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Updated: Jun 14, 2026
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Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
Peptide fragmentation by keV ion-induced dissociation
Sadia Bari1, Ronnie Hoekstra, Thomas Schlathölter
1KVI Atomic and Molecular Physics, University of Groningen, Zernikelaan 25, NL-9747 AA Groningen, The Netherlands. s.bari@rug.nl
Physical Chemistry Chemical Physics : PCCP
|April 1, 2010
Summary
High-energy ions (keV) induce peptide fragmentation, revealing unique side-chain loss patterns useful for identifying peptides. This method offers a novel approach for peptide analysis.
Area of Science:
- Chemical Physics
- Analytical Chemistry
- Biophysics
Background:
- Peptide identification is crucial in proteomics.
- Conventional methods for peptide fragmentation have limitations.
- Understanding ion-molecule interactions is key to developing new analytical tools.
Purpose of the Study:
- To investigate multiple ionization and dissociation of protonated leucine enkephalin using keV ions.
- To demonstrate the potential of keV ions for peptide identification.
- To explore the influence of projectile ion electronic structure on fragmentation patterns.
Main Methods:
- Trapping of protonated leucine enkephalin.
- Irradiation with keV singly and doubly charged ions (H+, He+, He2+).
- Analysis of fragmentation patterns, including side-chain loss and backbone scission.
Main Results:
- Fragmentation patterns show strong peaks due to side-chain loss, distinct from conventional methods.
- Observed fragmentation is explainable by energy deposition via electronic stopping.
- Fragmentation patterns exhibit a dependence on projectile ion electronic structure, linked to electron capture efficiencies.
Conclusions:
- keV ions are a promising tool for future peptide identification.
- The fragmentation mechanism involves electronic stopping and electron capture.
- Projectile ion properties significantly influence peptide dissociation pathways.
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