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Lee SJ, Yu KK, Hwang SM, Oh S, Song NW, Jung HS, Han OH, Shim JH. Chemical Analysis of an Isotopically Labeled Molecule Using Two-Dimensional NMR Spectroscopy at 34 μT. ACS OMEGA 2023; 8:37302-37308. [PMID: 37841117 PMCID: PMC10568728 DOI: 10.1021/acsomega.3c05128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 09/21/2023] [Indexed: 10/17/2023]
Abstract
Low-field nuclear magnetic resonance (NMR) spectroscopy, conducted at or below a few millitesla, provides only limited spectral information due to its inability to resolve chemical shifts. Thus, chemical analysis based on this technique remains challenging. One potential solution to overcome this limitation is the use of isotopically labeled molecules. However, such compounds, particularly their use in two-dimensional (2D) NMR techniques, have rarely been studied. This study presents the results of both experimental and simulated correlation spectroscopy (COSY) on 1-13C-ethanol at 34.38 μT. The strong heteronuclear coupling in this molecule breaks the magnetic equivalence, causing all J-couplings, including homonuclear coupling, to split the 1H spectrum. The obtained COSY spectrum clearly shows the spectral details. Furthermore, we observed that homonuclear coupling between 1H spins generated cross-peaks only when the associated 1H spins were coupled to identical 13C spin states. Our findings demonstrate that a low-field 2D spectrum, even with a moderate spectral line width, can reveal the J-coupling networks of isotopically labeled molecules.
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Affiliation(s)
- Seong-Joo Lee
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
| | - Kwon Kyu Yu
- Center
for Superconducting Quantum Computing System, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Seong-min Hwang
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
| | - Sangwon Oh
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
| | - Nam Woong Song
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
| | - Hak-Sung Jung
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
| | - Oc Hee Han
- Western
Seoul Center, Korea Basic Science Institute, Seoul 03759, Republic of Korea
- Graduate
School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jeong Hyun Shim
- Quantum
Magnetic Imaging Team, Korea Research Institute
of Standards and Science, Daejeon 34113, Republic
of Korea
- Department
of Applied Measurement Science, University
of Science and Technology, Daejeon 34113, Republic
of Korea
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2
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Altenhof AR, Kaseman DC, Mason HE, Alvarez MA, Malone MW, Williams RF. On the effects of quadrupolar relaxation in Earth's field NMR spectra. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 355:107540. [PMID: 37722217 DOI: 10.1016/j.jmr.2023.107540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/11/2023] [Accepted: 08/15/2023] [Indexed: 09/20/2023]
Abstract
There is growing interest in using low-field magnetic resonance experiments for routine chemical characterization. Earth's field NMR is one such technique that can garner structural information and enable sample differentiation with low cost and highly portable designs. The resulting NMR spectra are primarily influenced by J-couplings, resulting in so-called J-coupled spectra (JCS). Many small molecules include atoms with NMR-active nuclei that are quadrupolar either at natural abundance or are often isotopically enriched (e.g.,2H, 6Li, 11B, 14N, 17O, etc.) where the effects of quadrupolar J-couplings and relaxation on JCS of strongly- and weakly-coupled spin systems have not been explored to date. Herein, using a set of seven fluoropyridine samples with unique substitution and J-couplings, we demonstrate that the 14N relaxation rates can induce drastic line-broadening in the JCS. This includes a previously unexplored unique line broadening mechanism enabled by strongly coupled spins at low-field. Numerical simulations are used to model and refine the magnitudes and signs of J-couplings, as well as indirectly determine the 14N relaxation rates in a single 1D experiment that has a higher fidelity than observed in high-field NMR experiments.
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Affiliation(s)
- Adam R Altenhof
- MPA-Q, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | | | - Harris E Mason
- C-IIAC, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Marc A Alvarez
- B-TEK, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Michael W Malone
- MPA-Q, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
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3
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Topor A, Voda MA, Vasos PR. Earth's field NMR relaxation of pre-polarised water protons for real-time detection of free-radical formation. Chem Commun (Camb) 2023; 59:11672-11675. [PMID: 37695610 DOI: 10.1039/d3cc02502k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Real-time imaging of free-radical formation is important in physical chemistry, biochemistry, and radiobiology, especially for the study of radiation dose-rate effects. Herein, we show for the first time that the formation of free radicals during the time course of a chemical reaction can be imaged through NMR relaxation measurements of water protons in the Earth's magnetic field, in an open-coil spectrometer. The relaxation rate constants of water magnetisation are enhanced as reactions leading to the formation of hydroxyl radicals and oxygen proceed on the timescale of tens of minutes. The reaction rate of iodide-catalysed H2O2 decay was followed by Earth-field 1H NMR relaxation in real time. The relaxivities of the reaction product and several other paramagnetic compounds were determined. Spin-trap molecules were then used to capture ˙OH radical species, thus altering the reaction rate in proportion to the formation of new paramagnetic compounds. Thereby, a new experimental method for magnetic resonance imaging of the formation of intermediate and stable radical species in water is proposed.
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Affiliation(s)
- Alexandru Topor
- Biophysics and Biomedical Applications Group and Laboratory, Extreme Light Infrastructure-Nuclear Physics (ELI-NP), Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering (IFIN-HH), Reactorului Str. 30, Bucharest-Magurele 077125, Romania
- University of Bucharest, Doctoral School of Chemistry, 4-12 Regina Elisabeta Bd, 030018 Bucharest, Romania
- C. D. Nenitzescu Institute of Organic and Supramolecular Chemistry, 202B Splaiul Independenţei Bucharest, Romania
| | - Mihai A Voda
- Biophysics and Biomedical Applications Group and Laboratory, Extreme Light Infrastructure-Nuclear Physics (ELI-NP), Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering (IFIN-HH), Reactorului Str. 30, Bucharest-Magurele 077125, Romania
| | - Paul R Vasos
- Biophysics and Biomedical Applications Group and Laboratory, Extreme Light Infrastructure-Nuclear Physics (ELI-NP), Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering (IFIN-HH), Reactorului Str. 30, Bucharest-Magurele 077125, Romania
- University of Bucharest, Interdisciplinary School of Doctoral Studies, ISDS, 4-12 Regina Elisabeta Bd, 030018 Bucharest, Romania.
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4
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Kaseman DC, Batrice RJ, Williams RF. Detection of natural abundance 13C J-couplings at Earth's magnetic field for spin system differentiation of small organic molecules. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 342:107272. [PMID: 35917767 DOI: 10.1016/j.jmr.2022.107272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/14/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy routinely characterizes the unique spin systems of molecules using a combination of chemical shift and J-coupling interactions for the 1H and 13C nuclei. However, at Earth's magnetic field, chemical shifts are unresolvable and the ability to characterize structure relies solely on the J-couplings. Fortuitously, the J-couplings at Earth's field provides the same spin system information as high field, but only requires detection of the 1H nucleus. We report the first identification of the multiple natural abundance 1H-13C spin systems on organic molecules detected at Earth's magnetic field. The results clearly demonstrate the feasibility of Earth's field NMR to characterize small organic molecules without costly enrichment strategies.
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Affiliation(s)
- Derrick C Kaseman
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, NM 87545, United States; Nuclear Magnetic Resonance Facility, University of California Davis, Davis, CA 95616, United States.
| | - Rami J Batrice
- Chemical Diagnostics and Engineering Group, Los Alamos National Laboratory, Los Alamos, NM 87545, United States
| | - Robert F Williams
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, NM 87545, United States
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5
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Chen K, Wu T, Jiang M, Li A, Peng X, Chen S, Yang Z, Zhou X, Zheng X, Jiang ZX. Partially fluorinated nanoemulsions for 19F MRI-fluorescence dual imaging cell tracking. Colloids Surf B Biointerfaces 2022; 215:112493. [PMID: 35430486 DOI: 10.1016/j.colsurfb.2022.112493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 03/23/2022] [Accepted: 04/05/2022] [Indexed: 12/29/2022]
Abstract
Fluorine-19 magnetic resonance imaging (19F MRI) has been a technology of choice for in vivo cell tracking, in which perfluorocarbons (PFCs) nanoemulsions are the most used 19F MRI agents. However, the peculiar physicochemical properties of PFCs may lead to poor cell uptake and misleading cell tracking results. Herein, we employed partially fluorinated aromatic agents to formulate paramagnetic nanoemulsions as novel 19F MRI-fluorescence (FL) dual imaging agents for cell tracking. With the intramolecular π-π interaction, low density and fluorine content, the partially fluorinated agents enable considerable solubilities of functional agents and short relaxation times, which facilitates convenient preparation of stable, biocompatible, and multifunctional nanoemulsions with high 19F MRI sensitivity. Replacing PFCs in 19F MRI nanoemulsions with readily available partially fluorinated aromatic agents may address many issues associated with PFCs and provide a novel strategy for high-performance 19F MRI agents of broad biomedical applications.
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Affiliation(s)
- Kexin Chen
- Group of Lead Compound, Department of Pharmacy, Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang 421001, China; Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Tingjuan Wu
- Group of Lead Compound, Department of Pharmacy, Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang 421001, China; Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Mou Jiang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China
| | - Anfeng Li
- Group of Lead Compound, Department of Pharmacy, Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang 421001, China; Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Xingxing Peng
- Group of Lead Compound, Department of Pharmacy, Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang 421001, China; Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Shizhen Chen
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China
| | - Zhigang Yang
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Xin Zhou
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China
| | - Xing Zheng
- Group of Lead Compound, Department of Pharmacy, Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang 421001, China.
| | - Zhong-Xing Jiang
- Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China.
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6
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Parzy E, Boudries D, Jacoutot S, Albalat M, Vanthuyne N, Franconi JM, Mellet P, Thiaudiere E, Audran G, Marque SRA, Massot P. Enzymatic activity monitoring through dynamic nuclear polarization in Earth magnetic field. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 333:107095. [PMID: 34749037 DOI: 10.1016/j.jmr.2021.107095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/21/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
Cost-effective and portable MRI systems operating at Earth-field would be helpful in poorly accessible areas or in developing nations. Furthermore Earth-field MRI can provide new contrasts opening the way to the observation of pathologies at the biochemical level. However low-field MRI suffers from a dramatic lack in detection sensitivity even worsened for molecular imaging purposes where biochemical specificity requires detection of dilute compounds. In a preliminary spectroscopic approach, it is proposed here to detect protease-driven hydrolysis of a nitroxide probe thanks to electron-nucleus Overhauser enhancement in a home-made double resonance system in Earth-field. The combination of the Overhauser effect and the specific enzymatic modification of the probe provides a smart contrast reporting the enzymatic activity. The nitroxide probe is a six-line nitroxide which lines are shifted according to its substrate/product state, which requires quantum mechanical calculations to predict EPR line frequencies and Overhauser enhancements at Earth field. The NMR system is equipped with a 13-mT prepolarization coil, a 153-MHz EPR coil and a 2-kHz NMR coil. Either prepolarized NMR or DNP-NMR without prepolarization provide NMR spectra within 3 min. The frequency dependence of Overhauser enhancement was in agreement with theoretical calculations. Protease-mediated catalysis of the nitroxide probe could only be measured through the Overhauser effect with 5 min time resolution. Future developments shall open the way for the design of new low-field DNP-MRI systems.
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Affiliation(s)
- E Parzy
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France.
| | - D Boudries
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France
| | - Samuel Jacoutot
- Aix Marseille Univ, CNRS, ICR, Case 551, 13397 Marseille, France
| | | | | | - J-M Franconi
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France
| | - P Mellet
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France; INSERM, Bordeaux
| | - E Thiaudiere
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France
| | - G Audran
- Aix Marseille Univ, CNRS, ICR, Case 551, 13397 Marseille, France
| | - S R A Marque
- Aix Marseille Univ, CNRS, ICR, Case 551, 13397 Marseille, France
| | - P Massot
- Magnetic Resonance of Biological Systems, UMR5536 University of Bordeaux-CNRS, Bordeaux, France
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7
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Gong X, Chen S, Zhang S. JOM-4S Overhauser Magnetometer and Sensitivity Estimation. SENSORS (BASEL, SWITZERLAND) 2021; 21:7698. [PMID: 34833789 PMCID: PMC8624099 DOI: 10.3390/s21227698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/17/2021] [Accepted: 11/17/2021] [Indexed: 11/29/2022]
Abstract
The Overhauser magnetometer is a scalar quantum magnetometer based on the dynamic nuclear polarization (DNP) effect in the Earth's magnetic field. Sensitivity is a key technical specification reflecting the ability of instruments to sense small variations of the Earth's magnetic field and is closely related to the signal-to-noise ratio (SNR) of the free induction decay (FID) signal. In this study, deuterated 15N TEMPONE radical is used in our sensor to obtain high DNP enhancement. The measured SNR of the FID signal is approximately 63/1, and the transverse relaxation time T2 is 2.68 s. The direct measurement method with a single instrument and the synchronous measurement method with two instruments are discussed for sensitivity estimation in time and frequency domains under different electromagnetic interference (EMI) environments and different time periods. For the first time, the correlation coefficient of the magnetic field measured by the two instruments is used to judge the degree of the influence of the environmental noise on the sensitivity estimation. The sensitivity evaluation in the field environment is successfully realized without electrical and magnetic shields. The direct measurement method is susceptible to EMI and cannot work in general electromagnetic environments, except it is sufficiently quiet. The synchronous measurement method has an excellent ability to remove most natural and artificial EMIs and can be used under noisy environments. Direct and synchronous experimental results show that the estimated sensitivity of the JOM-4S magnetometer is approximately 0.01 nT in time domain and approximately 0.01 nT/Hz in frequency domain at a 3 s cycling time. This study provides a low-cost, simple, and effective sensitivity estimation method, which is especially suitable for developers and users to estimate the performance of the instrument.
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Affiliation(s)
| | | | - Shuang Zhang
- College of Electronic Science and Engineering, Jilin University, Changchun 130012, China; (X.G.); (S.C.)
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8
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Fehling P, Buckenmaier K, Dobrynin SA, Morozov DA, Polienko YF, Khoroshunova YV, Borozdina Y, Mayer P, Engelmann J, Scheffler K, Angelovski G, Kirilyuk IA. The effects of nitroxide structure upon 1H Overhauser dynamic nuclear polarization efficacy at ultralow-field. J Chem Phys 2021; 155:144203. [PMID: 34654311 DOI: 10.1063/5.0064342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The efficacy in 1H Overhauser dynamic nuclear polarization in liquids at ultralow magnetic field (ULF, B0 = 92 ± 0.8 µT) and polarization field (Bp = 1-10 mT) was studied for a broad variety of 26 different spin probes. Among others, piperidine, pyrrolidine, and pyrroline radicals specifically synthesized for this study, along with some well-established commercially available nitroxides, were investigated. Isotope-substituted variants, some sterically shielded reduction-resistant nitroxides, and some biradicals were included in the measurements. The maximal achievable enhancement, Emax, and the radio frequency power, P1/2, needed for reaching Emax/2 were measured. Physico-chemical features such as molecular weight, spectral linewidth, heterocyclic structure, different types of substituents, deuteration, and 15N-labeling as well as the difference between monoradicals and biradicals were investigated. For the unmodified nitroxide radicals, the Emax values correlate with the molecular weight. The P1/2 values correlate with the spectral linewidth and are additionally influenced by the type of substituents neighboring the nitroxide group. The nitroxide biradicals with high intramolecular spin-spin coupling show low performance. Nitroxides enriched with 15N and/or 2H afford significantly higher |Emax| and require lower power to do so, compared to their unmodified counterparts containing at natural abundance predominantly 14N and 1H. The results allow for a correlation of chemical features with physical hyperpolarization-related properties and indicate that small nitroxides with narrow spectral lines have clear advantages for the use in Overhauser dynamic nuclear polarization experiments. Perdeuteration and 15N-labeling can be used to additionally boost the spin probe performance.
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Affiliation(s)
- Paul Fehling
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Kai Buckenmaier
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Sergey A Dobrynin
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Denis A Morozov
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yuliya F Polienko
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yulia V Khoroshunova
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yulia Borozdina
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Philipp Mayer
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Jörn Engelmann
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Klaus Scheffler
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Goran Angelovski
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Igor A Kirilyuk
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
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Li Y, Ma P, Tao Q, Krause HJ, Yang S, Ding G, Dong H, Xie X. Magnetic graphene quantum dots facilitate closed-tube one-step detection of SARS-CoV-2 with ultra-low field NMR relaxometry. SENSORS AND ACTUATORS. B, CHEMICAL 2021; 337:129786. [PMID: 33753963 PMCID: PMC7959688 DOI: 10.1016/j.snb.2021.129786] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 05/04/2023]
Abstract
The rapid and sensitive diagnosis of the highly contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the crucial issues at the outbreak of the ongoing global pandemic that has no valid cure. Here, we propose a SARS-CoV-2 antibody conjugated magnetic graphene quantum dots (GQDs)-based magnetic relaxation switch (MRSw) that specifically recognizes the SARS-CoV-2. The probe of MRSw can be directly mixed with the test sample in a fully sealed vial without sample pretreatment, which largely reduces the testers' risk of infection during the operation. The closed-tube one-step strategy to detect SARS-CoV-2 is developed with home-made ultra-low field nuclear magnetic resonance (ULF NMR) relaxometry working at 118 μT. The magnetic GQDs-based probe shows ultra-high sensitivity in the detection of SARS-CoV-2 due to its high magnetic relaxivity, and the limit of detection is optimized to 248 Particles mL‒1. Meanwhile, the detection time in ULF NMR system is only 2 min, which can significantly improve the efficiency of detection. In short, the magnetic GQDs-based MRSw coupled with ULF NMR can realize a rapid, safe, and sensitive detection of SARS-CoV-2.
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Key Words
- AFM, atomic force microscopy
- Ab, specific antibody against SARS-CoV-2 antigen S protein
- BSA, bull serum albumin
- COVID-19, coronavirus disease 2019
- ELISA, enzyme-linked immune-sorbent assay
- Fe3O4, ferrosoferric oxide
- GPG, Gd3+ loaded PEG modified GQDs
- GQDs, graphene quantum dots
- Graphene quantum dots
- HR-TEM, high resolution TEM
- LOD, limit of detection
- MNPs, magnetic nanoparticles
- MRSw, magnetic relaxation switch
- Magnetic relaxation switch
- NMR, nuclear magnetic resonance
- OSR, outer sphere relaxation theory
- PBS, phosphate buffer saline
- PEG, polyethylene glycol
- PEG6, hexaethylene glycol
- RT-PCR, reverse transcription-polymerase chain reaction
- S protein, spike protein
- SARS-CoV-2
- SARS-CoV-2, severe acute respiratory syndrome coronavirus 2
- SD, standard deviation
- SQUID, superconducting quantum interface device
- Spike
- T1, longitudinal relaxation time
- TEM, transmission electron microscopy
- ULF NMR, ultra-low field NMR
- Ultra-low field nuclear magnetic resonance
- XPS, X-ray photoelectron spectroscopy
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Affiliation(s)
- Yongqiang Li
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- CAS Center for ExcelleNce in Superconducting Electronics (CENSE), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
| | - Peixiang Ma
- Shanghai Institute for Advanced Immunological Studies, ShanghaiTech University, Shanghai, 201210, PR China
| | - Quan Tao
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- CAS Center for ExcelleNce in Superconducting Electronics (CENSE), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
| | - Hans-Joachim Krause
- Institute of Biological Information Processing (IBI-3), Forschungszentrum Jülich (FZJ), D-52425, Jülich, Germany
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
| | - Siwei Yang
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
| | - Guqiao Ding
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
| | - Hui Dong
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- CAS Center for ExcelleNce in Superconducting Electronics (CENSE), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
| | - Xiaoming Xie
- State Key Laboratory of Functional Materials of Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai, 200050, PR China
- CAS Center for ExcelleNce in Superconducting Electronics (CENSE), Chinese Academy of Sciences, Shanghai, 200050, PR China
- Joint Research Institute on Functional Materials and Electronics, Collaboration between SIMIT and FZJ, Germany
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, PR China
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10
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Abhyankar N, Szalai V. Challenges and Advances in the Application of Dynamic Nuclear Polarization to Liquid-State NMR Spectroscopy. J Phys Chem B 2021; 125:5171-5190. [PMID: 33960784 PMCID: PMC9871957 DOI: 10.1021/acs.jpcb.0c10937] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful method to study the molecular structure and dynamics of materials. The inherently low sensitivity of NMR spectroscopy is a consequence of low spin polarization. Hyperpolarization of a spin ensemble is defined as a population difference between spin states that far exceeds what is expected from the Boltzmann distribution for a given temperature. Dynamic nuclear polarization (DNP) can overcome the relatively low sensitivity of NMR spectroscopy by using a paramagnetic matrix to hyperpolarize a nuclear spin ensemble. Application of DNP to NMR can result in sensitivity gains of up to four orders of magnitude compared to NMR without DNP. Although DNP NMR is now more routinely utilized for solid-state (ss) NMR spectroscopy, it has not been exploited to the same degree for liquid-state samples. This Review will consider challenges and advances in the application of DNP NMR to liquid-state samples. The Review is organized into four sections: (i) mechanisms of DNP NMR relevant to hyperpolarization of liquid samples; (ii) applications of liquid-state DNP NMR; (iii) available detection schemes for liquid-state samples; and (iv) instrumental challenges and outlook for liquid-state DNP NMR.
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Affiliation(s)
- Nandita Abhyankar
- Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742, USA,National Institute of Standards and Technology, Gaithersburg, MD 20899, USA,Corresponding authors: ,
| | - Veronika Szalai
- National Institute of Standards and Technology, Gaithersburg, MD 20899, USA,Corresponding authors: ,
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11
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Michal CA. Low-cost low-field NMR and MRI: Instrumentation and applications. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 319:106800. [PMID: 33036708 PMCID: PMC7538153 DOI: 10.1016/j.jmr.2020.106800] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/25/2020] [Accepted: 07/26/2020] [Indexed: 05/29/2023]
Abstract
While NMR and MRI are often thought of as expensive techniques requiring large institutional investment, opportunities for low-cost, low-field NMR and MRI abound. We discuss a number of approaches to performing magnetic resonance experiments with inexpensive, easy to find or build components, aimed at applications in industry, education, and research. Opportunities that aim to make NMR accessible to a broad community are highlighted. We describe and demonstrate some projects from our laboratory, including a new prototype instrument for measurements at frequencies up to ∼200 kHz and demonstrate its application to the study of the rapidly advancing technique known as inhomogeneous magnetization transfer imaging, a promising method for characterizing myelin in vivo.
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Affiliation(s)
- Carl A Michal
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada.
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12
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Chemical Analysis of Fluorobenzenes via Multinuclear Detection in the Strong Heteronuclear J-Coupling Regime. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10113836] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Chemical analysis via nuclear magnetic resonance (NMR) spectroscopy using permanent magnets, rather than superconducting magnets, is a rapidly developing field. Performing the NMR measurement in the strong heteronuclear J-coupling regime has shown considerable promise for the chemical analysis of small molecules. Typically, the condition for the strong heteronuclear J-coupling regime is satisfied at µT magnetic field strengths and enables high resolution J-coupled spectra (JCS) to be acquired. However, the JCS response to systematic chemical structural changes has largely not been investigated. In this report, we investigate the JCS of C6H6−xFx (x = 0, 1, 2, …, 6) fluorobenzene compounds via simultaneous excitation and detection of 19F and 1H at 51.5 µT. The results demonstrate that JCS are quantitative, and the common NMR observables, including Larmor frequency, heteronuclear and homonuclear J-couplings, relative signs of the J-coupling, chemical shift, and relaxation, are all measurable and are differentiable between molecules at low magnetic fields. The results, corroborated by ab initio calculations, provide new insights into the impact of chemical structure and their corresponding spin systems on JCS. In several instances, the JCS provided more chemical information than traditional high field NMR, demonstrating that JCS can be used for robust chemical analysis.
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13
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Kaseman DC, Magnelind PE, Widgeon Paisner S, Yoder JL, Alvarez M, Urbaitis AV, Janicke MT, Nath P, Espy MA, Williams RF. Design and implementation of a J-coupled spectrometer for multidimensional structure and relaxation detection at low magnetic fields. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:054103. [PMID: 32486714 DOI: 10.1063/1.5130391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 04/09/2020] [Indexed: 06/11/2023]
Abstract
In recent years, it has been realized that low and ultra-low field (mT-nT magnetic field range) nuclear magnetic resonance spectroscopy can be used for molecular structural analysis. However, spectra are often hindered by lengthy acquisition times or require large sample volumes and high concentrations. Here, we report a low field (50 μT) instrument that employs a linear actuator to shuttle samples between a 1 T prepolarization field and a solenoid detector in a laboratory setting. The current experimental setup is benchmarked using water and 13C-methanol with a single scan detection limit of 2 × 1020 spins (3 µl, 55M H2O) and detection limit of 2.9 × 1019 (200 µl, 617 mM 13C-methanol) spins with signal averaging. The system has a dynamic range of >3 orders of magnitude. Investigations of room-temperature relaxation dynamics of 13C-methanol show that sample dilution can be used in lieu of sample heating to acquire spectra with linewidths comparable to high-temperature spectra. These results indicate that the T1 and T2 mechanisms are governed by both the proton exchange rate and the dissolved oxygen in the sample. Finally, a 2D correlation spectroscopy experiment is reported, performed in the strong coupling regime that resolves the multiple resonances associated with the heteronuclear J-coupling. The spectrum was collected using 10 times less sample and in less than half the time from previous reports in the strong coupling limit.
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Affiliation(s)
- Derrick C Kaseman
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Per E Magnelind
- Quantum Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Scarlett Widgeon Paisner
- Materials Science in Radiation and Dynamics Extremes Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Jacob L Yoder
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Marc Alvarez
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Algis V Urbaitis
- Quantum Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Michael T Janicke
- Inorganic, Isotope and Actinide Chemistry Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Pulak Nath
- Quantum Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Michelle A Espy
- Non-destructive Testing and Evaluation Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Robert F Williams
- Bioenergy and Biome Sciences Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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14
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Überrück T, Adams M, Granwehr J, Blümich B. A compact X-Band ODNP spectrometer towards hyperpolarized 1H spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 314:106724. [PMID: 32278774 DOI: 10.1016/j.jmr.2020.106724] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 03/19/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
The demand for compact benchtop NMR systems that can resolve chemical shift differences in the ppm to sub-ppm range is growing. However due to material and size restrictions these magnets are limited in field strength and thus in signal intensity and quality. The implementation of standard hyperpolarization techniques is a next step in an effort to boost the signal. Here we present a compact Overhauser Dynamic Nuclear Polarization (ODNP) setup with a permanent magnet that can resolve 1H chemical shift differences in the ppm range. The assembly of the setup and its components are described in detail, and the functionality of the setup is demonstrated experimentally with ODNP enhanced relaxation measurements yielding a maximal enhancement of -140 for an aqueous 4-hydroxy-TEMPO solution. Additionally, 1H spectroscopic resolution and significant enhancements are demonstrated on acetic acid as a solvent.
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Affiliation(s)
- Till Überrück
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany
| | - Michael Adams
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany
| | - Josef Granwehr
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany; Forschungszentrum Jülich, Institut für Energie- und Klimaforschung - Grundlagen der Elektrochemie (IEK-9), 52425 Jülich, Germany
| | - Bernhard Blümich
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany.
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15
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Blümich B. Low-field and benchtop NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 306:27-35. [PMID: 31311709 DOI: 10.1016/j.jmr.2019.07.030] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/03/2019] [Accepted: 07/08/2019] [Indexed: 05/28/2023]
Abstract
NMR started at low field. Important discoveries like the first observation of NMR in condensed matter, the spin echo, NMR for chemical analysis, Fourier NMR spectroscopy, 2D NMR spectroscopy and magnetic resonance imaging happened at field strengths considered low today. With time the footprint of the NMR instruments at these field strengths shrunk from the laboratory floor to the tabletop. The first commercial tabletop NMR instruments were compact relaxometers for food analysis followed by mobile relaxometers for materials testing and oil-well exploration culminating in tabletop spectrometers for chemical analysis, capable of performing nearly the whole methodical portfolio of today's high-field instruments. The increasing sensitivity afforded by the lower noise of modern electronics and the unfolding richness of hyperpolarization scenarios along with detection schemes alternative to nuclear induction enable NMR at ultra-low field strengths down to zero applied field, where spin-spin couplings in local fields dominate the residual Zeeman interaction. Miniaturization and cost-reduction of NMR instruments outline current development goals along with the development of smart-phone-like apps to conduct standard NMR analyses.
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Affiliation(s)
- Bernhard Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Aachen, Germany.
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16
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Biller JR, Stupic KF, Moreland J. A table-top PXI based low-field spectrometer for solution dynamic nuclear polarization. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:153-163. [PMID: 29049871 DOI: 10.1002/mrc.4672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 09/29/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
We present the development of a portable dynamic nuclear polarization (DNP) instrument based on the PCI eXtensions for Instrumentation platform. The main purpose of the instrument is for study of 1 H polarization enhancements in solution through the Overhauser mechanism at low magnetic fields. A DNP probe set was constructed for use at 6.7 mT, using a modified Alderman-Grant resonator at 241 MHz for saturation of the electron transition. The solenoid for detection of the enhanced 1 H signal at 288 kHz was constructed with Litz wire. The largest observed 1 H enhancements (ε) at 6.7 mT for 14 N-CTPO radical in air saturated aqueous solution was ε~65. A concentration dependence of the enhancement is observed, with maximum ε at 5.5 mM. A low resonator efficiency for saturation of the electron paramagnetic resonance transition results in a decrease in ε for the 10.3 mM sample. At high incident powers (42 W) and long pump times, capacitor heating effects can also decrease the enhancement. The core unit and program described here could be easily adopted for multi-frequency DNP work, depending on available main magnets and selection of the "plug and play" arbitrary waveform generator, digitizer, and radiofrequency synthesizer PCI eXtensions for Instrumentatione cards.
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Affiliation(s)
- Joshua R Biller
- Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO, USA
| | - Karl F Stupic
- Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO, USA
| | - J Moreland
- Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO, USA
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17
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18
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Zhu Y, Chen CH, Wilson Z, Savukov I, Hilty C. Milli-tesla NMR and spectrophotometry of liquids hyperpolarized by dissolution dynamic nuclear polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 270:71-76. [PMID: 27423094 DOI: 10.1016/j.jmr.2016.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/18/2016] [Accepted: 06/21/2016] [Indexed: 06/06/2023]
Abstract
Hyperpolarization methods offer a unique means of improving low signal strength obtained in low-field NMR. Here, simultaneous measurements of NMR at a field of 0.7mT and laser optical absorption from samples hyperpolarized by dissolution dynamic nuclear polarization (D-DNP) are reported. The NMR measurement field closely corresponds to a typical field encountered during sample injection in a D-DNP experiment. The optical spectroscopy allows determination of the concentration of the free radical required for DNP. Correlation of radical concentration to NMR measurement of spin polarization and spin-lattice relaxation time allows determination of relaxivity and can be used for optimization of the D-DNP process. Further, the observation of the nuclear Overhauser effect originating from hyperpolarized spins is demonstrated. Signals from (1)H and (19)F in a mixture of trifluoroethanol and water are detected in a single spectrum, while different atoms of the same type are distinguished by J-coupling patterns. The resulting signal changes of individual peaks are indicative of molecular contact, suggesting a new application area of hyperpolarized low-field NMR for the determination of intermolecular interactions.
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Affiliation(s)
- Yue Zhu
- Chemistry Department, Texas A&M University, 3255 TAMU, College Station, TX 77843, USA
| | - Chia-Hsiu Chen
- Chemistry Department, Texas A&M University, 3255 TAMU, College Station, TX 77843, USA
| | - Zechariah Wilson
- Chemistry Department, Texas A&M University, 3255 TAMU, College Station, TX 77843, USA
| | - Igor Savukov
- New Mexico Consortium, 100 Entrada Drive, Los Alamos, NM 87544, USA
| | - Christian Hilty
- Chemistry Department, Texas A&M University, 3255 TAMU, College Station, TX 77843, USA.
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19
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O'Neill KT, Fridjonsson EO, Stanwix PL, Johns ML. Quantitative velocity distributions via nuclear magnetic resonance flow metering. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 269:179-185. [PMID: 27343484 DOI: 10.1016/j.jmr.2016.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 06/13/2016] [Accepted: 06/13/2016] [Indexed: 06/06/2023]
Abstract
We demonstrate the use of Tikhonov regularisation as a data inversion technique to determine the velocity distributions of flowing liquid streams. Regularisation is applied to the signal produced by a nuclear magnetic resonance (NMR) flow measurement system consisting of a pre-polarising permanent magnet located upstream of an Earth's magnetic field NMR detection coil. A simple free induction decay (FID) NMR signal is measured for the flowing stream in what is effectively a 'time-of-flight' measurement. The FID signal is then modelled as a function of fluid velocity and acquisition time, enabling determination of the velocity probability distributions via regularisation. The mean values of these velocity distributions were successfully validated against in-line rotameters. The ability to quantify multi-modal velocity distributions was also demonstrated using a two-pipe system.
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Affiliation(s)
- Keelan T O'Neill
- School of Mechanical and Chemical Engineering, University of Western Australia, Crawley, WA 6009, Australia
| | - Einar O Fridjonsson
- School of Mechanical and Chemical Engineering, University of Western Australia, Crawley, WA 6009, Australia.
| | - Paul L Stanwix
- School of Mechanical and Chemical Engineering, University of Western Australia, Crawley, WA 6009, Australia
| | - Michael L Johns
- School of Mechanical and Chemical Engineering, University of Western Australia, Crawley, WA 6009, Australia
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20
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Lee SJ, Shim JH, Kim K, Yu KK, Hwang SM. Dynamic nuclear polarization in the hyperfine-field-dominant region. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 255:114-121. [PMID: 25955437 DOI: 10.1016/j.jmr.2015.04.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/27/2015] [Accepted: 04/13/2015] [Indexed: 06/04/2023]
Abstract
Dynamic nuclear polarization (DNP) allows measuring enhanced nuclear magnetic resonance (NMR) signals. Though the efficiency of DNP has been known to increase at low fields, the usefulness of DNP has not been throughly investigated yet. Here, using a superconducting quantum interference device-based NMR system, we performed a series of DNP experiments with a nitroxide radical and measured DNP spectra at several magnetic fields down to sub-microtesla. In the DNP spectra, the large overlap of two peaks having opposite signs results in net enhancement factors, which are significantly lower than theoretical expectations and nearly invariant with respect to magnetic fields below the Earth's field. The numerical analysis based on the radical's Hamiltonian provides qualitative explanations of such features. The net enhancement factor reached 325 at maximum experimentally, but our analysis reveals that the local enhancement factor at the center of the rf coil is 575, which is unaffected by detection schemes. We conclude that DNP in the hyperfine-field-dominant region yields sufficiently enhanced NMR signals at magnetic fields above 1 μT.
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Affiliation(s)
- Seong-Joo Lee
- Center for Biosignals, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea.
| | - Jeong Hyun Shim
- Center for Biosignals, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea
| | - Kiwoong Kim
- Center for Biosignals, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea
| | - Kwon Kyu Yu
- Center for Biosignals, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea
| | - Seong-min Hwang
- Center for Biosignals, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 305-340, Republic of Korea
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21
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Neudert O, Raich HP, Mattea C, Stapf S, Münnemann K. An Alderman-Grant resonator for S-Band Dynamic Nuclear Polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2014; 242:79-85. [PMID: 24607825 DOI: 10.1016/j.jmr.2014.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 01/31/2014] [Accepted: 02/01/2014] [Indexed: 06/03/2023]
Abstract
An Alderman-Grant resonator with resonance at 2GHz (S-Band) was simulated, developed and constructed for Dynamic Nuclear Polarization (DNP) experiments at 73mT. The resonator fits into magnet bores with a minimum diameter of 20mm and is compatible with standard 3mm NMR tubes. The compact resonator design achieves good separation of electric and magnetic fields and therefore can be used with comparatively large sample volumes with only small sample heating effects comparable to those obtained with optimized X- and W-Band DNP setups. The saturation efficiency and sample heating effects were investigated for Overhauser DNP experiments of aqueous solutions of TEMPOL radical, showing relative saturation better than 0.9 and sample heating not exceeding a few Kelvin even at high microwave power and long irradiation time. An application is demonstrated, combining the DNP setup with a commercial fast field cycling NMR relaxometer. Using this resonator design at low microwave frequencies can provide DNP polarization for a class of low-field and time-domain NMR experiments and therefore may enable new applications that benefit from increased sensitivity.
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Affiliation(s)
- Oliver Neudert
- Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
| | - Hans-Peter Raich
- Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
| | - Carlos Mattea
- Institute of Physics, Ilmenau University of Technology, D-98693 Ilmenau, Germany.
| | - Siegfried Stapf
- Institute of Physics, Ilmenau University of Technology, D-98693 Ilmenau, Germany.
| | - Kerstin Münnemann
- Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
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22
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Theis T, Blanchard JW, Butler MC, Ledbetter MP, Budker D, Pines A. Chemical analysis using J-coupling multiplets in zero-field NMR. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.06.042] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Butler MC, Ledbetter MP, Theis T, Blanchard JW, Budker D, Pines A. Multiplets at zero magnetic field: The geometry of zero-field NMR. J Chem Phys 2013; 138:184202. [DOI: 10.1063/1.4803144] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Ross JG, Holland DJ, Blake A, Sederman AJ, Gladden LF. Extending the use of Earth's Field NMR using Bayesian methodology: application to particle sizing. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 222:44-52. [PMID: 22820008 DOI: 10.1016/j.jmr.2012.05.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 05/29/2012] [Accepted: 05/31/2012] [Indexed: 06/01/2023]
Abstract
There is currently much interest in extending the use of low-field magnetic resonance measurements and in particular, to obtain spatial information from these data. Here, we demonstrate the application of a Bayesian magnetic resonance approach for the sizing of objects using low magnetic field measurement technology, where there is insufficient signal-to-noise to allow a conventional imaging approach for structural characterisation. The method is illustrated in application to the sizing of spheres, in this case of radius 9.5mm, using an Earth's Field Nuclear Magnetic Resonance (EFNMR) spectrometer with pre-polarisation. Numerical simulations of the measurement at different signal-to-noise ratios and implementation of different k-space sampling schemes are considered to identify the optimal experimental protocol. In this example, the determination of sphere radius is found to be accurate to ±1mm. We confirm that the posterior distribution provides an accurate estimate of the uncertainty in the measurement.
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Affiliation(s)
- J G Ross
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke St., Cambridge CB2 3RA, UK
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25
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Theis T, Ledbetter MP, Kervern G, Blanchard JW, Ganssle PJ, Butler MC, Shin HD, Budker D, Pines A. Zero-Field NMR Enhanced by Parahydrogen in Reversible Exchange. J Am Chem Soc 2012; 134:3987-90. [DOI: 10.1021/ja2112405] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thomas Theis
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - Micah P. Ledbetter
- Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300,
United States
| | - Gwendal Kervern
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - John W. Blanchard
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - Paul J. Ganssle
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - Mark C. Butler
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - Hyun D. Shin
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
| | - Dmitry Budker
- Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300,
United States
| | - Alexander Pines
- Department
of Chemistry, University of California at Berkeley, Berkeley, California 94720-3220, United States
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26
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Gordji-Nejad A, Colell J, Glöggler S, Blümich B, Appelt S. Studies of ⁶Li-NMR properties in different salt solutions in low magnetic fields. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 214:10-14. [PMID: 22055979 DOI: 10.1016/j.jmr.2011.09.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/16/2011] [Accepted: 09/17/2011] [Indexed: 05/31/2023]
Abstract
In this article we report the longitudinal relaxation times (T(1)) of various (6)Li salts ((6)LiI, (6)LiCl and (6)LiNO(3)) in D(2)O and H(2)O, measured in low magnetic fields (B(0)=3.5mT). This investigation serves the purpose of clarifying the relaxation behavior of different (6)Li solutions and different concentrations. The measurement were undertaken to establish a framework for future applications of hyperpolarized (6)Li in medical imaging, biological studies and investigations of lithium ion batteries. Time will pass during the transport of hyperpolarized lithium ions to the sample, which leads to a polarization loss. In order to store polarization as long as possible, it is necessary to examine which (6)Li salt solution has the longest relaxation time T(1). Longitudinal relaxation times of (6)Li salts in D(2)O and H(2)O were investigated as a function of concentration and the most extended T(1) was found for (6)LiI in D(2)O and H(2)O. In agreement with the theory the relaxation time T(1) of all (6)Li salts increase with decreasing concentration. In the case of (6)LiI in H(2)O an inverse behavior was observed. We assume that the prolonged T(1) times occur due to formation of (6)LiOH upon the solution of (6)LiI in H(2)O, which settles as a precipitate. By diluting the solution, the precipitate continuously dissolves and approaches T(1) of (6)LiOH (T(1)∼28s), leading to a shorter T(1) relaxation time.
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Affiliation(s)
- A Gordji-Nejad
- Central Institute for Electronics, Research Center Jülich, D-52425 Jülich, Germany.
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Hamans BC, Andreychenko A, Heerschap A, Wijmenga SS, Tessari M. NMR at earth's magnetic field using para-hydrogen induced polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 212:224-228. [PMID: 21778094 DOI: 10.1016/j.jmr.2011.06.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 06/08/2011] [Accepted: 06/11/2011] [Indexed: 05/31/2023]
Abstract
A method to achieve NMR of dilute samples in the earth's magnetic field by applying para-hydrogen induced polarization is presented. Maximum achievable polarization enhancements were calculated by numerically simulating the experiment and compared to the experimental results and to the thermal equilibrium in the earth's magnetic field. Simultaneous 19F and 1H NMR detection on a sub-milliliter sample of a fluorinated alkyne at millimolar concentration (∼10(18) nuclear spins) was realized with just one single scan. A highly resolved spectrum with a signal/noise ratio higher than 50:1 was obtained without using an auxiliary magnet or any form of radio frequency shielding.
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Affiliation(s)
- Bob C Hamans
- Department of Radiology, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6525 GA Nijmegen, The Netherlands.
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Glöggler S, Emondts M, Colell J, Müller R, Blümich B, Appelt S. Selective drug trace detection with low-field NMR. Analyst 2011; 136:1566-8. [PMID: 21331396 DOI: 10.1039/c0an01048k] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Advances with para-hydrogen induced polarization open up new fields of applications for portable low-field NMR. Here we report the possibility of tracing drugs down to the micromolar regime. We could selectively polarize nicotine quantities similar to those found in one cigarette. Also less than 1 mg of harmine, a drug used for treatment of Parkinson's disease, and morphine extracted from an opium solution were detectable after polarization with para-hydrogen in single-scan (1)H-experiments. Moreover, we demonstrate the possibility to selectively enhance and detect the (1)H-signal of drug molecules with PHIP in proton rich standard solutions that would otherwise mask the (1)H NMR signal of the drug.
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Affiliation(s)
- Stefan Glöggler
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringer Weg 1, 52074 Aachen, Germany.
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Gong Q, Gordji-Nejad A, Blümich B, Appelt S. Trace analysis by low-field NMR: breaking the sensitivity limit. Anal Chem 2011; 82:7078-82. [PMID: 20701300 DOI: 10.1021/ac101738f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sensitivity poses a persistent challenge to NMR spectroscopy and magnetic resonance imaging (MRI). Nonhydrogenative para-hydrogen induced polarization (NH-PHIP) has recently emerged as an efficient method to substantially increase the sensitivity of high-field NMR. Here, we report the feasibility of applying NH-PHIP in the low-field NMR. A trace amount of pyridine of just a few nanoliters ( approximately 12 nmol) in a 0.4 mL NMR sample (a concentration of 31 microM or 10(16)/cm(3)) could be measured in a single scan by NH-PHIP. There is a striking difference in the signal-to-noise ratio (SNR) between thermal prepolarization and NH-PHIP: The SNR of the prepolarized (1)H NMR signal decreases linearly with decreasing (1)H concentration ([(1)H]) while the SNR in NH-PHIP experiments first increases with decreasing [(1)H], then remains constant over 2 orders of magnitude, and finally decreases linearly with decreasing [(1)H]. A hitherto unknown potential opens up for trace analysis by low-field NMR in the bio-, chemical, and material sciences.
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Affiliation(s)
- Qingxia Gong
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52056 Aachen, Germany
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Glöggler S, Müller R, Colell J, Emondts M, Dabrowski M, Blümich B, Appelt S. Para-hydrogen induced polarization of amino acids, peptides and deuterium–hydrogen gas. Phys Chem Chem Phys 2011; 13:13759-64. [DOI: 10.1039/c1cp20992b] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zotev VS, Owens T, Matlashov AN, Savukov IM, Gomez JJ, Espy MA. Microtesla MRI with dynamic nuclear polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 207:78-88. [PMID: 20843715 PMCID: PMC2956831 DOI: 10.1016/j.jmr.2010.08.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Accepted: 08/18/2010] [Indexed: 05/26/2023]
Abstract
Magnetic resonance imaging at microtesla fields is a promising imaging method that combines the pre-polarization technique and broadband signal reception by superconducting quantum interference device (SQUID) sensors to enable in vivo MRI at microtesla-range magnetic fields similar in strength to the Earth magnetic field. Despite significant advances in recent years, the potential of microtesla MRI for biomedical imaging is limited by its insufficient signal-to-noise ratio due to a relatively low sample polarization. Dynamic nuclear polarization (DNP) is a widely used approach that allows polarization enhancement by 2-4 orders of magnitude without an increase in the polarizing field strength. In this work, the first implementation of microtesla MRI with Overhauser DNP and SQUID signal detection is described. The first measurements of carbon-13 NMR spectra at microtesla fields are also reported. The experiments were performed at the measurement field of 96 μT, corresponding to Larmor frequency of 4 kHz for protons and 1 kHz for carbon-13. The Overhauser DNP was carried out at 3.5-5.7 mT fields using rf irradiation at 120 MHz. Objects for imaging included water phantoms and a cactus plant. Aqueous solutions of metabolically relevant sodium bicarbonate, pyruvate, alanine, and lactate, labeled with carbon-13, were used for NMR studies. All the samples were doped with TEMPO free radicals. The Overhauser DNP enabled nuclear polarization enhancement by factor as large as -95 for protons and as large as -200 for carbon-13, corresponding to thermal polarizations at 0.33 T and 1.1 T fields, respectively. These results demonstrate that SQUID-based microtesla MRI can be naturally combined with Overhauser DNP in one system, and that its signal-to-noise performance is greatly improved in this case. They also suggest that microtesla MRI can become an efficient tool for in vivo imaging of hyperpolarized carbon-13, produced by low-temperature dissolution DNP.
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Affiliation(s)
- Vadim S Zotev
- Los Alamos National Laboratory, Applied Modern Physics Group, MS D454, Los Alamos, NM 87545, USA.
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Lingwood MD, Ivanov IA, Cote AR, Han S. Heisenberg spin exchange effects of nitroxide radicals on Overhauser dynamic nuclear polarization in the low field limit at 1.5mT. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 204:56-63. [PMID: 20188611 DOI: 10.1016/j.jmr.2010.01.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 01/20/2010] [Accepted: 01/30/2010] [Indexed: 05/28/2023]
Abstract
Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) at very low magnetic fields (0.05-20mT) have gained interest due to the simple and portable magnet design and newly emerging applications outside of the usual laboratory setting. A method to enhance the NMR signal is needed due to the low thermal polarization of nuclear spins at these fields; dynamic nuclear polarization (DNP) via the Overhauser effect from free radicals is an attractive option. In this report we describe a DNP-enhanced NMR system operating at a fixed field of 1.5mT and measure (1)H signal enhancements of up to -350 fold during the saturation of a selected electron spin resonance (ESR) transition of dissolved nitroxide radicals. This -350 fold enhanced polarization is equivalent to what would be obtained by prepolarization in a 0.53T field. The ESR spectra at varying radical concentrations are indirectly found through DNP-enhanced NMR detection. Here, ESR line broadening at higher radical concentrations due to Heisenberg electron spin exchange is observed. Enhancements in the limit of maximum power are reported as a function of concentration for three ESR transitions, and are found to increase with concentration. The >300 fold (1)H NMR signal amplifications achievable at 1.5mT will reduce experimental time by several orders of magnitude, permitting NMR relaxation, imaging or pulsed-field gradient diffusion experiments that are inaccessible without using the DNP effect at 1.5mT. We demonstrate the potential benefit of such large signal amplification schemes through T(1) and T(2) relaxation measurements carried out in a much shorter time when employing DNP. Finally, we compare our results to those obtained in the earth's magnetic field and find that the signal to noise ratio (SNR) of DNP-enhanced signal at 1.5mT is much greater than that obtained by previous studies utilizing DNP enhancement in the 0.05mT earth's magnetic field.
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Affiliation(s)
- Mark D Lingwood
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106-9510, USA
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Garcia S, Walton JH, Armstrong B, Han S, McCarthy MJ. L-band Overhauser dynamic nuclear polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 203:138-143. [PMID: 20045658 DOI: 10.1016/j.jmr.2009.12.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2009] [Revised: 12/09/2009] [Accepted: 12/11/2009] [Indexed: 05/28/2023]
Abstract
We present the development of an Overhauser dynamic nuclear polarization (DNP) instrument at 0.04 T using 1.1 GHz (L-band) electron spin resonance frequencies (ESR) and 1.7 MHz (1)H nuclear magnetic resonance frequencies. Using this home-built DNP system, the electron-nucleus coupling factor of 4-oxo-TEMPO dissolved in water was determined as 0.39+/-0.06 at 0.04 T. The higher coupling factor obtained at this field compared to higher magnetic fields, such as 0.35 T, directly translates to higher enhancement of the NMR signal and opens up a wider time scale window for observing water dynamics interacting with macromolecular systems, including proteins, polymers or lipid vesicles. The higher enhancements obtained will facilitate the observation of water dynamics at correlation times up to 10 ns, that corresponds to more than one order of magnitude slower dynamics than accessible at 0.35 T using X-band ESR frequencies.
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Affiliation(s)
- Sandra Garcia
- Department of Food Science & Technology, University of California, Davis, CA 95616, USA.
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