Molecular hydrogen and catalytic combustion in the production of hyperpolarized ^sup 83^Kr and ^sup 129^Xe MRI contrast agents

Hyperpolarized (hp) ...Kr is a promising MRI contrast agent for the diagnosis of pulmonary diseases affecting the surface of the respiratory zone. However, the distinct physical properties of ...Kr that enable unique MRI contrast also complicate the production of hp ...Kr. This work presents a previ...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2016-03, Vol.113 (12), p.3164
Main Authors: Rogers, Nicola J, Hill-Casey, Fraser, Stupic, Karl F, Six, Joseph S, Lesbats, Clémentine, Rigby, Sean P, Fraissard, Jacques, Pavlovskaya, Galina E, Meersmann, Thomas
Format: Article
Language:English
Subjects:
Catalysis
Chemical elements
Hydrogen
Molecular biology
NMR
Nuclear magnetic resonance
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Hyperpolarized (hp) ...Kr is a promising MRI contrast agent for the diagnosis of pulmonary diseases affecting the surface of the respiratory zone. However, the distinct physical properties of ...Kr that enable unique MRI contrast also complicate the production of hp ...Kr. This work presents a previously unexplored approach in the generation of hp ...Kr that can likewise be used for the production of hp ...Xe. Molecular nitrogen, typically used as buffer gas in spin-exchange optical pumping (SEOP), was replaced by molecular hydrogen without penalty for the achievable hyperpolarization. In this particular study, the highest obtained nuclear spin polarizations were P = 29% for ...Kr and P = 63% for ...Xe. The results were reproduced over many SEOP cycles despite the laser-induced on-resonance formation of rubidium hydride (RbH). Following SEOP, the H2 was reactively removed via catalytic combustion without measurable losses in hyperpolarized spin state of either ...Kr or ...Xe. Highly spin-polarized ...Kr can now be purified for the first time, to our knowledge, to provide high signal intensity for the advancement of in vivo hp ...Kr MRI. More generally, a chemical reaction appears as a viable alternative to the cryogenic separation process, the primary purification method of hp ...Xe for the past 2 1/2 decades. The inherent simplicity of the combustion process will facilitate hp ...Xe production and should allow for on-demand continuous flow of purified and highly spin-polarized ...Xe. (ProQuest: ... denotes formulae/symbols omitted.)
ISSN:0027-8424
1091-6490