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arXiv · 1807.00223

Scalable Dissolution-Dynamic Nuclear Polarization with Rapid Transfer of a Polarized Solid

Karel Kouřil·Hana Kouřilová·Samuel Bartram·Malcolm H. Levitt·Benno Meier
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Abstract

In dissolution-dynamic nuclear polarization, nuclear spins are hyperpolarized at cryogenic temperatures using radicals and microwave irradiation. The hyperpolarized solid is dissolved with hot solvent and the solution is transferred to a secondary magnet where strongly enhanced magnetic resonance signals are observed. Here we present a method for transferring the hyperpolarized solid. A bullet containing the frozen, hyperpolarized sample is ejected using pressurized helium gas, and shot into a receiving structure in the secondary magnet, where the bullet is retained and the polarized solid is dissolved rapidly. The transfer takes approximately 70 ms. A solenoid, wound along the entire transfer path ensures adiabatic transfer and limits radical-induced low-field relaxation. The method is fast and scalable towards small volumes suitable for high-resolution nuclear magnetic resonance spectroscopy while maintaining high concentrations of the target molecule. Polarization levels of approximately 30% have been observed for 1-$^{\sf 13}$C-labelled pyruvic acid in solution.

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Karel Kouřil, Hana Kouřilová, Samuel Bartram, Malcolm H. Levitt, Benno Meier. 2018-06-30. Scalable Dissolution-Dynamic Nuclear Polarization with Rapid Transfer of a Polarized Solid. https://doi.org/10.1038/s41467-019-09726-5

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