1
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Salnikov OG, Assaf CD, Yi AP, Duckett SB, Chekmenev EY, Hövener JB, Koptyug IV, Pravdivtsev AN. Modeling Ligand Exchange Kinetics in Iridium Complexes Catalyzing SABRE Nuclear Spin Hyperpolarization. Anal Chem 2024; 96:11790-11799. [PMID: 38976810 PMCID: PMC11270526 DOI: 10.1021/acs.analchem.4c01374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/29/2024] [Accepted: 06/18/2024] [Indexed: 07/10/2024]
Abstract
Large signal enhancements can be obtained for NMR analytes using the process of nuclear spin hyperpolarization. Organometallic complexes that bind parahydrogen can themselves become hyperpolarized. Moreover, if parahydrogen and a to-be-hyperpolarized analyte undergo chemical exchange with the organometallic complex it is possible to catalytically sensitize the detection of the analyte via hyperpolarization transfer through spin-spin coupling in this organometallic complex. This process is called Signal Amplification By Reversible Exchange (SABRE). Signal intensity gains of several orders of magnitude can thus be created for various compounds in seconds. The chemical exchange processes play a defining role in controlling the efficiency of SABRE because the lifetime of the complex must match the spin-spin couplings. Here, we show how analyte dissociation rates in the key model substrates pyridine (the simplest six-membered heterocycle), 4-aminopyridine (a drug), and nicotinamide (an essential vitamin biomolecule) can be examined. This is achieved for the most widely employed SABRE motif that is based on IrIMes-derived catalysts by 1H 1D and 2D exchange NMR spectroscopy techniques. Several kinetic models are evaluated for their accuracy and simplicity. By incorporating variable temperature analysis, the data yields key enthalpies and entropies of activation that are critical for understanding the underlying SABRE catalyst properties and subsequently optimizing behavior through rational chemical design. While several studies of chemical exchange in SABRE have been reported, this work also aims to establish a toolkit on how to quantify chemical exchange in SABRE and ensure that data can be compared reliably.
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Affiliation(s)
- Oleg G. Salnikov
- International
Tomography Center SB RAS, 3A Institutskaya St., 630090 Novosibirsk, Russia
| | - Charbel D. Assaf
- Section
Biomedical Imaging, Molecular Imaging North Competence Center (MOIN
CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Am Botanischen Garten 14, 24118 Kiel, Germany
| | - Anna P. Yi
- International
Tomography Center SB RAS, 3A Institutskaya St., 630090 Novosibirsk, Russia
- Novosibirsk
State University, 2 Pirogova
St., 630090 Novosibirsk, Russia
| | - Simon B. Duckett
- Centre
for Hyperpolarization in Magnetic Resonance (CHyM), University of York, Heslington YO10 5NY, U.K.
| | - Eduard Y. Chekmenev
- Department
of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute
(KCI), Wayne State University, Detroit, Michigan 48202, United States
| | - Jan-Bernd Hövener
- Section
Biomedical Imaging, Molecular Imaging North Competence Center (MOIN
CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Am Botanischen Garten 14, 24118 Kiel, Germany
| | - Igor V. Koptyug
- International
Tomography Center SB RAS, 3A Institutskaya St., 630090 Novosibirsk, Russia
| | - Andrey N. Pravdivtsev
- Section
Biomedical Imaging, Molecular Imaging North Competence Center (MOIN
CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Am Botanischen Garten 14, 24118 Kiel, Germany
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2
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Barskiy DA. Molecules, Up Your Spins! Molecules 2024; 29:1821. [PMID: 38675641 PMCID: PMC11052189 DOI: 10.3390/molecules29081821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) are indispensable tools in science and medicine, offering insights into the functions of biological processes [...].
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Affiliation(s)
- Danila A. Barskiy
- Institut für Physik, Johannes-Gutenberg-Universität Mainz, 55128 Mainz, Germany;
- Helmholtz Institut Mainz, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
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3
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Luu QS, Nguyen QT, Manh HN, Yun S, Kim J, Do UT, Jeong K, Lee SU, Lee Y. SABRE hyperpolarization of nicotinamide derivatives and their molecular dynamics properties. Analyst 2024; 149:1068-1073. [PMID: 38265242 DOI: 10.1039/d3an02053c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Signal amplification by reversible exchange hyperpolarization explores the chemical structure and kinetic properties of nicotinamide derivatives. N-Benzyl nicotinamide and nicotinic acid hydrazide compounds display relatively fast dissociation rates of approximately 7-8 s-1 and long proton T1 relaxation times of 5-20 s, respectively. Consequently, these substrates exhibit remarkable signal enhancements, reaching approximately 175 and 102 fold, respectively, underscoring the efficacy of the hyperpolarization technique in elucidating the behavior of these compounds.
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Affiliation(s)
- Quy Son Luu
- Department of Bionano Technology, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 15588, South Korea.
| | - Quynh Thi Nguyen
- Department of Applied Chemistry, Hanyang University, Ansan 15588, South Korea
| | - Hung Ngo Manh
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16149, South Korea.
| | - Seokki Yun
- Department of Applied Chemistry, Hanyang University, Ansan 15588, South Korea
| | - Jiwon Kim
- Department of Bionano Technology, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 15588, South Korea.
| | - Uyen Thi Do
- Department of Bionano Technology, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 15588, South Korea.
| | - Keunhong Jeong
- Department of Chemistry, Korea Military Academy, Seoul, 01805, South Korea.
| | - Sang Uck Lee
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16149, South Korea.
| | - Youngbok Lee
- Department of Bionano Technology, Center for Bionano Intelligence Education and Research, Hanyang University, Ansan 15588, South Korea.
- Department of Applied Chemistry, Hanyang University, Ansan 15588, South Korea
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4
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Parker AJ, Dey A, Usman Qureshi M, Steiner JM, Blanchard JW, Scheuer J, Tomek N, Knecht S, Josten F, Müller C, Hautle P, Schwartz I, Giraudeau P, Eichhorn TR, Dumez JN. Solution-State 2D NMR Spectroscopy of Mixtures HyperpolarizedUsing Optically Polarized Crystals. Angew Chem Int Ed Engl 2023; 62:e202312302. [PMID: 37837321 DOI: 10.1002/anie.202312302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/30/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
The HYPNOESYS method (Hyperpolarized NOE System), which relies on the dissolution of optically polarized crystals, has recently emerged as a promising approach to enhance the sensitivity of NMR spectroscopy in the solution state. However, HYPNOESYS is a single-shot method that is not generally compatible with multidimensional NMR. Here we show that 2D NMR spectra can be obtained from HYPNOESYS-polarized samples, using single-scan acquisition methods. The approach is illustrated with a mixture of terpene molecules and a benchtop NMR spectrometer, paving the way to a sensitive, information-rich and affordable analytical method.
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Affiliation(s)
- Anna J Parker
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Arnab Dey
- Nantes Université, CNRS, CEISAM UMR6230, 44000, Nantes, France
| | | | - Jakob M Steiner
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
- Paul Scherrer Insititute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - John W Blanchard
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Jochen Scheuer
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Nikolas Tomek
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Stephan Knecht
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Felix Josten
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Christoph Müller
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | - Patrick Hautle
- Paul Scherrer Insititute, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Ilai Schwartz
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
| | | | - Tim R Eichhorn
- NVision Imaging Technologies GmbH, Wolfgang-Paul-Strasse 2, 89081, Ulm, Germany
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5
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Jagtap AP, Mamone S, Glöggler S. Molecular precursors to produce para-hydrogen enhanced metabolites at any field. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:674-680. [PMID: 37821237 DOI: 10.1002/mrc.5402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 09/12/2023] [Accepted: 09/18/2023] [Indexed: 10/13/2023]
Abstract
Enhancing magnetic resonance signal via hyperpolarization techniques enables the real-time detection of metabolic transformations even in vivo. The use of para-hydrogen to enhance 13 C-enriched metabolites has opened a rapid pathway for the production of hyperpolarized metabolites, which usually requires specialized equipment. Metabolite precursors that can be hyperpolarized and converted into metabolites at any given field would open up opportunities for many labs to make use of this technology because already existing hardware could be used. We report here on the complete synthesis and hyperpolarization of suitable precursor molecules of the side-arm hydrogenation approach. The better accessibility to such side-arms promises that the para-hydrogen approach can be implemented in every lab with existing two channel NMR spectrometers for 1 H and 13 C independent of the magnetic field.
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Affiliation(s)
- Anil P Jagtap
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration, University Medicine Göttingen, Göttingen, Germany
| | - Salvatore Mamone
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration, University Medicine Göttingen, Göttingen, Germany
| | - Stefan Glöggler
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration, University Medicine Göttingen, Göttingen, Germany
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6
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Dey A, Charrier B, Ribay V, Dumez JN, Giraudeau P. Hyperpolarized 1H and 13C NMR Spectroscopy in a Single Experiment for Metabolomics. Anal Chem 2023; 95:16861-16867. [PMID: 37947414 DOI: 10.1021/acs.analchem.3c02614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The application of NMR spectroscopy to complex mixture analysis and, in particular, to metabolomics is limited by the low sensitivity of NMR. We recently showed that dissolution dynamic nuclear polarization (d-DNP) could enhance the sensitivity of 13C NMR for complex metabolite mixtures, leading to the detection of highly sensitive 13C NMR fingerprints of complex samples such as plant extracts or urine. While such experiments provide heteronuclear spectra, which are complementary to conventional NMR, hyperpolarized 1H NMR spectra would also be highly useful, with improved limits of detection and compatibility with the existing metabolomics workflow and databases. In this technical note, we introduce an approach capable of recording both 1H and 13C hyperpolarized spectra of metabolite mixtures in a single experiment and on the same hyperpolarized sample. We investigate the analytical performance of this method in terms of sensitivity and repeatability, and then we show that it can be efficiently applied to a plant extract. Significant sensitivity enhancements in 1H NMR are reported with a repeatability suitable for metabolomics studies without compromising on the performance of hyperpolarized 13C NMR. This approach provides a way to perform both 1H and 13C hyperpolarized NMR metabolomics with unprecedented sensitivity and throughput.
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Affiliation(s)
- Arnab Dey
- Nantes Université, CEISAM UMR 6230, 44000 Nantes, France
| | | | - Victor Ribay
- Nantes Université, CEISAM UMR 6230, 44000 Nantes, France
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7
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Zheng Z, Liu M, Wang X, Jiang W, Peng Q, Sun H, Chen Z. The experimental approach for the interleaved joint modulation of PHIP and NMR. J Chem Phys 2023; 159:184201. [PMID: 37937935 DOI: 10.1063/5.0173895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 10/18/2023] [Indexed: 11/09/2023] Open
Abstract
Nuclear spin hyperpolarization derived from parahydrogen is a technique for enhancing nuclear magnetic resonance (NMR) sensitivity. The key to hyperpolarization experiments is to achieve rapid transfer and detection to minimize relaxation losses, while also avoiding bubbles or turbulence to guarantee high spectral resolution. In this article, we describe an experimental approach for the interleaved joint modulation of parahydrogen-induced polarization and NMR. We provide schematic diagrams of parahydrogen-based polarizer with in situ high-pressure detection capability and low-field polarization transfer. This approach can help to control the experimental process and acquire experimental information, one example of which is the attainment of the highest hyperpolarization signal intensity at 3.6 s after closing the valve. The polarizer demonstrates in situ detection capability, allowing sample to be restabilized within 0.3 ± 0.1 s and high-resolution NMR sampling under a pressure of 3 bars. Moreover, it can transfer polarized samples from the polarization transfer field to the detection region of NMR within 1 ± 0.3 s for completing signal amplification by reversible exchange experiments.
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Affiliation(s)
- Zeyu Zheng
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
| | - Min Liu
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
| | - Xinchang Wang
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, 361005 Xiamen, China
| | - Wenlong Jiang
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
| | - Qiwei Peng
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
| | - Huijun Sun
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
| | - Zhong Chen
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Department of Electronic Science, Xiamen University, 361005 Xiamen, China
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, 361005 Xiamen, China
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8
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Ghini V, Meoni G, Vignoli A, Di Cesare F, Tenori L, Turano P, Luchinat C. Fingerprinting and profiling in metabolomics of biosamples. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2023; 138-139:105-135. [PMID: 38065666 DOI: 10.1016/j.pnmrs.2023.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 12/18/2023]
Abstract
This review focuses on metabolomics from an NMR point of view. It attempts to cover the broad scope of metabolomics and describes the NMR experiments that are most suitable for each sample type. It is addressed not only to NMR specialists, but to all researchers who wish to approach metabolomics with a clear idea of what they wish to achieve but not necessarily with a deep knowledge of NMR. For this reason, some technical parts may seem a bit naïve to the experts. The review starts by describing standard metabolomics procedures, which imply the use of a dedicated 600 MHz instrument and of four properly standardized 1D experiments. Standardization is a must if one wants to directly compare NMR results obtained in different labs. A brief mention is also made of standardized pre-analytical procedures, which are even more essential. Attention is paid to the distinction between fingerprinting and profiling, and the advantages and disadvantages of fingerprinting are clarified. This aspect is often not fully appreciated. Then profiling, and the associated problems of signal assignment and quantitation, are discussed. We also describe less conventional approaches, such as the use of different magnetic fields, the use of signal enhancement techniques to increase sensitivity, and the potential of field-shuttling NMR. A few examples of biomedical applications are also given, again with the focus on NMR techniques that are most suitable to achieve each particular goal, including a description of the most common heteronuclear experiments. Finally, the growing applications of metabolomics to foodstuffs are described.
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Affiliation(s)
- Veronica Ghini
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy
| | - Gaia Meoni
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy
| | - Alessia Vignoli
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy
| | - Francesca Di Cesare
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy
| | - Leonardo Tenori
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, Italy
| | - Paola Turano
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, Italy.
| | - Claudio Luchinat
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, Italy; Giotto Biotech S.r.l., Sesto Fiorentino, Italy.
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9
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Min S, Baek J, Kim J, Jeong HJ, Chung J, Jeong K. Water-Compatible and Recyclable Heterogeneous SABRE Catalyst for NMR Signal Amplification. JACS AU 2023; 3:2912-2917. [PMID: 37885596 PMCID: PMC10598823 DOI: 10.1021/jacsau.3c00487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/28/2023]
Abstract
A water-compatible and recyclable catalyst for nuclear magnetic resonance (NMR) hyperpolarization via signal amplification by reversible exchange (SABRE) was developed. The [Ir(COD)(IMes)Cl] catalyst was attached to a polymeric resin of bis(2-pyridyl)amine (heterogeneous SABRE catalyst, HET-SABRE catalyst), and it amplified the 1H NMR signal of pyridine up to (-) 4455-fold (43.2%) at 1.4 T in methanol and (-) 50-fold (0.5%) in water. These are the highest amplification factors ever reported among HET-SABRE catalysts and for the first time in aqueous media. Moreover, the HET-SABRE catalyst demonstrated recyclability by retaining its activity in water after more than three uses. This newly designed polymeric resin-based heterogeneous catalyst shows great promise for NMR signal amplification for biomedical NMR and MRI applications in the future.
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Affiliation(s)
- Sein Min
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Juhee Baek
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Jisu Kim
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Hye Jin Jeong
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Jean Chung
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Keunhong Jeong
- Department
of Chemistry, Korea Military Academy, Seoul 01805, South Korea
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10
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Alshehri A, Tickner BJ, Iali W, Duckett SB. Enhancing the NMR signals of plant oil components using hyperpolarisation relayed via proton exchange. Chem Sci 2023; 14:9843-9853. [PMID: 37736655 PMCID: PMC10510812 DOI: 10.1039/d3sc03078d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/25/2023] [Indexed: 09/23/2023] Open
Abstract
In this work, the limited sensitivity of magnetic resonance is addressed by using the hyperpolarisation method relayed signal amplification by reversible exchange (SABRE-Relay) to transfer latent magnetism from para-hydrogen, a readily isolated spin isomer of hydrogen gas, to components of key plant oils such as citronellol, geraniol, and nerol. This is achieved via relayed polarisation transfer in which an [Ir(H)2(IMes)(NH2R)3]Cl type complex produces hyperpolarised NH2R free in solution, before labile proton exchange between the hyperpolarisation carrier (NH2R) and the OH-containing plant oil component generates enhanced NMR signals for the latter. Consequently, up to ca. 200-fold 1H (0.65% 1H polarisation) and 800-fold 13C NMR signal enhancements (0.65% 13C polarisation) are recorded for these essential oils in seconds. Remarkably, the resulting NMR signals are not only diagnostic, but prove to propagate over large spin systems via a suitable coupling network. A route to optimise the enhancement process by varying the identity of the carrier NH2R, and its concentration is demonstrated. In order to prove utility, these pilot measurements are extended to study a much wider range of plant-derived molecules including rhodinol, verbenol, (1R)-endo-(+)-fenchyl alcohol, (-)-carveol, and linalool. Further measurements are then described which demonstrate citronellol and geraniol can be detected in an off-the-shelf healthcare product rose geranium oil at concentrations of just a few tens of μM in single scan 1H NMR measurements, which are not visible in comparable thermally polarised NMR experiments. This work therefore presents a significant expansion of the types of molecules amenable to hyperpolarisation using para-hydrogen and illustrates a real-world application in the diagnostic detection of low concentration analytes in mixtures.
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Affiliation(s)
- Adel Alshehri
- Department of Chemistry, Centre for Hyperpolarisation in Magnetic Resonance, University of York Heslington YO10 5NY UK
| | - Ben J Tickner
- Department of Chemistry, Centre for Hyperpolarisation in Magnetic Resonance, University of York Heslington YO10 5NY UK
| | - Wissam Iali
- Department of Chemistry, Centre for Hyperpolarisation in Magnetic Resonance, University of York Heslington YO10 5NY UK
| | - Simon B Duckett
- Department of Chemistry, Centre for Hyperpolarisation in Magnetic Resonance, University of York Heslington YO10 5NY UK
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11
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Ribay V, Praud C, Letertre MPM, Dumez JN, Giraudeau P. Hyperpolarized NMR metabolomics. Curr Opin Chem Biol 2023; 74:102307. [PMID: 37094508 DOI: 10.1016/j.cbpa.2023.102307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/20/2023] [Accepted: 03/21/2023] [Indexed: 04/26/2023]
Abstract
Hyperpolarized NMR is a promising approach to address the sensitivity limits of conventional NMR metabolomics approaches, which currently fails to detect minute metabolite concentrations in biological samples. This review describes how tremendous signal enhancement offered by dissolution-dynamic nuclear polarization and parahydrogen-based techniques can be fully exploited for molecular omics sciences. Recent developments, including the combination of hyperpolarization techniques with fast multi-dimensional NMR implementation and quantitative workflows are described, and a comprehensive comparison of existing hyperpolarization techniques is proposed. High-throughput, sensitivity, resolution and other relevant challenges that should be tackled for a general application of hyperpolarized NMR in metabolomics are discussed.
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Affiliation(s)
- Victor Ribay
- Nantes Université, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
| | - Clément Praud
- Nantes Université, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
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12
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Jeong HJ, Min S, Baek J, Kim J, Chung J, Jeong K. Real-Time Reaction Monitoring of Azide-Alkyne Cycloadditions Using Benchtop NMR-Based Signal Amplification by Reversible Exchange (SABRE). ACS MEASUREMENT SCIENCE AU 2023; 3:134-142. [PMID: 37090259 PMCID: PMC10120034 DOI: 10.1021/acsmeasuresciau.2c00065] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/30/2022] [Accepted: 01/03/2023] [Indexed: 05/03/2023]
Abstract
Rufinamide, possessing a triazole ring, is a new antiepileptic drug (AED) relatively well-absorbed in the lower dose range (10 mg/kg per day) and is currently being used in antiepileptic medications. Triazole derivatives can interact with various enzymes and receptors in biological systems via diverse non-covalent interactions, thus inducing versatile biological effects. Strain-promoted azide-alkyne cycloaddition (SPAAC) is a significant method for obtaining triazoles, even under physiological conditions, in the absence of a copper catalyst. To confirm the progress of chemical reactions under biological conditions, research on reaction monitoring at low concentrations is essential. This promising strategy is gaining acceptance for applications in fields such as drug development and nanoscience. We investigated the optimum Ir catalyst and magnetic field for achieving maximum proton hyperpolarization transfer in triazole derivatives. These reactions were analyzed using signal amplification by reversible exchange (SABRE) to overcome the limitations of low sensitivity in nuclear magnetic resonance spectroscopy, when monitoring copper-free click reactions in real time. Finally, a more versatile copper-catalyzed click reaction was monitored in real time, using a 60 MHz benchtop NMR system, in order to analyze the reaction mechanism.
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Affiliation(s)
- Hye Jin Jeong
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Sein Min
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Juhee Baek
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Jisu Kim
- Department
of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Jean Chung
- Department
of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Keunhong Jeong
- Department
of Physics and Chemistry, Korea Military
Academy, Seoul 01805, South Korea
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13
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Ellermann F, Saul P, Hövener JB, Pravdivtsev AN. Modern Manufacturing Enables Magnetic Field Cycling Experiments and Parahydrogen-Induced Hyperpolarization with a Benchtop NMR. Anal Chem 2023; 95:6244-6252. [PMID: 37018544 DOI: 10.1021/acs.analchem.2c03682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Benchtop NMR (btNMR) spectrometers are revolutionizing the way we use NMR and lowering the cost drastically. Magnetic field cycling (MFC) experiments with precise timing and control over the magnetic field, however, were hitherto not available on btNMRs, although some systems exist for high-field, high-resolution NMR spectrometers. Still, the need and potential for btNMR MFC is great─e.g., to perform and analyze parahydrogen-induced hyperpolarization, another method that has affected analytical chemistry and NMR beyond expectations. Here, we describe a setup that enables MFC on btNMRs for chemical analysis and hyperpolarization. Taking full advantage of the power of modern manufacturing, including computer-aided design, three-dimensional printing, and microcontrollers, the setup is easy to reproduce, highly reliable, and easy to adjust and operate. Within 380 ms, the NMR tube was shuttled reliably from the electromagnet to the NMR isocenter (using a stepper motor and gear rod). We demonstrated the power of this setup by hyperpolarizing nicotinamide using signal amplification by reversible exchange (SABRE), a versatile method to hyperpolarize a broad variety of molecules including metabolites and drugs. Here, the standard deviation of SABRE hyperpolarization was between 0.2 and 3.3%. The setup also allowed us to investigate the field dependency of the polarization and the effect of different sample preparation protocols. We found that redissolution of the activated and dried Ir catalyst always reduced the polarization. We anticipate that this design will greatly accelerate the ascension of MFC experiments for chemical analysis with btNMR─adding yet another application to this rapidly developing field.
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Affiliation(s)
- Frowin Ellermann
- Section for Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel 24118, Germany
| | - Philip Saul
- Section for Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel 24118, Germany
| | - Jan-Bernd Hövener
- Section for Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel 24118, Germany
| | - Andrey N Pravdivtsev
- Section for Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel 24118, Germany
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14
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Eills J, Budker D, Cavagnero S, Chekmenev EY, Elliott SJ, Jannin S, Lesage A, Matysik J, Meersmann T, Prisner T, Reimer JA, Yang H, Koptyug IV. Spin Hyperpolarization in Modern Magnetic Resonance. Chem Rev 2023; 123:1417-1551. [PMID: 36701528 PMCID: PMC9951229 DOI: 10.1021/acs.chemrev.2c00534] [Citation(s) in RCA: 64] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Indexed: 01/27/2023]
Abstract
Magnetic resonance techniques are successfully utilized in a broad range of scientific disciplines and in various practical applications, with medical magnetic resonance imaging being the most widely known example. Currently, both fundamental and applied magnetic resonance are enjoying a major boost owing to the rapidly developing field of spin hyperpolarization. Hyperpolarization techniques are able to enhance signal intensities in magnetic resonance by several orders of magnitude, and thus to largely overcome its major disadvantage of relatively low sensitivity. This provides new impetus for existing applications of magnetic resonance and opens the gates to exciting new possibilities. In this review, we provide a unified picture of the many methods and techniques that fall under the umbrella term "hyperpolarization" but are currently seldom perceived as integral parts of the same field. Specifically, before delving into the individual techniques, we provide a detailed analysis of the underlying principles of spin hyperpolarization. We attempt to uncover and classify the origins of hyperpolarization, to establish its sources and the specific mechanisms that enable the flow of polarization from a source to the target spins. We then give a more detailed analysis of individual hyperpolarization techniques: the mechanisms by which they work, fundamental and technical requirements, characteristic applications, unresolved issues, and possible future directions. We are seeing a continuous growth of activity in the field of spin hyperpolarization, and we expect the field to flourish as new and improved hyperpolarization techniques are implemented. Some key areas for development are in prolonging polarization lifetimes, making hyperpolarization techniques more generally applicable to chemical/biological systems, reducing the technical and equipment requirements, and creating more efficient excitation and detection schemes. We hope this review will facilitate the sharing of knowledge between subfields within the broad topic of hyperpolarization, to help overcome existing challenges in magnetic resonance and enable novel applications.
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Affiliation(s)
- James Eills
- Institute
for Bioengineering of Catalonia, Barcelona
Institute of Science and Technology, 08028Barcelona, Spain
| | - Dmitry Budker
- Johannes
Gutenberg-Universität Mainz, 55128Mainz, Germany
- Helmholtz-Institut,
GSI Helmholtzzentrum für Schwerionenforschung, 55128Mainz, Germany
- Department
of Physics, UC Berkeley, Berkeley, California94720, United States
| | - Silvia Cavagnero
- Department
of Chemistry, University of Wisconsin, Madison, Madison, Wisconsin53706, United States
| | - Eduard Y. Chekmenev
- Department
of Chemistry, Integrative Biosciences (IBio), Karmanos Cancer Institute
(KCI), Wayne State University, Detroit, Michigan48202, United States
- Russian
Academy of Sciences, Moscow119991, Russia
| | - Stuart J. Elliott
- Molecular
Sciences Research Hub, Imperial College
London, LondonW12 0BZ, United Kingdom
| | - Sami Jannin
- Centre
de RMN à Hauts Champs de Lyon, Université
de Lyon, CNRS, ENS Lyon, Université Lyon 1, 69100Villeurbanne, France
| | - Anne Lesage
- Centre
de RMN à Hauts Champs de Lyon, Université
de Lyon, CNRS, ENS Lyon, Université Lyon 1, 69100Villeurbanne, France
| | - Jörg Matysik
- Institut
für Analytische Chemie, Universität
Leipzig, Linnéstr. 3, 04103Leipzig, Germany
| | - Thomas Meersmann
- Sir
Peter Mansfield Imaging Centre, University Park, School of Medicine, University of Nottingham, NottinghamNG7 2RD, United Kingdom
| | - Thomas Prisner
- Institute
of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic
Resonance, Goethe University Frankfurt, , 60438Frankfurt
am Main, Germany
| | - Jeffrey A. Reimer
- Department
of Chemical and Biomolecular Engineering, UC Berkeley, and Materials Science Division, Lawrence Berkeley National
Laboratory, Berkeley, California94720, United States
| | - Hanming Yang
- Department
of Chemistry, University of Wisconsin, Madison, Madison, Wisconsin53706, United States
| | - Igor V. Koptyug
- International Tomography Center, Siberian
Branch of the Russian Academy
of Sciences, 630090Novosibirsk, Russia
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15
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Silva Terra AI, Rossetto M, Dickson CL, Peat G, Uhrín D, Halse ME. Enhancing 19F Benchtop NMR Spectroscopy by Combining para-Hydrogen Hyperpolarization and Multiplet Refocusing. ACS MEASUREMENT SCIENCE AU 2023; 3:73-81. [PMID: 36817010 PMCID: PMC9936801 DOI: 10.1021/acsmeasuresciau.2c00055] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 06/18/2023]
Abstract
Benchtop NMR spectrometers provide a promising alternative to high-field NMR for applications that are limited by instrument size and/or cost. 19F benchtop NMR is attractive due to the larger chemical shift range of 19F relative to 1H and the lack of background signal in most applications. However, practical applications of benchtop 19F NMR are limited by its low sensitivity due to the relatively weak field strengths of benchtop NMR spectrometers. Here we present a sensitivity-enhancement strategy that combines SABRE (Signal Amplification By Reversible Exchange) hyperpolarization with the multiplet refocusing method SHARPER (Sensitive, Homogeneous, And Resolved PEaks in Real time). When applied to a range of fluoropyridines, SABRE-SHARPER achieves overall signal enhancements of up to 5700-fold through the combined effects of hyperpolarization and line-narrowing. This approach can be generalized to the analysis of mixtures through the use of a selective variant of the SHARPER sequence, selSHARPER. The ability of SABRE-selSHARPER to simultaneously boost sensitivity and discriminate between two components of a mixture is demonstrated, where selectivity is achieved through a combination of selective excitation and the choice of polarization transfer field during the SABRE step.
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Affiliation(s)
| | | | - Claire L. Dickson
- EaStCHEM
School of Chemistry, University of Edinburgh, EdinburghEH9 3FJ, U.K.
| | - George Peat
- EaStCHEM
School of Chemistry, University of Edinburgh, EdinburghEH9 3FJ, U.K.
| | - Dušan Uhrín
- EaStCHEM
School of Chemistry, University of Edinburgh, EdinburghEH9 3FJ, U.K.
| | - Meghan E. Halse
- Department
of Chemistry, University of York, YorkYO10 5DD, U.K.
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16
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Duchowny A, Denninger J, Lohmann L, Theis T, Lehmkuhl S, Adams A. SABRE Hyperpolarization with up to 200 bar Parahydrogen in Standard and Quickly Removable Solvents. Int J Mol Sci 2023; 24:2465. [PMID: 36768786 PMCID: PMC9917027 DOI: 10.3390/ijms24032465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/31/2023] Open
Abstract
Parahydrogen (p-H2)-based techniques are known to drastically enhance NMR signals but are usually limited by p-H2 supply. This work reports p-H2-based SABRE hyperpolarization at p-H2 pressures of hundreds of bar, far beyond the typical ten bar currently reported in the literature. A recently designed high-pressure setup was utilized to compress p-H2 gas up to 200 bar. The measurements were conducted using a sapphire high-pressure NMR tube and a 43 MHz benchtop NMR spectrometer. In standard methanol solutions, it could be shown that the signal intensities increased with pressure until they eventually reached a plateau. A polarization of about 2%, equal to a molar polarization of 1.2 mmol L-1, could be achieved for the sample with the highest substrate concentration. While the signal plateaued, the H2 solubility increased linearly with pressure from 1 to 200 bar, indicating that p-H2 availability is not the limiting factor in signal enhancement beyond a certain pressure, depending on sample composition. Furthermore, the possibility of using liquefied ethane and compressed CO2 as removable solvents for hyperpolarization was demonstrated. The use of high pressures together with quickly removable organic/non-organic solvents represents an important breakthrough in the field of hyperpolarization, advancing SABRE as a promising tool for materials science, biophysics, and molecular imaging.
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Affiliation(s)
- Anton Duchowny
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, 52074 Aachen, Germany
| | - Johannes Denninger
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, 52074 Aachen, Germany
| | - Lars Lohmann
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, 52074 Aachen, Germany
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Sören Lehmkuhl
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Alina Adams
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, 52074 Aachen, Germany
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17
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Hune T, Mamone S, Schroeder H, Jagtap AP, Sternkopf S, Stevanato G, Korchak S, Fokken C, Müller CA, Schmidt AB, Becker D, Glöggler S. Metabolic Tumor Imaging with Rapidly Signal-Enhanced 1- 13 C-Pyruvate-d 3. Chemphyschem 2023; 24:e202200615. [PMID: 36106366 PMCID: PMC10092681 DOI: 10.1002/cphc.202200615] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/14/2022] [Indexed: 01/20/2023]
Abstract
The metabolism of malignant cells differs significantly from that of healthy cells and thus, it is possible to perform metabolic imaging to reveal not only the exact location of a tumor, but also intratumoral areas of high metabolic activity. Herein, we demonstrate the feasibility of metabolic tumor imaging using signal-enhanced 1-13 C-pyruvate-d3 , which is rapidly enhanced via para-hydrogen, and thus, the signal is amplified by several orders of magnitudes in less than a minute. Using as a model, human melanoma xenografts injected with signal-enhanced 1-13 C-pyruvate-d3, we show that the conversion of pyruvate into lactate can be monitored along with its kinetics, which could pave the way for rapidly detecting and monitoring changes in tumor metabolism.
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Affiliation(s)
- Theresa Hune
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Salvatore Mamone
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Henning Schroeder
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Anil P Jagtap
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Sonja Sternkopf
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Gabriele Stevanato
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Sergey Korchak
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
| | - Claudia Fokken
- Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany
| | - Christoph A Müller
- German Cancer Consortium (DKTK), partner site Freiburg, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany.,Division of Medical Physics, Department of Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), partner site Freiburg, Killianstr. 5a, Freiburg, 79106, Germany
| | - Andreas B Schmidt
- German Cancer Consortium (DKTK), partner site Freiburg, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany.,Division of Medical Physics, Department of Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, German Cancer Consortium (DKTK), partner site Freiburg, Killianstr. 5a, Freiburg, 79106, Germany.,Integrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, 48202, Detroit, MI, USA
| | - Dorothea Becker
- Department of NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany
| | - Stefan Glöggler
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration of the University Medical Center Göttingen, Von-Siebold-Str. 3A, 37075, Göttigen, Germany
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18
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Dreisewerd L, Aspers RLEG, Feiters MC, Rutjes FPJT, Tessari M. NMR Discrimination of d- and l-α-Amino Acids at Submicromolar Concentration via Parahydrogen-Induced Hyperpolarization. J Am Chem Soc 2023; 145:1518-1523. [PMID: 36626573 PMCID: PMC9880991 DOI: 10.1021/jacs.2c11285] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Differentiation of enantiomers represents an important research area for pharmaceutical, chemical, and food industries. However, enantiomer separation is a laborious task that demands complex analytical techniques, specialized equipment, and expert personnel. In this respect, discrimination and quantification of d- and l-α-amino acids is no exception, generally requiring extensive sample manipulation, including isolation, functionalization, and chiral separation. This complex sample treatment results in high time costs and potential biases in the quantitative determination. Here, we present an approach based on the combination of non-hydrogenative parahydrogen-induced hyperpolarization and nuclear magnetic resonance that allows detection, discrimination, and quantification of d- and l-α-amino acids in complex mixtures such as biofluids and food extracts down to submicromolar concentrations. Importantly, this method can be directly applied to the system under investigation without any prior isolation, fractionation, or functionalization step.
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19
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Dumez JN. NMR methods for the analysis of mixtures. Chem Commun (Camb) 2022; 58:13855-13872. [PMID: 36458684 PMCID: PMC9753098 DOI: 10.1039/d2cc05053f] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 10/19/2022] [Indexed: 07/31/2023]
Abstract
NMR spectroscopy is a powerful approach for the analysis of mixtures. Its usefulness arises in large part from the vast landscape of methods, and corresponding pulse sequences, that have been and are being designed to tackle the specific properties of mixtures of small molecules. This feature article describes a selection of methods that aim to address the complexity, the low concentrations, and the changing nature that mixtures can display. These notably include pure-shift and diffusion NMR methods, hyperpolarisation methods, and fast 2D NMR methods such as ultrafast 2D NMR and non-uniform sampling. Examples or applications are also described, in fields such as reaction monitoring and metabolomics, to illustrate the relevance and limitations of different methods.
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20
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Dey A, Charrier B, Lemaitre K, Ribay V, Eshchenko D, Schnell M, Melzi R, Stern Q, Cousin S, Kempf J, Jannin S, Dumez JN, Giraudeau P. Fine optimization of a dissolution dynamic nuclear polarization experimental setting for 13C NMR of metabolic samples. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2022; 3:183-202. [PMID: 37904870 PMCID: PMC10583282 DOI: 10.5194/mr-3-183-2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/16/2022] [Indexed: 11/01/2023]
Abstract
NMR-based analysis of metabolite mixtures provides crucial information on biological systems but mostly relies on 1D 1 H experiments for maximizing sensitivity. However, strong peak overlap of 1 H spectra often is a limitation for the analysis of inherently complex biological mixtures. Dissolution dynamic nuclear polarization (d-DNP) improves NMR sensitivity by several orders of magnitude, which enables 13 C NMR-based analysis of metabolites at natural abundance. We have recently demonstrated the successful introduction of d-DNP into a full untargeted metabolomics workflow applied to the study of plant metabolism. Here we describe the systematic optimization of d-DNP experimental settings for experiments at natural 13 C abundance and show how the resolution, sensitivity, and ultimately the number of detectable signals improve as a result. We have systematically optimized the parameters involved (in a semi-automated prototype d-DNP system, from sample preparation to signal detection, aiming at providing an optimization guide for potential users of such a system, who may not be experts in instrumental development). The optimization procedure makes it possible to detect previously inaccessible protonated 13 C signals of metabolites at natural abundance with at least 4 times improved line shape and a high repeatability compared to a previously reported d-DNP-enhanced untargeted metabolomic study. This extends the application scope of hyperpolarized 13 C NMR at natural abundance and paves the way to a more general use of DNP-hyperpolarized NMR in metabolomics studies.
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Affiliation(s)
- Arnab Dey
- Nantes Université, CNRS, CEISAM UMR 6230, 44000 Nantes, France
| | - Benoît Charrier
- Nantes Université, CNRS, CEISAM UMR 6230, 44000 Nantes, France
| | - Karine Lemaitre
- Nantes Université, CNRS, CEISAM UMR 6230, 44000 Nantes, France
| | - Victor Ribay
- Nantes Université, CNRS, CEISAM UMR 6230, 44000 Nantes, France
| | - Dmitry Eshchenko
- Bruker Biospin, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Marc Schnell
- Bruker Biospin, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Roberto Melzi
- Bruker Biospin, Viale V. Lancetti 43, 20158 Milan, Italy
| | - Quentin Stern
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1,
ENS de Lyon, Centre de RMN à Très Hauts Champs (CRMN), UMR5082,
69100 Villeurbanne, France
| | | | | | - Sami Jannin
- Université de Lyon, CNRS, Université Claude Bernard Lyon 1,
ENS de Lyon, Centre de RMN à Très Hauts Champs (CRMN), UMR5082,
69100 Villeurbanne, France
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21
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Fraser R, Rutjes FPJT, Feiters MC, Tessari M. Analysis of Complex Mixtures by Chemosensing NMR Using para-Hydrogen-Induced Hyperpolarization. Acc Chem Res 2022; 55:1832-1844. [PMID: 35709417 PMCID: PMC9260963 DOI: 10.1021/acs.accounts.1c00796] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Nuclear magnetic resonance (NMR) is a powerful technique for chemical
analysis. The use of NMR to investigate dilute analytes in complex
systems is, however, hampered by its relatively low sensitivity. An
additional obstacle is represented by the NMR signal overlap. Because
solutes in a complex mixture are usually not isotopically labeled,
NMR studies are often limited to 1H measurements, which,
because of the modest dispersion of the 1H resonances (typically
∼10 ppm), can result in challenging signal crowding. The low
NMR sensitivity issue can be alleviated by nuclear spin hyperpolarization
(i.e., transiently increasing the differences in nuclear spin populations),
which determines large NMR signal enhancements. This has been demonstrated
for hyperpolarization methods such as dynamic nuclear polarization,
spin-exchange optical pumping and para-hydrogen-induced
polarization (PHIP). In particular, PHIP has grown into a fast, efficient,
and versatile technique since the recent discovery of non-hydrogenative
routes to achieve nuclear spin hyperpolarization. For instance,
signal amplification by reversible exchange (SABRE)
can generate proton as well as heteronuclear spin hyperpolarization
in a few seconds in compounds that are able to transiently bind to
an iridium catalyst in the presence of para-hydrogen
in solution. The hyperpolarization transfer catalyst acts as a chemosensor
in the sense that it is selective for analytes that can coordinate
to the metal center, such as nitrogen-containing aromatic heterocycles,
sulfur heteroaromatic compounds, nitriles, Schiff bases, diaziridines,
carboxylic acids, and amines. We have demonstrated that the signal
enhancement achieved by SABRE allows rapid NMR detection and quantification
of a mixture of substrates down to low-micromolar concentration. Furthermore,
in the transient complex, the spin configuration of p-H2 can be easily converted to spin hyperpolarization
to produce up to 1000-fold enhanced NMR hydride signals. Because the
hydrides’ chemical shifts are highly sensitive to the structure
of the analyte associating with the iridium complex, they can be employed
as hyperpolarized “probes” to signal the presence of
specific compounds in the mixture. This indirect detection of the
analytes in solution provides important benefits in the case of complex
systems, as hydrides resonate in a region of the 1H spectrum
(at ca. −20 ppm) that is generally signal-free. The enhanced
sensitivity provided by non-hydrogenative PHIP (nhPHIP), together
with the absence of interference from the complex matrix (usually
resonating between 0 and 10 ppm), set the detection limit for this
NMR chemosensor down to sub-μM concentrations, approximately
3 orders of magnitude lower than for conventional NMR. This nhPHIP
approach represents, therefore, a powerful tool for NMR analysis of
dilute substrates in complex mixtures as it addresses at once the
issues of signal crowding and NMR sensitivity. Importantly, being
performed at high field inside the NMR spectrometer, the method allows
for rapid acquisition of multiple scans, multidimensional hyperpolarized
NMR spectra, in a fashion comparable to that of standard NMR measurements. In this Account, we focus on our chemosensing NMR technology, detailing
its principles, advantages, and limitations and presenting a number
of applications to real systems such as biofluids, beverages, and
natural extracts.
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Affiliation(s)
- Roan Fraser
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Martin C Feiters
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Marco Tessari
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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22
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Lhoste C, Lorandel B, Praud C, Marchand A, Mishra R, Dey A, Bernard A, Dumez JN, Giraudeau P. Ultrafast 2D NMR for the analysis of complex mixtures. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 130-131:1-46. [PMID: 36113916 DOI: 10.1016/j.pnmrs.2022.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 01/21/2022] [Accepted: 01/23/2022] [Indexed: 06/15/2023]
Abstract
2D NMR is extensively used in many different fields, and its potential for the study of complex biochemical or chemical mixtures has been widely demonstrated. 2D NMR gives the ability to resolve peaks that overlap in 1D spectra, while providing both structural and quantitative information. However, complex mixtures are often analysed in situations where the data acquisition time is a crucial limitation, due to an ongoing chemical reaction or a moving sample from a hyphenated technique, or to the high-throughput requirement associated with large sample collections. Among the great diversity of available fast 2D methods, ultrafast (or single-scan) 2D NMR is probably the most general and versatile approach for complex mixture analysis. Indeed, ultrafast NMR has undergone an impressive number of methodological developments that have helped turn it into an efficient analytical tool, and numerous applications to the analysis of mixtures have been reported. This review first summarizes the main concepts, features and practical limitations of ultrafast 2D NMR, as well as the methodological developments that improved its analytical potential. Then, a detailed description of the main applications of ultrafast 2D NMR to mixture analysis is given. The two major application fields of ultrafast 2D NMR are first covered, i.e., reaction/process monitoring and metabolomics. Then, the potential of ultrafast 2D NMR for the analysis of hyperpolarized mixtures is described, as well as recent developments in oriented media. This review focuses on high-resolution liquid-state 2D experiments (including benchtop NMR) that include at least one spectroscopic dimension (i.e., 2D spectroscopy and DOSY) but does not cover in depth applications without spectral resolution and/or in inhomogeneous fields.
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Affiliation(s)
- Célia Lhoste
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
| | | | - Clément Praud
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
| | - Achille Marchand
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
| | - Rituraj Mishra
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
| | - Arnab Dey
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
| | - Aurélie Bernard
- Nantes Université, CNRS, CEISAM UMR 6230, Nantes F-44000, France
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23
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Abstract
The widespread application of nuclear magnetic resonance (NMR) spectroscopy in detection is currently hampered by its inherently low sensitivity and complications resulting from the undesired signal overlap. Here, we report a detection scheme to address these challenges, where analytes are recognized by 19F-labeled probes to induce characteristic shifts of 19F resonances that can be used as "chromatographic" signatures to pin down each low-concentration analyte in complex mixtures. This unique signal transduction mechanism allows detection sensitivity to be enhanced by using massive chemically equivalent 19F atoms, which was achieved through the proper installation of nonafluoro-tert-butoxy groups on probes of high structural symmetry. It is revealed that the binding of an analyte to the probe can be sensed by as many as 72 chemically equivalent 19F atoms, allowing the quantification of analytes at nanomolar concentrations to be routinely performed by NMR. Applications on the detection of trace amounts of prohibited drug molecules and water contaminants were demonstrated. The high sensitivity and robust resolving ability of this approach represent a first step toward extending the application of NMR to scenarios that are now governed by chromatographic and mass spectrometry techniques. The detection scheme also makes possible the highly sensitive non-invasive multi-component analysis that is difficult to achieve by other analytical methods.
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Affiliation(s)
- Lixian Wen
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Huan Meng
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Siyi Gu
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Jian Wu
- Instrumental Analysis Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, P. R. China
| | - Yanchuan Zhao
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China.,Key Laboratory of Energy Regulation Materials, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
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24
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Tickner BJ, Zhivonitko VV. Advancing homogeneous catalysis for parahydrogen-derived hyperpolarisation and its NMR applications. Chem Sci 2022; 13:4670-4696. [PMID: 35655870 PMCID: PMC9067625 DOI: 10.1039/d2sc00737a] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 03/21/2022] [Indexed: 12/18/2022] Open
Abstract
Parahydrogen-induced polarisation (PHIP) is a nuclear spin hyperpolarisation technique employed to enhance NMR signals for a wide range of molecules. This is achieved by exploiting the chemical reactions of parahydrogen (para-H2), the spin-0 isomer of H2. These reactions break the molecular symmetry of para-H2 in a way that can produce dramatically enhanced NMR signals for reaction products, and are usually catalysed by a transition metal complex. In this review, we discuss recent advances in novel homogeneous catalysts that can produce hyperpolarised products upon reaction with para-H2. We also discuss hyperpolarisation attained in reversible reactions (termed signal amplification by reversible exchange, SABRE) and focus on catalyst developments in recent years that have allowed hyperpolarisation of a wider range of target molecules. In particular, recent examples of novel ruthenium catalysts for trans and geminal hydrogenation, metal-free catalysts, iridium sulfoxide-containing SABRE systems, and cobalt complexes for PHIP and SABRE are reviewed. Advances in this catalysis have expanded the types of molecules amenable to hyperpolarisation using PHIP and SABRE, and their applications in NMR reaction monitoring, mechanistic elucidation, biomedical imaging, and many other areas, are increasing.
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Affiliation(s)
- Ben J Tickner
- NMR Research Unit, Faculty of Science, University of Oulu P.O. Box 3000 Oulu 90014 Finland
- Department of Chemical and Biological Physics, Faculty of Chemistry, Weizmann Institute of Science Rehovot 7610001 Israel
| | - Vladimir V Zhivonitko
- NMR Research Unit, Faculty of Science, University of Oulu P.O. Box 3000 Oulu 90014 Finland
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25
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Eriksson SL, Lindale JR, Li X, Warren WS. Improving SABRE hyperpolarization with highly nonintuitive pulse sequences: Moving beyond avoided crossings to describe dynamics. SCIENCE ADVANCES 2022; 8:eabl3708. [PMID: 35294248 PMCID: PMC8926330 DOI: 10.1126/sciadv.abl3708] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/24/2022] [Indexed: 05/26/2023]
Abstract
Signal amplification by reversible exchange (SABRE) creates "hyperpolarization" (large spin magnetization) using a transition metal catalyst and parahydrogen, addressing the sensitivity limitations of magnetic resonance. SABRE and its heteronuclear variant X-SABRE are simple, fast, and general, but to date have not produced polarization levels as large as more established methods. We show here that the commonly used theoretical framework for these applications, which focuses on avoided crossings (also called level anticrossings or LACs), steer current SABRE and X-SABRE experiments away from optimal solutions. Accurate simulations show astonishingly rich and unexpected dynamics in SABRE/X-SABRE, which we explain with a combination of perturbation theory and average Hamiltonian approaches. This theoretical picture predicts simple pulse sequences with field values far from LACs (both instantaneously and on average) using different terms in the effective Hamiltonian to strategically control evolution and improve polarization transfer. Substantial signal enhancements under such highly nonintuitive conditions are verified experimentally.
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Affiliation(s)
- Shannon L. Eriksson
- Department of Chemistry, Duke University, Durham, NC 27708, USA
- School of Medicine, Duke University, Durham, NC 27708, USA
| | | | - Xiaoqing Li
- Department of Physics, Duke University, Durham, NC 27708, USA
| | - Warren S. Warren
- Department of Chemistry, Duke University, Durham, NC 27708, USA
- School of Medicine, Duke University, Durham, NC 27708, USA
- Department of Physics, Duke University, Durham, NC 27708, USA
- Department of Physics, Chemistry, Biomedical Engineering, and Radiology, Duke University, Durham, NC 27704, USA
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26
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Tickner BJ, Komulainen S, Palosaari S, Heikkinen J, Lehenkari P, Zhivonitko VV, Telkki VV. Hyperpolarised NMR to aid molecular profiling of electronic cigarette aerosols. RSC Adv 2022; 12:1479-1485. [PMID: 35425197 PMCID: PMC8979170 DOI: 10.1039/d1ra07376a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/15/2021] [Indexed: 11/21/2022] Open
Abstract
Signal amplification by reversible exchange (SABRE) hyperpolarisation is used to enhance the NMR signals of nicotine and acrolein in methanol-d4 solutions of electronic cigarette aerosols. Consequently, detection of 74 μM nicotine is possible in just a single scan 1H NMR spectrum. The first example of an aldehyde hyperpolarised using SABRE is demonstrated and we work towards novel real-world applications of SABRE-hyperpolarised NMR for chemical analysis.
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Affiliation(s)
- Ben J Tickner
- NMR Research Unit, Faculty of Science, University of Oulu 90014 Finland
| | - Sanna Komulainen
- NMR Research Unit, Faculty of Science, University of Oulu 90014 Finland
| | - Sanna Palosaari
- Cancer and Translational Medicine Research Unit, Faculty of Medicine, University of Oulu 90014 Finland
- Medical Research Center Oulu, Faculty of Medicine, University of Oulu and Oulu University Hospital 90014 Finland
| | - Janne Heikkinen
- Cancer and Translational Medicine Research Unit, Faculty of Medicine, University of Oulu 90014 Finland
| | - Petri Lehenkari
- Cancer and Translational Medicine Research Unit, Faculty of Medicine, University of Oulu 90014 Finland
- Medical Research Center Oulu, Faculty of Medicine, University of Oulu and Oulu University Hospital 90014 Finland
- Division of Orthopedic Surgery, Oulu University Hospital 90220 Finland
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27
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Norcott PL. Selective NMR detection of individual reaction components hyperpolarised by reversible exchange with para-hydrogen. Phys Chem Chem Phys 2022; 24:13527-13533. [DOI: 10.1039/d2cp01657e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NMR spectroscopy can sometimes be hampered by two inherent weaknesses: low sensitivity and overlap of signals in complex mixtures. Hyperpolarisation techniques using para-hydrogen (including the method known as SABRE) can...
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28
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Sellies L, Aspers RLEG, Feiters MC, Rutjes FPJT, Tessari M. Parahydrogen Hyperpolarization Allows Direct NMR Detection of α-Amino Acids in Complex (Bio)mixtures. Angew Chem Int Ed Engl 2021; 60:26954-26959. [PMID: 34534406 PMCID: PMC9299667 DOI: 10.1002/anie.202109588] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Indexed: 12/12/2022]
Abstract
The scope of non-hydrogenative parahydrogen hyperpolarization (nhPHIP) techniques has been expanding over the last years, with the continuous addition of important classes of substrates. For example, pyruvate can now be hyperpolarized using the Signal Amplification By Reversible Exchange (SABRE) technique, offering a fast, efficient and low-cost PHIP alternative to Dynamic Nuclear Polarization for metabolic imaging studies. Still, important biomolecules such as amino acids have so far resisted PHIP, unless properly functionalized. Here, we report on an approach to nhPHIP for unmodified α-amino acids that allows their detection and quantification in complex mixtures at sub-micromolar concentrations. This method was tested on human urine, in which natural α-amino acids could be measured after dilution with methanol without any additional sample treatment.
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Affiliation(s)
- Lisanne Sellies
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525AJNijmegenThe Netherlands
| | - Ruud L. E. G. Aspers
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525AJNijmegenThe Netherlands
| | - Martin C. Feiters
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525AJNijmegenThe Netherlands
| | - Floris P. J. T. Rutjes
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525AJNijmegenThe Netherlands
| | - Marco Tessari
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525AJNijmegenThe Netherlands
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29
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Sellies L, Aspers RLEG, Feiters MC, Rutjes FPJT, Tessari M. Parahydrogen Hyperpolarization Allows Direct NMR Detection of α‐Amino Acids in Complex (Bio)mixtures. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109588] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Lisanne Sellies
- Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525AJ Nijmegen The Netherlands
| | - Ruud L. E. G. Aspers
- Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525AJ Nijmegen The Netherlands
| | - Martin C. Feiters
- Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525AJ Nijmegen The Netherlands
| | - Floris P. J. T. Rutjes
- Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525AJ Nijmegen The Netherlands
| | - Marco Tessari
- Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525AJ Nijmegen The Netherlands
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30
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Ausmees K, Reimets N, Reile I. Parahydrogen hyperpolarization of minimally altered urine samples for sensitivity enhanced NMR metabolomics. Chem Commun (Camb) 2021; 58:463-466. [PMID: 34908034 DOI: 10.1039/d1cc05665d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Parahydrogen hyperpolarization has been shown to enhance NMR sensitivity in urine analysis by several orders of magnitude if urine samples are prepared by solid phase extraction (SPE). We present a different approach, developed for minimal sample alteration before analysis. Removing SPE from the workflow allows to retain a wider range of metabolites and paves the way towards more universal hyperpolarized NMR metabolomics of low abundance metabolites.
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Affiliation(s)
- Kerti Ausmees
- The National Institute of Chemical Physics and Biophysics (NICPB), Tallinn, Estonia.
| | - Nele Reimets
- The National Institute of Chemical Physics and Biophysics (NICPB), Tallinn, Estonia.
| | - Indrek Reile
- The National Institute of Chemical Physics and Biophysics (NICPB), Tallinn, Estonia.
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31
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Pravdivtsev AN, Kempf N, Plaumann M, Bernarding J, Scheffler K, Hövener J, Buckenmaier K. Coherent Evolution of Signal Amplification by Reversible Exchange in Two Alternating Fields (alt-SABRE). Chemphyschem 2021; 22:2381-2386. [PMID: 34546634 PMCID: PMC9292956 DOI: 10.1002/cphc.202100543] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/16/2021] [Indexed: 11/06/2022]
Abstract
Parahydrogen (pH2 ) is a convenient and cost-efficient source of spin order to enhance the magnetic resonance signal. Previous work showed that transient interaction of pH2 with a metal organic complex in a signal amplification by reversible exchange (SABRE) experiment enabled more than 10 % polarization for some 15 N molecules. Here, we analyzed a variant of SABRE, consisting of a magnetic field alternating between a low field of ∼1 μT, where polarization transfer is expected to take place, and a higher field >50 μT (alt-SABRE). These magnetic fields affected the amplitude and frequency of polarization transfer. Deviation of a lower magnetic field from a "perfect" condition of level anti-crossing increases the frequency of polarization transfer that can be exploited for polarization of short-lived transient SABRE complexes. Moreover, the coherences responsible for polarization transfer at a lower field persisted during magnetic field variation and continued their spin evolution at higher field with a frequency of 2.5 kHz at 54 μT. The latter should be taken into consideration for an efficient alt-SABRE. Theoretical and experimental findings were exemplified with Iridium N-heterocyclic carbene SABRE complex and 15 N-acetonitrole, where a 30 % higher 15 N polarization with alt-SABRE compared to common SABRE was reached.
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Affiliation(s)
- Andrey N. Pravdivtsev
- Molecular Imaging North Competence Center (MOIN CC)Section Biomedical ImagingDepartment of Radiology and NeuroradiologyUniversity Medical Center KielKiel UniversityAm Botanischen Garten 1424114KielGermany
| | - Nicolas Kempf
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
| | - Markus Plaumann
- Institute for Biometrics and Medical InformaticsOtto-von-Guericke UniversityBuilding 02, Leipziger Str. 4439120MagdeburgGermany
| | - Johannes Bernarding
- Institute for Biometrics and Medical InformaticsOtto-von-Guericke UniversityBuilding 02, Leipziger Str. 4439120MagdeburgGermany
| | - Klaus Scheffler
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
| | - Jan‐Bernd Hövener
- Molecular Imaging North Competence Center (MOIN CC)Section Biomedical ImagingDepartment of Radiology and NeuroradiologyUniversity Medical Center KielKiel UniversityAm Botanischen Garten 1424114KielGermany
| | - Kai Buckenmaier
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
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32
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Pravdivtsev AN, Buntkowsky G, Duckett SB, Koptyug IV, Hövener J. Parahydrogen-Induced Polarization of Amino Acids. Angew Chem Int Ed Engl 2021; 60:23496-23507. [PMID: 33635601 PMCID: PMC8596608 DOI: 10.1002/anie.202100109] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/24/2021] [Indexed: 12/13/2022]
Abstract
Nuclear magnetic resonance (NMR) has become a universal method for biochemical and biomedical studies, including metabolomics, proteomics, and magnetic resonance imaging (MRI). By increasing the signal of selected molecules, the hyperpolarization of nuclear spin has expanded the reach of NMR and MRI even further (e.g. hyperpolarized solid-state NMR and metabolic imaging in vivo). Parahydrogen (pH2 ) offers a fast and cost-efficient way to achieve hyperpolarization, and the last decade has seen extensive advances, including the synthesis of new tracers, catalysts, and transfer methods. The portfolio of hyperpolarized molecules now includes amino acids, which are of great interest for many applications. Here, we provide an overview of the current literature and developments in the hyperpolarization of amino acids and peptides.
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Affiliation(s)
- Andrey N. Pravdivtsev
- Section Biomedical ImagingMolecular Imaging North Competence Center (MOIN CC)Department of Radiology and NeuroradiologyUniversity Medical Center Schleswig-Holstein (UKSH)Kiel UniversityAm Botanischen Garten 1424118KielGermany
| | - Gerd Buntkowsky
- Technical University DarmstadtEduard-Zintl-Institute for Inorganic and Physical ChemistryAlarich-Weiss-Strasse 864287DarmstadtGermany
| | - Simon B. Duckett
- Department Center for Hyperpolarization in Magnetic Resonance (CHyM)Department of ChemistryUniversity of York, HeslingtonYorkYO10 5NYUK
| | - Igor V. Koptyug
- International Tomography CenterSB RAS3A Institutskaya st.630090NovosibirskRussia
- Novosibirsk State University2 Pirogova st.630090NovosibirskRussia
| | - Jan‐Bernd Hövener
- Section Biomedical ImagingMolecular Imaging North Competence Center (MOIN CC)Department of Radiology and NeuroradiologyUniversity Medical Center Schleswig-Holstein (UKSH)Kiel UniversityAm Botanischen Garten 1424118KielGermany
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33
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Pravdivtsev AN, Buntkowsky G, Duckett SB, Koptyug IV, Hövener J. Parawasserstoff‐induzierte Polarisation von Aminosäuren. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202100109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Andrey N. Pravdivtsev
- Section Biomedical Imaging Molecular Imaging North Competence Center (MOIN CC) Department of Radiology and Neuroradiology University Medical Center Schleswig-Holstein (UKSH) Kiel University Am Botanischen Garten 14 24118 Kiel Deutschland
| | - Gerd Buntkowsky
- Technical University Darmstadt Eduard-Zintl-Institute for Inorganic and Physical Chemistry Alarich-Weiss-Straße 8 64287 Darmstadt Deutschland
| | - Simon B. Duckett
- Department Center for Hyperpolarization in Magnetic Resonance (CHyM) Department of Chemistry University of York, Heslington York YO10 5NY Vereinigtes Königreich
| | - Igor V. Koptyug
- International Tomography Center SB RAS 3A Institutskaya st. 630090 Novosibirsk Russland
- Novosibirsk State University 2 Pirogova st. 630090 Novosibirsk Russland
| | - Jan‐Bernd Hövener
- Section Biomedical Imaging Molecular Imaging North Competence Center (MOIN CC) Department of Radiology and Neuroradiology University Medical Center Schleswig-Holstein (UKSH) Kiel University Am Botanischen Garten 14 24118 Kiel Deutschland
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34
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Mandal R, Pham P, Hilty C. Characterization of protein-ligand interactions by SABRE. Chem Sci 2021; 12:12950-12958. [PMID: 34745525 PMCID: PMC8515190 DOI: 10.1039/d1sc03404a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022] Open
Abstract
Nuclear spin hyperpolarization through signal amplification by reversible exchange (SABRE), the non-hydrogenative version of para-hydrogen induced polarization, is demonstrated to enhance sensitivity for the detection of biomacromolecular interactions. A target ligand for the enzyme trypsin includes the binding motif for the protein, and at a distant location a heterocyclic nitrogen atom for interacting with a SABRE polarization transfer catalyst. This molecule, 4-amidinopyridine, is hyperpolarized with 50% para-hydrogen to yield enhancement values ranging from −87 and −34 in the ortho and meta positions of the heterocyclic nitrogen, to −230 and −110, for different solution conditions. Ligand binding is identified by flow-NMR, in a two-step process that separately optimizes the polarization transfer in methanol while detecting the interaction in a predominantly aqueous medium. A single scan Carr–Purcell–Meiboom–Gill (CPMG) experiment identifies binding by the change in R2 relaxation rate. The SABRE hyperpolarization technique provides a cost effective means to enhance NMR of biological systems, for the identification of protein–ligand interactions and other applications. Protein–ligand binding interactions are characterized by the para-H2 based hyperpolarization technique SABRE and flow-NMR. Binding to the protein is identified by R2 change of a ligand first interacting with the Ir polarization transfer catalyst.![]()
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Affiliation(s)
- Ratnamala Mandal
- Department of Chemistry, Texas A&M University 3255 TAMU College Station TX 77843 USA
| | - Pierce Pham
- Department of Chemistry, Texas A&M University 3255 TAMU College Station TX 77843 USA
| | - Christian Hilty
- Department of Chemistry, Texas A&M University 3255 TAMU College Station TX 77843 USA
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35
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Reimets N, Ausmees K, Vija S, Reile I. Developing Analytical Applications for Parahydrogen Hyperpolarization: Urinary Elimination Pharmacokinetics of Nicotine. Anal Chem 2021; 93:9480-9485. [PMID: 34180227 DOI: 10.1021/acs.analchem.1c01281] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Nuclear magnetic resonance spectroscopy (NMR) is a valuable analytical tool with applications in a vast array of research fields from chemistry and biology to medicine and beyond. NMR is renowned for its straightforward data interpretation and quantitative properties, making it attractive for pharmacokinetic applications, where drug metabolism pathways, concentrations, and kinetics need to be evaluated. However, pharmacologically active compounds and their metabolites in biofluids often appear in minute concentrations, well below the detection limit of NMR. Herein, we demonstrate how parahydrogen hyperpolarization overcomes this sensitivity barrier, allowing us to detect mid-nanomolar concentrations of a drug and a drug metabolite in a biofluid matrix. The performance of the method is demonstrated by monitoring nicotine and cotinine urinary elimination, reflected by their concentrations in urine during the onset and withdrawal from nicotine consumption. An NMR limit of detection of 0.1 μM and a limit of quantitation of 0.7 μM is achieved in a practical pharmacokinetics scenario where precise quantitative and qualitative analysis is desired.
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Affiliation(s)
- Nele Reimets
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Kerti Ausmees
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Sirje Vija
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Indrek Reile
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
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36
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Sellies L, Aspers R, Tessari M. Determination of hydrogen exchange and relaxation parameters in PHIP complexes at micromolar concentrations. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021; 2:331-340. [PMID: 37904761 PMCID: PMC10539837 DOI: 10.5194/mr-2-331-2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 04/30/2021] [Indexed: 11/01/2023]
Abstract
Non-hydrogenative para-hydrogen-induced polarization (PHIP) is a fast, efficient and relatively inexpensive approach to enhance nuclear magnetic resonance (NMR) signals of small molecules in solution. The efficiency of this technique depends on the interplay of NMR relaxation and kinetic processes, which, at high concentrations, can be characterized by selective inversion experiments. However, in the case of dilute solutions this approach is clearly not viable. Here, we present alternative PHIP-based NMR experiments to determine hydrogen and hydride relaxation parameters as well as the rate constants for para-hydrogen association with and dissociation from asymmetric PHIP complexes at micromolar concentrations. Access to these parameters is necessary to understand and improve the PHIP enhancements of (dilute) substrates present in, for instance, biofluids and natural extracts.
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Affiliation(s)
- Lisanne Sellies
- Institute for Molecules and Materials, Radboud University, Nijmegen,
6525AJ, the Netherlands
| | - Ruud L. E. G. Aspers
- Institute for Molecules and Materials, Radboud University, Nijmegen,
6525AJ, the Netherlands
| | - Marco Tessari
- Institute for Molecules and Materials, Radboud University, Nijmegen,
6525AJ, the Netherlands
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37
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Rayner PJ, Gillions JP, Hannibal VD, John RO, Duckett SB. Hyperpolarisation of weakly binding N-heterocycles using signal amplification by reversible exchange. Chem Sci 2021; 12:5910-5917. [PMID: 34168816 PMCID: PMC8179664 DOI: 10.1039/d0sc06907h] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/22/2021] [Indexed: 12/23/2022] Open
Abstract
Signal Amplification by Reversible Exchange (SABRE) is a catalytic method for improving the detection of molecules by magnetic resonance spectroscopy. It achieves this by simultaneously binding the target substrate (sub) and para-hydrogen to a metal centre. To date, sterically large substrates are relatively inaccessible to SABRE due to their weak binding leading to catalyst destabilisation. We overcome this problem here through a simple co-ligand strategy that allows the hyperpolarisation of a range of weakly binding and sterically encumbered N-heterocycles. The resulting 1H NMR signal size is increased by up to 1400 times relative to their more usual Boltzmann controlled levels at 400 MHz. Hence, a significant reduction in scan time is achieved. The SABRE catalyst in these systems takes the form [IrX(H)2(NHC)(sulfoxide)(sub)] where X = Cl, Br or I. These complexes are shown to undergo very rapid ligand exchange and lower temperatures dramatically improve the efficiency of these SABRE catalysts.
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Affiliation(s)
- Peter J Rayner
- Centre for Hyperpolarisation in Magnetic Resonance (CHyM), Department of Chemistry, University of York Heslington York YO10 5DD UK
| | - Joseph P Gillions
- Centre for Hyperpolarisation in Magnetic Resonance (CHyM), Department of Chemistry, University of York Heslington York YO10 5DD UK
| | - Valentin D Hannibal
- Centre for Hyperpolarisation in Magnetic Resonance (CHyM), Department of Chemistry, University of York Heslington York YO10 5DD UK
| | - Richard O John
- Centre for Hyperpolarisation in Magnetic Resonance (CHyM), Department of Chemistry, University of York Heslington York YO10 5DD UK
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance (CHyM), Department of Chemistry, University of York Heslington York YO10 5DD UK
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38
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Muhammad SR, Greer RB, Ramirez SB, Goodson BM, Fout AR. Cobalt-Catalyzed Hyperpolarization of Structurally Intact Olefins. ACS Catal 2021. [DOI: 10.1021/acscatal.0c03727] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Safiyah R. Muhammad
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Rianna B. Greer
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Steven B. Ramirez
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Boyd M. Goodson
- Department of Chemistry and Biochemistry and Materials Technology Center, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Alison R. Fout
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
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39
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Mandal R, Pham P, Hilty C. Nuclear Spin Hyperpolarization of NH 2 - and CH 3 -Substituted Pyridine and Pyrimidine Moieties by SABRE. Chemphyschem 2020; 21:2166-2172. [PMID: 32783276 DOI: 10.1002/cphc.202000483] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/23/2020] [Indexed: 01/06/2023]
Abstract
Hyperpolarization of N-heterocycles with signal amplification by reversible exchange (SABRE) induces NMR sensitivity gains for biological molecules. Substitutions with functional groups, in particular in the ortho-position of the heterocycle, however, result in low polarization using a typical Ir catalyst with a bis-mesityl N-heterocyclic carbene ligand for SABRE, presumably due to steric hindrance. With the addition of allylamine or acetonitrile as coligands to the precatalyst chloro(1,5-cyclooctadiene)[4,5-dimethyl-1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene] iridium, the 1 H signal enhancement increased in several substrates with ortho NH2 substitutions. For example, for a proton in 2,4-diaminopyrimidine, the enhancement factors increased from -7±1 to -210±20 with allylamine or to -160±10 with acetonitrile. CH3 substituted molecules yielded maximum signal enhancements of -25±7 with acetonitrile addition, which is considerably less than the corresponding NH2 substituted molecules, despite exhibiting similar steric size. With the more electron-donating NH2 substitution resulting in greater enhancement, it is concluded that steric hindrance is not the only dominant factor in determining the polarizability of the CH3 substituted compounds. The addition of allylamine increased the signal enhancement for the 290 Da trimethoprim, a molecule with a 2,4-diaminopyrimidine moiety serving as an antibacterial agent, to -70.
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Affiliation(s)
- Ratnamala Mandal
- Department of Chemistry, Texas A&M University, College Station, TX, 77843-3255, USA
| | - Pierce Pham
- Department of Chemistry, Texas A&M University, College Station, TX, 77843-3255, USA
| | - Christian Hilty
- Department of Chemistry, Texas A&M University, College Station, TX, 77843-3255, USA
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40
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Colell JFP, Logan AWJ, Zhou Z, Lindale JR, Laasner R, Shchepin RV, Chekmenev EY, Blum V, Warren WS, Malcolmson SJ, Theis T. Rational ligand choice extends the SABRE substrate scope. Chem Commun (Camb) 2020; 56:9336-9339. [PMID: 32671356 PMCID: PMC7443256 DOI: 10.1039/d0cc01330g] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Here we report on chelating ligands for Signal Amplification By Reversible Exchange (SABRE) catalysts that permit hyperpolarisation on otherwise sterically hindered substrates. We demonstrate 1H enhancements of ∼100-fold over 8.5 T thermal for 2-substituted pyridines, and smaller, yet significant enhancements for provitamin B6 and caffeine. We also show 15N-enhancements of ∼1000-fold and 19F-enhancements of 30-fold.
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Affiliation(s)
| | | | - Zijian Zhou
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | | | - Raul Laasner
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Roman V. Shchepin
- Department of Chemistry, Biology, and Health Sciences, South Dakota School of Mines and Technology, Rapid City, South Dakota 57701, USA
| | - Eduard Y. Chekmenev
- Russian Academy of Sciences, Leninskiy Prospekt 14, 119991 Moscow, Russia
- Department of Chemistry, Integrative Biosciences (IBio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Volker Blum
- Department of Chemistry, Duke University, Durham, NC 27708, USA
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Warren S. Warren
- Department of Chemistry, Duke University, Durham, NC 27708, USA
- Departments of Physics, Radiology and Biomedical Engineering, Duke University, Durham, NC 27707, USA
| | | | - Thomas Theis
- Department of Chemistry, Duke University, Durham, NC 27708, USA
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695
- Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC, USA
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41
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Chae H, Min S, Jeong HJ, Namgoong SK, Oh S, Kim K, Jeong K. Organic Reaction Monitoring of a Glycine Derivative Using Signal Amplification by Reversible Exchange-Hyperpolarized Benchtop Nuclear Magnetic Resonance Spectroscopy. Anal Chem 2020; 92:10902-10907. [DOI: 10.1021/acs.analchem.0c01270] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Heelim Chae
- Department of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Sein Min
- Department of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Hye Jin Jeong
- Department of Chemistry, Korea Military Academy, Seoul 01805, South Korea
| | - Sung Keon Namgoong
- Department of Chemistry, Seoul Women’s University, Seoul 01797, South Korea
| | - Sangwon Oh
- Korea Research Institute of Standards and Science, Daejeon 34113, South Korea
| | - Kiwoong Kim
- Korea Research Institute of Standards and Science, Daejeon 34113, South Korea
- Deparment of Medical Physics, University of Science and Technology, Daejeon 34113, South Korea
| | - Keunhong Jeong
- Department of Chemistry, Korea Military Academy, Seoul 01805, South Korea
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42
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Fekete M, Ahwal F, Duckett SB. Remarkable Levels of 15N Polarization Delivered through SABRE into Unlabeled Pyridine, Pyrazine, or Metronidazole Enable Single Scan NMR Quantification at the mM Level. J Phys Chem B 2020; 124:4573-4580. [PMID: 32383603 PMCID: PMC7277555 DOI: 10.1021/acs.jpcb.0c02583] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
While many drugs and metabolites contain nitrogen, harnessing their diagnostic 15N NMR signature for their characterization is underutilized because of inherent detection difficulties. Here, we demonstrate how precise ultralow field signal amplification by reversible exchange (±0.2 mG) in conjunction parahydrogen and an iridium precatalyst of the form IrCl(COD)(NHC) with the coligand d9-benzylamine allows the naturally abundant 15N NMR signatures of pyridine, pyrazine, metronidazole, and acetonitrile to be readily detected at 9.4 T in single NMR observations through >50% 15N polarization levels. These signals allow for rapid and precise reagent quantification via a response that varies linearly over the 2-70 mM concentration range.
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Affiliation(s)
- Marianna Fekete
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Fadi Ahwal
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
| | - Simon B Duckett
- Department of Chemistry, University of York, Heslington, York YO10 5DD, U.K
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43
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Buckenmaier K, Scheffler K, Plaumann M, Fehling P, Bernarding J, Rudolph M, Back C, Koelle D, Kleiner R, Hövener J, Pravdivtsev AN. Multiple Quantum Coherences Hyperpolarized at Ultra-Low Fields. Chemphyschem 2019; 20:2823-2829. [PMID: 31536665 PMCID: PMC6900040 DOI: 10.1002/cphc.201900757] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 09/17/2019] [Indexed: 11/26/2022]
Abstract
The development of hyperpolarization technologies enabled several yet exotic NMR applications at low and ultra-low fields (ULF), where without hyperpolarization even the detection of a signal from analytes is a challenge. Herein, we present a method for the simultaneous excitation and observation of homo- and heteronuclear multiple quantum coherences (from zero up to the third-order), which give an additional degree of freedom for ULF NMR experiments, where the chemical shift variation is negligible. The approach is based on heteronuclear correlated spectroscopy (COSY); its combination with a phase-cycling scheme allows the selective observation of multiple quantum coherences of different orders. The nonequilibrium spin state and multiple spin orders are generated by signal amplification by reversible exchange (SABRE) and detected at ULF with a superconducting quantum interference device (SQUID)-based NMR system.
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Affiliation(s)
- Kai Buckenmaier
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
| | - Klaus Scheffler
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
- Department for Biomedical Magnetic ResonanceUniversity of TübingenHoppe-Seyler-Str. 372076TübingenGermany
| | - Markus Plaumann
- Institute for Biometrics and Medical InformaticsOtto-von-Guericke University Building 02Leipziger Str. 4439120MagdeburgGermany
| | - Paul Fehling
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
| | - Johannes Bernarding
- Institute for Biometrics and Medical InformaticsOtto-von-Guericke University Building 02Leipziger Str. 4439120MagdeburgGermany
| | - Matthias Rudolph
- High-Field Magnetic Resonance CenterMax Planck Institute for Biological CyberneticsMax-Planck-Ring 1172076TübingenGermany
- Physikalisches Institut and Center for Quantum Science (CQ) in LISAUniversity of TübingenAuf der Morgenstelle 1472076TübingenGermany
| | - Christoph Back
- Physikalisches Institut and Center for Quantum Science (CQ) in LISAUniversity of TübingenAuf der Morgenstelle 1472076TübingenGermany
| | - Dieter Koelle
- Physikalisches Institut and Center for Quantum Science (CQ) in LISAUniversity of TübingenAuf der Morgenstelle 1472076TübingenGermany
| | - Reinhold Kleiner
- Physikalisches Institut and Center for Quantum Science (CQ) in LISAUniversity of TübingenAuf der Morgenstelle 1472076TübingenGermany
| | - Jan‐Bernd Hövener
- Section Biomedical Imaging Molecular Imaging North Competence Center (MOIN CC) Department of Radiology and Neuroradiology University Medical Center KielKiel UniversityAm Botanischen Garten 1424114KielGermany
| | - Andrey N. Pravdivtsev
- Section Biomedical Imaging Molecular Imaging North Competence Center (MOIN CC) Department of Radiology and Neuroradiology University Medical Center KielKiel UniversityAm Botanischen Garten 1424114KielGermany
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44
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Barskiy DA, Knecht S, Yurkovskaya AV, Ivanov KL. SABRE: Chemical kinetics and spin dynamics of the formation of hyperpolarization. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:33-70. [PMID: 31779885 DOI: 10.1016/j.pnmrs.2019.05.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 05/16/2019] [Indexed: 05/22/2023]
Abstract
In this review, we present the physical principles of the SABRE (Signal Amplification By Reversible Exchange) method. SABRE is a promising hyperpolarization technique that enhances NMR signals by transferring spin order from parahydrogen (an isomer of the H2 molecule that is in a singlet nuclear spin state) to a substrate that is to be polarized. Spin order transfer takes place in a transient organometallic complex which binds both parahydrogen and substrate molecules; after dissociation of the SABRE complex, free hyperpolarized substrate molecules are accumulated in solution. An advantage of this method is that the substrate is not modified chemically, and its polarization can be regenerated multiple times by bubbling fresh parahydrogen through the solution. Thus, SABRE requires two key ingredients: (i) polarization transfer and (ii) chemical exchange of both parahydrogen and substrate. While there are several excellent reviews on applications of SABRE, the background of the method is discussed less frequently. In this review we aim to explain in detail how SABRE hyperpolarization is formed, focusing on key aspects of both spin dynamics and chemical kinetics, as well as on the interplay between them. Hence, we first cover the known spin order transfer methods applicable to SABRE - cross-relaxation, coherent spin mixing at avoided level crossings, and coherence transfer - and discuss their practical implementation for obtaining SABRE polarization in the most efficient way. Second, we introduce and explain the principle of SABRE hyperpolarization techniques that operate at ultralow (<1 μT), at low (1μT to 0.1 T) and at high (>0.1 T) magnetic fields. Finally, chemical aspects of SABRE are discussed in detail, including chemical systems that are amenable to SABRE and the exchange processes that are required for polarization formation. A theoretical treatment of the spin dynamics and their interplay with chemical kinetics is also presented. This review outlines known aspects of SABRE and provides guidelines for the design of new SABRE experiments, with the goal of solving practical problems of enhancing weak NMR signals.
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Affiliation(s)
- Danila A Barskiy
- Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Stephan Knecht
- Eduard-Zintl Institute for Inorganic and Physical Chemistry, TU Darmstadt, Darmstadt 64287, Germany; Department of Radiology, Medical Physics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Alexandra V Yurkovskaya
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Konstantin L Ivanov
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia.
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45
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Štěpánek P, Kantola AM. Low-Concentration Measurements of Nuclear Spin-Induced Optical Rotation Using SABRE Hyperpolarization. J Phys Chem Lett 2019; 10:5458-5462. [PMID: 31454246 PMCID: PMC7076727 DOI: 10.1021/acs.jpclett.9b02194] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
Nuclear spin-induced optical rotation (NSOR) is a promising phenomenon for molecular structure elucidation due to its sensitivity to electronic structure near atomic nuclei. It is the only experimentally verified nuclear magneto-optic effect (NMOE), so far observed usually in neat liquids or in concentrated binary mixtures, with the proportion of the minor component at least 10%. We report a method to extend the lower-concentration range of NSOR measurements by 2 orders of magnitude by employing continuous-flow SABRE (signal amplification by reversible exchange) hyperpolarization. This approach significantly increases the sensitivity of NSOR and enables its detection in dilute samples, as demonstrated with measurements of NSOR of 90 mmol/L solutions of pyridine and pyrazine. The results are compared with first-principles calculations, and good agreement is found. The possibility to measure low-concentration solutions significantly extends the pool of samples available for further studies of NMOEs.
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46
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Rayner PJ, Tickner BJ, Iali W, Fekete M, Robinson AD, Duckett SB. Relayed hyperpolarization from para-hydrogen improves the NMR detectability of alcohols. Chem Sci 2019; 10:7709-7717. [PMID: 31588319 PMCID: PMC6764278 DOI: 10.1039/c9sc02765c] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 06/28/2019] [Indexed: 01/02/2023] Open
Abstract
The detection of alcohols by magnetic resonance techniques is important for their characterization and the monitoring of chemical change. Hyperpolarization processes can make previously inpractical measurements, such as the determination of low concentration intermediates, possible. Here, we investigate the SABRE-Relay method in order to define its key characteristics and improve the resulting 1H NMR signal gains which subsequently approach 103 per proton. We identify optimal amine proton transfer agents for SABRE-Relay and show how catalyst structure influences the outcome. The breadth of the method is revealed by expansion to more complex alcohols and the polarization of heteronuclei.
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Affiliation(s)
- Peter J Rayner
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
| | - Ben J Tickner
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
| | - Wissam Iali
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
| | - Marianna Fekete
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
| | - Alastair D Robinson
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , Heslington , YO10 5DD , UK .
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47
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Stanbury EV, Richardson PM, Duckett SB. Understanding substrate substituent effects to improve catalytic efficiency in the SABRE hyperpolarisation process. Catal Sci Technol 2019; 9:3914-3922. [PMID: 31814960 PMCID: PMC6836623 DOI: 10.1039/c9cy00396g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 06/04/2019] [Indexed: 01/19/2023]
Abstract
The use of parahydrogen based hyperpolarisation in NMR is becoming more widespread due to the rapidly expanding range of suitable target molecules and low-cost of parahydrogen production. Hyperpolarisation via SABRE catalysis employs a metal complex to transfer polarisation from parahydrogen into a substrate whilst they are bound. In this paper we present a quantitative study of substrate-iridium ligation effects by reference to the substrates 4-chloropyridine (A), 4-pyridinecarboxaldehyde methyl hemiacetal (B), 4-methylpyridine (C) and 4-methoxypyridine (D), and evaluate the role they play in the SABRE catalysis. Substrates whose substituents enable stronger associations yield slower substrate dissociation rates (k d). A series of variable temperature studies link these exchange rates to optimal SABRE performance and reveal the critical impact of NMR relaxation times (T 1). Longer catalyst residence times are shown to result in shorter substrate T 1 values in solution as binding to iridium promotes relaxation thereby not only reducing SABRE efficiency but decreasing the overall level of achieved hyperpolarisation. Based on these data, a route to achieve more optimal SABRE performance is defined.
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Affiliation(s)
- Emma V Stanbury
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , York , YO10 5NY UK .
| | - Peter M Richardson
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , York , YO10 5NY UK .
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance , Department of Chemistry , University of York , York , YO10 5NY UK .
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48
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Tickner BJ, John RO, Roy SS, Hart SJ, Whitwood AC, Duckett SB. Using coligands to gain mechanistic insight into iridium complexes hyperpolarized with para-hydrogen. Chem Sci 2019; 10:5235-5245. [PMID: 31191878 PMCID: PMC6540910 DOI: 10.1039/c9sc00444k] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/15/2019] [Indexed: 12/11/2022] Open
Abstract
We report the formation of a series of novel [Ir(H)2(IMes)(α-13C2-carboxyimine)L] complexes in which the identity of the coligand L is varied. When examined with para-hydrogen, complexes in which L is benzylamine or phenethylamine show significant 1H hydride and 13C2 imine enhancements and may exist in 13C2 singlet spin order. Isotopic labeling techniques are used to double 13C2 enhancements (up to 750-fold) and singlet state lifetimes (up to 20 seconds) compared to those previously reported. Exchange spectroscopy and Density Functional Theory are used to investigate the stability and mechanism of rapid hydrogen exchange in these complexes, a process driven by dissociative coligand loss to form a key five coordinate intermediate. When L is pyridine or imidazole, competitive binding to such intermediates leads to novel complexes whose formation, kinetics, behaviour, structure, and hyperpolarization is investigated. The ratio of the observed PHIP enhancements were found to be affected not only by the hydrogen exchange rates but the identity of the coligands. This ligand reactivity is accompanied by decoherence of any 13C2 singlet order which can be preserved by isotopic labeling. Addition of a thiol coligand proved to yield a thiol oxidative addition product which is characterized by NMR and MS techniques. Significant 870-fold 13C enhancements of pyridine can be achieved using the Signal Amplification By Reversible Exchange (SABRE) process when α-carboxyimines are used to block active coordination sites. [Ir(H)2(IMes)(α-13C2-carboxyimine)L] therefore acts as unique sensors whose 1H hydride chemical shifts and corresponding hyperpolarization levels are indicative of the identity of a coligand and its binding strength.
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Affiliation(s)
- Ben J Tickner
- Center for Hyperpolarization in Magnetic Resonance (CHyM) , University of York , Heslington , York , YO10 5NY , UK .
| | - Richard O John
- Center for Hyperpolarization in Magnetic Resonance (CHyM) , University of York , Heslington , York , YO10 5NY , UK .
| | - Soumya S Roy
- Center for Hyperpolarization in Magnetic Resonance (CHyM) , University of York , Heslington , York , YO10 5NY , UK .
| | - Sam J Hart
- Department of Chemistry , University of York , Heslington , York , YO10 5DD , UK
| | - Adrian C Whitwood
- Department of Chemistry , University of York , Heslington , York , YO10 5DD , UK
| | - Simon B Duckett
- Center for Hyperpolarization in Magnetic Resonance (CHyM) , University of York , Heslington , York , YO10 5NY , UK .
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49
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Semenova O, Richardson PM, Parrott AJ, Nordon A, Halse ME, Duckett SB. Reaction Monitoring Using SABRE-Hyperpolarized Benchtop (1 T) NMR Spectroscopy. Anal Chem 2019; 91:6695-6701. [PMID: 30985110 PMCID: PMC6892580 DOI: 10.1021/acs.analchem.9b00729] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
![]()
The
conversion of [IrCl(COD)(IMes)] (COD = cis,cis-1,5-cyclooctadiene, IMes = 1,3-bis(2,4,6-trimethyl-phenyl)imidazole-2-ylidene)
in the presence of an excess of para-hydrogen (p-H2) and a substrate (4-aminopyridine (4-AP) or 4-methylpyridine (4-MP)) into [Ir(H)2(IMes)(substrate)3]Cl is monitored by 1H NMR spectroscopy using a benchtop (1 T) spectrometer in conjunction
with the p-H2-based hyperpolarization
technique signal amplification by reversible exchange (SABRE). A series
of single-shot 1H NMR measurements are used to monitor
the chemical changes that take place in solution through the lifetime
of the hyperpolarized response. Non-hyperpolarized high-field 1H NMR control measurements were also undertaken to confirm
that the observed time-dependent changes relate directly to the underlying
chemical evolution. The formation of [Ir(H)2(IMes)(substrate)3]Cl is further linked to the hydrogen isotope exchange (HIE)
reaction, which leads to the incorporation of deuterium into the ortho positions of 4-AP, where the source of
deuterium is the solvent, methanol-d4.
Comparable reaction monitoring results are achieved at both high-field
(9.4 T) and low-field (1 T). It is notable that the low sensitivity
of the benchtop (1 T) NMR enables the use of protio solvents, which when used here allows the effects of catalyst formation
and substrate deuteration to be separated. Collectively, these methods illustrate how low-cost low-field NMR
measurements provide unique insight into a complex catalytic process
through a combination of hyperpolarization and relaxation data.
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Affiliation(s)
- Olga Semenova
- Centre for Hyperpolarisation in Magnetic Resonance, Chemistry , The University of York , York YO10 5NY , U.K
| | - Peter M Richardson
- Centre for Hyperpolarisation in Magnetic Resonance, Chemistry , The University of York , York YO10 5NY , U.K
| | - Andrew J Parrott
- WestCHEM, Department of Pure and Applied Chemistry and CPACT , University of Strathclyde , Glasgow G11XQ , U.K
| | - Alison Nordon
- WestCHEM, Department of Pure and Applied Chemistry and CPACT , University of Strathclyde , Glasgow G11XQ , U.K
| | - Meghan E Halse
- Centre for Hyperpolarisation in Magnetic Resonance, Chemistry , The University of York , York YO10 5NY , U.K
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance, Chemistry , The University of York , York YO10 5NY , U.K
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50
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Pravdivtsev AN, Hövener JB. Simulating Non-linear Chemical and Physical (CAP) Dynamics of Signal Amplification By Reversible Exchange (SABRE). Chemistry 2019; 25:7659-7668. [PMID: 30689237 DOI: 10.1002/chem.201806133] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/18/2019] [Indexed: 01/30/2023]
Abstract
The hyperpolarization of nuclear spins by using parahydrogen (pH2 ) is a fascinating technique that allows spin polarization and thus the magnetic resonance signal to be increased by several orders of magnitude. Entirely new applications have become available. Signal amplification by reversible exchange (SABRE) is a relatively new method that is based on the reversible exchange of a substrate, catalyst and parahydrogen. SABRE is particularly interesting for in vivo medical and industrial applications, such as fast and low-cost trace analysis or continuous signal enhancement. Ever since its discovery, many attempts have been made to model and understand SABRE, with various degrees of simplifications. In this work, we reduced the simplifications further, taking into account non-linear chemical and physical (CAP) dynamics of several multi-spin systems. A master equation was derived and realized using the MOIN open-source software. The effects of different parameters (exchange rates, concentrations, spin-spin couplings) on relaxation and the polarization level have been evaluated and the results provide interesting insights into the mechanism of SABRE.
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Affiliation(s)
- Andrey N Pravdivtsev
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany
| | - Jan-Bernd Hövener
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany
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