Qualitative and Quantitative Analysis of Constituents in Si-jun-zi Tang Decoction by HPLC-DAD-ELSD and HPLC-ESI-MS

Aim: The purpose of this study is to explore a convenient, accurate and reliable method for quality control of Si-jun-zi Tang (SJZT) decoction. Methods: A high-performance liquid chromatography coupled with diode array and evaporative light scattering detectors (HPLC-DAD-ELSD) method and a HPLC coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS) method were developed for the qualitative and quantitative analysis of multiple constituents in SJZT. The chromatographic separation of multiple constituents was performed on a Boston pHlex ODS column and a C18 guard column with a gradient elution program consisting of 0.1% aqueous formic acid and acetonitrile at a flow rate of 0.7 mL/min. Results: A total of 23 constituents (7 ginsenosides, 9 licorice flavonoids, 5 licorice saponins and 2 atractylenolides) were verified based on peak retention time, ultraviolet-visible (UV) spectrum and MS data of HPLC-DAD-ELSD and HPLCESI- MS methods. The HPLC-DAD-ELSD method was successfully applied to quantify 11 major constituents (liquiritin apioside, liquiritin, Re/Rg1, isoliquiritin apioside, isoliquiritin, ononin, Rb1, Rg2, glycyrrhizic acid, and atractylenolide III) in SJZT with good linearity (R&2 > 0.9990), acceptable precision (RSD < 3.0%) and high recovery (93.4%-101.7%). Conclusion: The combined methods of HPLC-DAD-ELSD and HPLC-ESI-MS proved to be convenient, accurate and reliable methods for qualitative and quantitative analysis of SJZT.