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Controlling charge states of large ions
M Scalf1, M S Westphall, J Krause
1Department of Chemistry, University of Wisconsin, Madison, WI 53706-1396, USA.
Science (New York, N.Y.)
|January 8, 1999
Summary
Controlled reduction of ion charge in electrospray ionization (ESI) simplifies mass spectra. This charge reduction technique enhances the analysis of complex mixtures using ESI mass spectrometry.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Physical Chemistry
Background:
- Electrospray ionization (ESI) is a widely used technique for ionizing molecules in the gas phase.
- Conventional ESI often produces ions with multiple charges, leading to complex mass spectra.
- Analyzing complex mixtures with conventional ESI-MS can be challenging due to spectral complexity.
Purpose of the Study:
- To develop a method for reducing the charge state of ions produced by electrospray ionization.
- To simplify mass spectra obtained from ESI-MS analysis.
- To facilitate the analysis of complex mixtures using ESI-MS.
Main Methods:
- Exposure of electrospray aerosol to a bipolar ionizing gas.
- Controlled reduction of ion charge state to predominantly singly charged species.
- Analysis of resulting ions using an orthogonal time-of-flight mass spectrometer.
Main Results:
- Generation of predominantly singly charged ions from the ESI process.
- Obtained mass spectra were significantly simplified compared to conventional ESI spectra.
- Demonstrated a decrease in spectral complexity.
Conclusions:
- Controlled charge reduction of ESI ions effectively simplifies mass spectra.
- The developed method enhances the analysis of complex mixtures by ESI mass spectrometry.
- This technique offers a valuable tool for improving ESI-MS applications.
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