Reconversion of Parahydrogen Gas in Surfactant-Coated Glass NMR Tubes.

ABSTRACT: The application of parahydrogen gas to enhance the magnetic resonance signals of a diversity of chemical species has increased substantially in the last decade. Parahydrogen is prepared by lowering the temperature of hydrogen gas in the presence of a catalyst; this enriches the para spin isomer beyond its normal abundance of 25% at thermal equilibrium. Indeed, parahydrogen fractions that approach unity can be attained at sufficiently low temperatures. Once enriched, the gas will revert to its normal isomeric ratio over the course of hours or days, depending on the surface chemistry of the storage container. Although parahydrogen enjoys long lifetimes when stored in aluminum cylinders, the reconversion rate is significantly faster in glass containers due to the prevalence of paramagnetic im

SUBMITTER: Chimenti RV 

PROVIDER: S-EPMC10004819 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature