Wide mass range trapping using a 7-T internal source matrix-assisted laser desorption/ionization Fourier transform
Sasa M Miladinovic1, Scott A Robotham, Charles L Wilkins
1Chemistry and Biochemistry Department, University of Arkansas, Fayetteville, AR 72701, USA.
Analytical and Bioanalytical Chemistry
|August 30, 2008
Summary
A new wide mass range trapping method using matrix-assisted laser desorption-Fourier transform mass spectrometry (MALDI-FTMS) shows promise for analyzing ion mixtures. While effective for equimolar samples, its accuracy decreases with compositional changes.
Area of Science:
- Analytical Chemistry
- Spectroscopy
Background:
- Matrix-assisted laser desorption-Fourier transform mass spectrometry (MALDI-FTMS) is a powerful analytical technique.
- Accurate analysis of complex ion mixtures remains a challenge.
Purpose of the Study:
- To evaluate a novel wide mass range trapping method for MALDI-FTMS.
- To assess the method's applicability in MS/MS experiments.
Main Methods:
- A cubic cell with ramped potentials was used to trap ions over a wide mass range.
- Ion ejection and collision-induced dissociation were employed for MS/MS analysis.
- Experiments were conducted using a 7.2-T unshielded magnet.
Main Results:
- The new trapping method demonstrated good performance for equimolar poly(ethylene glycol) (PEG) mixtures, yielding peak area ratios consistent with known compositions.
- Results were comparable to a previously described integral method and MALDI-time-of-flight (TOF) mass spectrometry.
- All tested methods showed reduced accuracy when PEG compositions were altered, though the integral method performed relatively better.
Conclusions:
- The evaluated wide mass range trapping method is a viable approach for MALDI-FTMS analysis of ion mixtures.
- Further optimization is needed to improve accuracy for non-equimolar samples.
- The method shows potential for advanced MS/MS applications.
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