Rapid and Sensitive RP-LC Method for the Quantification and Pharmacokinetic Study of p-Hydroxyphenethyl Anisate in Rat Plasma

Abstract

A rapid, sensitive and specific reversed-phase liquid chromatographic method was developed and validated for the quantification of p-hydroxyphenethyl anisate (HPA), which is one of the main constituents of Notopterygium Radix (underground parts of Notopterygium incisum and N. forbesii), in rat plasma, and study its pharmacokinetics after the intravenous administration of 40 mg kg−1 HPA to rats. The method involves a plasma clear-up step using liquid–liquid extraction by ethyl acetate, followed by RP-LC separation and detection. Separation of HPA was performed on an analytical Diamonsil ODS C18 column equipped with a Dikma ODS C18 EasyGuard column using a mobile phase consisting of MeOH–H2O (75:25, v/v) at a flow-rate of 1.0 mL min−1. The UV detection was performed at a wavelength of 256 nm. The linear calibration curves were obtained in the concentration range of 0.05–5.0 μg mL−1 (r = 0.9992, n = 5) in rat plasma with the lower limit of detection of 0.01 μg mL−1 and the lower limit of quantification of 0.04 μg mL−1, and the extraction recovery of HPA was calculated to be the range of 82.01–86.66%. The intra- and inter-day precisions in terms of % relative standard deviation were lower than 2.33 and 3.99% in rat plasma, respectively, with accuracies ranging from 91.22 to 110.5%. The developed method was suitable for the determination and pharmacokinetic study of HPA in rat plasma.