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05:47
Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
Published on: February 19, 2020
Extractive electrospray ionization mass spectrometry-enhanced sensitivity using an ion funnel
Lukas Meier1, Christian Berchtold, Stefan Schmid
1Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
Analytical Chemistry
|January 10, 2012
Summary
Ion funnels significantly boost extractive electrospray ionization (EESI) sensitivity. This study demonstrates a >3-fold improvement in detection limits for complex samples using ambient pressure ion funnels.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Ion Optics
Background:
- Electrodynamic ion funnels enhance electrospray ionization (ESI) sensitivity by over 2 orders of magnitude in intermediate pressure regions (1-30 Torr).
- Extractive electrospray ionization (EESI) is a robust technique for analyzing complex matrices with numerous compounds.
Purpose of the Study:
- To investigate the use of an ambient pressure ion funnel to enhance EESI sensitivity.
- To improve the limit of detection (LOD) for analytes analyzed via EESI.
Main Methods:
- Directly spraying analytes into an ambient pressure ion funnel coupled with EESI.
- Evaluating the sensitivity enhancement using standard EESI experiments as a baseline.
- Testing the method with pharmaceutical compounds (atenolol, salbutamol) and a controlled substance (cocaine).
Main Results:
- The ion funnel coupled with EESI achieved a sensitivity enhancement.
- The limit of detection for atenolol, salbutamol, and cocaine was improved by more than 3 orders of magnitude compared to standard EESI.
Conclusions:
- Ambient pressure ion funnels are effective for enhancing EESI sensitivity.
- This approach offers a significant improvement in detecting analytes in complex samples.
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