Improved detection of phosphopeptides by negative ion matrix-assisted laser desorption/ionization mass spectrometry using a proton sponge co-matrix

Shu Zhang, Zhongping Yao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

8 Citations (Scopus)


Analysis of phosphopeptides is an important task in proteomic studies. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a technique very commonly used for such a purpose. Analysis of phosphopeptides by MALDI-MS is, however, still a challenging task due to the low ionization efficiency of phosphopeptides. In this study, we reported that by using a proton sponge 1,8-bis(dimethyl-amino)naphthalene (DMAN) as a co-matrix, detection of phosphopeptides by negative ion MALDI-MS could be greatly improved. Combination of DMAN with another matrix 6-aza-2-thiothymine (ATT) and additive diammonium hydrogen citrate (DHC) allowed much lower limit of detection, significantly reduced signal suppression effects and improved position-to-position reproducibility for detection of phosphopeptides by negative ion MALDI-MS. Potential applications of the matrix system in qualification of phosphopeptides and analysis of proteolytic digests of phosphorylated proteins were also demonstrated in this study.
Original languageEnglish
Pages (from-to)77-82
Number of pages6
JournalAnalytica Chimica Acta
Publication statusPublished - 20 Jan 2012


  • Mass spectrometry
  • Matrix
  • Negative ion
  • Phosphopeptides
  • Proton sponge

ASJC Scopus subject areas

  • Analytical Chemistry
  • Environmental Chemistry
  • Biochemistry
  • Spectroscopy

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