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Updated: Feb 9, 2026
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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization
Dominik J Kubicki1, Gilles Casano2, Martin Schwarzwälder3
1Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland .
Chemical Science
|June 14, 2018
Summary
New dinitroxide biradicals were tested as polarizing agents for dynamic nuclear polarization NMR. Longer relaxation times and deuteration improved performance, with one radical achieving record enhancements.
Area of Science:
- Chemistry
- Physical Chemistry
- Magnetic Resonance
Background:
- Dynamic Nuclear Polarization (DNP) NMR enhances sensitivity.
- Nitroxide radicals are crucial polarizing agents in DNP.
Purpose of the Study:
- To synthesize and evaluate 37 new dinitroxide biradicals for DNP NMR.
- To correlate radical structure and properties with DNP performance.
Main Methods:
- Cross-effect DNP NMR experiments were conducted at 9.4 T and 100 K.
- Polarizing agents were dissolved in 1,1,2,2-tetrachloroethane (TCE).
- Electron and nuclear spin relaxation times were analyzed.
Main Results:
- DNP performance strongly depends on substituents and relaxation times.
- Longer relaxation times correlated with enhanced DNP signal.
- Deuteration generally improved DNP enhancement but increased build-up time.
- A novel radical demonstrated superior performance under tested conditions.
Conclusions:
- Structural modifications and deuteration are effective strategies for optimizing DNP polarizing agents.
- The newly developed radical represents a significant advancement for DNP NMR applications.
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