Total correlation spectroscopy across all NMR-active nuclei by mixing at zero field

Ivan V Zhukov (1, 2) , Alexey S Kiryutin (1, 2) , Fabien Ferrage (3) , Gerd Buntkowsky (4) , Alexandra V Yurkovskaya (1, 2) , Konstantin L Ivanov (1, 2)

1 NSU - Novosibirsk State University
2 SB RAS - International Tomography Center [Novosibirsk, Russia]
3 LBM UMR 7203 - Laboratoire des biomolécules
4 TU Darmstadt - Technische Universität Darmstadt - Technical University of Darmstadt

Multidimensional Nuclear Magnetic Resonance (NMR) is based on the combination of well-established building blocks for polarization transfer. These blocks are used to design correlation experiments through one or a few chemical bonds or through space. Here, we introduce a building block that enables polarization transfer across all NMR-active nuclei in a coupled network of spins: isotropic mixing at Zero and Ultra-Low Field (ZULF). Exploiting mixing under ZULF-NMR conditions, heteronuclear TOtal Correlation SpectroscopY (TOCSY) experiments were developed to highlight coupled spin networks. We demonstrate 1 H-13 C and 1 H-15 N correlations in ZULF-TOCSY spectra of labelled amino acids, which allow one to obtain cross-peaks among all hetero-nuclei belonging to the same coupled network, even when the direct interaction between them is negligible. We also demonstrate the interest of ZULF-TOCSY to analyze complex mixtures on a growth medium of isotope-labelled biomolecules. ZULF-TOCSY enables the quick identification of individual compounds in the mixture by their coupled spin networks. The ZULF-TOCSY method will lead to the development of a new toolbox of experiments to analyze complex mixtures by NMR.

Domaines: Chimie théorique et/ou physique

Ivan V Zhukov, Alexey S Kiryutin, Fabien Ferrage, Gerd Buntkowsky, Alexandra V Yurkovskaya, et al.. Total correlation spectroscopy across all NMR-active nuclei by mixing at zero field. Journal of Physical Chemistry Letters, 2020, 11 (17), pp.7291-7296. ⟨10.1021/acs.jpclett.0c02032⟩. ⟨hal-03098498⟩