Retracted: Determination of scutellarin isomer, a predominant metabolite of scutellarin, in human plasma by HPLC/tandem mass spectrometry and its application to a pharmacokinetic study in Chinese healthy volunteers

Abstract

A liquid chromatography/tandem mass spectrometric (LC-MS/MS) method was developed to determine scutellarin isomer, a predominant metabolite of scutellarin, in human plasma for the pharmacokinetic study of scutellarin in Chinese healthy volunteers. Samples were acidified with formic acid and extracted with ethyl acetate. Chromatographic separation was achieved on a C 18 column with the mobile phase of water (containing 0.5% formic acid) and methanol (33:67, v/v). The analytes were detected using an electrospray positive ionization mass spectrometry in the selected reaction monitoring (SRM) mode. The calibration curve was linear over the range of 0.5-200.0 ng/mL and the lower limit of quantification was 0.5 ng/mL. The average extraction recoveries were 81.1 ± 7.5, 84.5 ± 6.9 and 83.4 ± 5.8% at concentrations of 2.0, 20.0 and 100.0 ng/mL, respectively. The intra-and inter-day precisions at three different concentrations were all less than 7.3% and accuracies were within the range 98.9-106.7%. The method described was precise, accurate and successfully applied to evaluate the pharmacokinetics and bioequivalence of scutellarin in 20 Chinese healthy volunteers. The results showed that the main pharmacokinetic parameters between scutellarin guttate pills and tablets had no statistically significant difference and the two formulations were bioequivalent.