A Versatile Compact Parahydrogen Membrane Reactor

Abstract

We introduce a Spin Transfer Automated Reactor (STAR) that produces continuous parahydrogen induced polarization (PHIP), which is stable for hours to days. We use the PHIP variant called signal amplification by reversible exchange (SABRE), which is particularly well suited to produce continuous hyperpolarization. The STAR is operated in conjunction with benchtop (1.1 T) and high field (9.4 T) NMR magnets, highlighting the versatility of this system to operate with any NMR or MRI system. The STAR uses semipermeable membranes to efficiently deliver parahydrogen into solutions at nano to milli Tesla fields, which enables 1 H, 13 C, and 15 N hyperpolarization on a large range of substrates including drugs and metabolites. The unique features of the STAR are leveraged for important applications, including continuous hyperpolarization of metabolites, desirable for examining steady-state metabolism in vivo, as well as for continuous RASER signals suitable for the investigation of new physics.

Through-Space Multinuclear Magnetic Resonance Signal Enhancement Induced by Parahydrogen and Radiofrequency Amplification by Stimulated Emission of Radiation

“…The radiofrequency amplification by stimulated emission of radiation (RASER) effect was previously shown for optically pumped 3 He and 129 Xe and in DNP experiments. − Recently, RASER was also demonstrated in SABRE and PHIP experiments. − The detailed description of the RASER theory can be found elsewhere . In brief, RASER is a result of a nonlinear interaction of negatively hyperpolarized nuclear spins with the resonant circuit of the NMR probe.…”

Order‐Unity 13C Nuclear Polarization of [1‐13C]Pyruvate in Seconds and the Interplay of Water and SABRE Enhancement

“…All results reported here were obtained using a clinicalscale SABRE-SHEATH hyperpolarizer (Figure 1c shows the diagram of the gas manifold and key components within the PHIP hyperpolarizer), the experimental design of which will be described elsewhere as part of our long-standing efforts to share best laboratory practices of parahydrogen hyperpolarizers' designs with the scientific community. [39][40][41]…”

Rapid 13C Hyperpolarization of the TCA Cycle Intermediate α-Ketoglutarate via SABRE-SHEATH

“…The key advantages of the SABRE-SHEATH hyperpolarization approach are the low cost of HP hardware (<$20k) and a rapid (∼1 min) hyperpolarization process. 36 Moreover, this HP technique does not modify the to-be-HP substrate. 37,38 Since HP [1- 13 C]pyruvate is the leading HP contrast agent, the reader is reminded that d-DNP performs hyperpolarization of [1-13 C]pyruvic acid, which is chemically modified to sodium [1- 13 C]pyruvate via a neutralization reaction.…”

“…In 2019, Duckett and co-workers demonstrated the feasibility of SABRE-SHEATH hyperpolarization of [1- 13 C]­pyruvate using DMSO as a coligand, but 13 C polarization levels were limited to 1.85%. , The addition of DMSO leads to the formation of SABRE-active complex and 3b (Scheme ); note that axial positions are not exchanging on the time scale of the SABRE-SHEATH experiment, and therefore, only complex 3b undergoes an effectively reversible exchange with the HP substrate. The key advantages of the SABRE-SHEATH hyperpolarization approach are the low cost of HP hardware (<$20k) and a rapid (∼1 min) hyperpolarization process . Moreover, this HP technique does not modify the to-be-HP substrate. , Since HP [1- 13 C]­pyruvate is the leading HP contrast agent, the reader is reminded that d-DNP performs hyperpolarization of [1- 13 C]­pyruvic acid, which is chemically modified to sodium [1- 13 C]­pyruvate via a neutralization reaction.…”