Development of rapid and simultaneous quantitative method for green tea catechins on the bioanalytical study using UPLC/ESI-MS.

A rapid and quantitative analytical method for the simultaneous determination of green tea catechins using ultra-performance liquid chromatography/electrospray ionization-mass spectrometry was developed. Total analytical run time was 3.5 min for the detection of (-)-epicatechin (EC), (-)-epicatechin-3-O-gallate (ECG), (-)-epigallocatechin (EGC), (-)-epigallocatechin-3-O-gallate (EGCG) and myricetin as the internal standard (IS) in rat plasma. The calibration curves were linear over the range of 10-5000 ng/mL for all the catechins. The inter- and intra-day precision (relative standard deviation) and accuracy (percentage deviation) of the method were both lower than 10%. The average extraction recoveries in plasma ranged from 68.5 to 86.5%, and the lower limits of quantification of EC, EGC, ECG and EGCG were 10 ng/mL with a signal-to-noise ratio of >10. The assay developed was successfully applied to a pharmacokinetic study of catechins following intravenous and intragastric administrations of green tea extract in rats. Plasma concentrations of four catechins were detected up to 5-24 h after administration, and the pharmacokinetic parameters of catechins were in agreement with previous studies. From these findings, taken together with the high productivity and precision, the developed method could be a reliable and reproducible tool for the evaluation of pharmacokinetic properties of catechins.