Measurement and Theory of Gas-Phase Ion Mobility Shifts Resulting from Isotopomer Mass Distribution Changes.
Anal Chem
; 93(45): 14966-14975, 2021 11 16.
Article
in En
| MEDLINE
| ID: mdl-34726890
ABSTRACT
The unanticipated discovery of recent ultra-high-resolution ion mobility spectrometry (IMS) measurements revealing that isotopomersâcompounds that differ only in the isotopic substitution sitesâcan be separated has raised questions as to the physical basis for their separation. A study comparing IMS separations for two isotopomer sets in conjunction with theory and simulations accounting for ion rotational effects provides the first-ever prediction of rotation-mediated shifts. The simulations produce observable mobility shifts due to differences in gas-ion collision frequency and translational-to-rotational energy transfer. These differences can be attributed to distinct changes in the moment of inertia and center of mass between isotopomers. The simulations are in broad agreement with the observed experiments and consistent with relative mobility differences between isotopomers. These results provide a basis for refining IMS theory and a new foundation to obtain additional structural insights through IMS.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ion Mobility Spectrometry
Language:
En
Journal:
Anal Chem
Year:
2021
Type:
Article
Affiliation country:
United States