Multidimensional Mapping of Spin-Exchange Optical Pumping in Clinical-Scale Batch-Mode super(129)Xe Hyperpolarizers

• Published in: The journal of physical chemistry. B Vol. 118; no. 18; pp. 4809 - 4816-4809-4816
• Main Authors: Nikolaou, Panayiotis, Coffey, Aaron M, Ranta, Kaili, Walkup, Laura L, Gust, Brogan M, Barlow, Michael J, Rosen, Matthew S, Goodson, Boyd M, Chekmenev, Eduard Y
• Format: Journal Article
• Language: English
• Published: 08.05.2014
• Subjects: Dynamics; Flux; Operating temperature; Optical pumping; Partial pressure; Photons; Polarization; Xenon
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp501493k

We present a systematic, multiparameter study of Rb/ super(129)Xe spin-exchange optical pumping (SEOP) in the regimes of high xenon pressure and photon flux using a 3D-printed, clinical-scale stopped-flow hyperpolarizer. In situ NMR detection was used to study the dynamics of super(129)Xe polarization as a function of SEOP-cell operating temperature, photon flux, and xenon partial pressure to maximize super(129)Xe polarization (P sub(Xe)). P sub(Xe) values of 95 plus or minus 9%, 73 plus or minus 4%, 60 plus or minus 2%, 41 plus or minus 1%, and 31 plus or minus 1% at 275, 515, 1000, 1500, and 2000 Torr Xe partial pressure were achieved. These P sub(Xe) polarization values were separately validated by ejecting the hyperpolarized super(129)Xe gas and performing low-field MRI at 47.5 mT. It is shown that P sub(Xe) in this high-pressure regime can be increased beyond already record levels with higher photon flux and better SEOP thermal management, as well as optimization of the polarization dynamics, pointing the way to further improvements in hyperpolarized super(129)Xe production efficiency.