Simultaneous Quantification of Three Major Triterpenoids in Radix asteris by High-performance Liquid Chromatography with Evaporative Light Scattering Detection

Introduction - Radix asteris, with triterpenoids as its main pharmacological effective compounds, has been widely used for moistening the lung, dispersing phlegm and relieving cough. Quantification of the triterpenoids is important for the quality control of Radix asteris. Objective - To establish a high-performance liquid chromatography method with evaporative light scattering detection for simultaneous determination of three major triterpenoids, shionone, friedelin and epi-friedelinol, in Radix asteris. Methodology - The optimal chromatographic conditions were achieved on an RP, column with gradient elution by acetonitrile and 0.05% acetic acid in 22 min with ELSD set at an evaporating temperature of 40 degrees C. Validation of the method included tests of linearity, sensitivity, precision, repeatability, stability and accuracy. Results - All calibration curves showed good linear regression (r(2)> 0.9991) within test ranges. The established method showed good precision and accuracy with overall intra-day and inter-day variations of 1.61-2.97 and 1.74-2.42%, respectively, and overall recoveries of 97.35-101.13% for the three compounds analysed. Conclusion - The method developed was successfully applied to quantify the main triterpenoids in 14 Radix asteris samples. Copyright C 2009 John Wiley & Sons, Ltd.