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Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
Electron ionization dissociation of singly and multiply charged peptides
Y M Eva Fung1, Christopher M Adams, Roman A Zubarev
1Division of Molecular Biometry, Department of Medicinal Biochemistry and Biophysics, Karolinska Institutet, SE-17 177 Stockholm, Sweden.
Journal of the American Chemical Society
|July 23, 2009
Summary
Electron Ionization Dissociation (EID) is a novel mass spectrometry technique that fragments ions with high efficiency, exceeding 100%. This method is effective for both bottom-up and top-down proteomics analyses.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Proteomics
Background:
- Tandem mass spectrometry is crucial for protein identification and characterization.
- Existing fragmentation techniques have limitations in efficiency and fragmentation patterns.
Purpose of the Study:
- To introduce and characterize a new tandem mass spectrometry technique, Electron Ionization Dissociation (EID).
- To evaluate the efficiency and fragmentation capabilities of EID for proteomics applications.
Main Methods:
- Irradiation of trapped cations [M + nH](n+) with fast electrons (energy > ionization threshold).
- Induction of simultaneous ionization and electronic excitation, leading to fragmentation.
- Analysis of fragment ions, including side-chain losses and backbone cleavage (N-C(alpha) and C-C bonds).
Main Results:
- EID achieves theoretical fragmentation efficiencies potentially exceeding 100%.
- EID produces both c-/z-type (N-C(alpha) cleavage) and a-/x-type (C-C cleavage) fragments.
- The technique is applicable to ions produced by electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI).
Conclusions:
- EID offers a highly efficient fragmentation method for mass spectrometry.
- The technique's versatility makes it suitable for both bottom-up and top-down proteomics.
- EID's ability to incorporate significant energy makes it promising for analyzing complex protein structures.
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