Rapid polarization of 1 liter of xenon-129 to 10% in 6 minutes with a continuous-flow spin-exchange optical pumping polarizer

Motivation: Rapid hyperpolarized xenon-129 production is essential for hyperpolarized gas MRI studies. Goal(s): To improve hyperpolarized xenon-129 production rates, for rapid on-demand dose production. Approach: A continuous-flow polarizer was optimized for maximum xenon-129 polarization and cryogenic volume recovery at high xenon flow rate (180 ml/min). Results: Maximum xenon-129 polarization of 10.2 ± 1.3 % was measured at 3 bar cell pressure using 3% Xe (86% enriched xenon-129), 10% N2 and 87% He gas mixture. Cryogenic Xe volume recovery was improved by using high cell pressure and a large cold finger. 1 liter of hyperpolarized xenon-129 was produced in 6.1 minutes, to polarization of 9.98%. Impact: The results demonstrate the ability to produce rapid on-demand hyperpolarized xenon-129 doses in large volumes, which will improve clinical workflows for hyperpolarized gas MRI studies.