Progress in Nuclear Magnetic Resonance Spectroscopy最新文献_第7页

Relaxivity of manganese ferrite nanoparticles 铁酸锰纳米颗粒的弛豫率

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-10-01 DOI: 10.1016/j.pnmrs.2020.07.002

Joop A. Peters

引用次数: 15

NMR-based isotopic and isotopomic analysis 基于核磁共振的同位素和同位素分析

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-10-01 DOI: 10.1016/j.pnmrs.2020.07.001

Serge Akoka, Gérald S. Remaud

{"title":"NMR-based isotopic and isotopomic analysis","authors":"Serge Akoka, Gérald S. Remaud","doi":"10.1016/j.pnmrs.2020.07.001","DOIUrl":"10.1016/j.pnmrs.2020.07.001","url":null,"abstract":"<div><p>Molecules exist in different isotopic compositions and most of the processes, physical or chemical, in living systems cause selection between heavy and light isotopes. Thus, knowing the isotopic fractionation of the common atoms, such as H, C, N, O or S, at each step during a metabolic pathway allows the construction of a unique isotope profile that reflects its past history. Having access to the isotope abundance gives valuable clues about the (bio)chemical origin of biological or synthetic molecules. Whereas the isotope ratio measured by mass spectrometry provides a global isotope composition, quantitative NMR measures isotope ratios at individual positions within a molecule. We present here the requirements and the corresponding experimental strategies to use quantitative NMR for measuring intramolecular isotope profiles. After an introduction showing the historical evolution of NMR for measuring isotope ratios, the vocabulary and symbols – for describing the isotope content and quantifying its change – are defined. Then, the theoretical framework of very accurate quantitative NMR is presented as the principle of Isotope Ratio Measurement by NMR spectroscopy, including the practical aspects with nuclei other than <sup>2</sup>H, that have been developed and employed to date. Lastly, the most relevant applications covering three issues, tackling counterfeiting, authentication, and forensic investigation, are presented, before giving some perspectives combining technical improvements and methodological approaches.</p></div>","PeriodicalId":20740,"journal":{"name":"Progress in Nuclear Magnetic Resonance Spectroscopy","volume":"120 ","pages":"Pages 1-24"},"PeriodicalIF":6.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.pnmrs.2020.07.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38610277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21

Manipulating beams of paramagnetic atoms and molecules using inhomogeneous magnetic fields 利用不均匀磁场操纵顺磁性原子和分子束

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-10-01 DOI: 10.1016/j.pnmrs.2020.08.002

Paul Jansen, Frédéric Merkt

引用次数: 7

Pulse sequences for measuring exchange rates between proton species: From unlocalised NMR spectroscopy to chemical exchange saturation transfer imaging 用于测量质子之间交换速率的脉冲序列:从非局部核磁共振波谱到化学交换饱和转移成像

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-10-01 DOI: 10.1016/j.pnmrs.2020.06.001

Eleni Demetriou, Aaron Kujawa, Xavier Golay

{"title":"Pulse sequences for measuring exchange rates between proton species: From unlocalised NMR spectroscopy to chemical exchange saturation transfer imaging","authors":"Eleni Demetriou, Aaron Kujawa, Xavier Golay","doi":"10.1016/j.pnmrs.2020.06.001","DOIUrl":"10.1016/j.pnmrs.2020.06.001","url":null,"abstract":"<div><p>Within the field of NMR spectroscopy, the study of chemical exchange processes through saturation transfer techniques has a long history. In the context of MRI, chemical exchange techniques have been adapted to increase the sensitivity of imaging to small fractions of exchangeable protons, including the labile protons of amines, amides and hydroxyls. The MR contrast is generated by frequency-selective irradiation of the labile protons, which results in a reduction of the water signal associated with transfer of the labile protons’ saturated magnetization to the protons of the surrounding free water. The signal intensity depends on the rate of chemical exchange and the concentration of labile protons as well as on the properties of the irradiation field. This methodology is referred to as CEST (chemical exchange saturation transfer) imaging. Applications of CEST include imaging of molecules with short transverse relaxation times and mapping of physiological parameters such as pH, temperature, buffer concentration and chemical composition due to the dependency of this chemical exchange effect on all these parameters. This article aims to describe these effects both theoretically and experimentally. In depth analysis and mathematical modelling are provided for all pulse sequences designed to date to measure the chemical exchange rate. Importantly, it has become clear that the background signal from semi-solid protons and the presence of the Nuclear Overhauser Effect (NOE), either through direct dipole-dipole mechanisms or through exchange-relayed signals, complicates the analysis of CEST effects. Therefore, advanced methods to suppress these confounding factors have been developed, and these are also reviewed. Finally, the experimental work conducted both <em>in vitro</em> and <em>in vivo</em> is discussed and the progress of CEST imaging towards clinical practice is presented.</p></div>","PeriodicalId":20740,"journal":{"name":"Progress in Nuclear Magnetic Resonance Spectroscopy","volume":"120 ","pages":"Pages 25-71"},"PeriodicalIF":6.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.pnmrs.2020.06.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38610282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Contemporary approaches to high-field magnetic resonance imaging with large field inhomogeneity 大场非均匀性高场磁共振成像的当代方法

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-10-01 DOI: 10.1016/j.pnmrs.2020.07.003

Michael Mullen, Michael Garwood

{"title":"Contemporary approaches to high-field magnetic resonance imaging with large field inhomogeneity","authors":"Michael Mullen, Michael Garwood","doi":"10.1016/j.pnmrs.2020.07.003","DOIUrl":"10.1016/j.pnmrs.2020.07.003","url":null,"abstract":"<div><p>Despite its importance as a clinical imaging modality, magnetic resonance imaging remains inaccessible to most of the world’s population due to its high cost and infrastructure requirements. Substantial effort is underway to develop portable, low-cost systems able to address MRI access inequality and to enable new uses of MRI such as bedside imaging. A key barrier to development of portable MRI systems is increased magnetic field inhomogeneity when using small polarizing magnets, which degrades image quality through distortions and signal dropout. Many approaches address field inhomogeneity by using a low polarizing field, approximately ten to hundreds of milli-Tesla. At low-field, even a large relative field inhomogeneity of several thousand parts-per-million (ppm) results in resonance frequency dispersion of only 1–2 kHz. Under these conditions, with necessarily wide pulse bandwidths, fast spin-echo sequences may be used at low field with negligible subject heating, and a broad range of other available imaging sequences can be implemented. However, high-field MRI, 1.5 T or greater, can provide substantially improved signal-to-noise ratio and image contrast, so that higher spatial resolution, clinical quality images may be acquired in significantly less time than is necessary at low-field. The challenge posed by small, high-field systems is that the relative field inhomogeneity, still thousands of ppm, becomes tens of kilohertz over the imaging volume. This article describes the physical consequences of field inhomogeneity on established gradient- and spin-echo MRI sequences, and suggests ways to reduce signal dropout and image distortion from field inhomogeneity. Finally, the practicality of currently available image contrasts is reviewed when imaging with a high magnetic field with large inhomogeneity.</p></div>","PeriodicalId":20740,"journal":{"name":"Progress in Nuclear Magnetic Resonance Spectroscopy","volume":"120 ","pages":"Pages 95-108"},"PeriodicalIF":6.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.pnmrs.2020.07.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38610286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Automated assignment of methyl NMR spectra from large proteins 大蛋白质甲基核磁共振谱的自动分配

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-06-01 DOI: 10.1016/j.pnmrs.2020.04.001

Iva Pritišanac , T. Reid Alderson , Peter Güntert

{"title":"Automated assignment of methyl NMR spectra from large proteins","authors":"Iva Pritišanac , T. Reid Alderson , Peter Güntert","doi":"10.1016/j.pnmrs.2020.04.001","DOIUrl":"10.1016/j.pnmrs.2020.04.001","url":null,"abstract":"<div><p>As structural biology trends towards larger and more complex biomolecular targets, a detailed understanding of their interactions and underlying structures and dynamics is required. The development of methyl-TROSY has enabled NMR spectroscopy to provide atomic-resolution insight into the mechanisms of large molecular assemblies in solution. However, the applicability of methyl-TROSY has been hindered by the laborious and time-consuming resonance assignment process, typically performed with domain fragmentation, site-directed mutagenesis, and analysis of NOE data in the context of a crystal structure. In response, several structure-based automatic methyl assignment strategies have been developed over the past decade. Here, we present a comprehensive analysis of all available methods and compare their input data requirements, algorithmic strategies, and reported performance. In general, the methods fall into two categories: those that primarily rely on inter-methyl NOEs, and those that utilize methyl PRE- and PCS-based restraints. We discuss their advantages and limitations, and highlight the potential benefits from standardizing and combining different methods.</p></div>","PeriodicalId":20740,"journal":{"name":"Progress in Nuclear Magnetic Resonance Spectroscopy","volume":"118 ","pages":"Pages 54-73"},"PeriodicalIF":6.1,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.pnmrs.2020.04.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38342290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Use of dissolved hyperpolarized species in NMR: Practical considerations 在核磁共振中使用溶解的超极化物质:实际考虑

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-06-01 DOI: 10.1016/j.pnmrs.2020.03.002

Patrick Berthault , Céline Boutin , Charlotte Martineau-Corcos , Guillaume Carret

{"title":"Use of dissolved hyperpolarized species in NMR: Practical considerations","authors":"Patrick Berthault , Céline Boutin , Charlotte Martineau-Corcos , Guillaume Carret","doi":"10.1016/j.pnmrs.2020.03.002","DOIUrl":"10.1016/j.pnmrs.2020.03.002","url":null,"abstract":"<div><p><span><span>Hyperpolarization techniques that can transiently boost nuclear spin polarization<span> are generally carried out at low temperature – as in the case of dynamic nuclear polarization – or at high temperature in the </span></span>gaseous state<span><span> – as in the case of optically pumped noble gases. This review aims at describing the various issues and challenges that have been encountered during dissolution of hyperpolarized species, and solutions to these problems that have been or are currently proposed in the literature. During the transport of molecules from the </span>polarizer to the NMR detection region, and when the hyperpolarized species or a precursor of hyperpolarization (</span></span><em>e.g.</em><span> parahydrogen) is introduced into the solution of interest, several obstacles need to be overcome to keep a high level of final magnetization. The choice of the magnetic field, the design of the dissolution setup, and ways to isolate hyperpolarized compounds from relaxation agents will be presented. Due to the non-equilibrium character of the hyperpolarization, new NMR pulse sequences that perform better than the classical ones will be described. Finally, three applications in the field of biology will be briefly mentioned.</span></p></div>","PeriodicalId":20740,"journal":{"name":"Progress in Nuclear Magnetic Resonance Spectroscopy","volume":"118 ","pages":"Pages 74-90"},"PeriodicalIF":6.1,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.pnmrs.2020.03.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38342293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

NMR crystallography of molecular organics 分子有机物的核磁共振晶体学

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-06-01 DOI: 10.1016/j.pnmrs.2020.03.001

Paul Hodgkinson

引用次数: 71

Recent developments in the use of fluorine NMR in synthesis and characterisation 氟核磁共振在合成和表征方面的最新进展

IF 6.1 2区化学

Progress in Nuclear Magnetic Resonance Spectroscopy Pub Date : 2020-06-01 DOI: 10.1016/j.pnmrs.2020.02.002

Peter W.A. Howe

引用次数: 9

The interpretation of small molecule diffusion coefficients: Quantitative use of diffusion-ordered NMR spectroscopy 小分子扩散系数的解释:扩散有序核磁共振光谱的定量使用