The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Marek Pruski - One of the best experts on this subject based on the ideXlab platform.
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Chapter 1:Heteronuclear Correlation Solid-state NMR Spectroscopy with Indirect Detection under Fast Magic-angle Spinning
Modern Methods in Solid-state NMR, 2018Co-Authors: Takeshi Kobayashi, Yusuke Nishiyama, Marek PruskiAbstract:The development of probes capable of magic-angle spinning (MAS) at very high rates, which now exceed 100 kHz, has revolutionized solid-state NMR spectroscopy. The introductory parts of this chapter describe the basic aspects of fast MAS and illuminate the main advantages of this remarkable technology. Thereafter, practical advice is given on the use and maintenance of fast MAS instrumentation. The bulk of the text, however, describes the principles and hands-on aspects of Heteronuclear Correlation (HETCOR) experiments performed under fast MAS with indirect detection of lower-γ nuclei. We specifically focus on experimental strategies used in our laboratories to optimize the pulse sequences akin to the HSQC and HMQC experiments known in solution NMR. The HSQC scheme can be used to measure the spectra of dilute lower-γ spin-1/2 nuclei, while the HMQC sequence is best suited to measure spectra that are broadened by the quadrupolar interaction or large chemical shift anisotropy. Numerous through-space and through-bond 1H{13C}, 1H{15N} and 1H{14N} HETCOR spectra are presented to demonstrate the resolution and sensitivity benefits of indirect detection and illustrate the optimization strategies. We hope that these examples will showcase the merits of indirect detection and encourage the readers to make the most of these experiments.
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improved strategies for dnp enhanced 2d 1h x Heteronuclear Correlation spectroscopy of surfaces
Solid State Nuclear Magnetic Resonance, 2017Co-Authors: Takeshi Kobayashi, Frederic A Perras, Umesh Chaudhary, Igor I Slowing, Wenyu Huang, Aaron D Sadow, Marek PruskiAbstract:We demonstrate that dynamic nuclear polarization (DNP)-enhanced 1H-X Heteronuclear Correlation (HETCOR) measurements of hydrogen-rich surface species are better accomplished by using proton-free solvents. This approach notably prevents HETCOR spectra from being obfuscated by the solvent-derived signals otherwise present in DNP measurements. Additionally, in the hydrogen-rich materials studied here, which included functionalized mesoporous silica nanoparticles and metal organic frameworks, the use of proton-free solvents afforded higher sensitivity gains than the commonly used solvents containing protons. We also explored the possibility of using a solvent-free sample formulation and the feasibility of indirect detection in DNP-enhanced HETCOR experiments.
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studies of minute quantities of natural abundance molecules using 2d Heteronuclear Correlation spectroscopy under 100 khz mas
Solid State Nuclear Magnetic Resonance, 2015Co-Authors: Yusuke Nishiyama, Marek Pruski, Takeshi Kobayashi, Igor I Slowing, Michal Malon, Dilini SingappuliarachchigeAbstract:Abstract Two-dimensional 1 H{ 13 C} Heteronuclear Correlation solid-state NMR spectra of naturally abundant solid materials are presented, acquired using the 0.75-mm magic angle spinning (MAS) probe at spinning rates up to 100 kHz. In spite of the miniscule sample volume (290 nL), high-quality HSQC-type spectra of bulk samples as well as surface-bound molecules can be obtained within hours of experimental time. The experiments are compared with those carried out at 40 kHz MAS using a 1.6-mm probe, which offered higher overall sensitivity due to a larger rotor volume. The benefits of ultrafast MAS in such experiments include superior resolution in 1 H dimension without resorting to 1 H– 1 H homonuclear RF decoupling, easy optimization, and applicability to mass-limited samples. The HMQC spectra of surface-bound species can be also acquired under 100 kHz MAS, although the dephasing of transverse magnetization has significant effect on the efficiency transfer under MAS alone.
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indirectly detected Heteronuclear Correlation solid state nmr spectroscopy of naturally abundant 15n nuclei
Solid State Nuclear Magnetic Resonance, 2014Co-Authors: Marek Pruski, Takeshi Kobayashi, Stacey M Althaus, John StringerAbstract:Abstract Two-dimensional indirectly detected through-space and through-bond 1 H{ 15 N} solid-state NMR experiments utilizing fast magic angle spinning (MAS) and homonuclear multipulse 1 H decoupling are evaluated. Remarkable efficiency of polarization transfer can be achieved at a MAS rate of 40 kHz by both cross-polarization and INEPT, which makes these methods applicable for routine characterizations of natural abundance solids. The first measurement of 2D 1 H{ 15 N} HETCOR spectrum of natural abundance surface species is also reported.
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Study of intermolecular interactions in the corrole matrix by solid-state NMR under 100 kHz MAS and theoretical calculations
Angewandte Chemie - International Edition, 2013Co-Authors: Takeshi Kobayashi, Kanmi Mao, Agnieszka Nowak-krõl, Justyna Sniechowska, Piotr Paluch, Marek J. Potrzebowski, Daniel T Gryko, Yusuke Nishiyama, Marek PruskiAbstract:A combination of solid-state NMR techniques and theoretical calculations confirmed that unsubstituted metal-free corroles form supramolecular systems with toluene through π-π interactions in the solid state. Ultrafast magic angle spinning (MAS) enabled the use of (1) H-(1) H homonuclear Correlation spectroscopy to explore those intermolecular interactions for which Heteronuclear Correlation methods were difficult to apply.
Takeshi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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Chapter 1:Heteronuclear Correlation Solid-state NMR Spectroscopy with Indirect Detection under Fast Magic-angle Spinning
Modern Methods in Solid-state NMR, 2018Co-Authors: Takeshi Kobayashi, Yusuke Nishiyama, Marek PruskiAbstract:The development of probes capable of magic-angle spinning (MAS) at very high rates, which now exceed 100 kHz, has revolutionized solid-state NMR spectroscopy. The introductory parts of this chapter describe the basic aspects of fast MAS and illuminate the main advantages of this remarkable technology. Thereafter, practical advice is given on the use and maintenance of fast MAS instrumentation. The bulk of the text, however, describes the principles and hands-on aspects of Heteronuclear Correlation (HETCOR) experiments performed under fast MAS with indirect detection of lower-γ nuclei. We specifically focus on experimental strategies used in our laboratories to optimize the pulse sequences akin to the HSQC and HMQC experiments known in solution NMR. The HSQC scheme can be used to measure the spectra of dilute lower-γ spin-1/2 nuclei, while the HMQC sequence is best suited to measure spectra that are broadened by the quadrupolar interaction or large chemical shift anisotropy. Numerous through-space and through-bond 1H{13C}, 1H{15N} and 1H{14N} HETCOR spectra are presented to demonstrate the resolution and sensitivity benefits of indirect detection and illustrate the optimization strategies. We hope that these examples will showcase the merits of indirect detection and encourage the readers to make the most of these experiments.
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improved strategies for dnp enhanced 2d 1h x Heteronuclear Correlation spectroscopy of surfaces
Solid State Nuclear Magnetic Resonance, 2017Co-Authors: Takeshi Kobayashi, Frederic A Perras, Umesh Chaudhary, Igor I Slowing, Wenyu Huang, Aaron D Sadow, Marek PruskiAbstract:We demonstrate that dynamic nuclear polarization (DNP)-enhanced 1H-X Heteronuclear Correlation (HETCOR) measurements of hydrogen-rich surface species are better accomplished by using proton-free solvents. This approach notably prevents HETCOR spectra from being obfuscated by the solvent-derived signals otherwise present in DNP measurements. Additionally, in the hydrogen-rich materials studied here, which included functionalized mesoporous silica nanoparticles and metal organic frameworks, the use of proton-free solvents afforded higher sensitivity gains than the commonly used solvents containing protons. We also explored the possibility of using a solvent-free sample formulation and the feasibility of indirect detection in DNP-enhanced HETCOR experiments.
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studies of minute quantities of natural abundance molecules using 2d Heteronuclear Correlation spectroscopy under 100 khz mas
Solid State Nuclear Magnetic Resonance, 2015Co-Authors: Yusuke Nishiyama, Marek Pruski, Takeshi Kobayashi, Igor I Slowing, Michal Malon, Dilini SingappuliarachchigeAbstract:Abstract Two-dimensional 1 H{ 13 C} Heteronuclear Correlation solid-state NMR spectra of naturally abundant solid materials are presented, acquired using the 0.75-mm magic angle spinning (MAS) probe at spinning rates up to 100 kHz. In spite of the miniscule sample volume (290 nL), high-quality HSQC-type spectra of bulk samples as well as surface-bound molecules can be obtained within hours of experimental time. The experiments are compared with those carried out at 40 kHz MAS using a 1.6-mm probe, which offered higher overall sensitivity due to a larger rotor volume. The benefits of ultrafast MAS in such experiments include superior resolution in 1 H dimension without resorting to 1 H– 1 H homonuclear RF decoupling, easy optimization, and applicability to mass-limited samples. The HMQC spectra of surface-bound species can be also acquired under 100 kHz MAS, although the dephasing of transverse magnetization has significant effect on the efficiency transfer under MAS alone.
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indirectly detected Heteronuclear Correlation solid state nmr spectroscopy of naturally abundant 15n nuclei
Solid State Nuclear Magnetic Resonance, 2014Co-Authors: Marek Pruski, Takeshi Kobayashi, Stacey M Althaus, John StringerAbstract:Abstract Two-dimensional indirectly detected through-space and through-bond 1 H{ 15 N} solid-state NMR experiments utilizing fast magic angle spinning (MAS) and homonuclear multipulse 1 H decoupling are evaluated. Remarkable efficiency of polarization transfer can be achieved at a MAS rate of 40 kHz by both cross-polarization and INEPT, which makes these methods applicable for routine characterizations of natural abundance solids. The first measurement of 2D 1 H{ 15 N} HETCOR spectrum of natural abundance surface species is also reported.
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Study of intermolecular interactions in the corrole matrix by solid-state NMR under 100 kHz MAS and theoretical calculations
Angewandte Chemie - International Edition, 2013Co-Authors: Takeshi Kobayashi, Kanmi Mao, Agnieszka Nowak-krõl, Justyna Sniechowska, Piotr Paluch, Marek J. Potrzebowski, Daniel T Gryko, Yusuke Nishiyama, Marek PruskiAbstract:A combination of solid-state NMR techniques and theoretical calculations confirmed that unsubstituted metal-free corroles form supramolecular systems with toluene through π-π interactions in the solid state. Ultrafast magic angle spinning (MAS) enabled the use of (1) H-(1) H homonuclear Correlation spectroscopy to explore those intermolecular interactions for which Heteronuclear Correlation methods were difficult to apply.
Chad M Rienstra - One of the best experts on this subject based on the ideXlab platform.
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J-based 2D homonuclear and Heteronuclear Correlation in solid-state proteins.
Magnetic resonance in chemistry : MRC, 2020Co-Authors: Lingling Chen, Tatyana Polenova, Jun Yang, Chad M Rienstra, J Michael Kaiser, Leonard J MuellerAbstract:Scalar-based two-dimensional Heteronuclear experiments are reported for NCO and NCA chemical shift Correlation in the solid state. In conjunction with homonuclear CACO Correlation, these experiments form a useful set for tracing connectivities and assigning backbone resonances in solid-state proteins. The applicability of this approach is demonstrated on two proteins, the β 1 immunoglobulin binding domain of protein G at 9.4 T and reassembled thioredoxin at 14.1 T, using different decoupling conditions and MAS frequencies. These constant-time J-based Correlation experiments exhibit increased resolution in the indirect dimension owing to homonuclear and Heteronuclear decoupling, and because the indirect evolution and transfer periods are combined into a single constant time interval, this increased resolution is not obtained at the cost of sensitivity. These experiments are also shown to be compatible with in-phase anti-phase (IPAP) selection, giving increased resolution in the directly detected dimension.
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j based 2d homonuclear and Heteronuclear Correlation in solid state proteins
Magnetic Resonance in Chemistry, 2007Co-Authors: Lingling Chen, Tatyana Polenova, Michael J Kaiser, Jun Yang, Chad M Rienstra, Leonard J MuellerAbstract:Scalar-based two-dimensional Heteronuclear experiments are reported for NCO and NCA chemical shift Correlation in the solid state. In conjunction with homonuclear CACO Correlation, these experiments form a useful set for tracing connectivities and assigning backbone resonances in solid-state proteins. The applicability of this approach is demonstrated on two proteins, the β 1 immunoglobulin binding domain of protein G at 9.4 T and reassembled thioredoxin at 14.1 T, using different decoupling conditions and MAS frequencies. These constant-time J-based Correlation experiments exhibit increased resolution in the indirect dimension owing to homonuclear and Heteronuclear decoupling, and because the indirect evolution and transfer periods are combined into a single constant time interval, this increased resolution is not obtained at the cost of sensitivity. These experiments are also shown to be compatible with in-phase anti-phase (IPAP) selection, giving increased resolution in the directly detected dimension. Copyright © 2007 John Wiley & Sons, Ltd.
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backbone assignments in solid state proteins using j based 3d Heteronuclear Correlation spectroscopy
Journal of the American Chemical Society, 2007Co-Authors: Lingling Chen, Tatyana Polenova, Michael J Kaiser, Jun Yang, Chad M Rienstra, Leonard J MuellerAbstract:3D NCACO, NCOCA, and CANCO scalar-coupling driven Correlation experiments are presented for protein backbone assignments in the solid-state. These J-MAS experiments show superior resolution in the indirect dimensions through the elimination of Heteronuclear and homonuclear couplings and enhanced sensitivity, which allow us to trace out the entire protein backbone for GB1. Our results demonstrate that scalar-based methods are sufficiently well-developed to serve as a complementary tool to dipolar methods, which will be especially useful for assignment of large proteins, where resonance overlap presents a major challenge to solid-state NMR.
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four dimensional Heteronuclear Correlation experiments for chemical shift assignment of solid proteins
Journal of Biomolecular NMR, 2007Co-Authors: Trent W Franks, Kathryn D Kloepper, Benjamin J Wylie, Chad M RienstraAbstract:Chemical shift assignment is the first step in all established protocols for structure determination of uniformly labeled proteins by NMR. The explosive growth in recent years of magic-angle spinning (MAS) solid-state NMR (SSNMR) applications is largely attributable to improved methods for backbone and side-chain chemical shift Correlation spectroscopy. However, the techniques developed so far have been applied primarily to proteins in the size range of 5–10 kDa, despite the fact that SSNMR has no inherent molecular weight limits. Rather, the degeneracy inherent to many 2D and 3D SSNMR spectra of larger proteins has prevented complete unambiguous chemical shift assignment. Here we demonstrate the implementation of 4D backbone chemical shift Correlation experiments for assignment of solid proteins. The experiments greatly reduce spectral degeneracy at a modest cost in sensitivity, which is accurately described by theory. We consider several possible implementations and investigate the CANCOCX pulse sequence in detail. This experiment involves three cross polarization steps, from H to CA[i], CA[i] to N[i], and N[i] to C′[i−1], followed by a final homonuclear mixing period. With short homonuclear mixing times ( 200 ms), long-range Correlations are revealed. For example, a single 4D experiment with 225 ms homonuclear mixing time reveals ∼200 uniquely resolved medium and long-range Correlations in the 56-residue protein GB1. In addition to experimental demonstrations in the 56-residue protein GB1, we present a theoretical analysis of anticipated improvements in resolution for much larger proteins and compare these results in detail with the experiments, finding good agreement between experiment and theory under conditions of stable instrumental performance.
Ole W Sorensen - One of the best experts on this subject based on the ideXlab platform.
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bango sea xloc hmbc h2obc complete Heteronuclear Correlation within minutes from one nmr pulse sequence
Chemical Communications, 2019Co-Authors: Tamas Milan Nagy, Tamas Gyongyosi, Katalin E Kover, Ole W SorensenAbstract:Novel NMR experiments, BANGO SEA XLOC–H2OBC or BANGO HMBC–H2OBC, can deliver complete Heteronuclear Correlation maps on a time scale of minutes for small molecules. By way of example, it is demonstrated that all intra- and inter-residue 1H and 13C Correlations and assignments of a trisaccharide are obtained in 20 or 5 minutes of instrument time without or with 25% NUS, respectively.
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BANGO SEA XLOC/HMBC-H2OBC: complete Heteronuclear Correlation within minutes from one NMR pulse sequence.
Chemical Communications, 2019Co-Authors: Tamas Milan Nagy, Tamas Gyongyosi, Katalin E Kover, Ole W SorensenAbstract:Novel NMR experiments, BANGO SEA XLOC–H2OBC or BANGO HMBC–H2OBC, can deliver complete Heteronuclear Correlation maps on a time scale of minutes for small molecules. By way of example, it is demonstrated that all intra- and inter-residue 1H and 13C Correlations and assignments of a trisaccharide are obtained in 20 or 5 minutes of instrument time without or with 25% NUS, respectively.
Jean-paul Amoureux - One of the best experts on this subject based on the ideXlab platform.
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γ-Independent through-space hetero-nuclear Correlation between spin-1/2 and quadrupolar nuclei in solids.
Solid State Nuclear Magnetic Resonance, 2017Co-Authors: Hiroki Nagashima, Julien Trébosc, Aany Sofia Lilly Thankamony, Frédérique Pourpoint, Olivier Lafon, Jean-paul AmoureuxAbstract:Abstract We introduce novel sequences using indirect detection to correlate quadrupolar nuclei and spin-1/2 isotopes, other than 1H and 19F. These sequences use γ-encoded symmetry-based R N n ν schemes that reintroduce the space component |m| = 1 of the Heteronuclear dipolar coupling. These schemes can be applied to the indirectly detected spin in Dipolar-mediated Heteronuclear Multiple-Quantum Correlation (D-HMQC) sequence or to the detected isotope in a novel sequence, named Dipolar-mediated Heteronuclear Universal-Quantum Correlation (D-HUQC). We show that the signal of these sequences using γ-encoded recoupling does not depend on the γ Euler angle relating the inter-nuclear vector between the coupled spins to the MAS rotor-fixed frame. Therefore, the transfer efficiency of these sequences is in principle higher than that of D-HMQC methods using non-γ-encoded recoupling. Furthermore, numerical simulations show that the Heteronuclear Correlation experiments employing γ-encoded recoupling are more robust to Chemical Shift Anisotropy (CSA) of the irradiated spin and MAS frequency fluctuations. These results are confirmed by 13C-{15N} Heteronuclear Correlation on glycine and 31P-27Al ones on VPI-5 and Na7(AlP2O7)4PO4. These experiments indicate that R 16 3 5 recoupling produces the highest signal-to-noise ratio in Heteronuclear Correlation 2D experiments when the detected spin-1/2 nuclei are subject to large CSA.
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spam mq hetcor an improved method for Heteronuclear Correlation spectroscopy between quadrupolar and spin 1 2 nuclei in solid state nmr
Physical Chemistry Chemical Physics, 2006Co-Authors: Jerzy W Wiench, Julien Trébosc, Jean-paul Amoureux, Gregory Tricot, Laurent Delevoye, James Frye, Lionel Montagne, Marek PruskiAbstract:The recently introduced concept of soft pulse added mixing (SPAM) is used in two-dimensional Heteronuclear Correlation (HETCOR) NMR experiments between half-integer quadrupolar and spin-1/2 nuclei. The experiments employ multiple quantum magic angle spinning (MQMAS) to remove the second order quadrupolar broadening and cross polarization (CP) or refocused INEPT for magnetization transfer. By using previously unexploited coherence pathways, the efficiency of SPAM-MQ-HETCOR NMR is increased by a factor of almost two without additional optimization. The sensitivity gain is demonstrated on a test sample, AlPO4-14, using CP and INEPT to correlate 27Al and 31P nuclei. SPAM-3Q-HETCOR is then applied to generate 27Al–31P spectra of the devitrified 41Na2O–20.5Al2O3–38.5P2O5 glass and the silicoaluminophosphate ECR-40. Finally, the method allowed the acquisition of the first high resolution solid-state Correlation spectra between 27Al and 29Si.
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Chemical bonding differences evidenced from J-coupling in solid state NMR experiments involving quadrupolar nuclei
Journal of Magnetic Resonance, 2003Co-Authors: Dominique Massiot, Julien Trébosc, Franck Fayon, Bruno Alonso, Jean-paul AmoureuxAbstract:Small scalar J-coupling between quadrupolar nuclei and spin 1/2 can be measured in inorganic solids using J-Resolved experiments and further used to acquire 2D J-HQMC Heteronuclear Correlation, giving detailed insight into the chemical bonding scheme.