Optimization of a quadrupole ion storage trap as a source for time-of-flight mass spectrometry

• Published in: Journal of mass spectrometry. Vol. 47; no. 1; pp. 41 - 48
• Main Authors: Dangi, Beni B., Ervin, Kent M.
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-01-2012; Wiley
• Subjects: Analytical chemistry; Chemistry; Exact sciences and technology; mass resolution; quadrupole ion trap; reflectron; Spectrometric and optical methods; tandem mass spectrometry; time of flight; time of flight; Mass resolution; Tandem mass spectrometry; Ion trap; reflectron; Time of flight method; quadrupole ion trap; Mass spectrometry; Electrostatic mirror; Optimization; Quadrupole spectrometer
• ISSN: 1076-5174; 1096-9888
• DOI: 10.1002/jms.2024

Designs of a quadrupole ion trap (QIT) as a source for time‐of‐flight (TOF) mass spectrometry are evaluated for mass resolution, ion trapping, and laser activation of trapped ions. Comparisons are made with the standard hyperbolic electrode ion trap geometry for TOF mass analysis in both linear and reflectron modes. A parallel‐plate design for the QIT is found to give significantly improved TOF mass spectrometer performance. Effects of ion temperature, trapped ion cloud size, mass, and extraction field on mass resolution are investigated in detail by simulation of the TOF peak profiles. Mass resolution (m/Δm) values of several thousand are predicted even at room temperature with moderate extraction fields for the optimized design. The optimized design also allows larger radial ion collection size compared with the hyperbolic ion trap, without compromising the mass resolution. The proposed design of the QIT also improves the ion–laser interaction volume and photon collection efficiency for fluorescence measurements on trapped ions. Copyright © 2011 John Wiley & Sons, Ltd.