1
|
Delage-Laurin L, Palani RS, Golota N, Mardini M, Ouyang Y, Tan KO, Swager TM, Griffin RG. Overhauser Dynamic Nuclear Polarization with Selectively Deuterated BDPA Radicals. J Am Chem Soc 2021; 143:20281-20290. [PMID: 34813311 PMCID: PMC8805148 DOI: 10.1021/jacs.1c09406] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The Overhauser effect (OE), commonly observed in NMR spectra of liquids and conducting solids, was recently discovered in insulating solids doped with the radical 1,3-bisdiphenylene-2-phenylallyl (BDPA). However, the mechanism of polarization transfer in OE-DNP in insulators is yet to be established, but hyperfine coupling of the radical to protons in BDPA has been proposed. In this paper we present a study that addresses the role of hyperfine couplings via the EPR and DNP measurements on some selectively deuterated BDPA radicals synthesized for this purpose. Newly developed synthetic routes enable selective deuteration at orthogonal positions or perdeuteration of the fluorene moieties with 2H incorporation of >93%. The fluorene moieties were subsequently used to synthesize two octadeuterated BDPA radicals, 1,3-[α,γ-d8]-BDPA and 1,3-[β,δ-d8]-BDPA, and a BDPA radical with perdeuterated fluorene moieties, 1,3-[α,β,γ,δ-d16]-BDPA. In contrast to the strong positive OE enhancement observed in degassed samples of fully protonated h21-BDPA (ε ∼ +70), perdeuteration of the fluorenes results in a negative enhancement (ε ∼ -13), while selective deuteration of α- and γ-positions (aiso ∼ 5.4 MHz) in BDPA results in a weak negative OE enhancement (ε ∼ -1). Furthermore, deuteration of β- and δ-positions (aiso ∼ 1.2 MHz) results in a positive OE enhancement (ε ∼ +36), albeit with a reduced magnitude relative to that observed in fully protonated BDPA. Our results clearly show the role of the hyperfine coupled α and γ 1H spins in the BDPA radical in determining the dominance of the zero and double-quantum cross-relaxation pathways and the polarization-transfer mechanism to the bulk matrix.
Collapse
Affiliation(s)
- Léo Delage-Laurin
- Institute for Soldier Nanotechnologies, Cambridge, Massachusetts 02139, United States
| | | | | | | | | | | | - Timothy M Swager
- Institute for Soldier Nanotechnologies, Cambridge, Massachusetts 02139, United States
| | | |
Collapse
|
2
|
Li Y, Chaklashiya R, Takahashi H, Kawahara Y, Tagami K, Tobar C, Han S. Solid-state MAS NMR at ultra low temperature of hydrated alanine doped with DNP radicals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 333:107090. [PMID: 34717278 DOI: 10.1016/j.jmr.2021.107090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/04/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Magic angle spinning (MAS) nuclear magnetic resonance (NMR) experiments at ultra low temperature (ULT) (≪ 100 K) have demonstrated clear benefits for obtaining large signal sensitivity gain and probing spin dynamics phenomena at ULT. ULT NMR is furthermore a highly promising platform for solid-state dynamic nuclear polarization (DNP). However, ULT NMR is not widely used, given limited availability of such instrumentation from commercial sources. In this paper, we present a comprehensive study of hydrated [U-13C]alanine, a standard bio-solid sample, from the first commercial 14.1 Tesla NMR spectrometer equipped with a closed-cycle helium ULT-MAS system. The closed-cycle helium MAS system provides precise temperature control from 25 K to 100 K and stable MAS from 1.5 kHz to 12 kHz. The 13C CP-MAS NMR of [U-13C]alanine showed 400% signal gain at 28 K compared with at 100 K. The large sensitivity gain results from the Boltzmann factor, radio frequency circuitry quality factor improvement, and the suppression of its methyl group rotation at ULT. We further observed that the addition of organic biradicals widely used for solid-state DNP significantly shortens the 1H T1 spin lattice relaxation time at ULT, without further broadening the 13C spectral linewidth compared to at 90 K. The mechanism of 1H T1 shortening is dominated by the two-electron-one-nucleus triple flip transition underlying the Cross Effect mechanism, widely relied upon to drive solid-state DNP. Our experimental observations suggest that the prospects of MAS NMR and DNP under ULT conditions established with a closed-cycle helium MAS system are bright.
Collapse
Affiliation(s)
- Yuanxin Li
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Raj Chaklashiya
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | | | | | - Kan Tagami
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Celeste Tobar
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Songi Han
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States; Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, United States.
| |
Collapse
|
3
|
Equbal A, Tagami K, Han S. Pulse-Shaped Dynamic Nuclear Polarization under Magic-Angle Spinning. J Phys Chem Lett 2019; 10:7781-7788. [PMID: 31790265 DOI: 10.1021/acs.jpclett.9b03070] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Dynamic nuclear polarization (DNP) under magic-angle spinning (MAS) is transforming the scope of solid-state NMR by enormous signal amplification through transfer of polarization from electron spins to nuclear spins. Contemporary MAS-DNP exclusively relies on monochromatic continuous-wave (CW) irradiation of the electron spin resonance. This limits control on electron spin dynamics, which renders the DNP process inefficient, especially at higher magnetic fields and non cryogenic temperatures. Pulse-shaped microwave irradiation of the electron spins is predicted to overcome these challenges but hitherto has never been implemented under MAS. Here, we debut pulse-shaped microwave irradiation using arbitrary-waveform generation (AWG) which allows controlled recruitment of a greater number of electron spins per unit time, favorable for MAS-DNP. Experiments and quantum mechanical simulations demonstrate that pulse-shaped DNP is superior to CW-DNP for mixed radical system, especially when the electron spin resonance is heterogeneously broadened and/or when its spin-lattice relaxation is fast compared to the MAS rotor period, opening new prospects for MAS-DNP.
Collapse
Affiliation(s)
- Asif Equbal
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Kan Tagami
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
| | - Songi Han
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , California 93106 , United States
- Department of Chemical Engineering , University of California , Santa Barbara , California 93106 , United States
| |
Collapse
|
4
|
Li Y, Equbal A, Tagami K, Han S. Electron spin density matching for cross-effect dynamic nuclear polarization. Chem Commun (Camb) 2019; 55:7591-7594. [PMID: 31165810 PMCID: PMC6597276 DOI: 10.1039/c9cc03499d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new design principle for a mixed broad (TEMPO) and narrow (Trityl) line radical to boost the dynamic nuclear polarization efficiency is electron spin density matching, suggesting a polarizing agent of one Trityl tethered to at least two TEMPO moieties.
Collapse
Affiliation(s)
- Yuanxin Li
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, USA.
| | | | | | | |
Collapse
|
5
|
Alaniva N, Saliba EP, Sesti EL, Judge PT, Barnes AB. Electron Decoupling with Chirped Microwave Pulses for Rapid Signal Acquisition and Electron Saturation Recovery. Angew Chem Int Ed Engl 2019; 58:7259-7262. [DOI: 10.1002/anie.201900139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/01/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Nicholas Alaniva
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Edward P. Saliba
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Erika L. Sesti
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Patrick T. Judge
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
- Department of Biochemistry, Biophysics, and Biology Washington University in St. Louis School of Medicine 660 S. Euclid Ave St Louis MO 63110 USA
| | - Alexander B. Barnes
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| |
Collapse
|
6
|
Alaniva N, Saliba EP, Sesti EL, Judge PT, Barnes AB. Electron Decoupling with Chirped Microwave Pulses for Rapid Signal Acquisition and Electron Saturation Recovery. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201900139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Nicholas Alaniva
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Edward P. Saliba
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Erika L. Sesti
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| | - Patrick T. Judge
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
- Department of Biochemistry, Biophysics, and Biology Washington University in St. Louis School of Medicine 660 S. Euclid Ave St Louis MO 63110 USA
| | - Alexander B. Barnes
- Department of Chemistry Washington University in St. Louis One Brookings Drive St. Louis MO 63130 USA
| |
Collapse
|
7
|
Viger-Gravel J, Berruyer P, Gajan D, Basset JM, Lesage A, Tordo P, Ouari O, Emsley L. Frozen Acrylamide Gels as Dynamic Nuclear Polarization Matrices. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jasmine Viger-Gravel
- Institut des Sciences et Ingénierie Chimiques; Ecole Polytechnique Fédérale de Lausanne (EPFL); 1015 Lausanne Switzerland
| | - Pierrick Berruyer
- Université de Lyon; Institut des Sciences Analytiques (UMR 5280 CNRS/UCBL/ENS Lyon), Centre de RMN à Très Hauts Champs; 69100 Villeurbanne France
| | - David Gajan
- Université de Lyon; Institut des Sciences Analytiques (UMR 5280 CNRS/UCBL/ENS Lyon), Centre de RMN à Très Hauts Champs; 69100 Villeurbanne France
| | - Jean-Marie Basset
- King Abdullah University of Science and Technology (KAUST); KAUST Catalysis Center (KCC); Thuwal 23955-6900 Saudi Arabia
| | - Anne Lesage
- Université de Lyon; Institut des Sciences Analytiques (UMR 5280 CNRS/UCBL/ENS Lyon), Centre de RMN à Très Hauts Champs; 69100 Villeurbanne France
| | - Paul Tordo
- Aix Marseille Uni, CNRS, ICR UMR 7273; 13397 Marseille France
| | - Olivier Ouari
- Aix Marseille Uni, CNRS, ICR UMR 7273; 13397 Marseille France
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques; Ecole Polytechnique Fédérale de Lausanne (EPFL); 1015 Lausanne Switzerland
| |
Collapse
|
8
|
Salnikov ES, Abel S, Karthikeyan G, Karoui H, Aussenac F, Tordo P, Bechinger B, Ouari O. Dynamic Nuclear Polarization/Solid-State NMR Spectroscopy of Membrane Polypeptides: Free-Radical Optimization for Matrix-Free Lipid Bilayer Samples. Chemphyschem 2017; 18:2103-2113. [PMID: 28574169 DOI: 10.1002/cphc.201700389] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/24/2017] [Indexed: 01/07/2023]
Abstract
Dynamic nuclear polarization (DNP) boosts the sensitivity of NMR spectroscopy by orders of magnitude and makes investigations previously out of scope possible. For magic-angle-spinning (MAS) solid-state NMR spectroscopy studies, the samples are typically mixed with biradicals dissolved in a glass-forming solvent and are investigated at cryotemperatures. Herein, we present new biradical polarizing agents developed for matrix-free samples such as supported lipid bilayers, which are systems widely used for the investigation of membrane polypeptides of high biomedical importance. A series of 11 biradicals with different structures, geometries, and physicochemical properties were comprehensively tested for DNP performance in lipid bilayers, some of them developed specifically for DNP investigations of membranes. The membrane-anchored biradicals PyPol-C16, AMUPOL-cholesterol, and bTurea-C16 were found to exhibit improved g-tensor alignment, inter-radical distance, and dispersion. Consequently, these biradicals show the highest signal enhancement factors so far obtained for matrix-free membranes or other matrix-free samples and may potentially shorten NMR acquisition times by three orders of magnitude. Furthermore, the optimal biradical-to-lipid ratio, sample deuteration, and membrane lipid composition were determined under static and MAS conditions. To rationalize biradical performance better, DNP enhancement was measured by using the 13 C and 15 N signals of lipids and a peptide as a function of the biradical concentration, DNP build-up time, resonance line width, quenching effect, microwave power, and MAS frequency.
Collapse
Affiliation(s)
- Evgeniy S Salnikov
- Institut de chimie, UMR 7177, Université de Strasbourg/CNRS, 4, rue Blaise Pascal, 67070, Strasbourg, France
| | - Sébastien Abel
- Aix Marseille Univ, CNRS, ICR UMR 7273, 13013, Marseille, France
| | | | - Hakim Karoui
- Aix Marseille Univ, CNRS, ICR UMR 7273, 13013, Marseille, France
| | - Fabien Aussenac
- Bruker Biospin, 34, rue de l'industrie, 67166, Wissembourg, France
| | - Paul Tordo
- Aix Marseille Univ, CNRS, ICR UMR 7273, 13013, Marseille, France
| | - Burkhard Bechinger
- Institut de chimie, UMR 7177, Université de Strasbourg/CNRS, 4, rue Blaise Pascal, 67070, Strasbourg, France
| | - Olivier Ouari
- Aix Marseille Univ, CNRS, ICR UMR 7273, 13013, Marseille, France
| |
Collapse
|
9
|
Frozen Acrylamide Gels as Dynamic Nuclear Polarization Matrices. Angew Chem Int Ed Engl 2017; 56:8726-8730. [DOI: 10.1002/anie.201703758] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Indexed: 01/08/2023]
|
10
|
Michurin OM, Afonin S, Berditsch M, Daniliuc CG, Ulrich AS, Komarov IV, Radchenko DS. Delivering Structural Information on the Polar Face of Membrane‐Active Peptides:
19
F‐NMR Labels with a Cationic Side Chain. Angew Chem Int Ed Engl 2016; 55:14595-14599. [DOI: 10.1002/anie.201607161] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 09/14/2016] [Indexed: 12/16/2022]
Affiliation(s)
| | - Sergii Afonin
- Institute of Biological Interfaces (IBG-2) Karlsruhe Institute of Technology (KIT) POB 3640 76021 Karlsruhe Germany
| | - Marina Berditsch
- Institute of Organic Chemistry (IOC) KIT Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Constantin G. Daniliuc
- Institute of Organic Chemistry Westfalische Wilhelms-Universität Münster Corrensstrasse 40 48149 Münster Germany
| | - Anne S. Ulrich
- Institute of Biological Interfaces (IBG-2) Karlsruhe Institute of Technology (KIT) POB 3640 76021 Karlsruhe Germany
- Institute of Organic Chemistry (IOC) KIT Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Igor V. Komarov
- Institute of High Technologies Taras Shevchenko National University of Kyiv vul. Volodymyrska 60 01601 Kyiv Ukraine
| | - Dmytro S. Radchenko
- Enamine Ltd. vul. Chervonotkatska 78 02094 Kyiv Ukraine
- Institute of Organic Chemistry (IOC) KIT Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| |
Collapse
|
11
|
Michurin OM, Afonin S, Berditsch M, Daniliuc CG, Ulrich AS, Komarov IV, Radchenko DS. Delivering Structural Information on the Polar Face of Membrane-Active Peptides: 19
F-NMR Labels with a Cationic Side Chain. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201607161] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | - Sergii Afonin
- Institute of Biological Interfaces (IBG-2); Karlsruhe Institute of Technology (KIT); POB 3640 76021 Karlsruhe Germany
| | - Marina Berditsch
- Institute of Organic Chemistry (IOC); KIT; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Constantin G. Daniliuc
- Institute of Organic Chemistry; Westfalische Wilhelms-Universität Münster; Corrensstrasse 40 48149 Münster Germany
| | - Anne S. Ulrich
- Institute of Biological Interfaces (IBG-2); Karlsruhe Institute of Technology (KIT); POB 3640 76021 Karlsruhe Germany
- Institute of Organic Chemistry (IOC); KIT; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Igor V. Komarov
- Institute of High Technologies; Taras Shevchenko National University of Kyiv; vul. Volodymyrska 60 01601 Kyiv Ukraine
| | - Dmytro S. Radchenko
- Enamine Ltd.; vul. Chervonotkatska 78 02094 Kyiv Ukraine
- Institute of Organic Chemistry (IOC); KIT; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| |
Collapse
|
12
|
Viennet T, Viegas A, Kuepper A, Arens S, Gelev V, Petrov O, Grossmann TN, Heise H, Etzkorn M. Selective Protein Hyperpolarization in Cell Lysates Using Targeted Dynamic Nuclear Polarization. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201603205] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Thibault Viennet
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Aldino Viegas
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Arne Kuepper
- Chemical Genomics Centre of the Max Planck Society; Otto-Hahn-Str. 15 44227 Dortmund Germany
| | - Sabine Arens
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Vladimir Gelev
- Faculty of Chemistry and Pharmacy; Sofia University; 1 James Bourchier Blvd. 1164 Sofia Bulgaria
| | - Ognyan Petrov
- Faculty of Chemistry and Pharmacy; Sofia University; 1 James Bourchier Blvd. 1164 Sofia Bulgaria
| | - Tom N. Grossmann
- Chemical Genomics Centre of the Max Planck Society; Otto-Hahn-Str. 15 44227 Dortmund Germany
- VU University Amsterdam; Department of Chemistry and Pharmaceutical Sciences; De Boelelaan 1083 1081 HV Amsterdam The Netherlands
| | - Henrike Heise
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Manuel Etzkorn
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| |
Collapse
|
13
|
Viennet T, Viegas A, Kuepper A, Arens S, Gelev V, Petrov O, Grossmann TN, Heise H, Etzkorn M. Selective Protein Hyperpolarization in Cell Lysates Using Targeted Dynamic Nuclear Polarization. Angew Chem Int Ed Engl 2016; 55:10746-50. [DOI: 10.1002/anie.201603205] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Thibault Viennet
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Aldino Viegas
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Arne Kuepper
- Chemical Genomics Centre of the Max Planck Society; Otto-Hahn-Str. 15 44227 Dortmund Germany
| | - Sabine Arens
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Vladimir Gelev
- Faculty of Chemistry and Pharmacy; Sofia University; 1 James Bourchier Blvd. 1164 Sofia Bulgaria
| | - Ognyan Petrov
- Faculty of Chemistry and Pharmacy; Sofia University; 1 James Bourchier Blvd. 1164 Sofia Bulgaria
| | - Tom N. Grossmann
- Chemical Genomics Centre of the Max Planck Society; Otto-Hahn-Str. 15 44227 Dortmund Germany
- VU University Amsterdam; Department of Chemistry and Pharmaceutical Sciences; De Boelelaan 1083 1081 HV Amsterdam The Netherlands
| | - Henrike Heise
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| | - Manuel Etzkorn
- Institute of Physical Biology; Heinrich Heine University; Universitätsstr. 1 40225 Düsseldorf Germany
- Institute of Complex Systems (ICS-6); Forschungszentrum Jülich; Wilhelm Jonen Strasse Jülich Germany
| |
Collapse
|
14
|
Sauvée C, Casano G, Abel S, Rockenbauer A, Akhmetzyanov D, Karoui H, Siri D, Aussenac F, Maas W, Weber RT, Prisner T, Rosay M, Tordo P, Ouari O. Tailoring of Polarizing Agents in the bTurea Series for Cross-Effect Dynamic Nuclear Polarization in Aqueous Media. Chemistry 2016; 22:5598-606. [PMID: 26992052 DOI: 10.1002/chem.201504693] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Indexed: 11/10/2022]
Abstract
A series of 18 nitroxide biradicals derived from bTurea has been prepared, and their enhancement factors ɛ ((1)H) in cross-effect dynamic nuclear polarization (CE DNP) NMR experiments at 9.4 and 14.1 T and 100 K in a DNP-optimized glycerol/water matrix ("DNP juice") have been studied. We observe that ɛ ((1)H) is strongly correlated with the substituents on the polarizing agents, and its trend is discussed in terms of different molecular parameters: solubility, average e-e distance, relative orientation of the nitroxide moieties, and electron spin relaxation times. We show that too short an e-e distance or too long a T1e can dramatically limit ɛ ((1)H). Our study also shows that the molecular structure of AMUPol is not optimal and its ɛ ((1)H) could be further improved through stronger interaction with the glassy matrix and a better orientation of the TEMPO moieties. A new AMUPol derivative introduced here provides a better ɛ ((1)H) than AMUPol itself (by a factor of ca. 1.2).
Collapse
Affiliation(s)
- Claire Sauvée
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France
| | - Gilles Casano
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France
| | - Sébastien Abel
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France
| | - Antal Rockenbauer
- Institute of Materials and Environmental Chemistry, Hungarian Academy of Sciences, Department of Physics, Budapest University of Technology and Economics and MTA-BME Condensed Matter Research Group, Budafoki ut 8, 1111, Budapest, Hungary
| | - Dimitry Akhmetzyanov
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue Str. 7, 60438, Frankfurt-am-Main, Germany
| | - Hakim Karoui
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France
| | - Didier Siri
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France
| | - Fabien Aussenac
- Bruker BioSpin S.A.S., 34 rue de l'industrie, 67166, Wissembourg, France
| | - Werner Maas
- Bruker BioSpin Corporation, 15 Fortune Drive, Billerica, Massachusetts, 01821, USA
| | - Ralph T Weber
- Bruker BioSpin Corporation, 15 Fortune Drive, Billerica, Massachusetts, 01821, USA
| | - Thomas Prisner
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue Str. 7, 60438, Frankfurt-am-Main, Germany
| | - Mélanie Rosay
- Bruker BioSpin Corporation, 15 Fortune Drive, Billerica, Massachusetts, 01821, USA
| | - Paul Tordo
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France.
| | - Olivier Ouari
- Aix-Marseille Université, CNRS, ICR UMR 7273, 13397, Marseille cedex 20, France.
| |
Collapse
|