title: Diagnosis of albuminuria by tryptic digestion and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry.
abstract: BACKGROUND
  Matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) mass spectrometry has been successfully used to detect trace albumin in urine for the diagnosis of albuminuria. However, only the monomeric form of albumin was detected with this approach.
  
  
  METHODS
  Trypsin was used to digest urinary albumin and its related compounds in urine to produce characteristic peptides. The digest solution was subsequently analyzed by MALDI-TOF MS to obtain peptide ion signals which were used as diagnostic biomarkers for albuminuria.
  
  
  RESULTS
  The analytical protocol was optimized for efficient digestion and high-performance MALDI-TOF MS analysis. The limit of detection (LOD) of albumin in urine was about 5×10(-7)M.
  
  
  CONCLUSIONS
  Trypsin digestion combined with MALDI-TOF MS analysis is an efficient and simple approach for rapidly diagnosing albuminuria.
authors.affiliation: Department of Cosmetic Applications and Management, Yuh-Ing Junior College of Health Care & Management, Kaohsiung, Taiwan.
authors.forename: Yi-Tzu
authors.initials: YT
authors.lastname: Cho
authors.forename: Chien-Wen
authors.initials: CW
authors.lastname: Chen
authors.forename: Miao-Pei
authors.initials: MP
authors.lastname: Chen
authors.forename: Jia-Lun
authors.initials: JL
authors.lastname: Hu
authors.forename: Hung
authors.initials: H
authors.lastname: Su
authors.forename: Jentaie
authors.initials: J
authors.lastname: Shiea
authors.forename: Wen-Jeng
authors.initials: WJ
authors.lastname: Wu
authors.forename: Deng-Chyang
authors.initials: DC
authors.lastname: Wu
mesh_terms: D000418:Albumins / Q000378:metabolism*; D000419:Albuminuria / Q000175:diagnosis*; D006801:Humans; D057230:Limit of Detection; D010455:Peptides / Q000652:urine; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014357:Trypsin / Q000378:metabolism*
chemical_list: D000418:Albumins; D010455:Peptides; D014357:Trypsin