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Title: Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap

Abstract

Methodology for performing precursor and neutral loss scans in an RF scanning linear quadrupole ion trap is described and compared to the unconventional ac frequency scan technique. In the RF scanning variant, precursor ions are mass selectively excited by a fixed frequency resonance excitation signal at low Mathieu q while the RF amplitude is ramped linearly to pass ions through the point of excitation such that the excited ion’s m/z varies linearly with time. Ironically, a nonlinear ac frequency scan is still required for ejection of the product ions since their frequencies vary nonlinearly with the linearly varying RF amplitude. In the case of the precursor scan, the ejection frequency must be scanned so that it is fixed on a product ion m/z throughout the RF scan, whereas in the neutral loss scan, it must be scanned to maintain a constant mass offset from the excited precursor ions. Both simultaneous and sequential permutation scans are possible; only the former are demonstrated here. The scans described are performed on a variety of samples using different ionization sources: protonated amphetamine ions generated by nanoelectrospray ionization (nESI), explosives ionized by low-temperature plasma (LTP), and chemical warfare agent simulants sampled from a surface andmore » analyzed with swab touch spray (TS). We lastly conclude that the ac frequency scan variant of these MS/MS scans is preferred due to electronic simplicity. In an accompanying manuscript, we thus describe the implementation of orthogonal double resonance precursor and neutral loss scans on the Mini 12 using constant RF voltage. .« less

Authors:
; ; ; ; ;  [1]
  1. Purdue University, Department of Chemistry (United States)
Publication Date:
OSTI Identifier:
22776896
Resource Type:
Journal Article
Journal Name:
Journal of the American Society for Mass Spectrometry
Additional Journal Information:
Journal Volume: 29; Journal Issue: 7; Other Information: Copyright (c) 2018 American Society for Mass Spectrometry; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1044-0305
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CHEMICAL WARFARE AGENTS; COMPARATIVE EVALUATIONS; EXCITATION; IONIZATION; IONS; MASS; NONLINEAR PROBLEMS; PLASMA; QUADRUPOLES; RADIOWAVE RADIATION; RESONANCE; TRAPS

Citation Formats

Snyder, Dalton T., Szalwinski, Lucas J., Schrader, Robert L., Pirro, Valentina, Hilger, Ryan, and Cooks, R. Graham, E-mail: cooks@purdue.edu. Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap. United States: N. p., 2018. Web. doi:10.1007/S13361-018-1920-3.
Snyder, Dalton T., Szalwinski, Lucas J., Schrader, Robert L., Pirro, Valentina, Hilger, Ryan, & Cooks, R. Graham, E-mail: cooks@purdue.edu. Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap. United States. doi:10.1007/S13361-018-1920-3.
Snyder, Dalton T., Szalwinski, Lucas J., Schrader, Robert L., Pirro, Valentina, Hilger, Ryan, and Cooks, R. Graham, E-mail: cooks@purdue.edu. Sun . "Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap". United States. doi:10.1007/S13361-018-1920-3.
@article{osti_22776896,
title = {Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap},
author = {Snyder, Dalton T. and Szalwinski, Lucas J. and Schrader, Robert L. and Pirro, Valentina and Hilger, Ryan and Cooks, R. Graham, E-mail: cooks@purdue.edu},
abstractNote = {Methodology for performing precursor and neutral loss scans in an RF scanning linear quadrupole ion trap is described and compared to the unconventional ac frequency scan technique. In the RF scanning variant, precursor ions are mass selectively excited by a fixed frequency resonance excitation signal at low Mathieu q while the RF amplitude is ramped linearly to pass ions through the point of excitation such that the excited ion’s m/z varies linearly with time. Ironically, a nonlinear ac frequency scan is still required for ejection of the product ions since their frequencies vary nonlinearly with the linearly varying RF amplitude. In the case of the precursor scan, the ejection frequency must be scanned so that it is fixed on a product ion m/z throughout the RF scan, whereas in the neutral loss scan, it must be scanned to maintain a constant mass offset from the excited precursor ions. Both simultaneous and sequential permutation scans are possible; only the former are demonstrated here. The scans described are performed on a variety of samples using different ionization sources: protonated amphetamine ions generated by nanoelectrospray ionization (nESI), explosives ionized by low-temperature plasma (LTP), and chemical warfare agent simulants sampled from a surface and analyzed with swab touch spray (TS). We lastly conclude that the ac frequency scan variant of these MS/MS scans is preferred due to electronic simplicity. In an accompanying manuscript, we thus describe the implementation of orthogonal double resonance precursor and neutral loss scans on the Mini 12 using constant RF voltage. .},
doi = {10.1007/S13361-018-1920-3},
journal = {Journal of the American Society for Mass Spectrometry},
issn = {1044-0305},
number = 7,
volume = 29,
place = {United States},
year = {2018},
month = {7}
}