title: The importance of sample preservation temperature for analysis of the redox state of human serum albumin.
abstract: BACKGROUND
  Human serum albumin (HSA) is a mixture of human mercaptalbumin (HMA, reduced form) and nonmercaptalbumin (HNA, oxidized form).
  
  
  METHODS
  We have developed a convenient high-performance liquid chromatographic (HPLC) system for the separation of HSA into HMA and HNA, and studied the mercapt<==>nonmercapt conversion (i.e., dynamic change in the redox state) of HSA. Examination of long-term sample preservation temperature on the redox state of HSA is of fundamental importance for analysis of defense systems against oxidants in humans.
  
  
  RESULTS
  The HMA fraction of HSA (f(HMA)) was markedly decreased, i.e., the redox state of HSA samples was more oxidized, when they were kept even at -20 degrees C for 170 days. Moreover, the redox states of five commercial HSA products were analyzed and the results were compared with those for normal control subjects.
  
  
  CONCLUSIONS
  Surprisingly, marked decreases in f(HMA) value for all commercial HSA products were observed.
authors.affiliation: Department of Physiology, Gifu University School of Medicine, 40 Tsukasa-machi, Gifu 500-8705, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Hayashi
authors.forename: Hajime
authors.initials: H
authors.lastname: Imai
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kuwata
authors.forename: Masaru
authors.initials: M
authors.lastname: Sogami
authors.forename: Seiichi
authors.initials: S
authors.lastname: Era
mesh_terms: D000328:Adult; D001793:Blood Preservation / Q000592:standards*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008297:Male; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000592:standards; D012709:Serum Albumin / Q000032:analysis* / Q000378:metabolism / Q000592:standards*; D013696:Temperature; D013997:Time Factors
chemical_list: D004364:Pharmaceutical Preparations; D012709:Serum Albumin; C001702:mercaptoalbumin