Application of Tandem Enrichment Strategy by MALDI-TOF MS in Phosphorylated Proteomics

KeyWord:desalting  IMAC  matrix-assisted laser desorption-ionization time of flight mass spectrometry(MALDI-TOF MS)  phosphopeptides  tandem enrichment

Abstract:

      A scheme was presented for the tandem purification of phosphopeptide using desalting prior to immobilized metal ion affinity chromatography(IMAC).Both C18 tip and the cerium(¢ô)-modified chitosan material(Ce-MCM) were used in the desalting experiments.GMA-co-SR454/Iron(¢ó)-IDA was synthesized,and used as an excellent phosphopetides enrichment material.They were applied to selectively capture the phosphopeptides in standards and human serum.Results demonstrated that C18/IMAC and Ce-MCM/IMAC have different performances because of their hydrophobic or hydrophilic properties.Ce-MCM/IMAC tandem strategy notably decreased the complexity of peptides,and yielded a far greater coverage for phosphopeptides than single IMAC.