An improved measurement of isotopic ratios by high resolution mass spectrometry.
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ABSTRACT:
SUBMITTER: Ilchenko S
PROVIDER: S-EPMC3893058 | biostudies-literature | 2013 Feb
REPOSITORIES: biostudies-literature
Publications
An improved measurement of isotopic ratios by high resolution mass spectrometry.
Ilchenko Serguei S Previs Stephen F SF Rachdaoui Nadia N Willard Belinda B McCullough Arthur J AJ Kasumov Takhar T
Journal of the American Society for Mass Spectrometry 20130103 2
The study of protein kinetics requires an accurate measurement of isotopic ratios of peptides. Although Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometers yield accurate mass measurements of analytes, the isotopologue ratios are consistently lower than predicted. Recently, we demonstrated that the magnitude of the spectral error in the FT-ICR mass spectrometer is proportional to the scan duration of ions. Here, we present a novel isotopic ratio extrapolation (IRE) method for o ...[more]
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