisopropyl-1–4-quinone) and phase II (4-(2,6-diisopropyl-1–4-quinol)-sulphate, 1-(2,6-diisopropyl-1–4-quinol)-glucuronide, 4-(2,6-diisopropyl-1–4-quinol)-glucuronide, and propofol-glucuronide) metabolites of propofol in human urine samples. Separation was based on a simple mobile phase and a reversed-phase chromatographic column. Metabolite identification was performed by UV spectrum on a diode-array detector and by LC–APCI–MS. The identification was also carried out using in vitro incubation mixtures (cytosol and microsomes prepared from liver) from several species: human, rat and rabbit. This assay was performed using UV, fluorescence and electrochemical detection modes. Each of these was analyzed and discussed.