Isolation, structure characterization and quantification of related impurities in asperosaponin VI

AimTo study the related impurities in asperosaponin VI bulk drug and to develop a high performance liquid chromatography (HPLC) method for the determination of asperosaponin VI and its related impurities.MethodsThe related impurities were detected in asperosaponin VI bulk drug by a newly developed HPLC method, obtained by ODS column chromatography and semi-preparative HPLC methods, and the structures were elucidated by TOF-MS, IR, and NMR techniques. The HPLC method was validated according to ICH guidelines for asperosaponin VI and its related impurities.ResultsSeven related impurities (Imp 1-7) were isolated from asperosaponin VI bulk drug. Impurity 3 was found to be a mixture of two epimers, and was first reported in the paper. The validation results showed good sensitivity, specificity, linearity (r2 ≥ 0.997 9), precision (RSD < 5.0%), accuracy (recoveries in the range of 94.61%–106.51%) and robustness.ConclusionThe developed HPLC method is suitable for the quality control of asperosaponin VI bulk drug.