Linear mass scans in quadrupole ion traps using the inverse Mathieu q scan
Dalton T Snyder1, Christopher J Pulliam1, R Graham Cooks2
1Department of Chemistry and Center for Analytical Instrumentation Development, Purdue University, West Lafayette, IN, 47907, USA.
Rapid Communications in Mass Spectrometry : RCM
|August 7, 2016
Summary
A new inverse Mathieu q scan method simplifies mass calibration in quadrupole ion traps. This secular frequency scanning technique offers a linear mass scale, improving mass range and power efficiency for mass spectrometry.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Spectroscopy
Background:
- Secular frequency scanning in quadrupole ion traps typically involves complex nonlinear calibration.
- Existing methods require intricate procedures to correlate mass-to-charge ratio with time.
Purpose of the Study:
- To introduce a simplified secular frequency scanning method for quadrupole ion traps.
- To achieve a linear mass-to-charge ratio versus time relationship, simplifying calibration.
Main Methods:
- Developed an "inverse Mathieu q scan" method for secular frequency scanning.
- Scanned the supplementary AC frequency to ensure mass-to-charge linearity with time.
- Investigated the influence of RF and AC amplitudes and scan rates on performance.
Main Results:
- Demonstrated excellent mass spectral linearity using the inverse Mathieu q scan.
- Observed that RF amplitude controls scan range and rate; AC amplitude and scan rate affect mass resolution.
- Confirmed that mass calibration remains linear despite amplitude changes, simplifying data analysis.
Conclusions:
- The inverse Mathieu q scan provides a linear mass scale, simplifying quadrupole ion trap operation.
- This method enhances mass range and power efficiency.
- Paves the way for AC waveform-based mass spectrometers for ion manipulation.
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