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Stief T, Vormann K, Lakomek NA. Sensitivity-enhanced NMR 15N R 1 and R 1ρ relaxation experiments for the investigation of intrinsically disordered proteins at high magnetic fields. Methods 2024; 223:1-15. [PMID: 38242384 DOI: 10.1016/j.ymeth.2024.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/21/2023] [Accepted: 01/16/2024] [Indexed: 01/21/2024] Open
Abstract
NMR relaxation experiments provide residue-specific insights into the structural dynamics of proteins. Here, we present an optimized set of sensitivity-enhanced 15N R1 and R1ρ relaxation experiments applicable to fully protonated proteins. The NMR pulse sequences are conceptually similar to the set of TROSY-based sequences and their HSQC counterpart (Lakomek et al., J. Biomol. NMR 2012). Instead of the TROSY read-out scheme, a sensitivity-enhanced HSQC read-out scheme is used, with improved and easier optimized water suppression. The presented pulse sequences are applied on the cytoplasmic domain of the SNARE protein Synpatobrevin-2 (Syb-2), which is intrinsically disordered in its monomeric pre-fusion state. A two-fold increase in the obtained signal-to-noise ratio is observed for this intrinsically disordered protein, therefore offering a four-fold reduction of measurement time compared to the TROSY-detected version. The inter-scan recovery delay can be shortened to two seconds. Pulse sequences were tested at 600 MHz and 1200 MHz 1H Larmor frequency, thus applicable over a wide magnetic field range. A comparison between protonated and deuterated protein samples reveals high agreement, indicating that reliable 15N R1 and R1ρ rate constants can be extracted for fully protonated and deuterated samples. The presented pulse sequences will benefit not only for IDPs but also for an entire range of low and medium-sized proteins.
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Affiliation(s)
- Tobias Stief
- Institute of Biological Information Processing (IBI-7), Forschungszentrum Jülich, Jülich, Germany; Institute of Physical Biology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Katharina Vormann
- Institute of Biological Information Processing (IBI-7), Forschungszentrum Jülich, Jülich, Germany; Institute of Physical Biology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Nils-Alexander Lakomek
- Institute of Biological Information Processing (IBI-7), Forschungszentrum Jülich, Jülich, Germany; Institute of Physical Biology, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
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2
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McKay RT. Metabolomics and NMR. Handb Exp Pharmacol 2023; 277:73-116. [PMID: 36355220 DOI: 10.1007/164_2022_616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this manuscript will be to convince the reader to dive deeper into NMR spectroscopy and prevent the technique from being just another "black-box" in the lab. We will try to concisely highlight interesting topics and supply additional references for further exploration at each stage. The advantages of delving into the technique will be shown. The secondary objective, i.e., avoiding common problems before starting, will hopefully then become clear. Lastly, we will emphasize the spectrometer information needed for manuscript reporting to allow reproduction of results and confirm findings.
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Affiliation(s)
- Ryan T McKay
- Department Chemistry, College of Natural and Applied Sciences, University of Alberta, Edmonton, AB, Canada.
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3
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Pelupessy P. Radiation damping strongly perturbs remote resonances in the presence of homonuclear mixing. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2022; 3:43-51. [PMID: 37905177 PMCID: PMC10539763 DOI: 10.5194/mr-3-43-2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/12/2022] [Indexed: 11/02/2023]
Abstract
In this work, it is experimentally shown that the weak oscillating magnetic field (known as the "radiation damping" field) caused by the inductive coupling between the transverse magnetization of nuclei and the radio frequency circuit perturbs remote resonances when homonuclear total correlation mixing is applied. Numerical simulations are used to rationalize this effect.
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Affiliation(s)
- Philippe Pelupessy
- Laboratoire des Biomolécules (LBM), Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
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4
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Herbert-Pucheta JE, Lozada-Ramírez JD, Ortega-Regules AE, Hernández LR, Anaya de Parrodi C. Nuclear Magnetic Resonance Metabolomics with Double Pulsed-Field-Gradient Echo and Automatized Solvent Suppression Spectroscopy for Multivariate Data Matrix Applied in Novel Wine and Juice Discriminant Analysis. Molecules 2021; 26:molecules26144146. [PMID: 34299421 PMCID: PMC8307358 DOI: 10.3390/molecules26144146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/21/2021] [Accepted: 06/23/2021] [Indexed: 12/03/2022] Open
Abstract
The quality of foods has led researchers to use various analytical methods to determine the amounts of principal food constituents; some of them are the NMR techniques with a multivariate statistical analysis (NMR-MSA). The present work introduces a set of NMR-MSA novelties. First, the use of a double pulsed-field-gradient echo (DPFGE) experiment with a refocusing band-selective uniform response pure-phase selective pulse for the selective excitation of a 5–10-ppm range of wine samples reveals novel broad 1H resonances. Second, an NMR-MSA foodomics approach to discriminate between wine samples produced from the same Cabernet Sauvignon variety fermented with different yeast strains proposed for large-scale alcohol reductions. Third a comparative study between a nonsupervised Principal Component Analysis (PCA), supervised standard partial (PLS-DA), and sparse (sPLS-DA) least squares discriminant analysis, as well as orthogonal projections to a latent structures discriminant analysis (OPLS-DA), for obtaining holistic fingerprints. The MSA discriminated between different Cabernet Sauvignon fermentation schemes and juice varieties (apple, apricot, and orange) or juice authentications (puree, nectar, concentrated, and commercial juice fruit drinks). The new pulse sequence DPFGE demonstrated an enhanced sensitivity in the aromatic zone of wine samples, allowing a better application of different unsupervised and supervised multivariate statistical analysis approaches.
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Affiliation(s)
- José Enrique Herbert-Pucheta
- Consejo Nacional de Ciencia y Tecnología-Laboratorio Nacional de Investigación y Servicio Agroalimentario y Forestal, Universidad Autónoma Chapingo, Carretera México-Texcoco km 38.5, Chapingo, Estado de México 56230, Mexico;
- Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala s/n, Colonia Santo Tomás, Ciudad de México 11340, Mexico
| | - José Daniel Lozada-Ramírez
- Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
| | - Ana E. Ortega-Regules
- Departamento de Ciencias de la Salud, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
| | - Luis Ricardo Hernández
- Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
- Correspondence: (L.R.H.); (C.A.d.P.); Tel.: +52-222-2292412 (L.R.H.); +52-222-2292005 (C.A.d.P.)
| | - Cecilia Anaya de Parrodi
- Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
- Correspondence: (L.R.H.); (C.A.d.P.); Tel.: +52-222-2292412 (L.R.H.); +52-222-2292005 (C.A.d.P.)
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5
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Kew W, Bell NG, Goodall I, Uhrín D. Advanced solvent signal suppression for the acquisition of 1D and 2D NMR spectra of Scotch Whisky. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:785-796. [PMID: 28558164 PMCID: PMC5599976 DOI: 10.1002/mrc.4621] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/24/2017] [Accepted: 05/26/2017] [Indexed: 06/07/2023]
Abstract
A simple and robust solvent suppression technique that enables acquisition of high-quality 1D 1 H nuclear magnetic resonance (NMR) spectra of alcoholic beverages on cryoprobe instruments was developed and applied to acquire NMR spectra of Scotch Whisky. The method uses 3 channels to suppress signals of water and ethanol, including those of 13 C satellites of ethanol. It is executed in automation allowing high throughput investigations of alcoholic beverages. On the basis of the well-established 1D nuclear Overhauser spectroscopy (NOESY) solvent suppression technique, this method suppresses the solvent at the beginning of the pulse sequence, producing pure phase signals minimally affected by the relaxation. The developed solvent suppression procedure was integrated into several homocorrelated and heterocorrelated 2D NMR experiments, including 2D correlation spectroscopy (COSY), 2D total correlation spectroscopy (TOCSY), 2D band-selective TOCSY, 2D J-resolved spectroscopy, 2D 1 H, 13 C heteronuclear single-quantum correlation spectroscopy (HSQC), 2D 1 H, 13 C HSQC-TOCSY, and 2D 1 H, 13 C heteronuclear multiple-bond correlation spectroscopy (HMBC). A 1D chemical-shift-selective TOCSY experiments was also modified. The wealth of information obtained by these experiments will assist in NMR structure elucidation of Scotch Whisky congeners and generally the composition of alcoholic beverages at the molecular level.
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Affiliation(s)
- Will Kew
- EastCHEM School of ChemistryUniversity of EdinburghKing's Buildings, David Brewster RoadEdinburghEH9 3FJUK
| | - Nicholle G.A. Bell
- EastCHEM School of ChemistryUniversity of EdinburghKing's Buildings, David Brewster RoadEdinburghEH9 3FJUK
| | - Ian Goodall
- The Scotch Whisky Research InstituteThe Robertson Trust Building, Research Avenue North, RiccartonEdinburghEH14 4APUK
| | - Dušan Uhrín
- EastCHEM School of ChemistryUniversity of EdinburghKing's Buildings, David Brewster RoadEdinburghEH9 3FJUK
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Bayle K, Julien M, Remaud GS, Akoka S. Suppression of radiation damping for high precision quantitative NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 259:121-125. [PMID: 26319280 DOI: 10.1016/j.jmr.2015.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 08/10/2015] [Accepted: 08/12/2015] [Indexed: 06/04/2023]
Abstract
True quantitative analysis of concentrated samples by (1)H NMR is made very difficult by Radiation Damping. A novel NMR sequence (inspired by the WET NMR sequence and by Outer Volume Saturation methods) is therefore proposed to suppress this phenomenon by reducing the spatial area and consequently the number of spins contributing to the signal detected. The size of the detected volume can be easily chosen in a large range and line shape distortions are avoided thanks to a uniform signal suppression of the outer volume. Composition of a mixture can as a result be determined with very high accuracy (precision and trueness) at the per mille level whatever the concentrations and without hardware modification.
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Affiliation(s)
- Kevin Bayle
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modeling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
| | - Maxime Julien
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modeling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
| | - Gérald S Remaud
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modeling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
| | - Serge Akoka
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modeling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France.
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7
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Ishima R. Effects of radiation damping for biomolecular NMR experiments in solution: a hemisphere concept for water suppression. CONCEPTS IN MAGNETIC RESONANCE. PART A, BRIDGING EDUCATION AND RESEARCH 2015; 44A:252-262. [PMID: 27524944 PMCID: PMC4980088 DOI: 10.1002/cmr.a.21360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Abundant solvent nuclear spins, such as water protons in aqueous solution, cause radiation damping in NMR experiments. It is important to know how the effect of radiation damping appears in high-resolution protein NMR because macromolecular studies always require very high magnetic field strengths with a highly sensitive NMR probe that can easily cause radiation damping. Here, we show the behavior of water magnetization after a pulsed-field gradient (PFG) using nutation experiments at 900 MHz with a cryogenic probe: when water magnetization is located in the upper hemisphere (having +Z component, parallel to the external magnetic field), dephasing of the magnetization by a PFG effectively suppresses residual water magnetization in the transverse plane. In contrast, when magnetization is located in the lower hemisphere (having -Z component), the small residual transverse component remaining after a PFG is still sufficient to induce radiation damping. Based on this observation, we designed 1H-15N HSQC experiments in which water magnetization is maintained in the upper hemisphere, but not necessarily along Z, and compared them with the conventional experiments, in which water magnetization is inverted during the t1 period. The result demonstrates moderate gain of signal-to-noise ratio, 0-28%. Designing the experiments such that water magnetization is maintained in the upper hemisphere allows shorter pulses to be used compared to the complete water flip-back and, thereby, is useful as a building block of protein NMR pulse programs in solution.
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Affiliation(s)
- Rieko Ishima
- Department of Structural Biology, School of Medicine, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15260
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8
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Gairí M, Dyachenko A, González MT, Feliz M, Pons M, Giralt E. An optimized method for (15)N R(1) relaxation rate measurements in non-deuterated proteins. JOURNAL OF BIOMOLECULAR NMR 2015; 62:209-20. [PMID: 25947359 PMCID: PMC4451471 DOI: 10.1007/s10858-015-9937-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 04/27/2015] [Indexed: 05/20/2023]
Abstract
(15)N longitudinal relaxation rates are extensively used for the characterization of protein dynamics; however, their accurate measurement is hindered by systematic errors. (15)N CSA/(1)H-(15)N dipolar cross-correlated relaxation (CC) and amide proton exchange saturation transfer from water protons are the two main sources of systematic errors in the determination of (15)N R1 rates through (1)H-(15)N HSQC-based experiments. CC is usually suppressed through a train of 180° proton pulses applied during the variable (15)N relaxation period (T), which can perturb water magnetization. Thus CC cancellation is required in such a way as to minimize water saturation effects. Here we examined the level of water saturation during the T period caused by various types of inversion proton pulses to suppress CC: (I) amide-selective IBURP-2; (II) cosine-modulated IBURP-2; (III) Watergate-like blocks; and (IV) non-selective hard. We additionally demonstrate the effect of uncontrolled saturation of aliphatic protons on (15)N R1 rates. In this paper we present an optimized pulse sequence that takes into account the crucial effect of controlling also the saturation of the aliphatic protons during (15)N R1 measurements in non-deuterated proteins. We show that using cosine-modulated IBURP-2 pulses spaced 40 ms to cancel CC in this optimized pulse program is the method of choice to minimize systematic errors coming from water and aliphatic protons saturation effects.
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Affiliation(s)
- Margarida Gairí
- />NMR Facility, Scientific and Technological Centers, University of Barcelona (CCiTUB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Andrey Dyachenko
- />Institute for Research in Biomedicine (IRB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - M. Teresa González
- />NMR Facility, Scientific and Technological Centers, University of Barcelona (CCiTUB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Miguel Feliz
- />NMR Facility, Scientific and Technological Centers, University of Barcelona (CCiTUB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Miquel Pons
- />Biomolecular NMR Laboratory and Organic Chemistry Department, University of Barcelona, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Ernest Giralt
- />Institute for Research in Biomedicine (IRB), Baldiri Reixac 10, 08028 Barcelona, Spain
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9
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Rennella E, Solyom Z, Brutscher B. Measuring hydrogen exchange in proteins by selective water saturation in (1)H- (15)N SOFAST/BEST-type experiments: advantages and limitations. JOURNAL OF BIOMOLECULAR NMR 2014; 60:99-107. [PMID: 25173410 DOI: 10.1007/s10858-014-9857-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 08/22/2014] [Indexed: 06/03/2023]
Abstract
HET(ex)-SOFAST NMR (Schanda et al. in J Biomol NMR 33:199-211, 2006) has been proposed some years ago as a fast and sensitive method for semi-quantitative measurement of site-specific amide-water hydrogen exchange effects along the backbone of proteins. Here we extend this concept to BEST readout sequences that provide a better resolution at the expense of some loss in sensitivity. We discuss the theoretical background and implementation of the experiment, and demonstrate its performance for an intrinsically disordered protein, 2 well folded globular proteins, and a transiently populated folding intermediate state. We also provide a critical evaluation of the level of accuracy that can be obtained when extracting quantitative exchange rates from HET(ex) NMR measurements.
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Affiliation(s)
- Enrico Rennella
- Institut de Biologie Structurale, Université Grenoble 1, 71 avenue des Martyrs, 38044, Grenoble Cedex 9, France
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10
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Lacy P, McKay RT, Finkel M, Karnovsky A, Woehler S, Lewis MJ, Chang D, Stringer KA. Signal intensities derived from different NMR probes and parameters contribute to variations in quantification of metabolites. PLoS One 2014; 9:e85732. [PMID: 24465670 PMCID: PMC3897511 DOI: 10.1371/journal.pone.0085732] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 12/02/2013] [Indexed: 12/29/2022] Open
Abstract
We discovered that serious issues could arise that may complicate interpretation of metabolomic data when identical samples are analyzed at more than one NMR facility, or using slightly different NMR parameters on the same instrument. This is important because cross-center validation metabolomics studies are essential for the reliable application of metabolomics to clinical biomarker discovery. To test the reproducibility of quantified metabolite data at multiple sites, technical replicates of urine samples were assayed by 1D-1H-NMR at the University of Alberta and the University of Michigan. Urine samples were obtained from healthy controls under a standard operating procedure for collection and processing. Subsequent analysis using standard statistical techniques revealed that quantitative data across sites can be achieved, but also that previously unrecognized NMR parameter differences can dramatically and widely perturb results. We present here a confirmed validation of NMR analysis at two sites, and report the range and magnitude that common NMR parameters involved in solvent suppression can have on quantitated metabolomics data. Specifically, saturation power levels greatly influenced peak height intensities in a frequency-dependent manner for a number of metabolites, which markedly impacted the quantification of metabolites. We also investigated other NMR parameters to determine their effects on further quantitative accuracy and precision. Collectively, these findings highlight the importance of and need for consistent use of NMR parameter settings within and across centers in order to generate reliable, reproducible quantified NMR metabolomics data.
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Affiliation(s)
- Paige Lacy
- Pulmonary Research Group, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | | | - Michael Finkel
- Department of Clinical, Social and Administrative Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Alla Karnovsky
- Department of Computational Medicine and Bioinformatics, School of Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Scott Woehler
- Department of Medicinal Chemistry and the Biochemical Nuclear Magnetic Resonance Core, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, United States of America
| | | | | | - Kathleen A. Stringer
- Department of Clinical, Social and Administrative Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Computational Medicine and Bioinformatics, School of Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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11
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Sun P, Jiang X, Jiang B, Zhang X, Liu M. Biomolecular ligands screening using radiation damping difference WaterLOGSY spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2013; 56:285-290. [PMID: 23740293 DOI: 10.1007/s10858-013-9748-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 05/28/2013] [Indexed: 06/02/2023]
Abstract
Water-ligand observed via gradient spectroscopy (WaterLOGSY) is a widely used nuclear magnetic resonance method for ligand screening. The crucial procedure for the effectiveness of WaterLOGSY is selective excitation of the water resonance. The selective excitation is conventionally achieved by using long selective pulse, which causes partial saturation of the water magnetization leading to reduction of sensitivity, in addition to time consuming and error prone. Therefore, many improvements have been made to enhance the sensitivity and robustness of the method. Here we propose an alternative selective excitation scheme for WaterLOGSY by utilizing radiation damping effect. The pulse scheme starts simply with a hard inversion pulse, instead of selective pulse or pulse train, followed by a pulse field gradient to control the radiation damping effect. The rest parts of the pulse scheme are similar to conventional WaterLOGSY. When the gradient pulse is applied immediately after the inversion pulse, the radiation damping effect is suppressed, and all of the magnetization is inversed. When the gradient pulse and the inversion pulse are about 10-20 ms apart, the radiation damping effect remains active and drives the water magnetization toward +z-axis, resulting in selective non-inversion of the water magnetization. By taking the differences of the spectra obtained under these two conditions, one should get the result of WaterLOGSY. The method is demonstrated to be simple, robust and sensitive for ligand screening.
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Affiliation(s)
- Peng Sun
- Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
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12
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Desvaux H. Non-linear liquid-state NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 70:50-71. [PMID: 23540576 DOI: 10.1016/j.pnmrs.2012.11.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 10/31/2012] [Indexed: 06/02/2023]
Affiliation(s)
- Hervé Desvaux
- CEA, IRAMIS, SIS2M, UMR CEA/CNRS 3299, Laboratoire Structure et Dynamique par Résonance Magnétique, CEA/Saclay, Gif-sur-Yvette, France.
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13
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Krishnan VV, Murali N. Radiation damping in modern NMR experiments: progress and challenges. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 68:41-57. [PMID: 23398972 PMCID: PMC3644564 DOI: 10.1016/j.pnmrs.2012.06.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 06/07/2012] [Indexed: 05/12/2023]
Affiliation(s)
- V V Krishnan
- Department of Chemistry, California State University, Fresno, CA 93740, USA.
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