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Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
Published on: February 19, 2020
Electrospray ionization high-resolution ion mobility spectrometry-mass spectrometry.
1Department of Chemistry, Washington State University, Pullman, Washington 99164-4630.
Analytical Chemistry
|June 8, 2011
Summary
A new hybrid atmospheric pressure ion mobility spectrometer achieves near-diffusion-limited resolving power for ions. This advanced instrument enables rapid analytical separations comparable to liquid chromatography, offering significant improvements for complex analyses.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
- Spectroscopy
Background:
- Ion mobility spectrometry (IMS) is a powerful technique for analyzing ions in the gas phase.
- Traditional atmospheric pressure IMS instruments have limitations in resolving power for complex mixtures.
- Multiply charged ions are common in modern analytical techniques like electrospray ionization (ESI).
Purpose of the Study:
- To describe a novel hybrid atmospheric pressure ion mobility spectrometer (AP-IMS).
- To evaluate the resolving power of this instrument for singly and multiply charged ions.
- To demonstrate the capability of AP-IMS for rapid analytical separations of biomolecules.
Main Methods:
- Development of a hybrid atmospheric pressure ion mobility spectrometer.
- Coupling of an electrospray ionization (ESI) source with a quadrupole mass spectrometer (MS).
- Measurement of gas-phase mobility spectra for mass-identified multiply charged ions.
Main Results:
- The hybrid AP-IMS instrument achieved resolving power approaching the diffusion limit (>200).
- First measurements of gas-phase mobility spectra for mass-identified multiply charged ions reported.
- Baseline separations of multiply charged states of cytochrome c and ubiquitin were achieved, demonstrating enhanced resolving power.
Conclusions:
- The developed hybrid AP-IMS offers significantly improved resolving power over previous instruments.
- Collision cross sections are demonstrably affected by ion charge state.
- This ESI-IMS-MS instrument shows great potential for rapid analytical separations with LC-like resolution.
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