NMR spectroscopy

NMR 光谱学
  • 文章类型: Journal Article
    低场核磁共振(NMR)有三种通用模式:光谱学,成像,和弛豫测量。在过去的12年里,光谱学的模态,也被称为台式核磁共振,紧凑型核磁共振,或者只是低场核磁共振,由于新的永磁材料和设计,已经经历了仪器的发展。因此,台式NMR已成为用于过程分析控制(PAC)的强大分析工具。然而,NMR设备作为分析工具在多个领域的成功应用与它与不同化学计量学方法的耦合有着内在的联系。这篇综述集中在化学分析中的台式NMR和化学计量学的演变,包括在燃料中的应用,食物,制药,生物化学,毒品,代谢组学,和聚合物。该综述还介绍了用于光谱采集的不同低分辨率NMR方法和用于校准的化学计量学技术,分类,歧视,数据融合,校准转移,多块和多路。
    Low-field nuclear magnetic resonance (NMR) has three general modalities: spectroscopy, imaging, and relaxometry. In the last twelve years, the modality of spectroscopy, also known as benchtop NMR, compact NMR, or just low-field NMR, has undergone instrumental development due to new permanent magnetic materials and design. As a result, benchtop NMR has emerged as a powerful analytical tool for use in process analytical control (PAC). Nevertheless, the successful application of NMR devices as an analytical tool in several areas is intrinsically linked to its coupling with different chemometric methods. This review focuses on the evolution of benchtop NMR and chemometrics in chemical analysis, including applications in fuels, foods, pharmaceuticals, biochemicals, drugs, metabolomics, and polymers. The review also presents different low-resolution NMR methods for spectrum acquisition and chemometric techniques for calibration, classification, discrimination, data fusion, calibration transfer, multi-block and multi-way.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    脂质分析是食品认证和质量控制的一个组成部分,它为消费者提供了必要的信息,以便对他们的脂质摄入量做出明智的决定。脂质分析和脂质组范围的最新进展代表了食品科学的巨大机遇。在这篇综述中,我们全面概述了可用的提取工具,分析和解释与膳食脂肪分析相关的数据。讨论了不同的分析平台,包括GC,MS,NMR,IR和UV强调其优点和局限性,以及化学计量模型和脂质靶向在线数据库等补充工具。这里介绍的应用包括质量控制,有机和美味食品的认证,追踪膳食脂肪来源,并研究热量/储存对脂质的影响。多种具有不同灵敏度的分析方法,负担能力,再现性和易于操作现在可用于全面分析膳食脂肪。这些方法的应用范围包括有利于使用基于MS的方法等大数据生成平台的研究,常规质量控制,要求易于使用负担得起的设备,如TLC和IR。因此,这篇综述为食品科学家提供了一个导航工具,以帮助他们为未来的脂质分析探索开发一个最佳方案。
    Lipid analysis is an integral part of food authentication and quality control which provides consumers with the necessary information to make an informed decision about their lipid intake. Recent advancement in lipid analysis and lipidome scope represents great opportunities for food science. In this review we provide a comprehensive overview of available tools for extraction, analysis and interpretation of data related to dietary fats analyses. Different analytical platforms are discussed including GC, MS, NMR, IR and UV with emphasis on their merits and limitations alongside complementary tools such as chemometric models and lipid-targeted online databases. Applications presented here include quality control, authentication of organic and delicacy food, tracing dietary fat source and investigating the effect of heat/storage on lipids. A multitude of analytical methods with different sensitivity, affordability, reproducibility and ease of operation are now available to comprehensively analyze dietary fats. Application of these methods range from studies which favor the use of large data generating platforms such as MS-based methods, to routine quality control which demands easy to use affordable equipment as TLC and IR. Hence, this review provides a navigation tool for food scientists to help develop an optimal protocol for their future lipid analysis quest.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    核磁共振(NMR)光谱是代谢组学的主要分析技术之一。它具有样品制备最少和重现性高的优点,使其成为为生物库和大规模研究产生大量代谢组学数据的理想技术。代谢组学是一种流行的“组学”技术,已经确立了自己作为一个全面的探索性生物标志物工具;然而,由于在小规模研究中缺乏代谢组学工作流程的标准化,因此它尚未在数据整理方面发挥其协作潜力。这篇系统综述汇编了用于血清的不同NMR代谢组学方法,等离子体,和尿液研究,从样本收集到数据分析,在2019年和2020年的两年时间里,就业最普遍。它还概述了这些方法如何影响原始数据和下游解释,以及报告可重复性和结果验证的重要性。这篇评论可以作为NMR代谢组学工作流程的有价值的总结,这些工作流程被积极用于人类生物流体研究,并将有助于指导未来研究的工作流程选择。
    Nuclear magnetic resonance (NMR) spectroscopy is one of the principal analytical techniques for metabolomics. It has the advantages of minimal sample preparation and high reproducibility, making it an ideal technique for generating large amounts of metabolomics data for biobanks and large-scale studies. Metabolomics is a popular \"omics\" technology and has established itself as a comprehensive exploratory biomarker tool; however, it has yet to reach its collaborative potential in data collation due to the lack of standardisation of the metabolomics workflow seen across small-scale studies. This systematic review compiles the different NMR metabolomics methods used for serum, plasma, and urine studies, from sample collection to data analysis, that were most popularly employed over a two-year period in 2019 and 2020. It also outlines how these methods influence the raw data and the downstream interpretations, and the importance of reporting for reproducibility and result validation. This review can act as a valuable summary of NMR metabolomic workflows that are actively used in human biofluid research and will help guide the workflow choice for future research.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    SARS-CoV-2是导致正在进行的大流行的冠状病毒,感染人数超过460万,死亡人数超过600万。SARS-CoV-2核衣壳(N)是唯一的结构蛋白,在病毒生命周期的几乎所有关键步骤中起着重要作用,其功能取决于与各种核酸相互作用驱动的液-液相分离(LLPS)。419残基N蛋白在所有变体中都是高度保守的,包括delta和omicron,由折叠的N/C末端结构域(NTD/CTD)以及三个长的固有无序区域(IDR)组成。最近的结果表明其CTD和IDR也是隐蔽的核酸结合结构域。在这种情况下,预期能够干扰其与核酸相互作用的任何小分子调节其LLPS和相关功能。的确,ATP,在所有活细胞中存在非常高浓度(2-12mM)但在病毒中不存在的能量货币,调节N蛋白的LLPS,因此似乎在进化上被SARS-CoV-2劫持以促进其生命周期。羟氯喹(HCQ)也被证明特异性结合NTD和CTD,以抑制它们与核酸的相互作用。以及破坏LLPS。特别是,HCQ-CTD复合物的独特结构为进一步设计具有更好亲和力和特异性的抗SARS-CoV-2药物提供了有希望的策略.这一发现可能表明LLPS确实可以通过小分子制成药物,从而通过通常靶向LLPS为药物发现/设计开辟了有希望的方向。
    SARS-CoV-2 is the coronavirus causing the ongoing pandemic with > 460 millions of infections and > 6 millions of deaths. SARS-CoV-2 nucleocapsid (N) is the only structural protein which plays essential roles in almost all key steps of the viral life cycle with its diverse functions depending on liquid-liquid phase separation (LLPS) driven by interacting with various nucleic acids. The 419-residue N protein is highly conserved in all variants including delta and omicron, and composed of both folded N-/C-terminal domains (NTD/CTD) as well as three long intrinsically disordered regions (IDRs). Recent results have suggested that its CTD and IDRs are also cryptic nucleic acid-binding domains. In this context, any small molecules capable of interfering in its interaction with nucleic acids are anticipated to modulate its LLPS and associated functions. Indeed, ATP, the energy currency existing at very high concentrations (2-12 mM) in all living cells but absent in viruses, modulates LLPS of N protein, and consequently appears to be evolutionarily hijacked by SARS-CoV-2 to promote its life cycle. Hydroxychloroquine (HCQ) has been also shown to specifically bind NTD and CTD to inhibit their interactions with nucleic acids, as well as to disrupt LLPS. Particularly, the unique structure of the HCQ-CTD complex offers a promising strategy for further design of anti-SARS-CoV-2 drugs with better affinity and specificity. The finding may indicate that LLPS is indeed druggable by small molecules, thus opening up a promising direction for drug discovery/design by targeting LLPS in general.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    Nuclear magnetic resonance (NMR) spectroscopy is a robust method, which can rapidly analyze mixtures at the molecular level without requiring separation and/or purification steps, making it ideal for applications in food science. Despite its increasing popularity among food scientists, NMR is still an underutilized methodology in this area, mainly due to its high cost, relatively low sensitivity, and the lack of NMR expertise by many food scientists. The aim of this review is to help bridge the knowledge gap that may exist when attempting to apply NMR methodologies to the field of food science. We begin by covering the basic principles required to apply NMR to the study of foods and nutrients. A description of the discipline of chemometrics is provided, as the combination of NMR with multivariate statistical analysis is a powerful approach for addressing modern challenges in food science. Furthermore, a comprehensive overview of recent and key applications in the areas of compositional analysis, food authentication, quality control, and human nutrition is provided. In addition to standard NMR techniques, more sophisticated NMR applications are also presented, although limitations, gaps, and potentials are discussed. We hope this review will help scientists gain some of the knowledge required to apply the powerful methodology of NMR to the rich and diverse field of food science.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    核磁共振(NMR)光谱是化学中重要的分析工具,生物学和生命科学,但是它具有相对较低的灵敏度和较长的采集时间。因此,提高表观信噪比和加速数据采集变得不可或缺。在这次审查中,我们总结了低秩Hankel矩阵和张量方法的最新进展,利用自由感应衰减信号的指数特性,以实现有效的去噪和光谱重建。我们还概述了未来的发展,这些发展可能使NMR光谱成为一种更强大的技术。
    Nuclear magnetic resonance (NMR) spectroscopy is an important analytical tool in chemistry, biology, and life science, but it suffers from relatively low sensitivity and long acquisition time. Thus, improving the apparent signal-to-noise ratio and accelerating data acquisition became indispensable. In this review, we summarize the recent progress on low-rank Hankel matrix and tensor methods, which exploit the exponential property of free-induction decay signals, to enable effective denoising and spectra reconstruction. We also outline future developments that are likely to make NMR spectroscopy a far more powerful technique.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    Metabolomics involvement in the study of foods is steadily growing. Such a rise is a consequence of the increasing demand in the food sector to address challenges regarding the issues of food safety, quality, and authenticity in a more comprehensive way. Virgin olive oil (VOO) is a key product of the Mediterranean diet, with a globalized consumer interest as it may be associated with various nutritional and health benefits. Despite the strict legislation to protect this high added-value agricultural commodity and offer guarantees to consumers and honest producers, there are still analytical issues needing to be further addressed. Thus, this review aims to present the efforts made using targeted and untargeted metabolomics approaches, namely nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry-based techniques (mainly LC/GC-MS) combined with multivariate statistical analysis. Case-studies focusing on geographical/varietal classification and detection of adulteration are discussed with regards to the identification of possible markers. The advantages and limitations of each of the aforementioned techniques applied to VOO analysis are also highlighted.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    Since the concept of deep learning (DL) was formally proposed in 2006, it has had a major impact on academic research and industry. Nowadays, DL provides an unprecedented way to analyze and process data with demonstrated great results in computer vision, medical imaging, natural language processing, and so forth. Herein, applications of DL in NMR spectroscopy are summarized, and a perspective for DL as an entirely new approach that is likely to transform NMR spectroscopy into a much more efficient and powerful technique in chemistry and life sciences is outlined.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    Unravelling the relationship between food and health requires a more in-depth knowledge of the various changes occurring in the gastrointestinal tract during digestion and which may ultimately affect the nutritional quality and safety of ingested food lipids before absorption into the bloodstream. In this context, this review deals with the oxidation process of food lipids under digestive conditions and the studies carried out on this topic using different digestion models: in vitro, in vivo or ex vivo, static or dynamic, and including one, two and/or three digestive phases (oral, gastric and duodenal). These studies have contributed to clarifying the occurrence and extent of lipid degradation under such a particular environment, many of them also highlighting the factors affecting the advance or delay of the oxidation of dietary lipids during digestion, like: food lipid content, unsaturation degree and initial oxidative status; the presence in the food bolus of compounds showing antioxidant activity (polyphenols, tocopherols…) either added or naturally present; the presence in the food bolus of proteins (including iron or not); food technological or culinary processings (salting, smoking, cooking…), among others. Likewise, the methodologies employed to study lipid oxidation under digestive conditions are also summarized and future research perspectives are discussed.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

  • 文章类型: Journal Article
    Fatty acids are important nutritional substances and metabolites in living organisms. These acids are abundant in Chinese herbs, such as Brucea javanica, Notopterygium forbesii, Isatis tinctoria, Astragalus membranaceus, and Aconitum szechenyianum. This review illustrates the types of fatty acids and their significant roles in the human body. Many analytical methods are used for the qualitative and quantitative evaluation of fatty acids. Some of the methods used to analyze fatty acids in more than 30 kinds of plants, drugs, and other samples are presented in this paper. These analytical methods include gas chromatography, liquid chromatography, near-infrared spectroscopy, and NMR spectroscopy. The advantages and disadvantages of these techniques are described and compared. This review provides a valuable reference for establishing methods for fatty acid determination.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

公众号