title: [HPLC determination of insulin and its related substances in insulin powder for inhalation].
abstract: OBJECTIVE
  To determine insulin and its related substances in insulin powder for inhalation by reversed phase high performance liquid chromatography method.
  
  
  METHODS
  The initial mobile phase was solution A (0.1% trifluoroacetic acid-acetonitril 70:30) and changed to solution B (0.1% trifluoroacetic acid-acetonitril 60:40) in 30 minutes. The flow rate was 2.0 mL.min-1, the column temperature was 30 degrees C, the wave length was 280 nm, the injected volume was 20 microL.
  
  
  RESULTS
  Insulin was well separated from other peaks induced in different conditions. There was good linear relationship between the amount of insulin and its peak area, the RSD was 1.1%, the insulin solution for determination was stable in 12 hours, and the quantity detected was near the added.
  
  
  CONCLUSIONS
  The method is simple and accurate to detect insulin and its related substances in insulin and its preparations.
authors.affiliation: Department of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China.
authors.forename: Xi-jing
authors.initials: XJ
authors.lastname: Chen
authors.forename: Jia-bi
authors.initials: JB
authors.lastname: Zhu
authors.forename: Guang-ji
authors.initials: GJ
authors.lastname: Wang
authors.forename: Ming-xia
authors.initials: MX
authors.lastname: Zhou
authors.forename: Yue-ning
authors.initials: YN
authors.lastname: Xu
mesh_terms: D000280:Administration, Inhalation; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D007328:Insulin / Q000008:administration & dosage / Q000032:analysis*; D011208:Powders / Q000032:analysis
chemical_list: D007328:Insulin; D011208:Powders