Development and validation of an LC method for determination of swertisin in rat plasma

A simple and sensitive reversed phase liquid chromatographic method with UV detection was developed and validated for determination of swertisin in rat plasma. Chromatographic separation was achieved on a Phenomenex Gemini C ₁₈ column (250 × 4.6 mm, 5 μm). The mobile phase consisted of acetonitrile and water (24:76) with 1% acetic acid and was delivered at a flow rate of 0.8 mL min^-1. The detection wavelength was set at 338 nm. Standard curves were linear (r ≧ 0.9976) in rat plasma over the concentration range of 0.102-10.2 μg mL^-1. Within- and between-day precisions ranged from 2.6% to 6.8% RSD. The lower limit of quantification was 0.102 μg mL^-1. The validated method has been successfully applied for the preliminary pharmacokinetic study of swertisin in rat.