Study on Determination of Triterpenoids in Chaenomeles by High Performance Liquid Chromatography and Sample Preparation with Matrix Solid Phase Dispersion

A new method for the simultaneous determination of the major triterpenoids in Chaenomeles (Chinese medicinal herb) by high performance liquid chromatography (HPLC) and sample preparation with matrix solid phase dispersion (MSPD) was developed. A 0.1 g of sample was placed into an agate mortar and gently blended with 0.4 g silica gel to obtain a homogeneous mixture. This mixture was introduced into a Teflon cartridge, and the triterpenoids fraction was eluted from the cartridge with dichloromethane‐acetone (85:15). The residue was dissolved with methanol after the evaporation of the solvent (dichloromethane and acetone). The triterpenoids were separated on a ZORBAX Stable Bound (4.6 mm × 100 mm, 1.8 μm) C₁₈ column by gradient elution with acetonitrile and water as the mobile phase and detected with evaporative light scattering detection. This method provides good reproducibility and sensitivity for the quantification of seven major triterpenoids, namely erythodiol, betulin, acetyl ursolic acid, ursolic acid, oleanolic acid, betulinic acid, pomolic acid, respectively. The relative standard derivations of overall intra‐day variations were less than 2.0%, and the relative standard derivations of inter‐day variations were less than 2.5%. The standard recoveries (three different concentrations of markers: 0.1, 0.5 and 2.0 mg) ranged from 97‐103%. The results demonstrate that this method is simple, sensitive, selective, and suitable for the quality control of this commonly used Chinese medicinal herb.