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A Slowly Relaxing Rigid Biradical for Efficient Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy: Expeditious Characterization of Functional Group Manipulation in Hybrid Materials
Zagdoun A., Casano G., Ouari O., Lapadula G., Rossini A. J., Lelli M., Baffert M., Gajan D., Veyre L., Maas W. E. et al
Journal of the American Chemical Society 134, 4 (2012) Volume: 134 Issue: 4 Pages: 2284-2291 DOI: - http://hal.archives-ouvertes.fr/hal-00699587
Article in peer-reviewed journal
Chemical Sciences/Analytical chemistry
A Slowly Relaxing Rigid Biradical for Efficient Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy: Expeditious Characterization of Functional Group Manipulation in Hybrid Materials
Alexandre Zagdoun 1, Gilles Casano 2, Olivier Ouari 2, Giuseppe Lapadula 3, Aaron J. Rossini 1, Moreno Lelli 1, Mathieu Baffert 4, David Gajan 3, Laurent Veyre 4, Werner E. Maas 5, Mélanie Rosay 5, Ralph T Weber 5, Chloé Thieuleux 4, Christophe Coperet 3, Anne Lesage 1, Paul Tordo 2, Lyndon Emsley () 1
1:  Institut des Sciences Analytiques (ISA)
http://isa.univ-lyon1.fr/
Université de Lyon – CNRS : UMR5280 – Université Claude Bernard - Lyon I – École Normale Supérieure - Lyon
5 rue de la Doua, 69100 Villeurbanne
France
2:  Laboratoire Chimie Provence (LCP)
http://lc-provence.fr
Université de Provence - Aix-Marseille I – CNRS : UMR6264
Université de Provence LCP, Equipe Instrumentation et Reactivité Atmosphérique (case 29) 3, place V Hugo 13331 Marseille Cedex 3
France
3:  Laboratory of Inorganic Chemistry
Eidgenössische Technische Hochschule Zürich (ETH Zürich)
Department of Chemistry, ETH Zürich, CH-8093, Zürich, Switzerland
Switzerland
4:  Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2)
http://www.c2p2-cpe.com/
CNRS : UMR5265 – CPE LYON – Université Claude Bernard - Lyon I
43, Bd. du 11 Novembre 1918, Villeurbanne F-69616,
France
5:  Bruker BioSpin Corporation
Bruker BioSpin Corporation
Billerica, Massachusetts 01821, United States
United States
Centre de RMN à très hauts champs
A new nitroxide-based biradical having a long electron spin-lattice relaxation time (T-1e) has been developed as an exogenous polarization source for DNP solid-state NMR experiments. The performance of this new biradical is demonstrated on hybrid silica-based mesostructured materials impregnated with 1,1,2,2-tetrachloroethane radical containing solutions, as well as in frozen bulk solutions, yielding DNP enhancement factors (epsilon) of over 100 at a magnetic field of 9.4 T and sample temperatures of similar to 100 K. The effects of radical concentration on the DNP enhancement factors and on the overall sensitivity enhancements (Sigma(dagger)) are reported. The relatively high DNP efficiency of the biradical is attributed to an increased T-1e, which enables more effective saturation of the electron resonance. This new biradical is shown to outperform the polarizing agents used so far in DNP surface-enhanced NMR spectroscopy of materials, yielding a 113-fold increase in overall sensitivity for silicon-29 CPMAS spectra as compared to conventional NMR experiments at room temperature. This results in a reduction in experimental times by a factor >12 700, making the acquisition of C-13 and N-15 one- and two-dimensional NMR spectra at natural isotopic abundance rapid (hours). It has been used here to monitor a series of chemical reactions carried out on the surface functionalities of a hybrid organic-silica material.
English

Journal of the American Chemical Society (J Am Chem Soc)
Publisher American Chemical Society
ISSN 0002-7863 (eISSN : 1520-5126)
international
2012-02-01
134
4
Volume: 134 Issue: 4 Pages: 2284-2291 DOI:

SOLID-STATE NMR – HETEROGENEOUS CATALYSTS – MEMBRANE – SILICA – DNP – SOLVENTS

EU PIIF-GA-2010-274574 ; EQUIPEX ANR-10-EQPX-47-01 ; ETH Zurich
Project Id EQUIPEX ANR-10-EQPX-47-01
Acronyme EU PIIF-GA-2010-274574