title: Isolation, structure characterization and quantification of related impurities in asperosaponin VI.
abstract: OBJECTIVE
  To 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.
  
  
  METHODS
  The 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.
  
  
  RESULTS
  Seven 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 (r(2) ≥ 0.997 9), precision (RSD < 5.0%), accuracy (recoveries in the range of 94.61%-106.51%) and robustness.
  
  
  CONCLUSIONS
  The developed HPLC method is suitable for the quality control of asperosaponin VI bulk drug.
authors.affiliation: State Key Laboratory of Natural Products and Functions, China Pharmaceutical University, Nanjing 210009, China.
authors.forename: De
authors.initials: D
authors.lastname: Ji
authors.forename: Yun-Fei
authors.initials: YF
authors.lastname: Liu
authors.forename: Qiao-Han
authors.initials: QH
authors.lastname: Wang
authors.forename: Chun-Feng
authors.initials: CF
authors.lastname: Zhang
authors.forename: Zhong-Lin
authors.initials: ZL
authors.lastname: Yang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004340:Drug Contamination / Q000517:prevention & control*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D012503:Saponins / Q000737:chemistry*
chemical_list: D012503:Saponins; C534004:akebia saponin D
keywords: HPLC-UV; Method validation; Related impurities; Structure characterization; asperosaponin VI