Generalization of an Open Dynamically Harmonized Cell for Ultrahigh FT ICR Resolution
Anton Lioznov1, Evgeny Nikolaev1
1Center of Life Science, Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow121205Russia.
Journal of the American Society for Mass Spectrometry
|October 17, 2022
Summary
Fourier transform ion cyclotron resonance (FT ICR) mass spectrometry achieves high resolution. An open cell design improves vacuum, but may slightly alter electric potential, potentially limiting resolving power.
Area of Science:
- Analytical Chemistry
- Physical Chemistry
Background:
- Fourier transform ion cyclotron resonance (FT ICR) mass spectrometry offers superior resolving power.
- The dynamically harmonized measuring cell enhances resolution to over 10^7 at 7 T.
- Theoretical models predict a linear relationship between magnetic field strength and resolving power.
Purpose of the Study:
- Investigate the discrepancy between theoretical resolving power and experimental results in FT ICR mass spectrometry.
- Evaluate the impact of improved vacuum conditions on resolving power.
- Assess the influence of cell geometry on electric potential distribution and overall performance.
Main Methods:
- Utilized a modified open dynamically harmonized measuring cell for FT ICR mass spectrometry.
- Analyzed the effect of improved pumping conditions on ion behavior within the cell.
- Compared experimental resolving power with theoretical predictions under varying magnetic fields.
Main Results:
- Experimental resolving power did not proportionally increase with magnetic field strength as predicted by theory.
- An open cell modification improved vacuum conditions, addressing a potential limitation.
- Deviations in electric potential distribution within the open cell may limit achievable resolving power.
Conclusions:
- Insufficient vacuum was a suspected limitation for resolving power in closed cells.
- The open cell design enhances vacuum but introduces electric potential deviations.
- Further optimization of cell geometry is needed to fully realize the potential of high magnetic fields in FT ICR mass spectrometry.
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