Simultaneous determination of 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol in rat plasma by liquid chromatography-mass spectrometry: Application to pharmacokinetics

A rapid high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed and validated for simultaneous quantification of 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol in rat plasma after oral administration of ginger oleoresin. Plasma samples extracted with a liquid-liquid extraction procedure were separated on an Agilent Zorbax StableBond-C-18 column (4.6 mm x 50 mm, 1.8 mu m) and detected by MS with electrospray ionization interface in positive selective ion monitoring (SIM) mode. Calibration curves (1/x(2) weighted) offered satisfactory linearity (r(2) > 0.995) in a wide linear range(0.0104-13.0 mu g/mL for 6-gingerol, 0.00357-4.46 mu g/mL for 8-gingerol, 0.00920-11.5 mu g/mL for 10-gingerol and 0.00738-9.22 mu g/mL for 6-shogaol). The lower limit of quantification (LLOQ) was in a range of 3.57-10.4 ng/mL. The analytes and internal standard can be baseline separated within 6 min. Inter- and intra-day assay variation was less than 15%. This developed method was Successfully applied to pharmacokinetic studies of ginger oleoresin after oral administration to rats. Glucuronide of 6-gingerol was determined after beta-glucuronidase hydrolysis for more information. and the intestinal glucuronidation was further confirmed by comparison of plasma samples of hepatic portal vein and femoral vein. (C) 2009 Elsevier B.V. All rights reserved.