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Published on: November 17, 2019
A proteomics grade electron transfer dissociation-enabled hybrid linear ion trap-orbitrap mass spectrometer
Graeme C McAlister1, W Travis Berggren, Jens Griep-Raming
1Department of Chemistry and Biomolecular Chemistry, University of Wisconsin, Madison, WI 53706, USA.
Journal of Proteome Research
|July 11, 2008
Summary
We modified a hybrid mass spectrometer for negative chemical ionization (NCI) to perform electron transfer dissociation (ETD) on proteins. This advancement enhances protein sequence analysis, offering new opportunities for proteomics research.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Proteomics
Background:
- Electron Transfer Dissociation (ETD) is a powerful technique for peptide and protein sequencing.
- Existing mass spectrometry platforms may have limitations in efficiently performing ETD, particularly for complex samples.
- The integration of specific ion sources and detection methods is crucial for advancing proteomic analysis.
Purpose of the Study:
- To modify a quadrupole linear ion trap-orbitrap hybrid (QLT-orbitrap) mass spectrometer for enhanced ETD analysis.
- To implement a negative chemical ionization (NCI) source for generating fluoranthene radical anions for ETD.
- To evaluate the performance and applications of the modified instrument in protein sequence analysis.
Main Methods:
- Modification of a QLT-orbitrap mass spectrometer to incorporate an NCI source.
- Generation of fluoranthene radical anions for ion/ion reactions within the QLT.
- Mass-to-charge (m/z) analysis of ETD product ions using either the QLT or the orbitrap.
- Parametric optimization of anion transport and evaluation of ETD figures of merit.
Main Results:
- Successful integration of an NCI source for stable, robust, and intense anion beam generation (4-8 ms injection time).
- Demonstration of ETD product ion analysis with high sensitivity (QLT) and high resolution/accuracy (orbitrap).
- Successful application to various proteomic analyses, including complex peptide mixtures, PTM site identification, quantitation, and intact protein analysis.
Conclusions:
- The ETD-enabled orbitrap represents a significant advancement in protein sequence analysis technologies.
- This modified instrument provides new opportunities for comprehensive proteomic studies.
- The system offers flexibility in analyzing ETD products for speed, sensitivity, resolution, and accuracy.
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