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Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps
Published on: August 17, 2017
Low mass cutoff evasion with q(z) value optimization in ion trap
Yung-Hun Yang1, Kwangwon Lee, Kyoung-Soon Jang
1School of Chemical and Biological Engineering and Interdisciplinary Program for Biochemical Engineering and Biotechnology, Institute of Bioengineering, Seoul National University, Seoul 110-744, Republic of Korea.
Analytical Biochemistry
|May 21, 2009
Summary
Optimizing the q(z) value in ion trap mass spectrometry overcomes the low mass cutoff (LMCO) limitation. This allows for enhanced peptide analysis using collision-induced dissociation (CID) without instrumental changes.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Mass Spectrometry
Background:
- Ion traps offer high resolution, sensitivity, and multistage mass analysis (MS(n)).
- Multiple fragmentation analysis aids peptide sequencing and structural elucidation.
- Collision-induced dissociation (CID) in ion traps is limited by a low mass cutoff (LMCO).
Purpose of the Study:
- To overcome the LMCO limitation in ion trap mass spectrometry for iTRAQ analysis.
- To optimize the q(z) value for improved tandem mass spectrometry (MS/MS) performance.
Main Methods:
- Optimization of the q(z) value, which relates to AC radio frequency voltage in MS/MS events.
- Application of optimized parameters to ion trap analysis, specifically for iTRAQ workflows.
Main Results:
- Successful mitigation of the LMCO inherent in CID-based ion trap analysis.
- Demonstration of a practical method for enhancing peptide analysis without requiring new instrumentation.
Conclusions:
- Optimizing the q(z) value is an effective strategy to circumvent LMCO in ion traps.
- This approach facilitates broader application of ion trap MS/MS, including iTRAQ, for detailed biomolecular analysis.
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