Abstract: A high performance liquid chromatographic method was developed for the determination of ligustrazine in human plasma. The chromatographic separation was performed on a Luna C18 column (150 mm×4.6 mm i.d., 5 μm) at column temperature of 40 ℃. The mobile phase, a mixture of methanol-acetonitrile-acetate buffer of pH 5.0 (50∶8∶42, v/v), was delivered at a flow rate of 1.0 mL/min. The detection wavelength was 280 nm. Plasma samples were prepared with a C8 solid-phase extraction column. Linearity was confirmed in the mass concentration range of 25-5000 μg/L with the correlation coefficient of 0.9999. The extraction recovery of ligustrazine ranged from 96.72％ to 100.90％. The relative standard deviations (RSDs) of intra- and inter-day assay at the mass concentrations of 50, 500 and 3000 μg/L were less than 8.64% and the accuracies were between 99.59%-103.26%. The limit of detection (LOD) was 10 μg/L. The results of this method validation satisfactorily meet the acceptance criteria of bioanalysis and the method is applicable to the pharmacokinetic studies of ligustrazine in human beings.

Key words: human plasma , ligustrazine, high performance liquid chromatography