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Updated: Aug 13, 2026
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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
"Fast excitation" CID in a quadrupole ion trap mass spectrometer
J Murrell1, D Despeyroux, S A Lammert
1Dstl, Detection Department, Porton Down, Salisbury, Wiltshire, United Kingdom.
Summary
Collision-induced dissociation (CID) using fast excitation offers a new method for ion fragmentation in mass spectrometry. This technique achieves similar results to conventional CID but with shorter excitation times.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
Background:
- Collision-induced dissociation (CID) is a standard technique in quadrupole ion trap mass spectrometry.
- Conventional CID uses small amplitude excitation at the ion's secular frequency for extended periods.
Purpose of the Study:
- To investigate the use of large amplitude, short duration voltage excitations for ion fragmentation.
- To compare the efficacy of this "fast excitation" CID with conventional resonance excitation CID.
Main Methods:
- Utilized leucine enkephalin as a model compound.
- Simulated ion motion within the ion trap using ITSIM software.
- Applied large amplitude voltage excitations for short durations.
Main Results:
- "Fast excitation" CID produced identical fragmentation information to conventional CID.
- Similar internal energy deposition was observed between the two methods.
- Higher excitation rate and fragmentation during the ion cooling phase were noted for "fast excitation" CID.
Conclusions:
- "Fast excitation" CID is an effective alternative to conventional CID, offering comparable fragmentation results.
- The technique is applicable to larger molecules, such as proteins, as demonstrated with myoglobin.
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