15N Hyperpolarization of Imidazole-15N2 for Magnetic Resonance pH Sensing via SABRE-SHEATH.


Journal Article

15N nuclear spins of imidazole-15N2 were hyperpolarized using NMR signal amplification by reversible exchange in shield enables alignment transfer to heteronuclei (SABRE-SHEATH). A 15N NMR signal enhancement of ∼2000-fold at 9.4 T is reported using parahydrogen gas (∼50% para-) and ∼0.1 M imidazole-15N2 in methanol:aqueous buffer (∼1:1). Proton binding to a 15N site of imidazole occurs at physiological pH (pKa ∼ 7.0), and the binding event changes the 15N isotropic chemical shift by ∼30 ppm. These properties are ideal for in vivo pH sensing. Additionally, imidazoles have low toxicity and are readily incorporated into a wide range of biomolecules. 15N-Imidazole SABRE-SHEATH hyperpolarization potentially enables pH sensing on scales ranging from peptide and protein molecules to living organisms.

Full Text

Duke Authors

Cited Authors

  • Shchepin, RV; Barskiy, DA; Coffey, AM; Theis, T; Shi, F; Warren, WS; Goodson, BM; Chekmenev, EY

Published Date

  • June 2016

Published In

Volume / Issue

  • 1 / 6

Start / End Page

  • 640 - 644

PubMed ID

  • 27379344

Pubmed Central ID

  • 27379344

Electronic International Standard Serial Number (EISSN)

  • 2379-3694

International Standard Serial Number (ISSN)

  • 2379-3694

Digital Object Identifier (DOI)

  • 10.1021/acssensors.6b00231


  • eng