Determination of fucoxanthinol in rat plasma by liquid chromatography-tandem mass spectrometry

Previous studies have indicated that dietary fucoxanthin is mainly converted into fucoxanthinol (the deacetylated form) in mammals, but the pharmacokinetics of fucoxanthinol remains unknown. In this study, after intravenous (i.v.) and intragastric gavage (i.g.) administration of fucoxanthinol to rats at 0.8 and 20 mg/kg respectively, one-step protein precipitation with methanol was employed to prepared plasma samples, and an accurate and precise liquid chromatography-tandem mass spectroscopy (LC-MS/MS) method was developed to determine fucoxanthinol. Plasma samples were resolved by LC-MS/MS on a reverse-phase SB-C18 column equilibrated and eluted with acetonitrile (A, 0.1% formic acid) and water (B, 0.1% formic acid) (A:B = 92:8, v/v) at a flow rate of 0.5 mL/min and the injection volume was 5 μL. Analytes were monitored by Selected-reaction monitoring in positive electrospray ionization mode. The calibration curves for fucoxanthinol were linear over the range 1.17-300 ng/mL. The inter-day and intra-day accuracy and precision were within 1.55%-7.90%. The method was applied successfully in a pharmacokinetic study of fucoxanthinol and the resulting bioavailability was calculated.