Direct observation of hyperpolarization breaking through the spin diffusion barrier



Stern, Quentin, Cousin, Samuel Francois, Mentink-Vigier, Frederic, Pinon, Arthur Cesar, Elliott, Stuart James ORCID: 0000-0002-8726-0635, Cala, Olivier and Jannin, Sami
(2021) Direct observation of hyperpolarization breaking through the spin diffusion barrier. SCIENCE ADVANCES, 7 (18). eabf5735-.

Access the full-text of this item by clicking on the Open Access link.
[img] Text
eabf5735.full.pdf - Published version

Download (2MB) | Preview

Abstract

Dynamic nuclear polarization (DNP) is a widely used tool for overcoming the low intrinsic sensitivity of nuclear magnetic resonance spectroscopy and imaging. Its practical applicability is typically bounded, however, by the so-called "spin diffusion barrier," which relates to the poor efficiency of polarization transfer from highly polarized nuclei close to paramagnetic centers to bulk nuclei. A quantitative assessment of this barrier has been hindered so far by the lack of general methods for studying nuclear polarization flow in the vicinity of paramagnetic centers. Here, we fill this gap and introduce a general set of experiments based on microwave gating that are readily implemented. We demonstrate the versatility of our approach in experiments conducted between 1.2 and 4.2 K in static mode and at 100 K under magic angle spinning (MAS)-conditions typical for dissolution DNP and MAS-DNP-and directly observe the marked dependence of polarization flow on temperature.

Item Type: Article
Uncontrolled Keywords: Biomedical Imaging
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 11 May 2021 08:04
Last Modified: 17 Mar 2024 12:42
DOI: 10.1126/sciadv.abf5735
Open Access URL: https://www.science.org/doi/10.1126/sciadv.abf5735
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3121495