Zero-field nuclear magnetic resonance of chemically exchanging systems

Barskiy, Danila A.
Taylen, Michael C. D.
Marco-Rius, Irene
Kurhanewicz, John
Vigneron, Daniel B.
Çıkrıkcı, Sevil
Aydoğdu, Ayça
Reh, Moritz
Pravdivtsev, Andrey N.
Hoevener, Jan-Bernd
Blanchard, John W.
Wu, Teng
Budker, Dmitry
Pines, Alexander
Zero- to ultralow-field (ZULF) nuclear magnetic resonance (NMR) is an emerging tool for precision chemical analysis. In this work, we study dynamic processes and investigate the influence of chemical exchange on ZULF NMR J-spectra. We develop a computational approach that allows quantitative calculation of J-spectra in the presence of chemical exchange and apply it to study aqueous solutions of [N-15]ammonium ((NH4+)-N-15) as a model system. We show that pH-dependent chemical exchange substantially affects the J-spectra and, in some cases, can lead to degradation and complete disappearance of the spectral features. To demonstrate potential applications of ZULF NMR for chemistry and biomedicine, we show a ZULF NMR spectrum of [2-C-13]pyruvic acid hyperpolarized via dissolution dynamic nuclear polarization (dDNP). We foresee applications of affordable and scalable ZULF NMR coupled with hyperpolarization to study chemical exchange phenomena in vivo and in situations where high-field NMR detection is not possible to implement.


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Citation Formats
D. A. Barskiy et al., “Zero-field nuclear magnetic resonance of chemically exchanging systems,” NATURE COMMUNICATIONS, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: