1
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Cheney DJ, Cerreia Vioglio P, Brookfield A, Blanc F. Optimisation of dynamic nuclear polarisation using "off-the-shelf" Gd(III)-based polarising agents. Phys Chem Chem Phys 2024; 26:24395-24406. [PMID: 39258402 DOI: 10.1039/d4cp02924k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
Complexes of paramagnetic metal ions, in particular Gd3+, have been demonstrated as efficient polarising agents for magic-angle spinning (MAS) dynamic nuclear polarisation (DNP). We recently demonstrated that commercially available and inexpensive Gd(NO3)3 is suitable for use as an "off-the-shelf" MAS DNP polarising agent, providing promising sensitivity enhancements to 1H, 13C, and 15N NMR signals. Here we expand upon this approach by investigating the impact of the Gd(NO3)3 concentration and by exploring a larger range of readily available Gd3+ sources. We found that a Gd(NO3)3 concentration of 20 mM in the case of 1H and 13C, and 40 mM in the case of 15N, offers optimum signal enhancements and is rationalised as a trade-off between DNP enhancements, polarisation build-up times, and electron paramagnetic resonance (EPR) spin-spin relaxation times. We determined that a range of different gadolinium compounds (GdCl3, Gd2(SO4)3, GdBr3, and Gd(OAc)3) are also suitable for use as polarising agents and yield 1H, 13C, and 15N signal enhancements of variable values. Gd(OAc)3 yields lower signal enhancements, which is proposed to be the result of greater local asymmetry at the Gd3+ centre leading to EPR line broadening, and the methyl group in the acetate ion acting as a relaxation sink and limiting the nuclear polarisation available.
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Affiliation(s)
- Daniel J Cheney
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
| | - Paolo Cerreia Vioglio
- DNP MAS NMR Facility, Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham NG7 2RD, UK
| | - Adam Brookfield
- Department of Chemistry and Photon Science Institute, University of Manchester, Manchester M13 9PL, UK
| | - Frédéric Blanc
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
- Leverhulme Research Centre for Functional Materials Design, Materials Innovation Factory, University of Liverpool, Liverpool, L69 7ZD, UK
- Stephenson Institute for Renewable Energy, University of Liverpool, Liverpool L69 7ZF, UK
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2
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Moroz IB, Feldman Y, Carmieli R, Liu X, Leskes M. Endogenous metal-ion dynamic nuclear polarization for NMR signal enhancement in metal organic frameworks. Chem Sci 2023; 15:336-348. [PMID: 38131097 PMCID: PMC10731914 DOI: 10.1039/d3sc03456a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/23/2023] [Indexed: 12/23/2023] Open
Abstract
Rational design of metal-organic framework (MOF)-based materials for catalysis, gas capture and storage, requires deep understanding of the host-guest interactions between the MOF and the adsorbed molecules. Solid-State NMR spectroscopy is an established tool for obtaining such structural information, however its low sensitivity limits its application. This limitation can be overcome with dynamic nuclear polarization (DNP) which is based on polarization transfer from unpaired electrons to the nuclei of interest and, as a result, enhancement of the NMR signal. Typically, DNP is achieved by impregnating or wetting the MOF material with a solution of nitroxide biradicals, which prevents or interferes with the study of host-guest interactions. Here we demonstrate how Gd(iii) ions doped into the MOF structure, LaBTB (BTB = 4,4',4''-benzene-1,3,5-triyl-trisbenzoate), can be employed as an efficient polarization agent, yielding up to 30-fold 13C signal enhancement for the MOF linkers, while leaving the pores empty for potential guests. Furthermore, we demonstrate that ethylene glycol, loaded into the MOF as a guest, can also be polarized using our approach. We identify specific challenges in DNP studies of MOFs, associated with residual oxygen trapped within the MOF pores and the dynamics of the framework and its guests, even at cryogenic temperatures. To address these, we describe optimal conditions for carrying out and maximizing the enhancement achieved in DNP-NMR experiments. The approach presented here can be expanded to other porous materials which are currently the state-of-the-art in energy and sustainability research.
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Affiliation(s)
- Ilia B Moroz
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 76100 Israel
| | - Yishay Feldman
- Department of Chemical Research Support, Weizmann Institute of Science Rehovot 76100 Israel
| | - Raanan Carmieli
- Department of Chemical Research Support, Weizmann Institute of Science Rehovot 76100 Israel
| | - Xinyu Liu
- Yusuf Hamied Department of Chemistry, University of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Michal Leskes
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 76100 Israel
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3
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Hope MA, Zhang Y, Venkatesh A, Emsley L. Dynamic nuclear polarisation of 1H in Gd-doped In(OH) 3. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 353:107509. [PMID: 37331306 DOI: 10.1016/j.jmr.2023.107509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/08/2023] [Accepted: 06/09/2023] [Indexed: 06/20/2023]
Abstract
Dynamic nuclear polarisation (DNP) of solids doped with high-spin metal ions, such as Gd3+, is a useful strategy to enhance the nuclear magnetic resonance (NMR) sensitivity for these samples. Spin diffusion can relay polarisation throughout a sample, which is most effective for dense 1H networks, while the efficiency of DNP using Gd3+ depends on the symmetry of the metal site. Here, we investigate cubic In(OH)3 as a high-symmetry, proton-containing material for endogenous Gd DNP. A 1H enhancement of up to 9 is demonstrated and harnessed to measure the 17O spectrum at natural abundance. The enhancement is interpreted in terms of clustering of the Gd3+ dopants and the local reduction in symmetry of the metal site induced by proton disorder, as demonstrated by quadrupolar 115In NMR. This is the first example of 1H DNP using Gd3+ dopants in an inorganic solid.
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Affiliation(s)
- Michael A Hope
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - Yuxuan Zhang
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Amrit Venkatesh
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Lyndon Emsley
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
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4
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Mishra A, Hope MA, Stevanato G, Kubicki DJ, Emsley L. Dynamic Nuclear Polarization of Inorganic Halide Perovskites. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:11094-11102. [PMID: 37342202 PMCID: PMC10278140 DOI: 10.1021/acs.jpcc.3c01527] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/23/2023] [Indexed: 06/22/2023]
Abstract
The intrinsic low sensitivity of nuclear magnetic resonance (NMR) experiments limits their utility for structure determination of materials. Dynamic nuclear polarization (DNP) under magic angle spinning (MAS) has shown tremendous potential to overcome this key limitation, enabling the acquisition of highly selective and sensitive NMR spectra. However, so far, DNP methods have not been explored in the context of inorganic lead halide perovskites, which are a leading class of semiconductor materials for optoelectronic applications. In this work, we study cesium lead chloride and quantitatively compare DNP methods based on impregnation with a solution of organic biradicals with doping of high-spin metal ions (Mn2+) into the perovskite structure. We find that metal-ion DNP provides the highest bulk sensitivity in this case, while highly surface-selective NMR spectra can be acquired using impregnation DNP. The performance of both methods is explained in terms of the relaxation times, particle size, dopant concentration, and surface wettability. We envisage the future use of DNP NMR approaches in establishing structure-activity relationships in inorganic perovskites, especially for mass-limited samples such as thin films.
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5
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Menzildjian G, Schlagnitweit J, Casano G, Ouari O, Gajan D, Lesage A. Polarizing agents for efficient high field DNP solid-state NMR spectroscopy under magic-angle spinning: from design principles to formulation strategies. Chem Sci 2023; 14:6120-6148. [PMID: 37325158 PMCID: PMC10266460 DOI: 10.1039/d3sc01079a] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
Dynamic Nuclear Polarization (DNP) has recently emerged as a cornerstone approach to enhance the sensitivity of solid-state NMR spectroscopy under Magic Angle Spinning (MAS), opening unprecedented analytical opportunities in chemistry and biology. DNP relies on a polarization transfer from unpaired electrons (present in endogenous or exogenous polarizing agents) to nearby nuclei. Developing and designing new polarizing sources for DNP solid-state NMR spectroscopy is currently an extremely active research field per se, that has recently led to significant breakthroughs and key achievements, in particular at high magnetic fields. This review describes recent developments in this area, highlighting key design principles that have been established over time and led to the introduction of increasingly more efficient polarizing sources. After a short introduction, Section 2 presents a brief history of solid-state DNP, highlighting the main polarization transfer schemes. The third section is devoted to the development of dinitroxide radicals, discussing the guidelines that were progressively established to design the fine-tuned molecular structures in use today. In Section 4, we describe recent efforts in developing hybrid radicals composed of a narrow EPR line radical covalently linked to a nitroxide, highlighting the parameters that modulate the DNP efficiency of these mixed structures. Section 5 reviews recent advances in the design of metal complexes suitable for DNP MAS NMR as exogenous electron sources. In parallel, current strategies that exploit metal ions as endogenous polarization sources are discussed. Section 6 briefly describes the recent introduction of mixed-valence radicals. In the last part, experimental aspects regarding sample formulation are reviewed to make best use of these polarizing agents in a broad panel of application fields.
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Affiliation(s)
- Georges Menzildjian
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Judith Schlagnitweit
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Gilles Casano
- Aix Marseille Univ., CNRS, Institut de Chimie Radicalaire, UMR 7273 Marseille France
| | - Olivier Ouari
- Aix Marseille Univ., CNRS, Institut de Chimie Radicalaire, UMR 7273 Marseille France
| | - David Gajan
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Anne Lesage
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
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6
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Karmakar A, Bernard GM, Pominov A, Tabassum T, Chaklashiya R, Han S, Jain SK, Michaelis VK. Triangulating Dopant-Level Mn(II) Insertion in a Cs 2NaBiCl 6 Double Perovskite Using Magnetic Resonance Spectroscopy. J Am Chem Soc 2023; 145:4485-4499. [PMID: 36787417 DOI: 10.1021/jacs.2c10915] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Lead-free metal halide double perovskites are gaining increasing attention for optoelectronic applications. Specifically, doping metal halide double perovskites using transition metals enables broadband tailorability of the optical bandgap for these emerging semiconducting materials. One candidate material is Mn(II)-doped Cs2NaBiCl6, but the nature of Mn(II) insertion on chemical structure is poorly understood due to low Mn loading. It is critical to determine the atomic-level structure at the site of Mn(II) incorporation in doped perovskites to better understand the structure-property relationships in these materials and thus to advance their applicability to optoelectronic applications. Magnetic resonance spectroscopy is uniquely qualified to address this, and thus a comprehensive three-pronged strategy, involving solid-state nuclear magnetic resonance (NMR), high-field dynamic nuclear polarization (DNP), and electron paramagnetic resonance (EPR) spectroscopies, is used to identify the location of Mn(II) insertion in Cs2NaBiCl6. Multinuclear (23Na, 35Cl, 133Cs, and 209Bi) one-dimensional (1D) magnetic resonance spectra reveal a low level of Mn(II) incorporation, with select spins affected by paramagnetic relaxation enhancement (PRE) induced by Mn(II) neighbors. EPR measurements confirm the oxidation state, octahedral symmetry, and low doping levels of the Mn(II) centers. Complementary EPR and NMR measurements confirm that the cubic structure is maintained with Mn(II) incorporation at room temperature, but the structure deviates slightly from cubic symmetry at low temperatures (<30 K). HYperfine Sublevel CORrelation (HYSCORE) EPR spectroscopy explores the electron-nuclear correlations of Mn(II) with 23Na, 133Cs, and 35Cl. The absence of 209Bi correlations suggests that Bi centers are replaced by Mn(II). Endogenous DNP NMR measurements from Mn(II) → 133Cs (<30 K) reveal that the solid effect is the dominant mechanism for DNP transfer and supports that Mn(II) is homogeneously distributed within the double-perovskite structure.
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Affiliation(s)
- Abhoy Karmakar
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Guy M Bernard
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Arkadii Pominov
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Tarnuma Tabassum
- Department of Chemistry and Biochemistry, University of California─Santa Barbara, Santa Barbara, California 93106, United States
| | - Raj Chaklashiya
- Materials Department, University of California─Santa Barbara, Santa Barbara, California 93106, United States
| | - Songi Han
- Department of Chemistry and Biochemistry, University of California─Santa Barbara, Santa Barbara, California 93106, United States
| | - Sheetal K Jain
- Department of Chemistry and Biochemistry, University of California─Santa Barbara, Santa Barbara, California 93106, United States.,Solid-State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Vladimir K Michaelis
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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7
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Lunghi A. Toward exact predictions of spin-phonon relaxation times: An ab initio implementation of open quantum systems theory. SCIENCE ADVANCES 2022; 8:eabn7880. [PMID: 35930642 PMCID: PMC9355363 DOI: 10.1126/sciadv.abn7880] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 06/23/2022] [Indexed: 05/28/2023]
Abstract
Spin-phonon coupling is the main driver of spin relaxation and decoherence in solid-state semiconductors at finite temperature. Controlling this interaction is a central problem for many disciplines, ranging from magnetic resonance to quantum technologies. Spin relaxation theories have been developed for almost a century but often use a phenomenological description of phonons and their coupling to spin, resulting in a nonpredictive tool and hindering our detailed understanding of spin dynamics. Here, we combine time-local master equations up to the fourth order with advanced electronic structure methods and perform predictions of spin-phonon relaxation time for a series of solid-state coordination compounds based on both transition metals and lanthanide Kramers ions. The agreement between experiments and simulations demonstrates that an accurate, universal, and fully ab initio implementation of spin relaxation theory is possible, thus paving the way to a systematic study of spin-phonon relaxation in solid-state materials.
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Affiliation(s)
- Alessandro Lunghi
- School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2, Ireland
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8
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Carnahan SL, Chen Y, Wishart JF, Lubach JW, Rossini AJ. Magic angle spinning dynamic nuclear polarization solid-state NMR spectroscopy of γ-irradiated molecular organic solids. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2022; 119:101785. [PMID: 35405629 DOI: 10.1016/j.ssnmr.2022.101785] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 02/22/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
In the past 15 years, magic angle spinning (MAS) dynamic nuclear polarization (DNP) has emerged as a method to increase the sensitivity of high-resolution solid-state NMR spectroscopy experiments. Recently, γ-irradiation has been used to generate significant concentrations of homogeneously distributed free radicals in a variety of solids, including quartz, glucose, and cellulose. Both γ-irradiated quartz and glucose previously showed significant MAS DNP enhancements. Here, γ-irradiation is applied to twelve small organic molecules to test the applicability of γ-irradiation as a general method of creating stable free radicals for MAS DNP experiments on organic solids and pharmaceuticals. Radical concentrations in the range of 0.25 mM-10 mM were observed in irradiated glucose, histidine, malic acid, and malonic acid, and significant 1H DNP enhancements of 32, 130, 19, and 11 were obtained, respectively, as measured by 1H→13C CPMAS experiments. However, concentrations of free radicals below 0.05 mM were generally observed in organic molecules containing aromatic rings, preventing sizeable DNP enhancements. DNP sensitivity gains for several of the irradiated compounds exceed that which can be obtained with the relayed DNP approach that uses exogeneous polarizing agent solutions and impregnation procedures. In several cases, significant 1H DNP enhancements were realized at room temperature. This study demonstrates that in many cases γ-irradiation is a viable alternative to addition of stable exogenous radicals for DNP experiments on organic solids.
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Affiliation(s)
- Scott L Carnahan
- US DOE Ames Laboratory, Ames, IA, 50011, USA; Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - Yunhua Chen
- US DOE Ames Laboratory, Ames, IA, 50011, USA; Iowa State University, Department of Chemistry, Ames, IA, 50011, USA
| | - James F Wishart
- Brookhaven National Laboratory, Chemistry Division, Upton, NY, 11973, United States
| | - Joseph W Lubach
- Genentech Inc., South San Francisco, CA, 94080, United States
| | - Aaron J Rossini
- US DOE Ames Laboratory, Ames, IA, 50011, USA; Iowa State University, Department of Chemistry, Ames, IA, 50011, USA.
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9
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Üngör Ö, Ozvat TM, Ni Z, Zadrozny JM. Record Chemical-Shift Temperature Sensitivity in a Series of Trinuclear Cobalt Complexes. J Am Chem Soc 2022; 144:9132-9137. [PMID: 35549174 DOI: 10.1021/jacs.2c03115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Designing spins that exhibit long-lived coherence and strong temperature sensitivity is central to designing effective molecular thermometers and a fundamental challenge in the chemistry/quantum-information space. Herein, we provide a new pathway to both properties in the same molecule by designing a nuclear spin, which possesses a robust spin coherence, to mimic the strong temperature sensitivity of an electronic spin. This design strategy is demonstrated in the group of trinuclear Co(III) spin-crossover compounds [(CpCo(OP(OR)2)3)2Co](SbCl6) where Cp = cyclopentadienyl and R = Me (1), Et (2), i-Pr (3), and t-Bu (4). Nuclear magnetic resonance analyses of the 59Co nuclear spins reveal 59Co chemical-shift temperature sensitivity (Δδ/ΔT) values that span from 101(1) ppm/°C in 1 to 149(1) ppm/°C in 2 and 150(2) ppm/°C in 4, where the latter two are record temperature sensitivities for any nuclear spin. Additionally, complexes 2 and 4 have T2* values of 74 and 78 μs in solution at ambient temperatures surpassing those from electron-spin-based complexes, which typically display long coherence times only at extremely low temperatures. Our results suggest that spin-crossover phenomena can enable electron-spin-like temperature sensitivities in nuclear spins while retaining robust coherence times at room temperature.
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Affiliation(s)
- Ökten Üngör
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Tyler M Ozvat
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Zhen Ni
- Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States
| | - Joseph M Zadrozny
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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10
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Jardón-Álvarez D, Malka T, van Tol J, Feldman Y, Carmieli R, Leskes M. Monitoring electron spin fluctuations with paramagnetic relaxation enhancement. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 336:107143. [PMID: 35085928 DOI: 10.1016/j.jmr.2022.107143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 06/14/2023]
Abstract
The magnetic interactions between the spin of an unpaired electron and the surrounding nuclear spins can be exploited to gain structural information, to reduce nuclear relaxation times as well as to create nuclear hyperpolarization via dynamic nuclear polarization (DNP). A central aspect that determines how these interactions manifest from the point of view of NMR is the timescale of the fluctuations of the magnetic moment of the electron spins. These fluctuations, however, are elusive, particularly when electron relaxation times are short or interactions among electronic spins are strong. Here we map the fluctuations by analyzing the ratio between longitudinal and transverse nuclear relaxation times T1/T2, a quantity which depends uniquely on the rate of the electron fluctuations and the Larmor frequency of the involved nuclei. This analysis enables rationalizing the evolution of NMR lineshapes, signal quenching as well as DNP enhancements as a function of the concentration of the paramagnetic species and the temperature, demonstrated here for LiMg1-xMnxPO4 and Fe(III) doped Li4Ti5O12, respectively. For the latter, we observe a linear dependence of the DNP enhancement and the electron relaxation time within a temperature range between 100 and 300 K.
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Affiliation(s)
- Daniel Jardón-Álvarez
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tahel Malka
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Johan van Tol
- National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Dr, Tallahassee, FL 32310, United States
| | - Yishay Feldman
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Raanan Carmieli
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Michal Leskes
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 76100, Israel.
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11
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Haber S, Leskes M. Dynamic Nuclear Polarization in battery materials. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2022; 117:101763. [PMID: 34890977 DOI: 10.1016/j.ssnmr.2021.101763] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/21/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
The increasing need for portable and large-scale energy storage systems requires development of new, long lasting and highly efficient battery systems. Solid state NMR spectroscopy has emerged as an excellent method for characterizing battery materials. Yet, it is limited when it comes to probing thin interfacial layers which play a central role in the performance and lifetime of battery cells. Here we review how Dynamic Nuclear Polarization (DNP) can lift the sensitivity limitation and enable detection of the electrode-electrolyte interface, as well as the bulk of some electrode and electrolyte systems. We describe the current challenges from the point of view of materials development; considering how the unique electronic, magnetic and chemical properties differentiate battery materials from other applications of DNP in materials science. We review the current applications of exogenous and endogenous DNP from radicals, conduction electrons and paramagnetic metal ions. Finally, we provide our perspective on the opportunities and directions where battery materials can benefit from current DNP methodologies as well as project on future developments that will enable NMR investigation of battery materials with sensitivity and selectivity under ambient conditions.
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Affiliation(s)
- Shira Haber
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Michal Leskes
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel.
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12
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Biedenbänder T, Aladin V, Saeidpour S, Corzilius B. Dynamic Nuclear Polarization for Sensitivity Enhancement in Biomolecular Solid-State NMR. Chem Rev 2022; 122:9738-9794. [PMID: 35099939 DOI: 10.1021/acs.chemrev.1c00776] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Solid-state NMR with magic-angle spinning (MAS) is an important method in structural biology. While NMR can provide invaluable information about local geometry on an atomic scale even for large biomolecular assemblies lacking long-range order, it is often limited by low sensitivity due to small nuclear spin polarization in thermal equilibrium. Dynamic nuclear polarization (DNP) has evolved during the last decades to become a powerful method capable of increasing this sensitivity by two to three orders of magnitude, thereby reducing the valuable experimental time from weeks or months to just hours or days; in many cases, this allows experiments that would be otherwise completely unfeasible. In this review, we give an overview of the developments that have opened the field for DNP-enhanced biomolecular solid-state NMR including state-of-the-art applications at fast MAS and high magnetic field. We present DNP mechanisms, polarizing agents, and sample constitution methods suitable for biomolecules. A wide field of biomolecular NMR applications is covered including membrane proteins, amyloid fibrils, large biomolecular assemblies, and biomaterials. Finally, we present perspectives and recent developments that may shape the field of biomolecular DNP in the future.
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Affiliation(s)
- Thomas Biedenbänder
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Victoria Aladin
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Siavash Saeidpour
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Björn Corzilius
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
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13
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Mentink-Vigier F. Numerical recipes for faster MAS-DNP simulations. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 333:107106. [PMID: 34837803 PMCID: PMC8639796 DOI: 10.1016/j.jmr.2021.107106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/05/2021] [Accepted: 11/07/2021] [Indexed: 05/11/2023]
Abstract
Numerical simulations of Magic Angle Spinning Dynamic Nuclear Polarization (MAS-DNP) have transformed the way the DNP process is understood in rotating samples. In 2012, two methods were concomitantly developed to simulate small spin systems (< 4 spin-1/2). The development of new polarizing agents, including those containing metal centers with S > 1/2, makes it necessary to further expand the numerical tools with minimal approximations that will help rationalize the experimental observations and build approximate models. In this paper, three strategies developed in the past five years are presented: an adaptive integration scheme, a hybrid Hilbert/Liouville formalism, and a method to truncate the Liouville space basis for periodic Hamiltonian. Each of these methods enable time savings ranging from a factor of 3 to > 100. We illustrate the code performance by reporting for the first time the MAS-DNP field profiles for "AMUPol", in which the couplings to the nitrogen nuclei are explicitly considered, as well as Cross-Effect MAS-DNP field profiles with two electrons spin 5/2 interacting with a nuclear spin 1/2.
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Affiliation(s)
- Frederic Mentink-Vigier
- National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Dr, FL 32310, USA.
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14
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Haber S, Rosy, Saha A, Brontvein O, Carmieli R, Zohar A, Noked M, Leskes M. Structure and Functionality of an Alkylated Li xSi yO z Interphase for High-Energy Cathodes from DNP-ssNMR Spectroscopy. J Am Chem Soc 2021; 143:4694-4704. [PMID: 33751895 PMCID: PMC8017524 DOI: 10.1021/jacs.1c00215] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Degradation processes
at the cathode–electrolyte interface
are a major limitation in the development of high-energy lithium-ion
rechargeable batteries. Deposition of protective thin coating layers
on the surface of high-energy cathodes is a promising approach to
control interfacial reactions. However, rational design of effective
protection layers is limited by the scarcity of analytical tools that
can probe thin, disordered, and heterogeneous phases. Here we propose
a new structural approach based on solid-state nuclear magnetic resonance
spectroscopy coupled with dynamic nuclear polarization (DNP) for characterizing
thin coating layers. We demonstrate the approach on an efficient alkylated
LixSiyOz coating layer. By utilizing different sources
for DNP, exogenous from nitroxide biradicals and endogenous from paramagnetic
metal ion dopants, we reveal the outer and inner surface layers of
the deposited artificial interphase and construct a structural model
for the coating. In addition, lithium isotope exchange experiments
provide direct evidence for the function of the surface layer, shedding
light on its role in the enhanced rate performance of coated cathodes.
The presented methodology and results advance us in identifying the
key properties of effective coatings and may enable rational design
of protective and ion-conducting surface layers.
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Affiliation(s)
- Shira Haber
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel 7610001
| | - Rosy
- Department of Chemistry, Indian Institute of Technology BHU, Varanasi, India 221005
| | - Arka Saha
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel.,Bar-Ilan Institute of Nanotechnology and Advanced Materials, Ramat Gan, Israel
| | - Olga Brontvein
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel 7610001
| | - Raanan Carmieli
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel 7610001
| | - Arava Zohar
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel 7610001
| | - Malachi Noked
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel.,Bar-Ilan Institute of Nanotechnology and Advanced Materials, Ramat Gan, Israel
| | - Michal Leskes
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel 7610001
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15
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Jain SK, Yu CJ, Wilson CB, Tabassum T, Freedman DE, Han S. Dynamic Nuclear Polarization with Vanadium(IV) Metal Centers. Chem 2021. [DOI: 10.1016/j.chempr.2020.10.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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16
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Heiliger J, Matzel T, Çetiner EC, Schwalbe H, Kuenze G, Corzilius B. Site-specific dynamic nuclear polarization in a Gd(III)-labeled protein. Phys Chem Chem Phys 2020; 22:25455-25466. [PMID: 33103678 DOI: 10.1039/d0cp05021k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Dynamic nuclear polarization (DNP) of a biomolecule tagged with a polarizing agent has the potential to not only increase NMR sensitivity but also to provide specificity towards the tagging site. Although the general concept has been often discussed, the observation of true site-specific DNP and its dependence on the electron-nuclear distance has been elusive. Here, we demonstrate site-specific DNP in a uniformly isotope-labeled ubiquitin. By recombinant expression of three different ubiquitin point mutants (F4C, A28C, and G75C) post-translationally modified with a Gd3+-chelator tag, localized metal-ion DNP of 13C and 15N is investigated. Effects counteracting the site-specificity of DNP such as nuclear spin-lattice relaxation and proton-driven spin diffusion have been attenuated by perdeuteration of the protein. Particularly for 15N, large DNP enhancement factors on the order of 100 and above as well as localized effects within side-chain resonances differently distributed over the protein are observed. By analyzing the experimental DNP built-up dynamics combined with structural modeling of Gd3+-tags in ubiquitin supported by paramagnetic relaxation enhancement (PRE) in solution, we provide, for the first time, quantitative information on the distance dependence of the initial DNP transfer. We show that the direct 15N DNP transfer rate indeed linearly depends on the square of the hyperfine interaction between the electron and the nucleus following Fermi's golden rule, however, below a certain distance cutoff paramagnetic signal bleaching may dramatically skew the correlation.
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Affiliation(s)
- Jörg Heiliger
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany
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17
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Harchol A, Reuveni G, Ri V, Thomas B, Carmieli R, Herber RH, Kim C, Leskes M. Endogenous Dynamic Nuclear Polarization for Sensitivity Enhancement in Solid-State NMR of Electrode Materials. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:7082-7090. [PMID: 32273937 PMCID: PMC7133110 DOI: 10.1021/acs.jpcc.0c00858] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Indexed: 05/25/2023]
Abstract
Rational design of materials for energy storage systems relies on our ability to probe these materials at various length scales. Solid-state NMR spectroscopy is a powerful approach for gaining chemical and structural insights at the atomic/molecular level, but its low detection sensitivity often limits applicability. This limitation can be overcome by transferring the high polarization of electron spins to the sample of interest in a process called dynamic nuclear polarization (DNP). Here, we employ for the first time metal ion-based DNP to probe pristine and cycled composite battery electrodes. A new and efficient DNP agent, Fe(III), is introduced, yielding lithium signal enhancement up to 180 when substituted in the anode material Li4Ti5O12. In addition for being DNP active, Fe(III) improves the anode performance. Reduction of Fe(III) to Fe(II) upon cycling can be monitored in the loss of DNP activity. We show that the dopant can be reactivated (return to Fe(III)) for DNP by increasing the cycling potential window. Furthermore, we demonstrate that the deleterious effect of carbon additives on the DNP process can be eliminated by using carbon free electrodes, doped with Fe(III) and Mn(II), which provide good electrochemical performance as well as sensitivity in DNP-NMR. We expect that the approach presented here will expand the applicability of DNP for studying materials for frontier challenges in materials chemistry associated with energy and sustainability.
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Affiliation(s)
- Adi Harchol
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Guy Reuveni
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Vitalii Ri
- Department
of Materials Science and Engineering, Chungham
National University, Daejeon 305-764, Republic of Korea
| | - Brijith Thomas
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Raanan Carmieli
- Department
of Chemical Research Support, Weizmann Institute
of Science, Rehovot 76100, Israel
| | - Rolfe H. Herber
- Racah
Institute of Physics, The Hebrew University
of Jerusalem, Jerusalem 91905, Israel
| | - Chunjoong Kim
- Department
of Materials Science and Engineering, Chungham
National University, Daejeon 305-764, Republic of Korea
| | - Michal Leskes
- Department
of Materials and Interfaces, Weizmann Institute
of Science, Rehovot 76100, Israel
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18
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Abstract
Dynamic nuclear polarization (DNP) is one of the most prominent methods of sensitivity enhancement in nuclear magnetic resonance (NMR). Even though solid-state DNP under magic-angle spinning (MAS) has left the proof-of-concept phase and has become an important tool for structural investigations of biomolecules as well as materials, it is still far from mainstream applicability because of the potentially overwhelming combination of unique instrumentation, complex sample preparation, and a multitude of different mechanisms and methods available. In this review, I introduce the diverse field and history of DNP, combining aspects of NMR and electron paramagnetic resonance. I then explain the general concepts and detailed mechanisms relevant at high magnetic field, including solution-state methods based on Overhauser DNP but with a greater focus on the more established MAS DNP methods. Finally, I review practical considerations and fields of application and discuss future developments.
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Affiliation(s)
- Björn Corzilius
- Institute of Chemistry and Department of Life, Light and Matter, University of Rostock, 18059 Rostock, Germany;
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19
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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.
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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
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20
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Manjunatha Reddy GN, Gerbec JA, Shimizu F, Chmelka BF. Nanoscale Surface Compositions and Structures Influence Boron Adsorption Properties of Anion Exchange Resins. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15661-15673. [PMID: 31479272 DOI: 10.1021/acs.langmuir.9b02042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Boron adsorption properties of poly(styrene-co-divinylbenzene) (PSDVB)-based anion-exchange resins with surface-grafted N-methyl-d-glucamine (NMDG) depend strongly on their local surface compositions, structures, and interfacial interactions. Distinct boron adsorption sites have been identified and quantified, and interactions between borate anions and hydroxyl groups of NMDG surface moieties have been established. A combination of X-ray photoelectron spectroscopy (XPS), solid-state nuclear magnetic resonance (NMR), and Fourier-transform infrared (FT-IR) spectroscopy were used to characterize the atomic-level compositions and structures that directly influence the adsorption of borate anions on the NMDG-functionalized resin surface. Surface-enhanced dynamic-nuclear-polarization (DNP)-NMR enabled dilute (3 atom % N) tertiary alkyl amines and quaternary ammonium ions of the NMDG groups to be detected and distinguished with unprecedented sensitivity and resolution at natural abundance 15N (0.4%). Two-dimensional (2D) solid-state 11B{1H}, 13C{1H}, and 11B{11B} NMR analyses provide direct atomic-scale evidence for interactions of borate anions with the NMDG moieties on the resin surfaces, which form stable mono- and bischelate complexes. FT-IR spectra reveal displacements in the stretching vibrational frequencies associated with the O-H and N-H bonds of NMDG groups that corroborate the formation of chelate complexes on the resin surfaces. The atomic-level compositions and structures are related to boron adsorption properties of resin materials synthesized under different conditions, which have important remediation applications.
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Affiliation(s)
- G N Manjunatha Reddy
- Department of Chemical Engineering , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Jeffrey A Gerbec
- Mitsubishi Chemical-Center for Advanced Materials , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
| | - Fumihiko Shimizu
- Science and Innovation Center, Mitsubishi Chemical Corporation , Yokohama-shi , Kanagawa 227-8502 , Japan
| | - Bradley F Chmelka
- Department of Chemical Engineering , University of California, Santa Barbara , Santa Barbara , California 93106 , United States
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21
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Kocman V, Di Mauro GM, Veglia G, Ramamoorthy A. Use of paramagnetic systems to speed-up NMR data acquisition and for structural and dynamic studies. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 102:36-46. [PMID: 31325686 PMCID: PMC6698407 DOI: 10.1016/j.ssnmr.2019.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 05/05/2023]
Abstract
NMR spectroscopy is a powerful experimental technique to study biological systems at the atomic resolution. However, its intrinsic low sensitivity results in long acquisition times that in extreme cases lasts for days (or even weeks) often exceeding the lifetime of the sample under investigation. Different paramagnetic agents have been used in an effort to decrease the spin-lattice (T1) relaxation times of the studied nuclei, which are the main cause for long acquisition times necessary for signal averaging to enhance the signal-to-noise ratio of NMR spectra. Consequently, most of the experimental time is "wasted" in waiting for the magnetization to recover between successive scans. In this review, we discuss how to set up an optimal paramagnetic relaxation enhancement (PRE) system to effectively reduce the T1 relaxation times avoiding significant broadening of NMR signals. Additionally, we describe how PRE-agents can be used to provide structural and dynamic information and can even be used to follow the intermediates of chemical reactions and to speed-up data acquisition. We also describe the unique challenges and benefits associated with the application of PRE to solid-state NMR spectroscopy, explaining how the use of PREs is more complex for membrane mimetic systems as PREs can also be exploited to change the alignment of oriented membrane systems. Functionalization of membrane mimetics, such as bicelles, can provide a controlled region of paramagnetic effect that has the potential, together with the desired alignment, to provide crucial biologically relevant structural information. And finally, we discuss how paramagnetic metals can be utilized to further increase the dynamic nuclear polarization (DNP) effects and how to preserve the enhancements when dissolution DNP is implemented.
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Affiliation(s)
- Vojč Kocman
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA; Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI, USA
| | | | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA; Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI, USA.
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22
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Carnahan SL, Venkatesh A, Perras FA, Wishart JF, Rossini AJ. High-Field Magic Angle Spinning Dynamic Nuclear Polarization Using Radicals Created by γ-Irradiation. J Phys Chem Lett 2019; 10:4770-4776. [PMID: 31347850 DOI: 10.1021/acs.jpclett.9b01655] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
High-field magic angle spinning dynamic nuclear polarization (MAS DNP) is often used to enhance the sensitivity of solid-state nuclear magnetic resonance experiments by transferring spin polarization from electron spins to nuclear spins. Here, we demonstrate that γ-irradiation induces the formation of stable radicals in inorganic solids, such as fused quartz and borosilicate glasses, as well as organic solids, such as glucose, cellulose, and a urea/polyethylene polymer. The radicals were then used to polarize 29Si or 1H spins in the core of some of these materials. Significant MAS DNP enhancements (ε) of more than 400 and 30 were obtained for fused quartz and glucose, respectively. For other samples, negligible values of ε were obtained, likely due to low concentrations of radicals or the presence of abundant quadrupolar spins. These results demonstrate that ionizing radiation is a promising alternative method for generating stable radicals that are suitable for high-field MAS DNP experiments.
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Affiliation(s)
- Scott L Carnahan
- U.S. Department of Energy Ames Laboratory, Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Amrit Venkatesh
- U.S. Department of Energy Ames Laboratory, Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Frédéric A Perras
- U.S. Department of Energy Ames Laboratory, Ames, Iowa 50011, United States
| | - James F Wishart
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Aaron J Rossini
- U.S. Department of Energy Ames Laboratory, Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
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23
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Rankin AGM, Trébosc J, Pourpoint F, Amoureux JP, Lafon O. Recent developments in MAS DNP-NMR of materials. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 101:116-143. [PMID: 31189121 DOI: 10.1016/j.ssnmr.2019.05.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/21/2019] [Accepted: 05/21/2019] [Indexed: 05/03/2023]
Abstract
Solid-state NMR spectroscopy is a powerful technique for the characterization of the atomic-level structure and dynamics of materials. Nevertheless, the use of this technique is often limited by its lack of sensitivity, which can prevent the observation of surfaces, defects or insensitive isotopes. Dynamic Nuclear Polarization (DNP) has been shown to improve by one to three orders of magnitude the sensitivity of NMR experiments on materials under Magic-Angle Spinning (MAS), at static magnetic field B0 ≥ 5 T, conditions allowing for the acquisition of high-resolution spectra. The field of DNP-NMR spectroscopy of materials has undergone a rapid development in the last ten years, spurred notably by the availability of commercial DNP-NMR systems. We provide here an in-depth overview of MAS DNP-NMR studies of materials at high B0 field. After a historical perspective of DNP of materials, we describe the DNP transfers under MAS, the transport of polarization by spin diffusion and the various contributions to the overall sensitivity of DNP-NMR experiments. We discuss the design of tailored polarizing agents and the sample preparation in the case of materials. We present the DNP-NMR hardware and the influence of key experimental parameters, such as microwave power, magnetic field, temperature and MAS frequency. We give an overview of the isotopes that have been detected by this technique, and the NMR methods that have been combined with DNP. Finally, we show how MAS DNP-NMR has been applied to gain new insights into the structure of organic, hybrid and inorganic materials with applications in fields, such as health, energy, catalysis, optoelectronics etc.
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Affiliation(s)
- Andrew G M Rankin
- Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181, UCCS, Unité de Catalyse et Chimie du Solide, F-59000, Lille, France
| | - Julien Trébosc
- Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181, UCCS, Unité de Catalyse et Chimie du Solide, F-59000, Lille, France; Univ. Lille, CNRS-FR2638, Fédération Chevreul, F-59000 Lille, France
| | - Frédérique Pourpoint
- Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181, UCCS, Unité de Catalyse et Chimie du Solide, F-59000, Lille, France
| | - Jean-Paul Amoureux
- Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181, UCCS, Unité de Catalyse et Chimie du Solide, F-59000, Lille, France; Bruker Biospin, 34 rue de l'industrie, F-67166, Wissembourg, France
| | - Olivier Lafon
- Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181, UCCS, Unité de Catalyse et Chimie du Solide, F-59000, Lille, France; Institut Universitaire de France, 1 rue Descartes, F-75231, Paris, France.
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24
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Shimon D, van Schooten KJ, Paul S, Peng Z, Takahashi S, Köckenberger W, Ramanathan C. DNP-NMR of surface hydrogen on silicon microparticles. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 101:68-75. [PMID: 31128358 DOI: 10.1016/j.ssnmr.2019.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Dynamic nuclear polarization (DNP) enhanced nuclear magnetic resonance (NMR) offers a promising route to studying local atomic environments at the surface of both crystalline and amorphous materials. We take advantage of unpaired electrons due to defects close to the surface of the silicon microparticles to hyperpolarize adjacent 1H nuclei. At 3.3 T and 4.2 K, we observe the presence of two proton peaks, each with a linewidth on the order of 5 kHz. Echo experiments indicate a homogeneous linewidth of ∼150-300 Hz for both peaks, indicative of a sparse distribution of protons in both environments. The high frequency peak at 10 ppm lies within the typical chemical shift range for proton NMR, and was found to be relatively stable over repeated measurements. The low frequency peak was found to vary in position between -19 and -37 ppm, well outside the range of typical proton NMR shifts, and indicative of a high-degree of chemical shielding. The low frequency peak was also found to vary significantly in intensity across different experimental runs, suggesting a weakly-bound species. These results suggest that the hydrogen is located in two distinct microscopic environments on the surface of these Si particles.
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Affiliation(s)
- Daphna Shimon
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH, 03755, USA.
| | - Kipp J van Schooten
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH, 03755, USA
| | - Subhradip Paul
- School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Zaili Peng
- Department of Chemistry, University of Southern California, Los Angeles, CA, 90089, USA
| | - Susumu Takahashi
- Department of Chemistry, University of Southern California, Los Angeles, CA, 90089, USA; Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, 90089, USA
| | - Walter Köckenberger
- School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, UK
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25
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Ha M, Thiessen AN, Sergeyev IV, Veinot JGC, Michaelis VK. Endogenous dynamic nuclear polarization NMR of hydride-terminated silicon nanoparticles. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 100:77-84. [PMID: 31015058 DOI: 10.1016/j.ssnmr.2019.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 04/09/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
Silicon nanoparticles (SiNPs) are intriguing materials and their properties fascinate the broader scientific community; they are also attractive to the biological and materials science sub-disciplines because of their established biological and environmental compatibility, as well as their far-reaching practical applications. While characterization of the particle nanostructure can be performed using 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy, poor sensitivity due to low Boltzmann population and long acquisition times hinder in-depth studies of these potentially game-changing materials. In this study, we compare two dynamic nuclear polarization (DNP) NMR protocols to boost 29Si sensitivity in hydride-terminated SiNPs. First, we assess a traditional indirect DNP approach, where a nitroxide biradical (AMUPol or bCTbk) is incorporated into a glassing agent and transferred through protons (e- → 1H → 29Si) to enhance the silicon. In this mode, electron paramagnetic resonance (EPR) spectroscopy demonstrated that the hydride-terminated surface was highly reactive with the exogenous biradicals, thus decomposing the radicals within hours and resulting in an enhancement factor, ε, of 3 (TB = 15 s) for the 64 nm SiNP, revealing the surface components. Secondly, direct DNP NMR methods were used to enhance the silicon without the addition of an exogenous radical (i.e., use of dangling bonds as an endogenous radical source). With radical concentrations <1 mM, 29Si enhancements were obtained for the series of SiNPs ranging from 3 to 64 nm. The ability to use direct 29Si DNP transfer (e- → 29Si) shows promise for DNP studies of these inorganic nanomaterials (ε = 6 (TB = 79 min) for 64 nm SiNPs) with highly reactive surfaces, showing the sub-surface and core features. These preliminary findings lay a foundation for future endogenous radical development through tailoring the surface chemistry, targeting further sensitivity gains.
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Affiliation(s)
- Michelle Ha
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | | | - Ivan V Sergeyev
- Bruker-Biospin Corporation, 15 Fortune Drive, Billerica, MA, 01821, USA
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.
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26
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Ozvat TM, Peña ME, Zadrozny JM. Influence of ligand encapsulation on cobalt-59 chemical-shift thermometry. Chem Sci 2019; 10:6727-6734. [PMID: 31367328 PMCID: PMC6625495 DOI: 10.1039/c9sc01689a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 06/04/2019] [Indexed: 11/21/2022] Open
Abstract
This manuscript details the first investigation of ligand encapsulation on thermometry by cobalt-59 nuclear spins.
Thermometry via magnetic resonance imaging (MRI) would provide a powerful noninvasive window into physiological temperature management. Cobalt-59 nuclear spins demonstrate exceptional temperature dependence of their NMR chemical shifts, yet the insight to control this dependence via molecular design is lacking. We present the first systematic evidence that encapsulation of this spin system amplifies the temperature sensitivity. We tested the temperature dependence of the 59Co chemical shift (Δδ/ΔT) in a series of five low-spin cobalt(iii) complexes as a function of increasing encapsulation within the 1st coordination sphere. This study spans from [Co(NH3)6]Cl3, with no interligand connectivity, to a fully encapsulated dinitrosarcophagine (diNOsar) complex, [Co(diNOsar)]Cl3. We discovered Δδ/ΔT values that span from 1.44(2) ppm °C–1 in [Co(NH3)6]Cl3 to 2.04(2) ppm °C–1 in [Co(diNOsar)]Cl3, the latter among the highest for a molecular complex. The data herein suggest that designing 59Co NMR thermometers toward high chemical stability can be coincident with high Δδ/ΔT. To better understand this phenomenon, variable-temperature UV-Vis, 59Co NMR relaxation, Raman spectroscopic, and variable-solvent investigations were performed. Data from these measurements highlight an unexpected impact of encapsulation – an increasingly dynamic and flexible inner coordination sphere. These results comprise the first systematic studies to reveal insight into the molecular factors that govern Δδ/ΔT and provide the first evidence of 59Co nuclear-spin control via vibrational means.
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Affiliation(s)
- Tyler M Ozvat
- Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , USA .
| | - Manuel E Peña
- Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , USA .
| | - Joseph M Zadrozny
- Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , USA .
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27
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Wolf T, Kumar S, Singh H, Chakrabarty T, Aussenac F, Frenkel AI, Major DT, Leskes M. Endogenous Dynamic Nuclear Polarization for Natural Abundance 17O and Lithium NMR in the Bulk of Inorganic Solids. J Am Chem Soc 2018; 141:451-462. [DOI: 10.1021/jacs.8b11015] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tamar Wolf
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sandeep Kumar
- Department of Chemistry, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Harishchandra Singh
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794, United States
| | - Tanmoy Chakrabarty
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Fabien Aussenac
- Bruker BioSpin, 34 rue de l’Industrie BP 10002, 67166 Wissembourg Cedex, France
| | - Anatoly I. Frenkel
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794, United States
- Division of Chemistry, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Dan Thomas Major
- Department of Chemistry, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Michal Leskes
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel
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28
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Leroy C, Bryce DL. Recent advances in solid-state nuclear magnetic resonance spectroscopy of exotic nuclei. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:160-199. [PMID: 30527135 DOI: 10.1016/j.pnmrs.2018.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 07/18/2018] [Accepted: 08/10/2018] [Indexed: 06/09/2023]
Abstract
We present a review of recent advances in solid-state nuclear magnetic resonance (SSNMR) studies of exotic nuclei. Exotic nuclei may be spin-1/2 or quadrupolar, and typically have low gyromagnetic ratios, low natural abundances, large quadrupole moments (when I > 1/2), or some combination of these properties, generally resulting in low receptivities and/or prohibitively broad line widths. Some nuclides are little studied for other reasons, also rendering them somewhat exotic. We first discuss some of the recent progress in pulse sequences and hardware development which continues to enable researchers to study new kinds of materials as well as previously unfeasible nuclei. This is followed by a survey of applications to a wide range of exotic nuclei (including e.g., 9Be, 25Mg, 33S, 39K, 43Ca, 47/49Ti, 53Cr, 59Co, 61Ni, 67Zn, 73Ge, 75As, 87Sr, 115In, 119Sn, 121/123Sb, 135/137Ba, 185/187Re, 209Bi), most of them quadrupolar. The scope of the review is the past ten years, i.e., 2007-2017.
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Affiliation(s)
- César Leroy
- Department of Chemistry and Biomolecular Sciences & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario K1N 6N5, Canada
| | - David L Bryce
- Department of Chemistry and Biomolecular Sciences & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario K1N 6N5, Canada.
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29
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Chakrabarty T, Goldin N, Feintuch A, Houben L, Leskes M. Paramagnetic Metal-Ion Dopants as Polarization Agents for Dynamic Nuclear Polarization NMR Spectroscopy in Inorganic Solids. Chemphyschem 2018; 19:2139-2142. [DOI: 10.1002/cphc.201800462] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Indexed: 11/05/2022]
Affiliation(s)
- Tanmoy Chakrabarty
- Department of Materials and Interfaces; Weizmann Institute of Science; Rehovot 761000 Israel
| | - Nir Goldin
- Department of Materials and Interfaces; Weizmann Institute of Science; Rehovot 761000 Israel
| | - Akiva Feintuch
- Department of Biological and Chemical Physics; Weizmann Institute of Science; Rehovot 761000 Israel
| | - Lothar Houben
- Department of Chemical Research Support; Weizmann Institute of Science; Rehovot 761000 Israel
| | - Michal Leskes
- Department of Materials and Interfaces; Weizmann Institute of Science; Rehovot 761000 Israel
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30
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Burgess KMN, Widdifield CM, Xu Y, Leroy C, Bryce DL. Structural Insights from 59 Co Solid-State NMR Experiments on Organocobalt(I) Catalysts. Chemphyschem 2018; 19:227-236. [PMID: 29120533 DOI: 10.1002/cphc.201700990] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/08/2017] [Indexed: 11/07/2022]
Abstract
A series of fumarate-based organocobalt(I) [CoCp(CO)(fumarate)] catalysts is synthesized and characterized by X-ray crystallography, multinuclear (13 C and 59 Co) solid-state NMR spectroscopy, and 59 Co NQR spectroscopy. Given the dearth of 59 Co solid-state NMR studies on CoI compounds, the present work constitutes the first systematic characterization of the 59 Co electric field gradient and chemical shift tensors for a series of cobalt complexes in this oxidation state. Using X-ray crystallography, the molecular geometry about the CoI centre is found to be nearly identical in all compounds studied herein. Owing to the 59 Co nucleus' large chemical shift range, solid-state NMR experiments are found to be able to detect small structural differences between the individual organocobalt(I) compounds. With the aid of density functional theory calculations on these complexes, it is shown that the 59 Co chemical shift anisotropy and the 59 Co quadrupolar coupling constant are both extremely sensitive gauges of the Fu-Co-Cp bond angle, providing a link between these 59 Co NMR observables and the catalysts' structures.
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Affiliation(s)
- Kevin M N Burgess
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
- Current address: St. Peter's Seminary, University of Western Ontario, 1040 Waterloo St., London, ON, N6A 3Y1, Canada
| | - Cory M Widdifield
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
- Current address: Oakland University, Department of Chemistry, Mathematics and Science Center, 146 Library Drive, Rochester, MI, 48309-4479, USA
| | - Yang Xu
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
| | - César Leroy
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
| | - David L Bryce
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
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31
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Lilly Thankamony AS, Wittmann JJ, Kaushik M, Corzilius B. Dynamic nuclear polarization for sensitivity enhancement in modern solid-state NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 102-103:120-195. [PMID: 29157490 DOI: 10.1016/j.pnmrs.2017.06.002] [Citation(s) in RCA: 278] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/03/2017] [Accepted: 06/08/2017] [Indexed: 05/03/2023]
Abstract
The field of dynamic nuclear polarization has undergone tremendous developments and diversification since its inception more than 6 decades ago. In this review we provide an in-depth overview of the relevant topics involved in DNP-enhanced MAS NMR spectroscopy. This includes the theoretical description of DNP mechanisms as well as of the polarization transfer pathways that can lead to a uniform or selective spreading of polarization between nuclear spins. Furthermore, we cover historical and state-of-the art aspects of dedicated instrumentation, polarizing agents, and optimization techniques for efficient MAS DNP. Finally, we present an extensive overview on applications in the fields of structural biology and materials science, which underlines that MAS DNP has moved far beyond the proof-of-concept stage and has become an important tool for research in these fields.
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Affiliation(s)
- Aany Sofia Lilly Thankamony
- Institute of Physical and Theoretical Chemistry, Institute of Biophysical Chemistry, and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Johannes J Wittmann
- Institute of Physical and Theoretical Chemistry, Institute of Biophysical Chemistry, and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Monu Kaushik
- Institute of Physical and Theoretical Chemistry, Institute of Biophysical Chemistry, and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Björn Corzilius
- Institute of Physical and Theoretical Chemistry, Institute of Biophysical Chemistry, and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany.
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32
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Ravera E, Parigi G, Luchinat C. Perspectives on paramagnetic NMR from a life sciences infrastructure. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 282:154-169. [PMID: 28844254 DOI: 10.1016/j.jmr.2017.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 07/31/2017] [Indexed: 05/17/2023]
Abstract
The effects arising in NMR spectroscopy because of the presence of unpaired electrons, collectively referred to as "paramagnetic NMR" have attracted increasing attention over the last decades. From the standpoint of the structural and mechanistic biology, paramagnetic NMR provides long range restraints that can be used to assess the accuracy of crystal structures in solution and to improve them by simultaneous refinements through NMR and X-ray data. These restraints also provide information on structure rearrangements and conformational variability in biomolecular systems. Theoretical improvements in quantum chemistry calculations can nowadays allow for accurate calculations of the paramagnetic data from a molecular structural model, thus providing a tool to refine the metal coordination environment by matching the paramagnetic effects observed far away from the metal. Furthermore, the availability of an improved technology (higher fields and faster magic angle spinning) has promoted paramagnetic NMR applications in the fast-growing area of biomolecular solid-state NMR. Major improvements in dynamic nuclear polarization have been recently achieved, especially through the exploitation of the Overhauser effect occurring through the contact-driven relaxation mechanism: the very large enhancement of the 13C signal observed in a variety of liquid organic compounds at high fields is expected to open up new perspectives for applications of solution NMR.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy.
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33
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Perras FA, Sadow A, Pruski M. In Silico Design of DNP Polarizing Agents: Can Current Dinitroxides Be Improved? Chemphyschem 2017; 18:2279-2287. [DOI: 10.1002/cphc.201700299] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/07/2017] [Indexed: 12/18/2022]
Affiliation(s)
| | - Aaron Sadow
- US DOE Ames Laboratory Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
| | - Marek Pruski
- US DOE Ames Laboratory Ames IA 50011 USA
- Department of Chemistry Iowa State University Ames IA 50011 USA
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34
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Ravera E, Martelli T, Geiger Y, Fragai M, Goobes G, Luchinat C. Biosilica and bioinspired silica studied by solid-state NMR. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.06.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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35
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Abstract
The structure and dynamics of the bound water in barium chlorate monohydrate were studied with (17)O nuclear magnetic resonance (NMR) spectroscopy in samples that are stationary and spinning at the magic-angle in magnetic fields ranging from 14.1 to 21.1 T. (17)O NMR parameters of the water were determined, and the effects of torsional oscillations of the water molecule on the (17)O quadrupolar coupling constant (CQ) were delineated with variable temperature MAS NMR. With decreasing temperature and reduction of the librational motion, we observe an increase in the experimentally measured CQ explaining the discrepancy between experiments and predictions from density functional theory. In addition, at low temperatures and in the absence of (1)H decoupling, we observe a well-resolved (1)H-(17)O dipole splitting in the spectra, which provides information on the structure of the H2O molecule. The splitting arises because of the homogeneous nature of the coupling between the two (1)H-(17)O dipoles and the (1)H-(1)H dipole.
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Affiliation(s)
- Eric G. Keeler
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | | | - Robert G. Griffin
- Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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36
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Geiger Y, Gottlieb HE, Akbey Ü, Oschkinat H, Goobes G. Studying the Conformation of a Silaffin-Derived Pentalysine Peptide Embedded in Bioinspired Silica using Solution and Dynamic Nuclear Polarization Magic-Angle Spinning NMR. J Am Chem Soc 2016; 138:5561-7. [DOI: 10.1021/jacs.5b07809] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yasmin Geiger
- Department
of Chemistry, Bar Ilan University, Ramat Gan 52900, Israel
| | - Hugo E. Gottlieb
- Department
of Chemistry, Bar Ilan University, Ramat Gan 52900, Israel
| | - Ümit Akbey
- Leibniz Institute für Molekulare Pharmakologie (FMP), NMR Supported Structural Biology, Robert-Roessle-Str.
10, Berlin 13125, Germany
| | - Hartmut Oschkinat
- Leibniz Institute für Molekulare Pharmakologie (FMP), NMR Supported Structural Biology, Robert-Roessle-Str.
10, Berlin 13125, Germany
| | - Gil Goobes
- Department
of Chemistry, Bar Ilan University, Ramat Gan 52900, Israel
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37
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Fataftah MS, Zadrozny JM, Coste SC, Graham MJ, Rogers DM, Freedman DE. Employing Forbidden Transitions as Qubits in a Nuclear Spin-Free Chromium Complex. J Am Chem Soc 2016; 138:1344-8. [DOI: 10.1021/jacs.5b11802] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Majed S. Fataftah
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Joseph M. Zadrozny
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Scott C. Coste
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Michael J. Graham
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Dylan M. Rogers
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Danna E. Freedman
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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38
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Smith AN, Long JR. Dynamic Nuclear Polarization as an Enabling Technology for Solid State Nuclear Magnetic Resonance Spectroscopy. Anal Chem 2016; 88:122-32. [PMID: 26594903 PMCID: PMC5704910 DOI: 10.1021/acs.analchem.5b04376] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Adam N Smith
- Department of Chemistry, University of Florida , 214 Leigh Hall, Gainesville, Florida 32611-7200, United States
| | - Joanna R Long
- Department of Biochemistry and Molecular Biology, University of Florida , P. O. Box 100245, Gainesville, Florida 32610-0245, United States
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39
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Corzilius B. Theory of solid effect and cross effect dynamic nuclear polarization with half-integer high-spin metal polarizing agents in rotating solids. Phys Chem Chem Phys 2016; 18:27190-27204. [DOI: 10.1039/c6cp04621e] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Detailed theoretical description of high-spin properties of metal polarizing agents, especially Gd3+, for solid effect and cross effect DNP.
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Affiliation(s)
- Björn Corzilius
- Institute of Physical and Theoretical Chemistry
- Institute of Biophysical Chemistry, and Center for Biomolecular Magnetic Resonance (BMRZ)
- Goethe University Frankfurt
- 60438 Frankfurt am Main
- Germany
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40
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Zhang Y, Baker PJ, Casabianca LB. BDPA-Doped Polystyrene Beads as Polarization Agents for DNP-NMR. J Phys Chem B 2015; 120:18-24. [PMID: 26717243 DOI: 10.1021/acs.jpcb.5b08741] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The aromatic free radical BDPA (α,γ-bisdiphenylene-β-phenylallyl), which has been widely used as a polarizing agent for Dynamic Nuclear Polarization (DNP) of hydrophobic analytes, has been incorporated into nanometer-scale polystyrene latex beads. We have shown that the resulting BDPA-doped beads can be used to hyperpolarize (13)C and (7)Li nuclei in aqueous environments, without the need for a glassing cosolvent. DNP enhancement factors of between 20 and 100 were achieved with overall BDPA concentrations of 2 mM or less. These Highly-Effective Polymer/Radical Beads (HYPR-beads) have potential use as an inexpensive polarizing agent for water-soluble analytes, and also have applications as model nanoparticles in DNP studies.
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Affiliation(s)
- Yunzhi Zhang
- Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States
| | - Phillip J Baker
- Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States
| | - Leah B Casabianca
- Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States
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41
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Kobayashi T, Perras FA, Slowing II, Sadow AD, Pruski M. Dynamic Nuclear Polarization Solid-State NMR in Heterogeneous Catalysis Research. ACS Catal 2015. [DOI: 10.1021/acscatal.5b02039] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Igor I. Slowing
- U.S.
DOE Ames
Laboratory, Ames, Iowa 50011-3020, United States
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011-3020, United States
| | - Aaron D. Sadow
- U.S.
DOE Ames
Laboratory, Ames, Iowa 50011-3020, United States
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011-3020, United States
| | - Marek Pruski
- U.S.
DOE Ames
Laboratory, Ames, Iowa 50011-3020, United States
- Department
of Chemistry, Iowa State University, Ames, Iowa 50011-3020, United States
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42
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Piveteau L, Ong TC, Rossini AJ, Emsley L, Copéret C, Kovalenko MV. Structure of Colloidal Quantum Dots from Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy. J Am Chem Soc 2015; 137:13964-71. [PMID: 26473384 DOI: 10.1021/jacs.5b09248] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Understanding the chemistry of colloidal quantum dots (QDs) is primarily hampered by the lack of analytical methods to selectively and discriminately probe the QD core, QD surface and capping ligands. Here, we present a general concept for studying a broad range of QDs such as CdSe, CdTe, InP, PbSe, PbTe, CsPbBr3, etc., capped with both organic and inorganic surface capping ligands, through dynamic nuclear polarization (DNP) surface enhanced NMR spectroscopy. DNP can enhance NMR signals by factors of 10-100, thereby reducing the measurement times by 2-4 orders of magnitude. 1D DNP enhanced spectra acquired in this way are shown to clearly distinguish QD surface atoms from those of the QD core, and environmental effects such as oxidation. Furthermore, 2D NMR correlation experiments, which were previously inconceivable for QD surfaces, are demonstrated to be readily performed with DNP and provide the bonding motifs between the QD surfaces and the capping ligands.
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Affiliation(s)
- Laura Piveteau
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, Zürich CH-8093, Switzerland.,Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Dübendorf CH-8600, Switzerland
| | - Ta-Chung Ong
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, Zürich CH-8093, Switzerland
| | - Aaron J Rossini
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, Zürich CH-8093, Switzerland
| | - Maksym V Kovalenko
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir Prelog Weg 1-5, Zürich CH-8093, Switzerland.,Empa-Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, Dübendorf CH-8600, Switzerland
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43
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Ravera E, Michaelis VK, Ong TC, Keeler EG, Martelli T, Fragai M, Griffin RG, Luchinat C. Biosilica-Entrapped Enzymes Studied by Using Dynamic Nuclear-Polarization-Enhanced High-Field NMR Spectroscopy. Chemphyschem 2015; 16:2751-2754. [PMID: 26266832 PMCID: PMC4752418 DOI: 10.1002/cphc.201500549] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Indexed: 11/08/2022]
Abstract
Enzymes are used as environmentally friendly catalysts in many industrial applications, and are frequently immobilized in a matrix to improve their chemical stability for long-term storage and reusability. Recently, it was shown that an atomic-level description of proteins immobilized in a biosilica matrix can be attained by examining their magic-angle spinning (MAS) NMR spectra. However, even though MAS NMR is an excellent tool for determining structure, it is severely hampered by sensitivity. In this work we provide the proof of principle that NMR characterization of biosilica-entrapped enzymes could be assisted by high-field dynamic nuclear polarization (DNP).
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, 50019 Sesto Fiorentino (FI), Italy
| | - Vladimir K. Michaelis
- Francis Bitter Magnet Laboratory and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ta-Chung Ong
- Francis Bitter Magnet Laboratory and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Eric G. Keeler
- Francis Bitter Magnet Laboratory and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Tommaso Martelli
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, 50019 Sesto Fiorentino (FI), Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, 50019 Sesto Fiorentino (FI), Italy
| | - Robert G. Griffin
- Francis Bitter Magnet Laboratory and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, 50019 Sesto Fiorentino (FI), Italy
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44
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Ardenkjaer-Larsen JH, Boebinger GS, Comment A, Duckett S, Edison AS, Engelke F, Griesinger C, Griffin RG, Hilty C, Maeda H, Parigi G, Prisner T, Ravera E, van Bentum J, Vega S, Webb A, Luchinat C, Schwalbe H, Frydman L. Facing and Overcoming Sensitivity Challenges in Biomolecular NMR Spectroscopy. Angew Chem Int Ed Engl 2015; 54:9162-85. [PMID: 26136394 PMCID: PMC4943876 DOI: 10.1002/anie.201410653] [Citation(s) in RCA: 217] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/26/2015] [Indexed: 11/07/2022]
Abstract
In the Spring of 2013, NMR spectroscopists convened at the Weizmann Institute in Israel to brainstorm on approaches to improve the sensitivity of NMR experiments, particularly when applied in biomolecular settings. This multi-author interdisciplinary Review presents a state-of-the-art description of the primary approaches that were considered. Topics discussed included the future of ultrahigh-field NMR systems, emerging NMR detection technologies, new approaches to nuclear hyperpolarization, and progress in sample preparation. All of these are orthogonal efforts, whose gains could multiply and thereby enhance the sensitivity of solid- and liquid-state experiments. While substantial advances have been made in all these areas, numerous challenges remain in the quest of endowing NMR spectroscopy with the sensitivity that has characterized forms of spectroscopies based on electrical or optical measurements. These challenges, and the ways by which scientists and engineers are striving to solve them, are also addressed.
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Affiliation(s)
- Jan-Henrik Ardenkjaer-Larsen
- GE Healthcare, Broendby, Denmark; Department of Electrical Engineering, Technical University of Denmark, Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre (Denmark)
| | - Gregory S Boebinger
- U.S. National High Magnetic Field Lab, Florida State University, Tallahassee, FL 32310 (USA)
| | - Arnaud Comment
- Institute of Physics of Biological Systems, Ecole Polytechnique Fédérale de Lausanne, Lausanne (Switzerland)
| | - Simon Duckett
- Department of Chemistry, University of York, Heslington, York, YO10 5DD (UK)
| | - Arthur S Edison
- Department of Biochemistry & Molecular Biology, University of Florida, Gainesville, FL 32610 (USA)
| | | | | | - Robert G Griffin
- Department of Chemistry and Francis Bitter Magnet Lab, MIT, Cambridge, MA 02139-4703 (USA)
| | - Christian Hilty
- Department of Chemistry, Texas A&M University, College Station (USA)
| | - Hidaeki Maeda
- Riken Center for Life Science Technologies, Yokohama, Kanagawa (Japan)
| | - Giacomo Parigi
- CERM and Department of Chemistry, University of Florence, Sesto Fiorentino (Italy)
| | - Thomas Prisner
- Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main (Germany)
| | - Enrico Ravera
- CERM and Department of Chemistry, University of Florence, Sesto Fiorentino (Italy)
| | | | - Shimon Vega
- Chemical Physics Department, Weizmann Institute of Science, Rehovot (Israel)
| | - Andrew Webb
- Department of Radiology, C. J. Gorter Center for High Field MRI, Leiden University Medical Center (The Netherlands)
| | - Claudio Luchinat
- CERM and Department of Chemistry, University of Florence, Sesto Fiorentino (Italy).
| | - Harald Schwalbe
- Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main (Germany).
| | - Lucio Frydman
- Chemical Physics Department, Weizmann Institute of Science, Rehovot (Israel).
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Ardenkjaer-Larsen JH, Boebinger GS, Comment A, Duckett S, Edison AS, Engelke F, Griesinger C, Griffin RG, Hilty C, Maeda H, Parigi G, Prisner T, Ravera E, van Bentum J, Vega S, Webb A, Luchinat C, Schwalbe H, Frydman L. Neue Ansätze zur Empfindlichkeitssteigerung in der biomolekularen NMR-Spektroskopie. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201410653] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Lee D, Hediger S, De Paëpe G. Is solid-state NMR enhanced by dynamic nuclear polarization? SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 66-67:6-20. [PMID: 25779337 DOI: 10.1016/j.ssnmr.2015.01.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 05/03/2023]
Abstract
The recent trend of high-field (~5-20 T), low-temperature (~100 K) ssNMR combined with dynamic nuclear polarization (DNP) under magic angle spinning (MAS) conditions is analyzed. A brief overview of the current theory of hyperpolarization for so-called MAS-DNP experiments is given, along with various reasons why the DNP-enhancement, the ratio of the NMR signal intensities obtained in the presence and absence of microwave irradiation suitable for hyperpolarization, should not be used alone to gauge the value of performing MAS-DNP experiments relative to conventional ssNMR. This is demonstrated through a dissection of the current conditions required for MAS-DNP with particular attention to resulting absolute sensitivities and spectral resolution. Consequently, sample preparation methods specifically avoiding the surplus of glass-forming solvents so as to improve the absolute sensitivity and resolution are discussed, as are samples that are intrinsically pertinent for MAS-DNP studies (high surface area, amorphous, and porous). Owing to their pertinence, examples of recent applications on these types of samples where chemically-relevant information has been obtained that would have been impossible without the sensitivity increases bestowed by MAS-DNP are also detailed. Additionally, a promising further implementation for MAS-DNP is exampled, whereby the sensitivity improvements shown for (correlation) spectroscopy of nuclei at low natural isotopic abundance, facilitate internuclear distance measurements, especially for long distances (absence of dipolar truncation). Finally, we give some speculative perspectives for MAS-DNP.
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Affiliation(s)
- Daniel Lee
- Univ. Grenoble Alpes, INAC, SCIB, F-38000 Grenoble, France; CEA, INAC, SCIB, F-38000 Grenoble, France.
| | - Sabine Hediger
- Univ. Grenoble Alpes, INAC, SCIB, F-38000 Grenoble, France; CEA, INAC, SCIB, F-38000 Grenoble, France; CNRS, SCIB, F-38000 Grenoble, France
| | - Gaël De Paëpe
- Univ. Grenoble Alpes, INAC, SCIB, F-38000 Grenoble, France; CEA, INAC, SCIB, F-38000 Grenoble, France
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47
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Ravera E, Shimon D, Feintuch A, Goldfarb D, Vega S, Flori A, Luchinat C, Menichetti L, Parigi G. The effect of Gd on trityl-based dynamic nuclear polarisation in solids. Phys Chem Chem Phys 2015; 17:26969-78. [DOI: 10.1039/c5cp04138d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The increase in 13C polarisation of 13C-urea dissolved in samples containing water/DMSO mixtures and trityl radical (OX063) in the presence of Gd3+ is explained by changes in electron relaxation, electron spectral diffusion and effective electron–proton hyperfine interaction.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”
- University of Florence
- Italy
| | - Daphna Shimon
- Chemical Physics Department
- Weizmann Institute of Science
- Rehovot
- Israel
| | - Akiva Feintuch
- Chemical Physics Department
- Weizmann Institute of Science
- Rehovot
- Israel
| | - Daniella Goldfarb
- Chemical Physics Department
- Weizmann Institute of Science
- Rehovot
- Israel
| | - Shimon Vega
- Chemical Physics Department
- Weizmann Institute of Science
- Rehovot
- Israel
| | - Alessandra Flori
- Fondazione CNR/Regione Toscana G. Monasterio and Institute of Life Sciences
- Scuola Superiore Sant'Anna
- Pisa
- Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”
- University of Florence
- Italy
| | - Luca Menichetti
- Fondazione CNR/Regione Toscana G. Monasterio and Institute of Clinical Physiology
- National Council of Research
- Pisa
- Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”
- University of Florence
- Italy
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Pan D, Xu Q, Dong Z, Chen S, Yu F, Yan X, Fan B, Li R. Facile synthesis of highly ordered mesoporous cobalt–alumina catalysts and their application in liquid phase selective oxidation of styrene. RSC Adv 2015. [DOI: 10.1039/c5ra20531j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We illustrate the preparation of highly ordered mesoporous cobalt–alumina catalysts with highly homogeneously dispersed Co(ii) species via an evaporation-induced triconstituent cooperative co-assembly method.
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Affiliation(s)
- Dahai Pan
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Qian Xu
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Zhaoyang Dong
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Shuwei Chen
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Feng Yu
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Xiaoliang Yan
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Binbin Fan
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
| | - Ruifeng Li
- The Research Center of Chemical Technology & Catalysis for Energy
- College of Chemistry and Chemical Engineering
- Taiyuan University of Technology
- Taiyuan 030024
- China
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