Remarkable Levels of ¹⁵N Polarization Delivered through SABRE into Unlabeled Pyridine, Pyrazine, or Metronidazole Enable Single Scan NMR Quantification at the mM Level.

ABSTRACT: While many drugs and metabolites contain nitrogen, harnessing their diagnostic ¹⁵N NMR signature for their characterization is underutilized because of inherent detection difficulties. Here, we demonstrate how precise ultralow field signal amplification by reversible exchange (±0.2 mG) in conjunction parahydrogen and an iridium precatalyst of the form IrCl(COD)(NHC) with the coligand d₉-benzylamine allows the naturally abundant ¹⁵N NMR signatures of pyridine, pyrazine, metronidazole, and acetonitrile to be readily detected at 9.4 T in single NMR observations through >50% ¹⁵N polarization levels. These signals allow for rapid and precise reagent quantification via a response that varies linearly over the 2-70 mM concentration range.

SUBMITTER: Fekete M 

PROVIDER: S-EPMC7277555 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature