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Dracínský M, Pohl R. Determination of the Nucleic Acid Adducts Structure at the Nucleoside/Nucleotide Level by NMR Spectroscopy. Chem Res Toxicol 2016; 28:155-65. [PMID: 25584790 DOI: 10.1021/tx5004535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
All living organisms are exposed to xenobiotics from the environment. The exposure can lead to the formation of covalent adducts of xenobiotics or their metabolites with nucleic acids (NAs).The knowledge of NA adduct structure provides valuable information n the mechanism of carcinogenesis on a molecular level. While NMR spectroscopy is extremely successful in structural analysis of many classes of molecules ranging from small inorganic and organic molecules to large biomacromolecules, the structural analysis of NA adducts by NMR spectroscopy is accompanied by some challenges. First, the structural diversity of the adducts is very large; the electrophilic species generated from the metabolism of xenobiotics can attack various atoms of the nucleobases, and new rings are frequently formed. The second challenge in the DNA adducts structure determination is the low sensitivity of NMR spectroscopy and low amount of the adducts isolated from in vivo experiments. Recent developments of NMR hardware and experimental methods have led, however, to unprecedented sensitivity. This contribution reviews NMR techniques that are commonly applied in the determination of nucleic acid adducts structure at the nucleoside/nucleotide level. These NMR techniques and the large structural heterogeneity of NA adducts are demonstrated on recent examples (mostly published after 2000) of NA adducts structure determined by NMR. Most of the examples report 2′-deoxyribonucles(t)ide derivatives, but RNA adducts are also briefly discussed. The influence of the formation of NA adducts on nucleoside conformation (particularly syn/anti orientation of the base) is also demonstrated on recent examples.
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105
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Ananikov VP, Galkin KI, Egorov MP, Sakharov AM, Zlotin SG, Redina EA, Isaeva VI, Kustov LM, Gening ML, Nifantiev NE. Challenges in the development of organic and hybrid molecular systems. MENDELEEV COMMUNICATIONS 2016. [DOI: 10.1016/j.mencom.2016.09.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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106
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Kovtunov KV, Salnikov OG, Zhivonitko VV, Skovpin IV, Bukhtiyarov VI, Koptyug IV. Catalysis and Nuclear Magnetic Resonance Signal Enhancement with Parahydrogen. Top Catal 2016. [DOI: 10.1007/s11244-016-0688-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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107
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van Duynhoven JPM, Jacobs DM. Assessment of dietary exposure and effect in humans: The role of NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 96:58-72. [PMID: 27573181 DOI: 10.1016/j.pnmrs.2016.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 03/19/2016] [Accepted: 03/19/2016] [Indexed: 06/06/2023]
Abstract
In human nutritional science progress has always depended strongly on analytical measurements for establishing relationships between diet and health. This field has undergone significant changes as a result of the development of NMR and mass spectrometry methods for large scale detection, identification and quantification of metabolites in body fluids. This has allowed systematic studies of the metabolic fingerprints that biological processes leave behind, and has become the research field of metabolomics. As a metabolic profiling technique, NMR is at its best when its unbiased nature, linearity and reproducibility are exploited in well-controlled nutritional intervention and cross-sectional population screening studies. Although its sensitivity is less good than that of mass spectrometry, NMR has maintained a strong position in metabolomics through implementation of standardisation protocols, hyphenation with mass spectrometry and chromatographic techniques, accurate quantification and spectral deconvolution approaches, and high-throughput automation. Thus, NMR-based metabolomics has contributed uniquely to new insights into dietary exposure, in particular by unravelling the metabolic fates of phytochemicals and the discovery of dietary intake markers. NMR profiling has also contributed to the understanding of the subtle effects of diet on central metabolism and lipoprotein metabolism. In order to hold its ground in nutritional metabolomics, NMR will need to step up its performance in sensitivity and resolution; the most promising routes forward are the analytical use of dynamic nuclear polarisation and developments in microcoil construction and automated fractionation.
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Affiliation(s)
- John P M van Duynhoven
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, 3130AC Vlaardingen, The Netherlands; Laboratory of Biophysics and Wageningen NMR Centre, Wageningen University, Dreijenlaan 3, 6703HA Wageningen, The Netherlands.
| | - Doris M Jacobs
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, 3130AC Vlaardingen, The Netherlands
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108
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A Multidisciplinary Approach to High Throughput Nuclear Magnetic Resonance Spectroscopy. SENSORS 2016; 16:s16060850. [PMID: 27294925 PMCID: PMC4934276 DOI: 10.3390/s16060850] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 05/30/2016] [Accepted: 06/02/2016] [Indexed: 02/03/2023]
Abstract
Nuclear Magnetic Resonance (NMR) is a non-contact, powerful structure-elucidation technique for biochemical analysis. NMR spectroscopy is used extensively in a variety of life science applications including drug discovery. However, existing NMR technology is limited in that it cannot run a large number of experiments simultaneously in one unit. Recent advances in micro-fabrication technologies have attracted the attention of researchers to overcome these limitations and significantly accelerate the drug discovery process by developing the next generation of high-throughput NMR spectrometers using Complementary Metal Oxide Semiconductor (CMOS). In this paper, we examine this paradigm shift and explore new design strategies for the development of the next generation of high-throughput NMR spectrometers using CMOS technology. A CMOS NMR system consists of an array of high sensitivity micro-coils integrated with interfacing radio-frequency circuits on the same chip. Herein, we first discuss the key challenges and recent advances in the field of CMOS NMR technology, and then a new design strategy is put forward for the design and implementation of highly sensitive and high-throughput CMOS NMR spectrometers. We thereafter discuss the functionality and applicability of the proposed techniques by demonstrating the results. For microelectronic researchers starting to work in the field of CMOS NMR technology, this paper serves as a tutorial with comprehensive review of state-of-the-art technologies and their performance levels. Based on these levels, the CMOS NMR approach offers unique advantages for high resolution, time-sensitive and high-throughput bimolecular analysis required in a variety of life science applications including drug discovery.
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109
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Misawa T, Wei F, Kikuchi J. Application of Two-Dimensional Nuclear Magnetic Resonance for Signal Enhancement by Spectral Integration Using a Large Data Set of Metabolic Mixtures. Anal Chem 2016; 88:6130-4. [DOI: 10.1021/acs.analchem.6b01495] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Takuma Misawa
- Graduate
School of Medical Life Science, Yokohama City University, 1-7-29
Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku,
Yokohama, Kanagawa 230-0045, Japan
| | - Feifei Wei
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku,
Yokohama, Kanagawa 230-0045, Japan
| | - Jun Kikuchi
- Graduate
School of Medical Life Science, Yokohama City University, 1-7-29
Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku,
Yokohama, Kanagawa 230-0045, Japan
- Graduate
School of Bioagricultural Sciences, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya, Aichi 464-0810, Japan
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110
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Vogel MW, Giorni A, Vegh V, Pellicer-Guridi R, Reutens DC. Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study. PLoS One 2016; 11:e0157040. [PMID: 27271886 PMCID: PMC4894570 DOI: 10.1371/journal.pone.0157040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 05/24/2016] [Indexed: 11/19/2022] Open
Abstract
OBJECT We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. MATERIALS AND METHODS The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. RESULTS A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. CONCLUSIONS A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.
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Affiliation(s)
- Michael W. Vogel
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Andrea Giorni
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Viktor Vegh
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Ruben Pellicer-Guridi
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - David C. Reutens
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
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111
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Räntzsch V, Wilhelm M, Guthausen G. Hyphenated low-field NMR techniques: combining NMR with NIR, GPC/SEC and rheometry. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:494-501. [PMID: 25854997 DOI: 10.1002/mrc.4219] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 12/18/2014] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
Hyphenated low-field NMR techniques are promising characterization methods for online process analytics and comprehensive offline studies of soft materials. By combining different analytical methods with low-field NMR, information on chemical and physical properties can be correlated with molecular dynamics and complementary chemical information. In this review, we present three hyphenated low-field NMR techniques: a combination of near-infrared spectroscopy and time-domain NMR (TD-NMR) relaxometry, online (1) H-NMR spectroscopy measured directly after size exclusion chromatographic (SEC, also known as GPC) separation and a combination of rheometry and TD-NMR relaxometry for highly viscous materials. Case studies are reviewed that underline the possibilities and challenges of the different hyphenated low-field NMR methods. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Volker Räntzsch
- Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute for Technology (KIT), Karlsruhe, 76131, Germany
| | - Manfred Wilhelm
- Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute for Technology (KIT), Karlsruhe, 76131, Germany
| | - Gisela Guthausen
- Pro2NMR, Institute for Biological Interfaces and Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76131, Germany
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112
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Zientek N, Laurain C, Meyer K, Paul A, Engel D, Guthausen G, Kraume M, Maiwald M. Automated data evaluation and modelling of simultaneous (19) F-(1) H medium-resolution NMR spectra for online reaction monitoring. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:513-520. [PMID: 25854892 DOI: 10.1002/mrc.4216] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/31/2014] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
Medium-resolution nuclear magnetic resonance spectroscopy (MR-NMR) currently develops to an important analytical tool for both quality control and process monitoring. In contrast to high-resolution online NMR (HR-NMR), MR-NMR can be operated under rough environmental conditions. A continuous re-circulating stream of reaction mixture from the reaction vessel to the NMR spectrometer enables a non-invasive, volume integrating online analysis of reactants and products. Here, we investigate the esterification of 2,2,2-trifluoroethanol with acetic acid to 2,2,2-trifluoroethyl acetate both by (1) H HR-NMR (500 MHz) and (1) H and (19) F MR-NMR (43 MHz) as a model system. The parallel online measurement is realised by splitting the flow, which allows the adjustment of quantitative and independent flow rates, both in the HR-NMR probe as well as in the MR-NMR probe, in addition to a fast bypass line back to the reactor. One of the fundamental acceptance criteria for online MR-MNR spectroscopy is a robust data treatment and evaluation strategy with the potential for automation. The MR-NMR spectra are treated by an automated baseline and phase correction using the minimum entropy method. The evaluation strategies comprise (i) direct integration, (ii) automated line fitting, (iii) indirect hard modelling (IHM) and (iv) partial least squares regression (PLS-R). To assess the potential of these evaluation strategies for MR-NMR, prediction results are compared with the line fitting data derived from the quantitative HR-NMR spectroscopy. Although, superior results are obtained from both IHM and PLS-R for (1) H MR-NMR, especially the latter demands for elaborate data pretreatment, whereas IHM models needed no previous alignment. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Nicolai Zientek
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489, Berlin, Germany
| | - Clément Laurain
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489, Berlin, Germany
- École Nationale Supérieure de Chimie de Lille, Avenue Mendeleiev CS 90108, 59652, Villeneuve D'ascq Cedex, France
| | - Klas Meyer
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489, Berlin, Germany
| | - Andrea Paul
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489, Berlin, Germany
| | - Dirk Engel
- Pro2NMR, Institute of Mechanical Process Engineering and Mechanics and Institute of Biological Interfaces, KIT, Adenauerring 20b, 76131, Karlsruhe, Germany
| | | | - Matthias Kraume
- Department of Chemical Engineering, Technische Universität Berlin, Straße des 17. Juni 136, MA 5-7, 10623, Berlin, Germany
| | - Michael Maiwald
- BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Straße 11, 12489, Berlin, Germany
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113
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Yilmaz A, Utz M. Characterisation of oxygen permeation into a microfluidic device for cell culture by in situ NMR spectroscopy. LAB ON A CHIP 2016; 16:2079-2085. [PMID: 27149932 DOI: 10.1039/c6lc00396f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A compact microfluidic device for perfusion culture of mammalian cells under in situ metabolomic observation by NMR spectroscopy is presented. The chip is made from poly(methyl methacrylate) (PMMA), and uses a poly(dimethyl siloxane) (PDMS) membrane to allow gas exchange. It is integrated with a generic micro-NMR detector developed recently by our group [J. Magn. Reson., 2016, 262, 73-80]. While PMMA is an excellent material in the context of NMR, PDMS is known to produce strong background signals. To mitigate this, the device keeps the PDMS away from the detection area. The oxygen permeation into the device is quantified using a flow chemistry approach. A solution of glucose is mixed on the chip with a solution of glucose oxidase, before flowing through the gas exchanger. The resulting concentration of gluconate is measured by (1)H NMR spectroscopy as a function of flow rate. An oxygen equilibration rate constant of 2.4 s(-1) is found for the device, which is easily sufficient to maintain normoxic conditions in a cell culture at low perfusion flow rates.
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Affiliation(s)
- Ali Yilmaz
- School of Chemistry, University of Southampton, SO17 1BJ, UK.
| | - Marcel Utz
- School of Chemistry, University of Southampton, SO17 1BJ, UK.
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114
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Parker AJ, Zia W, Rehorn CWG, Blümich B. Shimming Halbach magnets utilizing genetic algorithms to profit from material imperfections. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 265:83-89. [PMID: 26874333 DOI: 10.1016/j.jmr.2016.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/14/2016] [Accepted: 01/19/2016] [Indexed: 06/05/2023]
Abstract
In recent years, permanent magnet-based NMR spectrometers have resurfaced as low-cost portable alternatives to superconducting instruments. While the development of these devices as well as clever shimming methods have yielded impressive advancements, scaling the size of these magnets to miniature lengths remains a problem to be addressed. Here we present the results of a study of a discrete shimming scheme for NMR Mandhalas constructed from a set of individual magnet blocks. While our calculations predict a modest reduction in field deviation by a factor of 9.3 in the case of the shimmed ideal Mandhala, a factor of 28 is obtained in the case of the shimmed imperfect Mandhala. This indicates that imperfections of magnet blocks can lead to improved field homogeneity. We also present a new algorithm to improve the homogeneity of a permanent magnet assembly. Strategies for future magnet construction can improve the agreement between simulation and practical implementation by using data from real magnets in these assemblies as the input to such an algorithm to optimize the homogeneity of a given design.
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Affiliation(s)
- Anna J Parker
- Institut für Technische und Makromolekulare Chemie, RWTH-Aachen University, Worringerweg 2, 52074 Aachen, Germany.
| | - Wasif Zia
- Institut für Technische und Makromolekulare Chemie, RWTH-Aachen University, Worringerweg 2, 52074 Aachen, Germany
| | - Christian W G Rehorn
- Institut für Technische und Makromolekulare Chemie, RWTH-Aachen University, Worringerweg 2, 52074 Aachen, Germany
| | - Bernhard Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH-Aachen University, Worringerweg 2, 52074 Aachen, Germany
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115
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Xiong Y, Wang CJ, Tao T, Duan M, Fang SW, Zheng M. A miniaturized fiber-optic colorimetric sensor for nitrite determination by coupling with a microfluidic capillary waveguide. Anal Bioanal Chem 2016; 408:3413-23. [PMID: 26939671 DOI: 10.1007/s00216-016-9415-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/26/2016] [Accepted: 02/10/2016] [Indexed: 10/22/2022]
Abstract
A microfluidic-capillary-waveguide-coupled fiber-optic sensor was developed for colorimetric determination of hazardous nitrite based on the Griess-Ilosvay reaction. The sensor was modularly designed by use of a light-emitting diode as the light source, silica fiber as the light transmission element, and a capillary waveguide tube as the light reaction flow cell. With the light interacting with the azo dye generated by the Griess-Ilosvay reaction between nitrite and Griess reagents, nitrite could be determined by a colorimetric method according to Beer's law. By use of the inexpensive and micro-sized elements mentioned above, the sensor provided a new low-cost and portable method for in situ and online measurement of nitrite. The sensor had a wide linear range for nitrite from 0.02 to 1.8 mg L(-1) and a low detection limit of 7 μg L(-1) (3σ), with a relative standard deviation of 0.37% (n = 10). With a low reagent demand of 200 μL, a short response time of 6.24 s, and excellent selectivity, the sensor is environmentally friendly and has been applied to nitrite determination in different water samples. The results were compared with those obtained by conventional spectrophotometry and ion chromatography, indicating the sensor's potential for practical applications.
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Affiliation(s)
- Yan Xiong
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China.,Oil and Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan, 610500, China
| | - Cheng-Jie Wang
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China
| | - Tao Tao
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China
| | - Ming Duan
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China. .,Oil and Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan, 610500, China.
| | - Shen-Wen Fang
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China
| | - Min Zheng
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan, 610500, China
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116
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Goldbach M, Danieli E, Perlo J, Kaptein B, Litvinov VM, Blümich B, Casanova F, Duchateau AL. Preparation of Grignard reagents from magnesium metal under continuous flow conditions and on-line monitoring by NMR spectroscopy. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2015.11.077] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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117
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Finch G, Yilmaz A, Utz M. An optimised detector for in-situ high-resolution NMR in microfluidic devices. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 262:73-80. [PMID: 26754062 DOI: 10.1016/j.jmr.2015.11.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 06/05/2023]
Abstract
Integration of high-resolution nuclear magnetic resonance (NMR) spectroscopy with microfluidic lab-on-a-chip devices is challenging due to limited sensitivity and line broadening caused by magnetic susceptibility inhomogeneities. We present a novel double-stripline NMR probe head that accommodates planar microfluidic devices, and obtains the NMR spectrum from a rectangular sample chamber on the chip with a volume of 2μl. Finite element analysis was used to jointly optimise the detector and sample volume geometry for sensitivity and RF homogeneity. A prototype of the optimised design has been built, and its properties have been characterised experimentally. The performance in terms of sensitivity and RF homogeneity closely agrees with the numerical predictions. The system reaches a mass limit of detection of 1.57nmols, comparing very favourably with other micro-NMR systems. The spectral resolution of this chip/probe system is better than 1.75Hz at a magnetic field of 7T, with excellent line shape.
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Affiliation(s)
- Graeme Finch
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Ali Yilmaz
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Marcel Utz
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
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118
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Xiong Y, Wang C, Tao T, Duan M, Tan J, Wu J, Wang D. Fabrication of a miniaturized capillary waveguide integrated fiber-optic sensor for fluoride determination. Analyst 2016; 141:3041-9. [DOI: 10.1039/c6an00159a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fluoride concentration is a key aspect of water quality and essential for human health.
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Affiliation(s)
- Yan Xiong
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation
- Southwest Petroleum University
- Chengdu
- China
- School of Chemistry and Chemical Engineering
| | - Chengjie Wang
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
| | - Tao Tao
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
| | - Ming Duan
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
- Oil and Gas Field Applied Chemistry Key Laboratory of Sichuan Province
| | - Jun Tan
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
| | - Jiayi Wu
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
| | - Dong Wang
- School of Chemistry and Chemical Engineering
- Southwest Petroleum University
- Chengdu
- China
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119
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Hall AMR, Chouler JC, Codina A, Gierth PT, Lowe JP, Hintermair U. Practical aspects of real-time reaction monitoring using multi-nuclear high resolution FlowNMR spectroscopy. Catal Sci Technol 2016. [DOI: 10.1039/c6cy01754a] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
FlowNMR spectroscopy is an excellent technique for non-invasive real-time reaction monitoring under relevant conditions that avoids many of the limitations that bedevil other reaction monitoring techniques.
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Affiliation(s)
- Andrew M. R. Hall
- Centre for Sustainable Chemical Technologies
- University of Bath
- Bath BA2 7AY
- UK
| | - Jonathan C. Chouler
- Centre for Sustainable Chemical Technologies
- University of Bath
- Bath BA2 7AY
- UK
| | | | | | - John P. Lowe
- Department of Chemistry
- University of Bath
- Bath BA2 7AY
- UK
| | - Ulrich Hintermair
- Centre for Sustainable Chemical Technologies
- University of Bath
- Bath BA2 7AY
- UK
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120
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Li G, Cao J, Zong W, Lei X, Tan R. Enantiodiscrimination of carboxylic acids using the diphenylprolinol NMR chiral solvating agents. Org Chem Front 2016. [DOI: 10.1039/c5qo00264h] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Enantiopure diphenylprolinols have been developed as effective and practical NMR chiral solvating agents for the enantiodiscrimination of diverse α-carboxylic acids.
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Affiliation(s)
- Gaowei Li
- Institute of Functional Biomolecules
- State Key Laboratory of Pharmaceutical Biotechnology
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Jiangming Cao
- Institute of Functional Biomolecules
- State Key Laboratory of Pharmaceutical Biotechnology
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Wen Zong
- College of Chemistry & Materials Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Xinxiang Lei
- College of Chemistry & Materials Engineering
- Wenzhou University
- Wenzhou 325035
- P. R. China
| | - Renxiang Tan
- Institute of Functional Biomolecules
- State Key Laboratory of Pharmaceutical Biotechnology
- Nanjing University
- Nanjing 210093
- P. R. China
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121
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Tsedilin AM, Fakhrutdinov AN, Eremin DB, Zalesskiy SS, Chizhov AO, Kolotyrkina NG, Ananikov VP. How sensitive and accurate are routine NMR and MS measurements? MENDELEEV COMMUNICATIONS 2015. [DOI: 10.1016/j.mencom.2015.11.019] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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122
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Adams A, Kwamen R, Woldt B, Graß M. Nondestructive Quantification of Local Plasticizer Concentration in PVC by (1)H NMR Relaxometry. Macromol Rapid Commun 2015; 36:2171-5. [PMID: 26437600 DOI: 10.1002/marc.201500409] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/01/2015] [Indexed: 01/06/2023]
Abstract
The properties of plasticized poly(vinyl chloride) (PVC) , one of the most important polymers today, are strongly dictated by the concentration of plasticizer. Yet, it has been impossible to quantify this concentration at different positions inside a PVC product without its destruction because of a lack of suitable analytical methods. Thus, this paper introduces a simple, fast, and efficient way to determine truly nondestructively the concentration of plasticizer in PVC by single-sided nuclear magnetic resonance (NMR). With the help of correlation curves between the concentration of plasticizer inside nonaged PVC samples and the corresponding volume-averaged NMR parameters, single-sided NMR allows the quantification of the local concentration of plasticizer in aged PVC plates at different depths by spatially resolved relaxation measurements. The presented approach represents a fundamental step toward in situ characterization of plasticized PVC.
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Affiliation(s)
- Alina Adams
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Templergraben 55, D-52056, Aachen, Germany
| | - Rance Kwamen
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Templergraben 55, D-52056, Aachen, Germany
| | - Benjamin Woldt
- Evonik Industries AG, Paul-Baumann-Straße 1, D-45772, Marl, Germany
| | - Michael Graß
- Evonik Industries AG, Paul-Baumann-Straße 1, D-45772, Marl, Germany
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123
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Gomez MV, Rodriguez AM, de la Hoz A, Jimenez-Marquez F, Fratila RM, Barneveld PA, Velders AH. Determination of Kinetic Parameters within a Single Nonisothermal On-Flow Experiment by Nanoliter NMR Spectroscopy. Anal Chem 2015; 87:10547-55. [DOI: 10.1021/acs.analchem.5b02811] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- M. Victoria Gomez
- Instituto Regional de Investigación Cientifica Aplicada, Campus Universitario, Avenida Camilo
José Cela s/n, 13071 Ciudad Real, Spain
| | - Antonio M. Rodriguez
- Instituto Regional de Investigación Cientifica Aplicada, Campus Universitario, Avenida Camilo
José Cela s/n, 13071 Ciudad Real, Spain
| | - Antonio de la Hoz
- Instituto Regional de Investigación Cientifica Aplicada, Campus Universitario, Avenida Camilo
José Cela s/n, 13071 Ciudad Real, Spain
| | - Francisco Jimenez-Marquez
- Escuela
Técnica Superior de Ingenieros (ETSI) Industriales, Universidad de Castilla-La Mancha, Avenida Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - Raluca M. Fratila
- Instituto
de Nanociencia de Aragon (INA), Universidad de Zaragoza, C/Mariano
Esquillor s/n, 50018 Zaragoza, Spain
- Fundación Agencia Aragonesa para la Investigación y Desarrollo (ARAID), C/María
de Luna 11, 50018 Zaragoza, Spain
| | | | - Aldrik H. Velders
- Instituto Regional de Investigación Cientifica Aplicada, Campus Universitario, Avenida Camilo
José Cela s/n, 13071 Ciudad Real, Spain
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124
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Nakamura T, Tamada D, Yanagi Y, Itoh Y, Nemoto T, Utumi H, Kose K. Development of a superconducting bulk magnet for NMR and MRI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 259:68-75. [PMID: 26295170 DOI: 10.1016/j.jmr.2015.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 06/04/2023]
Abstract
A superconducting bulk magnet composed of six vertically stacked annular single-domain c-axis-oriented Eu-Ba-Cu-O crystals was energized to 4.74 T using a conventional superconducting magnet for high-resolution NMR spectroscopy. Shim coils, gradient coils, and radio frequency coils for high resolution NMR and MRI were installed in the 23 mm-diameter room-temperature bore of the bulk magnet. A 6.9 ppm peak-to-peak homogeneous region suitable for MRI was achieved in the central cylindrical region (6.2 mm diameter, 9.1 mm length) of the bulk magnet by using a single layer shim coil. A 21 Hz spectral resolution that can be used for high resolution NMR spectroscopy was obtained in the central cylindrical region (1.3 mm diameter, 4 mm length) of the bulk magnet by using a multichannel shim coil. A clear 3D MR image dataset of a chemically fixed mouse fetus with (50 μm)(3) voxel resolution was obtained in 5.5 h. We therefore concluded that the cryogen-free superconducting bulk magnet developed in this study is useful for high-resolution desktop NMR, MRI and mobile NMR device.
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Affiliation(s)
| | - Daiki Tamada
- Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan
| | | | | | | | | | - Katsumi Kose
- Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan.
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125
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Kock FVC, Colnago LA. Rapid and simultaneous relaxometric methods to study paramagnetic ion complexes in solution: An alternative to spectrophotometry. Microchem J 2015. [DOI: 10.1016/j.microc.2015.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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126
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Abstract
This minireview discusses universal electronic modules (generic programmable units) and their use by analytical chemists to construct inexpensive, miniature or automated devices. Recently, open-source platforms have gained considerable popularity among tech-savvy chemists because their implementation often does not require expert knowledge and investment of funds. Thus, chemistry students and researchers can easily start implementing them after a few hours of reading tutorials and trial-and-error. Single-board microcontrollers and micro-computers such as Arduino, Teensy, Raspberry Pi or BeagleBone enable collecting experimental data with high precision as well as efficient control of electric potentials and actuation of mechanical systems. They are readily programmed using high-level languages, such as C, C++, JavaScript or Python. They can also be coupled with mobile consumer electronics, including smartphones as well as teleinformatic networks. More demanding analytical tasks require fast signal processing. Field-programmable gate arrays enable efficient and inexpensive prototyping of high-performance analytical platforms, thus becoming increasingly popular among analytical chemists. This minireview discusses the advantages and drawbacks of universal electronic modules, considering their application in prototyping and manufacture of intelligent analytical instrumentation.
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Affiliation(s)
- Pawel L Urban
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
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127
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Ananikov VP, Khokhlova EA, Egorov MP, Sakharov AM, Zlotin SG, Kucherov AV, Kustov LM, Gening ML, Nifantiev NE. Organic and hybrid molecular systems. MENDELEEV COMMUNICATIONS 2015. [DOI: 10.1016/j.mencom.2015.03.001] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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128
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Next-generation technologies for multiomics approaches including interactome sequencing. BIOMED RESEARCH INTERNATIONAL 2015; 2015:104209. [PMID: 25649523 PMCID: PMC4306365 DOI: 10.1155/2015/104209] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/30/2014] [Accepted: 08/31/2014] [Indexed: 11/17/2022]
Abstract
The development of high-speed analytical techniques such as next-generation sequencing and microarrays allows high-throughput analysis of biological information at a low cost. These techniques contribute to medical and bioscience advancements and provide new avenues for scientific research. Here, we outline a variety of new innovative techniques and discuss their use in omics research (e.g., genomics, transcriptomics, metabolomics, proteomics, and interactomics). We also discuss the possible applications of these methods, including an interactome sequencing technology that we developed, in future medical and life science research.
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129
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Camaiti M, Bortolotti V, Fantazzini P. Stone porosity, wettability changes and other features detected by MRI and NMR relaxometry: a more than 15-year study. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:34-47. [PMID: 25322710 DOI: 10.1002/mrc.4163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 09/15/2014] [Accepted: 09/18/2014] [Indexed: 06/04/2023]
Abstract
Scientists applying magnetic resonance techniques to cultural heritage are now a quite vast and international community, even if these applications are not yet well known outside this community. Not only laboratory experiments but also measurements in the field are now possible, with the use of portable nuclear magnetic resonance (NMR) instruments that enable non-invasive and non-destructive studies on items of any size, of high artistic and historical value as well as diagnosis of their conservation state. The situation was completely different in the second half of the 1990s when our group started working on applications of NMR to cultural heritage, by combining the knowledge of NMR for fluids in porous media at the University of Bologna, with the skilfulness of the chemists for cultural heritage of CNR and University of Florence, and Safeguarding Cultural Heritage Department of Aosta. Since then, our interest has been mainly devoted to develop methods to study the structure of pore space and their changes as a result of the decay, as well as to evaluate performance of the protective and conservative treatments of porous materials like stone, ceramic, cements and wood. In this paper, we will review the pathway that led us from the first tentative experiments, in the second half of the 1990s to the current work on these topics.
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Affiliation(s)
- Mara Camaiti
- Institute for Geosciences and Earth Resources-CNR Section of Florence, Via La Pira, 4, 50121, Florence, Italy; Centro Enrico Fermi, Piazza del Viminale 1, 00184, Rome, Italy
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130
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Barskiy DA, Kovtunov KV, Koptyug IV, He P, Groome KA, Best QA, Shi F, Goodson BM, Shchepin RV, Truong ML, Coffey AM, Waddell KW, Chekmenev EY. In situ and ex situ low-field NMR spectroscopy and MRI endowed by SABRE hyperpolarization. Chemphyschem 2014; 15:4100-7. [PMID: 25367202 PMCID: PMC4287267 DOI: 10.1002/cphc.201402607] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 09/26/2014] [Indexed: 12/11/2022]
Abstract
By using 5.75 and 47.5 mT nuclear magnetic resonance (NMR) spectroscopy, up to 10(5)-fold sensitivity enhancement through signal amplification by reversible exchange (SABRE) was enabled, and subsecond temporal resolution was used to monitor an exchange reaction that resulted in the buildup and decay of hyperpolarized species after parahydrogen bubbling. We demonstrated the high-resolution low-field proton magnetic resonance imaging (MRI) of pyridine in a 47.5 mT magnetic field endowed by SABRE. Molecular imaging (i.e. imaging of dilute hyperpolarized substances rather than the bulk medium) was conducted in two regimes: in situ real-time MRI of the reaction mixture (in which pyridine was hyperpolarized), and ex situ MRI (in which hyperpolarization decays) of the liquid hyperpolarized product. Low-field (milli-Tesla range, e.g. 5.75 and 47.5 mT used in this study) parahydrogen-enhanced NMR and MRI, which are free from the limitations of high-field magnetic resonance (including susceptibility-induced gradients of the static magnetic field at phase interfaces), potentially enables new imaging applications as well as differentiation of hyperpolarized chemical species on demand by exploiting spin manipulations with static and alternating magnetic fields.
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Affiliation(s)
- Danila A. Barskiy
- Laboratory of Magnetic Resonance Microimaging, International Tomography Center, SB RAS, 3 A Institutskaya St., Novosibirsk 630090 (Russia)
| | - Kirill V. Kovtunov
- Laboratory of Magnetic Resonance Microimaging, International Tomography Center, SB RAS, 3 A Institutskaya St., Novosibirsk 630090 (Russia)
| | - Igor V. Koptyug
- Laboratory of Magnetic Resonance Microimaging, International Tomography Center, SB RAS, 3 A Institutskaya St., Novosibirsk 630090 (Russia)
| | - Ping He
- Department of Chemistry and Biochemistry, Southern Illinois University, Materials Technology Center, Carbondale, Illinois, 62901 (USA)
| | - Kirsten A. Groome
- Department of Chemistry and Biochemistry, Southern Illinois University, Materials Technology Center, Carbondale, Illinois, 62901 (USA)
| | - Quinn A. Best
- Department of Chemistry and Biochemistry, Southern Illinois University, Materials Technology Center, Carbondale, Illinois, 62901 (USA)
| | - Fan Shi
- Department of Chemistry and Biochemistry, Southern Illinois University, Materials Technology Center, Carbondale, Illinois, 62901 (USA)
| | - Boyd M. Goodson
- Department of Chemistry and Biochemistry, Southern Illinois University, Materials Technology Center, Carbondale, Illinois, 62901 (USA)
| | - Roman V. Shchepin
- Institute of Imaging Science, Department of Radiology, Department of Biomedical Engineering, Department of Physics and Astronomy and Department of Biochemistry, Vanderbilt University, 1161 21 st Ave South AA-1107, Nashville, Tennessee, 37232-2310 (USA)
| | - Milton L. Truong
- Institute of Imaging Science, Department of Radiology, Department of Biomedical Engineering, Department of Physics and Astronomy and Department of Biochemistry, Vanderbilt University, 1161 21 st Ave South AA-1107, Nashville, Tennessee, 37232-2310 (USA)
| | - Aaron M. Coffey
- Institute of Imaging Science, Department of Radiology, Department of Biomedical Engineering, Department of Physics and Astronomy and Department of Biochemistry, Vanderbilt University, 1161 21 st Ave South AA-1107, Nashville, Tennessee, 37232-2310 (USA)
| | - Kevin W. Waddell
- Institute of Imaging Science, Department of Radiology, Department of Biomedical Engineering, Department of Physics and Astronomy and Department of Biochemistry, Vanderbilt University, 1161 21 st Ave South AA-1107, Nashville, Tennessee, 37232-2310 (USA)
| | - Eduard Y. Chekmenev
- Institute of Imaging Science, Department of Radiology, Department of Biomedical Engineering, Department of Physics and Astronomy and Department of Biochemistry, Vanderbilt University, 1161 21 st Ave South AA-1107, Nashville, Tennessee, 37232-2310 (USA)
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131
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Ha D, Paulsen J, Sun N, Song YQ, Ham D. Scalable NMR spectroscopy with semiconductor chips. Proc Natl Acad Sci U S A 2014; 111:11955-60. [PMID: 25092330 PMCID: PMC4143061 DOI: 10.1073/pnas.1402015111] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
State-of-the-art NMR spectrometers using superconducting magnets have enabled, with their ultrafine spectral resolution, the determination of the structure of large molecules such as proteins, which is one of the most profound applications of modern NMR spectroscopy. Many chemical and biotechnological applications, however, involve only small-to-medium size molecules, for which the ultrafine resolution of the bulky, expensive, and high-maintenance NMR spectrometers is not required. For these applications, there is a critical need for portable, affordable, and low-maintenance NMR spectrometers to enable in-field, on-demand, or online applications (e.g., quality control, chemical reaction monitoring) and co-use of NMR with other analytical methods (e.g., chromatography, electrophoresis). As a critical step toward NMR spectrometer miniaturization, small permanent magnets with high field homogeneity have been developed. In contrast, NMR spectrometer electronics capable of modern multidimensional spectroscopy have thus far remained bulky. Complementing the magnet miniaturization, here we integrate the NMR spectrometer electronics into 4-mm(2) silicon chips. Furthermore, we perform various multidimensional NMR spectroscopies by operating these spectrometer electronics chips together with a compact permanent magnet. This combination of the spectrometer-electronics-on-a-chip with a permanent magnet represents a useful step toward miniaturization of the overall NMR spectrometer into a portable platform.
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Affiliation(s)
- Dongwan Ha
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
| | | | - Nan Sun
- Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX 78712
| | - Yi-Qiao Song
- Schlumberger-Doll Research Center, Cambridge, MA 02139; and
| | - Donhee Ham
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138;
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