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Updated: Jul 3, 2026
11:18
A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer (SMPS-ICPMS)
Published on: July 11, 2017
Predicting optimal resolving power for ambient pressure ion mobility spectrometry
Abu B Kanu1, Molly M Gribb, Herbert H Hill
1Department of Chemistry, Prairie View A&M University, Prairie View, Texas 77446-0519, USA.
Analytical Chemistry
|August 8, 2008
Summary
Optimizing Ion Mobility Spectrometry (IMS) voltage is crucial for maximizing resolving power, which depends on the compound and ion pulse width. A new equation helps predict realistic resolving powers for specific conditions.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
Background:
- Ion Mobility Spectrometry (IMS) theory suggests resolving power increases with drift tube voltage.
- Practical IMS applications show an optimal voltage exists, beyond which resolving power declines.
Purpose of the Study:
- To investigate the voltage-dependent resolving power of IMS.
- To introduce a conditional resolving power equation for practical estimations.
- To compare theoretical, conditional, and measured resolving powers for environmental contaminants.
Main Methods:
- Determined optimal voltage for resolving power in a small IMS instrument.
- Developed and applied a "conditional" resolving power equation.
- Measured resolving powers (Rd, Rc, Rm) for four environmental contaminants.
Main Results:
- Optimal IMS voltage is dependent on the compound and initial ion pulse width.
- Conditional resolving power equation provides realistic approximations.
- Measured resolving power efficiency ranged from 56-74%.
Conclusions:
- Standard diffusion theory is insufficient for predicting optimal IMS performance.
- The conditional resolving power equation and efficiency metrics are valuable for instrument design and operation.
- The developed IMS achieved detection limits from 18 pptv to 80 ppbv for contaminants.
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