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Updated: Aug 30, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Recoupling of residual dipolar couplings in single-domain polymer-stabilized liquid crystals undergoing magic-angle
Jean-François Trempe1, Alexei Denisov, Kalle Gehring
1Department of Biochemistry, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, Que, Canada H3G 1Y6. jean-francois.trempe@bioch.ox.ac.uk
Abstract:
Measurement of dipolar couplings, chemical shift anisotropies, and quadrupole couplings in oriented media such as liquid crystals are of great importance for extraction of structural parameters in biological macromolecules. Here, we introduce a new technique, SAD-REDOR, that consists of recoupling heteronuclear dipolar couplings in molecules dissolved in a single-domain liquid crystal or other oriented medium through the combined use of magic-angle spinning and rotor-synchronized radiofrequency pulses. This application of the REDOR pulse sequence to oriented media offers several advantages such as selectivity over the type of coupling recovered and tunable scaling of the interaction. The effectiveness of the technique is demonstrated both theoretically and experimentally, using the recently developed polyacrylamide-stabilized Pf1 phage medium and 15N-labeled benzamide as the aligned molecule.
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