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Ion Mobility Mass Spectrometry (ion + mobility_mass_spectrometry)

Distribution by Scientific Domains

Chemistry	100%

Selected Abstracts

Peak capacity of ion mobility mass spectrometry: the utility of varying drift gas polarizability for the separation of tryptic peptides

JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2004
Brandon T. Ruotolo
Abstract Ion mobility mass spectrometry (IM-MS) peptide mass mapping experiments were performed using a variety of drift gases (He, N2, Ar and CH4). The drift gases studied cover a range of polarizabilities ((0.2,2.6) × 10,24 cm3) and the peak capacities obtained for tryptic peptides in each gas are compared. Although the different gases exhibit similar peak capacities (5430 (Ar) to 7580 (N2)) in some cases separation selectivity presumably based on peptide conformers (or conformer populations), is observed. For example the drift time profiles observed for some tryptic peptide ions from aldolase (rabbit muscle) show a dependence on drift gas. The transmission of high-mass ions (m/z > 2000) is also influenced by increased scattering cross-section of the more massive drift gases. Consequently the practical peak capacity for IM-MS separation cannot be assumed to be solely a function of resolution and the ability of a gas to distribute signals in two-dimensional space; rather, peak capacity estimates must account for the transmission losses experienced for peptide ions as the drift gas mass increases. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Peak width-mass correlation in CID MS/MS of isomeric oligosaccharides using traveling-wave ion mobility mass spectrometry

JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 10 2009
Tohru Yamagaki
Abstract Isomeric oligosaccharides ,-cyclodextrin (,-CD), glucosyl-,CD (Glc1 -,CD) and maltosyl-,CD (Glc2 -,CD) were analyzed by traveling-wave ion mobility (twIM) mass spectrometry (MS). Their formation of multicharged multimers differed from each other. The ion mobility-mass spectrometry was useful in the self-assembling and complex formation analyses of CD isomers. The drift times of the isomers and their product ions with the same mass were almost the same in collision-induced dissociation (CID) MS/MS. In contrast, the ion mobility peak widths were sensitive to structural differences of the isomeric product ions. The twIM peak width (ms - µs) of the product ions [M , Glcn + H]+ (n = 0 , 6) of ,-CD correlated linearly with their masses (Da); the large and/or long chain product ions had wider peak widths, which were much wider than those from the general diffusion effect. This was a novel and useful ,trend line' to discriminate between the three isomers. Plots of [M , Glc2 , 6 + H]+ of Glc1 -,CD and [M , Glc3 , 6 + H]+ of Glc2 -,CD product ions' plots were on the same trend line as ,-CD. The plots of [M , Glc1 + H]+ of Glc1 -,CD and [M , Glc1, 2 + H]+ of Glc2 -,CD strayed from the ,-CD line; their peak widths were narrower than those of ,-CD. These results indicated that product ions from the chemical species of Glc1 -, CD and Glc2 -,CD retained their CD structure. Analyses of the IM peak widths enable us to elucidate the structures of the product ions. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Peak capacity of ion mobility mass spectrometry: the utility of varying drift gas polarizability for the separation of tryptic peptides

Travelling wave ion mobility mass spectrometry studies of protein structure: biological significance and comparison with X-ray crystallography and nuclear magnetic resonance spectroscopy measurements

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 20 2008
Charlotte A. Scarff
The three-dimensional conformation of a protein is central to its biological function. The characterisation of aspects of three-dimensional protein structure by mass spectrometry is an area of much interest as the gas-phase conformation, in many instances, can be related to that of the solution phase. Travelling wave ion mobility mass spectrometry (TWIMS) was used to investigate the biological significance of gas-phase protein structure. Protein standards were analysed by TWIMS under denaturing and near-physiological solvent conditions and cross-sections estimated for the charge states observed. Estimates of collision cross-sections were obtained with reference to known standards with published cross-sections. Estimated cross-sections were compared with values from published X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy structures. The cross-section measured by ion mobility mass spectrometry varies with charge state, allowing the unfolding transition of proteins in the gas phase to be studied. Cross-sections estimated experimentally for proteins studied, for charge states most indicative of native structure, are in good agreement with measurements calculated from published X-ray and NMR structures. The relative stability of gas-phase structures has been investigated, for the proteins studied, based on their change in cross-section with increase in charge. These results illustrate that the TWIMS approach can provide data on three-dimensional protein structures of biological relevance. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Comparison of flow injection analysis electrospray mass spectrometry and tandem mass spectrometry and electrospray high-field asymmetric waveform ion mobility mass spectrometry and tandem mass spectrometry for the determination of underivatized amino acids

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2006
Margaret McCooeye
Twenty proteinogenic amino acids (AAs) were determined without derivatization using flow injection analysis followed by electrospray ionization mass spectrometry and tandem mass spectrometry (ESI-MS and ESI-MS/MS) and electrospray ionization high-field asymmetric waveform ion mobility mass spectrometry and tandem mass spectrometry (ESI-FAIMS-MS and ESI-FAIMS-MS/MS), in positive and negative ionization modes. Three separate sets of ESI-FAIMS conditions were used for the separation and detection of the 20 AAs. Typically ESI-FAIMS-MS showed somewhat improved sensitivity and significantly better signal-to-noise ratios than ESI-MS mainly due to the elimination of background noise. However, the difference between ESI-FAIMS-MS and ESI-MS/MS was significantly less. ESI-FAIMS was able to partially or completely resolve all the isobaric amino acid overlaps such as leucine, isoleucine and hydroxyproline or lysine and glutamine. Detection limits for the amino acids in ESI-FAIMS-MS mode ranged from 2,ng/mL for proline to 200,ng/mL for aspartic acid. Overall, ESI-FAIMS-MS is the preferred method for the quantitative analysis of AAs in a hydrolyzed yeast matrix. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source]