TY - JOUR

T1 - Low-Cost High-Pressure Clinical-Scale 50% Parahydrogen Generator Using Liquid Nitrogen at 77 K

AU - Chapman, Benjamin

AU - Joalland, Baptiste

AU - Meersman, Collier

AU - Ettedgui, Jessica

AU - Swenson, Rolf E.

AU - Krishna, Murali C.

AU - Nikolaou, Panayiotis

AU - Kovtunov, Kirill V.

AU - Salnikov, Oleg G.

AU - Koptyug, Igor V.

AU - Gemeinhardt, Max E.

AU - Goodson, Boyd M.

AU - Shchepin, Roman V.

AU - Chekmenev, Eduard Y.

N1 - Publisher Copyright: © 2021 American Chemical Society Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/6/22

Y1 - 2021/6/22

N2 - We report on a robust and low-cost parahydrogen generator design employing liquid nitrogen as a coolant. The core of the generator consists of catalyst-filled spiral copper tubing, which can be pressurized to 35 atm. Parahydrogen fraction >48% was obtained at 77 K with three nearly identical generators using paramagnetic hydrated iron oxide catalysts. Parahydrogen quantification was performed on the fly via benchtop NMR spectroscopy to monitor the signal from residual orthohydrogen-parahydrogen is NMR silent. This real-time quantification approach was also used to evaluate catalyst activation at up to 1.0 standard liter per minute flow rate. The reported inexpensive device can be employed for a wide range of studies employing parahydrogen as a source of nuclear spin hyperpolarization. To this end, we demonstrate the utility of this parahydrogen generator for hyperpolarization of concentrated sodium [1-13C]pyruvate, a metabolic contrast agent under investigation in numerous clinical trials. The reported pilot optimization of SABRE-SHEATH (signal amplification by reversible exchange-shield enables alignment transfer to heteronuclei) hyperpolarization yielded 13C signal enhancement of over 14,000-fold at a clinically relevant magnetic field of 1 T corresponding to approximately 1.2% 13C polarization - if near 100% parahydrogen would have been employed, the reported value would be tripled to 13C polarization of 3.5%.

AB - We report on a robust and low-cost parahydrogen generator design employing liquid nitrogen as a coolant. The core of the generator consists of catalyst-filled spiral copper tubing, which can be pressurized to 35 atm. Parahydrogen fraction >48% was obtained at 77 K with three nearly identical generators using paramagnetic hydrated iron oxide catalysts. Parahydrogen quantification was performed on the fly via benchtop NMR spectroscopy to monitor the signal from residual orthohydrogen-parahydrogen is NMR silent. This real-time quantification approach was also used to evaluate catalyst activation at up to 1.0 standard liter per minute flow rate. The reported inexpensive device can be employed for a wide range of studies employing parahydrogen as a source of nuclear spin hyperpolarization. To this end, we demonstrate the utility of this parahydrogen generator for hyperpolarization of concentrated sodium [1-13C]pyruvate, a metabolic contrast agent under investigation in numerous clinical trials. The reported pilot optimization of SABRE-SHEATH (signal amplification by reversible exchange-shield enables alignment transfer to heteronuclei) hyperpolarization yielded 13C signal enhancement of over 14,000-fold at a clinically relevant magnetic field of 1 T corresponding to approximately 1.2% 13C polarization - if near 100% parahydrogen would have been employed, the reported value would be tripled to 13C polarization of 3.5%.

UR - http://www.scopus.com/inward/record.url?scp=85108716669&partnerID=8YFLogxK

U2 - 10.1021/acs.analchem.1c00716

DO - 10.1021/acs.analchem.1c00716

M3 - Article

C2 - 34102835

AN - SCOPUS:85108716669

VL - 93

SP - 8476

EP - 8483

JO - Analytical Chemistry

JF - Analytical Chemistry

SN - 0003-2700

IS - 24

ER -