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Title: Dynamic Collision-Induced Dissociation (DCID) in a Quadrupole Ion Trap Using a Two-Frequency Excitation Waveform: II. Effects of Frequency Spacing and Scan Rate

Abstract

Dynamic CID of selected precursor ions is achieved by the application of a two-frequency excitation waveform to the end-cap electrodes during the mass instability scan of a quadrupole ion trap mass spectrometer (QIT-MS). The time period normally allotted for resonance excitation and collisional cooling of the trapped ion are excluded and fragmentation instead takes place simultaneously with the mass acquisition scan. This new method permits a shorter scanning time when compared to conventional on-resonance CID. When the excitation waveform consists of two closely-spaced frequencies, the relative phase-relationship of the two frequencies plays a critical role in the fragmentation dynamics. However, at wider frequency spacings (>8 kHz) these phase effects are diminished, while maintaining the efficacy of closely-spaced excitation frequencies. The fragmentation efficiencies and energetics of n-butylbenzene and tetraalanine are studied under different experimental conditions and the results are compared at various scan rate parameters between 0.1 and 1.0 ms/Th. Although faster scan rates reduce the analysis time, the maximum observed fragmentation efficiencies rarely exceed 30%, compared to values in excess of 50% achieved at slower scan rates. The internal energies calculated from the simulations of n-butylbenzene at fast scan rates are ~4 eV for most experimental conditions, while at slowmore » scan rates internal energies above 5.5 eV are observed for a wide range of conditions. Extensive ITSIM simulations support the observation that slowing the scan rate has a similar effect on fragmentation as widening the frequency spacing between the two excitation frequencies. Both approaches generally enhance CID efficiencies and make fragmentation less dependent upon the relative phase angle between the excitation waveform and the ion motion. This could be useful for optimizing the CID efficiencies for a wide range of precursor ion mass-to-charge ratios.« less

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
921387
Report Number(s):
PNNL-SA-57059
Journal ID: ISSN 1044-0305; JAMSEF; TRN: US200804%%727
DOE Contract Number:  
AC05-76RL01830
Resource Type:
Journal Article
Journal Name:
Journal of the American Society for Mass Spectrometry, 18(11):2017-2025
Additional Journal Information:
Journal Volume: 18; Journal Issue: 11; Journal ID: ISSN 1044-0305
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DISSOCIATION; EXCITATION; MASS SPECTROMETERS; QUADRUPOLES; RESONANCE; WAVE FORMS; TRAPS; IONS; FREQUENCY DEPENDENCE; AROMATICS; AMINO ACIDS; ion trap mass spectrometry; collision induced dissociation; collisional activation

Citation Formats

Laskay, Unige A., Collin, Olivier L., Nichol, Brad, Jackson, Glen P., Pasilis, Sofie P., and Duckworth, Doug C. Dynamic Collision-Induced Dissociation (DCID) in a Quadrupole Ion Trap Using a Two-Frequency Excitation Waveform: II. Effects of Frequency Spacing and Scan Rate. United States: N. p., 2007. Web. doi:10.1016/j.jasms.2007.08.014.
Laskay, Unige A., Collin, Olivier L., Nichol, Brad, Jackson, Glen P., Pasilis, Sofie P., & Duckworth, Doug C. Dynamic Collision-Induced Dissociation (DCID) in a Quadrupole Ion Trap Using a Two-Frequency Excitation Waveform: II. Effects of Frequency Spacing and Scan Rate. United States. doi:10.1016/j.jasms.2007.08.014.
Laskay, Unige A., Collin, Olivier L., Nichol, Brad, Jackson, Glen P., Pasilis, Sofie P., and Duckworth, Doug C. Thu . "Dynamic Collision-Induced Dissociation (DCID) in a Quadrupole Ion Trap Using a Two-Frequency Excitation Waveform: II. Effects of Frequency Spacing and Scan Rate". United States. doi:10.1016/j.jasms.2007.08.014.
@article{osti_921387,
title = {Dynamic Collision-Induced Dissociation (DCID) in a Quadrupole Ion Trap Using a Two-Frequency Excitation Waveform: II. Effects of Frequency Spacing and Scan Rate},
author = {Laskay, Unige A. and Collin, Olivier L. and Nichol, Brad and Jackson, Glen P. and Pasilis, Sofie P. and Duckworth, Doug C.},
abstractNote = {Dynamic CID of selected precursor ions is achieved by the application of a two-frequency excitation waveform to the end-cap electrodes during the mass instability scan of a quadrupole ion trap mass spectrometer (QIT-MS). The time period normally allotted for resonance excitation and collisional cooling of the trapped ion are excluded and fragmentation instead takes place simultaneously with the mass acquisition scan. This new method permits a shorter scanning time when compared to conventional on-resonance CID. When the excitation waveform consists of two closely-spaced frequencies, the relative phase-relationship of the two frequencies plays a critical role in the fragmentation dynamics. However, at wider frequency spacings (>8 kHz) these phase effects are diminished, while maintaining the efficacy of closely-spaced excitation frequencies. The fragmentation efficiencies and energetics of n-butylbenzene and tetraalanine are studied under different experimental conditions and the results are compared at various scan rate parameters between 0.1 and 1.0 ms/Th. Although faster scan rates reduce the analysis time, the maximum observed fragmentation efficiencies rarely exceed 30%, compared to values in excess of 50% achieved at slower scan rates. The internal energies calculated from the simulations of n-butylbenzene at fast scan rates are ~4 eV for most experimental conditions, while at slow scan rates internal energies above 5.5 eV are observed for a wide range of conditions. Extensive ITSIM simulations support the observation that slowing the scan rate has a similar effect on fragmentation as widening the frequency spacing between the two excitation frequencies. Both approaches generally enhance CID efficiencies and make fragmentation less dependent upon the relative phase angle between the excitation waveform and the ion motion. This could be useful for optimizing the CID efficiencies for a wide range of precursor ion mass-to-charge ratios.},
doi = {10.1016/j.jasms.2007.08.014},
journal = {Journal of the American Society for Mass Spectrometry, 18(11):2017-2025},
issn = {1044-0305},
number = 11,
volume = 18,
place = {United States},
year = {2007},
month = {11}
}