화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.118, No.18, 4809-4816, 2014
Multidimensional Mapping of Spin-Exchange Optical Pumping in Clinical-Scale Batch-Mode Xe-129 Hyperpolarizers
We present a systematic, multiparameter study of Rb/Xe-129 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 Xe-129 polarization as a function of SEOP-cell operating temperature, photon flux, and xenon partial pressure to maximize Xe-129 polarization (P-Xe). P-Xe values of 95 +/- 9%, 73 +/- 4%, 60 +/- 2%, 41 +/- 1%, and 31 +/- 1% at 275, 515, 1000, 1500, and 2000 Torr Xe partial pressure were achieved. These P-Xe polarization values were separately validated by ejecting the hyperpolarized Xe-129 gas and performing low-field MRI at 47.5 mT. It is shown that P-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 Xe-129 production efficiency.