Stretch-induced ordering of prochiral dimethyl sulfoxide in anisotropic hydrogels analysed by ¹H and ²H nuclear magnetic resonance
Author(s)
Elliott, Stuart J
Kuchel, Philip W
Eykyn, Thomas R
Type
Journal Article
Abstract
Nuclear spins in small molecules dissolved in stretched hydrogels typically have population-averaged residual interactions. The nuclear magnetic resonance (NMR) spectra of these systems often show additional peaks and splittings compared with free solutions. Residual dipolar couplings (RDCs) and quadrupolar couplings (RQCs) are observed for guest 1H and 2H nuclear spins, respectively. Dimethyl sulfoxide (DMSO) is an exquisitely sensitive probe of such biologically relevant environments since it is prochiral and becomes effectively chiral when embedded in anisotropic gelatin-based hydrogels. Measured 1H RDCs and 2H RQCs were used to estimate bond order parameters over a wide range of stretching extents. At the largest extent of stretching, the 2H splittings were −73.0 and −9.4 Hz, similar to those found for guest molecules in liquid crystals. Inhomogeneous line broadening of the 2H resonances was related to the size of the RQC due to a spatial distribution of RQCs, which was revealed using a one-dimensional slice selective imaging experiment along the stretching direction. 1H NMR spectra exhibited homogeneous line broadening, with resonance integrals that indicated concealed multiplet structure. Understanding molecular bond ordering in mechanically oriented environments provides a conceptual framework for investigating more complex systems including zeolites and those found in vivo.
Date Issued
2025-01-02
Date Acceptance
2024-10-01
Citation
ChemPhysChem, 2025, 26 (1)
ISSN
1439-4235
Publisher
Wiley
Journal / Book Title
ChemPhysChem
Volume
26
Issue
1
Copyright Statement
© 2024 The Authors. ChemPhysChem published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/39382848
Subjects
ALIGNMENT
anisotropic hydrogels
Chemistry
Chemistry, Physical
COUPLINGS
DEUTERIUM NMR
dipolar/quadrupolar splittings
ENANTIOTOPIC DISCRIMINATION
H-1/H-2 nuclear magnetic resonance
H-2 imaging
METHYL
MOLECULAR-DYNAMICS
Physical Sciences
Physics
Physics, Atomic, Molecular & Chemical
prochiral DMSO
PROTEINS
RELAXATION
RESOLUTION
Science & Technology
S-Me bond order parameters
SPECTRA
Publication Status
Published
Coverage Spatial
Germany
Article Number
e202400731
Date Publish Online
2024-10-09