title: Dual track time-of-flight mass spectrometry for peptide quantification with matrix-assisted laser desorption/ionization.
abstract: BACKGROUND
  Previously, we reported a method (Anal. Chem. 2012, 84, 10332) for peptide quantification based on matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). In the method, the peptide-to-matrix ion abundance ratio was utilized. Implementation of the method with a commercial MALDI-TOF can be somewhat inconvenient because matrix-derived ions are routinely deflected away to avoid detector saturation. A solution for this inconvenience is required.
  
  
  METHODS
  We installed a detector to acquire the TOF spectrum of the ions thrown away to avoid detector saturation. By sending the matrix- and peptide-derived ions along two different tracks and detecting them with different detectors, the inconvenience mentioned above could be avoided.
  
  
  RESULTS
  Excellent linearity of the calibration curves obtained by the dual track TOF spectrometry is demonstrated. The method also allows for the acquisition of the tandem mass spectrum of a selected peptide, which can be useful for its identification.
  
  
  CONCLUSIONS
  We devised the dual track MALDI-TOF MS method to avoid detector saturation and demonstrated that the quantification and identification of peptides can be performed simultaneously.
authors.affiliation: Department of Chemistry, Seoul National University, Seoul, 151-747, Korea.
authors.forename: Yong Jin
authors.initials: YJ
authors.lastname: Bae
authors.forename: Jeong Hee
authors.initials: JH
authors.lastname: Moon
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Kim
mesh_terms: D002138:Calibration; D016014:Linear Models; D010455:Peptides / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013696:Temperature
chemical_list: D010455:Peptides