Assay of Four Saponins in Astragali Radix by HPLC-ELSD / 医药导报

ABSTRACT

Objective To study the feasibility of high performance liquid chromatography-evaporative light scattering detector ( HPLC-ELSD) in quantitative analysis of multi-components ( QAMS) by single marker. Methods Four saponins in Astragali Radix were simultaneously determined by HPLC-ELSD using external standard method, and malonylastragaloside I served as internal standard. The relative correction factors between internal standard and astragaloside Ⅰ, astragaloside Ⅱ and astragaloside Ⅳ were calculated, and the stability was investigated. Results Astragaloside Ⅳ in Astragali Radix was little, while malonylastragalosideⅠand AstragalosideⅠwere abundant.The relative correction factors lacked stability, so ELSD could not be used in QAMS. Conclusion HPLC-ELSD can precisely determine contents of four saponins in Astragali Radix. The detector needs to be further studied when the components have poor ultraviolet absorption such as saponins by QAMS.