title: Derivatization of peptides as quaternary ammonium salts for sensitive detection by ESI-MS.
abstract: A series of model peptides in the form of quaternary ammonium salts at the N-terminus was efficiently prepared by the solid-phase synthesis. Tandem mass spectrometric analysis of the peptide quaternary ammonium derivatives was shown to provide sequence confirmation and enhanced detection. We designed the 2-(1,4-diazabicyclo[2.2.2] octylammonium)acetyl quaternary ammonium group which does not suffer from neutral losses during MS/MS experiments. The presented quaternization of 1,4-diazabicyclo[2.2.2]octane (DABCO) by iodoacetylated peptides is relatively easy and compatible with standard solid-phase peptide synthesis. This methodology offers a novel sensitive approach to analyze peptides and other compounds.
authors.affiliation: Faculty of Chemistry, University of Wrocław, Wrocław, Poland.
authors.forename: Marzena
authors.initials: M
authors.lastname: Cydzik
authors.forename: Magdalena
authors.initials: M
authors.lastname: Rudowska
authors.forename: Piotr
authors.initials: P
authors.lastname: Stefanowicz
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Szewczuk
mesh_terms: D057230:Limit of Detection; D009842:Oligopeptides / Q000737:chemistry*; D010879:Piperazines / Q000737:chemistry; D055550:Protein Stability; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D009842:Oligopeptides; D010879:Piperazines; D000644:Quaternary Ammonium Compounds; C007306:triethylenediamine