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Updated: Oct 12, 2025
10:54
Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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Protonation tuned dipolar order mediated 1H→13C cross-polarization for dissolution-dynamic nuclear polarization
Stuart J Elliott1, Quentin Stern1, Olivier Cala1
1Univ. Lyon, CNRS, ENS Lyon, UCBL, Université de Lyon, CRMN UMR 5280, 69100, Villeurbanne, France.
Solid State Nuclear Magnetic Resonance
|November 25, 2021
Summary
Polarization transfer from 1H to 13C spins is enhanced by increasing solvent protonation in dissolution-dynamic nuclear polarization (dDNP) experiments. This method offers a faster, more efficient way to boost 13C signals, especially with deuterated molecules.
Area of Science:
- Nuclear Magnetic Resonance Spectroscopy
- Physical Chemistry
Background:
- Dynamic Nuclear Polarization (DNP) enhances NMR sensitivity by transferring polarization from electron spins to nuclear spins.
- Dissolution-Dynamic Nuclear Polarization (dDNP) is a technique used to hyperpolarize nuclear spins for enhanced NMR signal detection.
- Dipolar order mediated polarization transfer is an advanced method for transferring spin polarization.
Purpose of the Study:
- To investigate the influence of sample composition on dipolar order mediated polarization transfer under dDNP conditions.
- To understand the role of glassing matrix protonation level and molecular deuteration in 1H→13C polarization transfer.
- To optimize parameters for efficient polarization transfer in dDNP experiments.
Main Methods:
- Utilizing optimized shaped radiofrequency pulses and molecular modifications for polarization transfer.
- Systematically varying the protonation level of the DNP glass constituents.
- Employing deuterated molecular derivatives for comparative analysis.
- Experimental demonstrations using [1-13C]sodium acetate.
Main Results:
- Increased solvent protonation significantly shortens 13C signal build-up time.
- Deuteration of nearby methyl groups negatively impacts 1H→13C transfer, especially at low sample protonation.
- Higher solvent protonation levels lead to faster and more efficient dipolar order governed polarization transfer.
- Polarization transfer efficiencies of deuterated molecules can be improved with adequate solvent protonation.
Conclusions:
- Sample formulation, particularly solvent protonation level, critically influences dipolar order mediated polarization transfer efficiency in dDNP.
- Optimizing solvent protonation is key to enhancing polarization transfer rates and signal intensities.
- This study provides insights into optimizing dDNP protocols for sensitive NMR applications.
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