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Updated: May 5, 2026

Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
Long-lived nuclear spin states in methyl groups and quantum-rotor-induced polarization
Benno Meier1, Jean-Nicolas Dumez, Gabriele Stevanato
1School of Chemistry, University of Southampton , SO17 1BJ Southampton, U.K.
Abstract:
Substances containing rapidly rotating methyl groups may exhibit long-lived states (LLSs) in solution, with relaxation times substantially longer than the conventional spin-lattice relaxation time T1. The states become long-lived through rapid internal rotation of the CH3 group, which imposes an approximate symmetry on the fluctuating nuclear spin interactions. In the case of very low CH3 rotational barriers, a hyperpolarized LLS is populated by thermal equilibration at liquid helium temperature. Following dissolution, cross-relaxation of the hyperpolarized LLS, induced by heteronuclear dipolar couplings, generates strongly enhanced antiphase NMR signals. This mechanism explains the NMR signal enhancements observed for (13)C-γ-picoline (Icker, M.; Berger, S. J. Magn. Reson. 2012, 219, 1-3).
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