Development and validation of a high-performance liquid chromatographic method for determination of pinocembrin in rat plasma: application to pharmacokinetic study.

A sensitive and specific reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-UV-HPLC) method has been developed and validated for the identification and quantification of pinocembrin in rat plasma using chrysin as the internal standard. Following protein precipitation with acetonitrile, the analytes were separated by the mobile phase 0.01 M ammonium acetate (pH 4.0)-methanol (35:65, v/v) with an Agilent TC-C18 column (5 microm, 4.6 mm x 150 mm) at a flow rate of 1 ml/min, column temperature 40 degrees C and detection wavelength 290 nm. A good linear relationship was obtained in the concentration range studied (0.07-133.33 microg/ml, r=0.9995). The lowest limit of quantification (LLOQ) was 66.7 ng/ml and the lowest limit of detection (LLOD) was 25 ng/ml. Average recoveries ranged from 93.9 to 97.8% in plasma at the concentrations of 0.33 and 33.33 microg/ml. Intra- and inter-batch relative standard deviations were 0.15-2.03 and 1.18-9.96%, respectively. This method was successfully applied to the pharmacokinetic studies in rats after intravenous administration of pinocembrin.