Determination of palmatine in rabbit plasma by RP-HPLC with solid-phase extraction

A rapid and specific reversed-phase high performance liquid chromatography (RP-HPLC) method for the determination of palmatine in rabbit plasma has been developed and validated. The chromatographic separation was performed on a C-18 column at 40 degrees C. The mobile phase, delivered at 1.0 mL min(-1), consisted of acetonitrile/phosphate buffer (pH 3.0) 40:60 (v/v). The detection wavelength was set at 345 nm. Palmatine and internal standard (15) berberine were extracted from plasma by solid-phase extraction using Cl 8 cartridges. Linearity was confirmed in the concentration range of 0.01 to 5 mu g mL(-1), the inter-day and intra-day RSDs were within 10.0, the recoveries of palmatine ranged from 93.1 to 110.3, and the limit of detection (LOD, S/N > 3) was 0.002 mu g mL(-1). The method is applicable to the determination of palmatine in rabbit plasma after intravenous administration of palmatine.