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Updated: Jul 10, 2026
08:01
A Microfluidic Approach for the Study of Ice and Clathrate Hydrate Crystallization
Published on: August 18, 2022
Room-temperature hyperpolarization via polarization relay through rapid cocrystallization
Haruki Sato1, Makoto Negoro2,3,4, Akinori Kagawa2,3
1Graduate School of Science and Technology for Innovation, Tokushima University Tokushima 770-8506 Japan.
Chemical Science
|July 9, 2026
Summary
We developed HYCOR, a novel polarization-relay strategy, to transfer hyperpolarization from triplet dynamic nuclear polarization (DNP) to target molecules. This method overcomes limitations of traditional DNP, enabling enhanced 13C polarization of difficult-to-polarize compounds like pyruvic acid.
Area of Science:
- Solid-state chemistry
- Magnetic resonance imaging
- Quantum chemistry
Background:
- Hyperpolarization techniques significantly enhance NMR/MRI sensitivity.
- Triplet dynamic nuclear polarization (DNP) is limited to solids with long relaxation times.
- Efficient polarization transfer to diverse molecules remains a challenge.
Purpose of the Study:
- Introduce HYCOR (HYperpolarization via COcrystallization and Relay) for efficient polarization transfer.
- Enable room-temperature 13C hyperpolarization of target molecules.
- Demonstrate HYCOR using pyruvic acid as a benchmark.
Main Methods:
- Utilized triplet DNP to hyperpolarize a mediator (pentacene in picolinamide).
- Employed rapid cocrystallization to transfer polarization to target molecules (pyruvic acid).
- Analyzed polarization loss kinetics and factors influencing HYCOR efficiency.
Main Results:
- Achieved room-temperature 13C polarization of pyruvic acid via HYCOR.
- Demonstrated significant solid-state (0.012%) and dissolved-state (0.0028%) polarization.
- Identified kinetic competition between cocrystallization and relaxation as key to efficiency.
Conclusions:
- HYCOR successfully extends triplet DNP to target molecules with short relaxation times.
- This polarization-relay strategy offers a new pathway for hyperpolarizing diverse compounds.
- HYCOR has potential applications in fields requiring enhanced NMR/MRI sensitivity.
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