Liquid chromatographic method for determination of piperine in rat plasma: application to pharmacokinetics

Piperine, a major alkaloid of Piper longum and Piper nigrum has been reported to have several pharmacological/toxicological effects. Though a number of methods for analysis of this omnipresent food component in pepper fruits are available, its analysis in body fluids has been largely neglected. A high-performance liquid chromatography method for the analysis of piperine in rat plasma is presented in this communication. Analysis was performed using a Symmetry® C18 column (250×4.6 mm) by isocratic elution with 25 mM KH2PO4 (pH 4.5)–acetonitrile (35:65) and UV detection at 340 nm. The calibration plot was linear over the range studied (2–2000 ng) with correlation coefficient of 0.9984. Limit of detection and limit of quantitation were 1 ng/ml and 3 ng/ml, respectively. Good overall recovery (85.5±6%) was obtained with 4 ml ethyl acetate and extraction time of 3 min. Intra- and inter-assay coefficient of variation was found to be less than 7.5%. Plasma concentration–time profile of piperine in a conscious rat implanted with jugular vein cannula was obtained using this method. The method is simple, sensitive and reproducible.