1
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Salnikov OG, Trofimov IA, Bender ZT, Trepakova AI, Xu J, Wibbels GL, Shchepin RV, Koptyug IV, Barskiy DA. Parahydrogen-Induced Polarization of 14N Nuclei. Angew Chem Int Ed Engl 2024; 63:e202402877. [PMID: 38523072 DOI: 10.1002/anie.202402877] [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: 02/08/2024] [Revised: 03/22/2024] [Accepted: 03/22/2024] [Indexed: 03/26/2024]
Abstract
Hyperpolarization techniques provide a dramatic increase in sensitivity of nuclear magnetic resonance spectroscopy and imaging. In spite of the outstanding progress in solution-state hyperpolarization of spin-1/2 nuclei, hyperpolarization of quadrupolar nuclei remains challenging. Here, hyperpolarization of quadrupolar 14N nuclei with natural isotopic abundance of >99 % is demonstrated. This is achieved via pairwise addition of parahydrogen to tetraalkylammonium salts with vinyl or allyl unsaturated moieties followed by a subsequent polarization transfer from 1H to 14N nuclei at high magnetic field using PH-INEPT or PH-INEPT+ radiofrequency pulse sequence. Catalyst screening identified water-soluble rhodium complex [Rh(P(m-C6H4SO3Na)3)3Cl] as the most efficient catalyst for hyperpolarization of the substrates under study, providing up to 1.3 % and up to 6.6 % 1H polarization in the cases of vinyl and allyl precursors, respectively. The performance of PH-INEPT and PH-INEPT+ pulse sequences was optimized with respect to interpulse delays, and the resultant experimental dependences were in good agreement with simulations. As a result, 14N NMR signal enhancement of up to 760-fold at 7.05 T (corresponding to 0.15 % 14N polarization) was obtained.
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Affiliation(s)
- Oleg G Salnikov
- International Tomography Center SB RAS, 3 A Institutskaya St., Novosibirsk, 630090, Russia
| | - Ivan A Trofimov
- International Tomography Center SB RAS, 3 A Institutskaya St., Novosibirsk, 630090, Russia
- Current affiliation, Division of Medical Physics, Department of Diagnostic and Interventional Radiology, Faculty of Medicine, University of Freiburg, University Medical Center Freiburg, Freiburg, 79106, Germany
| | - Zachary T Bender
- South Dakota School of Mines & Technology, Rapid City, South Dakota, 57701, United States
| | - Alexandra I Trepakova
- International Tomography Center SB RAS, 3 A Institutskaya St., Novosibirsk, 630090, Russia
| | - Jingyan Xu
- Helmholtz Institute Mainz, GSI Helmholtz Center for Heavy Ion Research GmbH, and, Institute of Physics, Johannes Gutenberg-Universität, Mainz, 55128, Germany
| | - Garrett L Wibbels
- South Dakota School of Mines & Technology, Rapid City, South Dakota, 57701, United States
| | - Roman V Shchepin
- South Dakota School of Mines & Technology, Rapid City, South Dakota, 57701, United States
| | - Igor V Koptyug
- International Tomography Center SB RAS, 3 A Institutskaya St., Novosibirsk, 630090, Russia
| | - Danila A Barskiy
- Helmholtz Institute Mainz, GSI Helmholtz Center for Heavy Ion Research GmbH, and, Institute of Physics, Johannes Gutenberg-Universität, Mainz, 55128, Germany
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2
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Assaf CD, Gui X, Auer AA, Duckett SB, Hövener JB, Pravdivtsev AN. J Coupling Constants of <1 Hz Enable 13C Hyperpolarization of Pyruvate via Reversible Exchange of Parahydrogen. J Phys Chem Lett 2024; 15:1195-1203. [PMID: 38271215 PMCID: PMC10860132 DOI: 10.1021/acs.jpclett.3c02980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Observing pyruvate metabolism in vivo has become a focal point of molecular magnetic resonance imaging. Signal amplification by reversible exchange (SABRE) has recently emerged as a versatile hyperpolarization technique. Tuning of the spin order transfer (SOT) in SABRE is challenging as the small 1H-13C J couplings, in the 13C-pyruvate case, result in SOT being not readily discernible. We demonstrate an experimental method using frequency-selective excitation of parahydrogen-derived polarization SOT sequence (SEPP-SPINEPT); its application led to up to 5700-fold 13C signal gain. In this way, we estimated the lifetime of two Ir-pyruvate SABRE complexes alongside the individual probing of eight small 1H-13C J couplings that connect the hydride protons in these complexes to 1- and 2-13C pyruvate spins, affording values between 0 and 2.69 Hz. Using electronic structure calculations, we define the low-energy structure of the corresponding complexes. Hence, this study demonstrates a novel approach to analyzing the spin topology of short-lived organometallic complexes.
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Affiliation(s)
- 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
| | - Xin Gui
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Alexander A Auer
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Simon B Duckett
- Centre for Hyperpolarization in Magnetic Resonance (CHyM), University of York, Heslington YO10 5NY, U.K
| | - 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
| | - 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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3
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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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4
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Ellermann F, Sirbu A, Brahms A, Assaf C, Herges R, Hövener JB, Pravdivtsev AN. Spying on parahydrogen-induced polarization transfer using a half-tesla benchtop MRI and hyperpolarized imaging enabled by automation. Nat Commun 2023; 14:4774. [PMID: 37553405 PMCID: PMC10409769 DOI: 10.1038/s41467-023-40539-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 07/31/2023] [Indexed: 08/10/2023] Open
Abstract
Nuclear spin hyperpolarization is a quantum effect that enhances the nuclear magnetic resonance signal by several orders of magnitude and has enabled real-time metabolic imaging in humans. However, the translation of hyperpolarization technology into routine use in laboratories and medical centers is hampered by the lack of portable, cost-effective polarizers that are not commercially available. Here, we present a portable, automated polarizer based on parahydrogen-induced hyperpolarization (PHIP) at an intermediate magnetic field of 0.5 T (achieved by permanent magnets). With a footprint of 1 m2, we demonstrate semi-continuous, fully automated 1H hyperpolarization of ethyl acetate-d6 and ethyl pyruvate-d6 to P = 14.4% and 16.2%, respectively, and a 13C polarization of 1-13C-ethyl pyruvate-d6 of P = 7%. The duty cycle for preparing a dose is no more than 1 min. To reveal the full potential of 1H hyperpolarization in an inhomogeneous magnetic field, we convert the anti-phase PHIP signals into in-phase peaks, thereby increasing the SNR by a factor of 5. Using a spin-echo approach allowed us to observe the evolution of spin order distribution in real time while conserving the expensive reagents for reaction monitoring, imaging and potential in vivo usage. This compact polarizer will allow us to pursue the translation of hyperpolarized MRI towards in vivo applications further.
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Affiliation(s)
- Frowin Ellermann
- 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
| | - Aidan Sirbu
- Western University, 1151 Richmond St, London, ON, N6A 3K7, Canada
| | - Arne Brahms
- Otto Diels Institute for Organic Chemistry, Kiel University, Otto- Hahn Platz 4, 24118, Kiel, Germany
| | - Charbel 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
| | - Rainer Herges
- Otto Diels Institute for Organic Chemistry, Kiel University, Otto- Hahn Platz 4, 24118, Kiel, Germany
| | - 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
| | - 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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5
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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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6
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Marshall A, Salhov A, Gierse M, Müller C, Keim M, Lucas S, Parker A, Scheuer J, Vassiliou C, Neumann P, Jelezko F, Retzker A, Blanchard JW, Schwartz I, Knecht S. Radio-Frequency Sweeps at Microtesla Fields for Parahydrogen-Induced Polarization of Biomolecules. J Phys Chem Lett 2023; 14:2125-2132. [PMID: 36802642 DOI: 10.1021/acs.jpclett.2c03785] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Magnetic resonance imaging of 13C-labeled metabolites enhanced by parahydrogen-induced polarization (PHIP) enables real-time monitoring of processes within the body. We introduce a robust, easily implementable technique for transferring parahydrogen-derived singlet order into 13C magnetization using adiabatic radio frequency sweeps at microtesla fields. We experimentally demonstrate the applicability of this technique to several molecules, including some molecules relevant for metabolic imaging, where we show significant improvements in the achievable polarization, in some cases reaching above 60% nuclear spin polarization. Furthermore, we introduce a site-selective deuteration scheme, where deuterium is included in the coupling network of a pyruvate ester to enhance the efficiency of the polarization transfer. These improvements are enabled by the fact that the transfer protocol avoids relaxation induced by strongly coupled quadrupolar nuclei.
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Affiliation(s)
- Alastair Marshall
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
- Institute for Quantum Optics (IQO) and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
| | - Alon Salhov
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
- Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Martin Gierse
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
- Institute for Quantum Optics (IQO) and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
| | | | - Michael Keim
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
| | | | - Anna Parker
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
| | | | | | | | - Fedor Jelezko
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
- Institute for Quantum Optics (IQO) and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
| | - Alex Retzker
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
- Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | | | - Ilai Schwartz
- NVision Imaging Technologies GmbH, 89081 Ulm, Germany
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7
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Saul P, Schröder L, Schmidt AB, Hövener JB. Nanomaterials for hyperpolarized nuclear magnetic resonance and magnetic resonance imaging. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2023:e1879. [PMID: 36781151 DOI: 10.1002/wnan.1879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 01/03/2023] [Accepted: 01/07/2023] [Indexed: 02/15/2023]
Abstract
Nanomaterials play an important role in the development and application of hyperpolarized materials for magnetic resonance imaging (MRI). In this context they can not only act as hyperpolarized materials which are directly imaged but also play a role as carriers for hyperpolarized gases and catalysts for para-hydrogen induced polarization (PHIP) to generate hyperpolarized substrates for metabolic imaging. Those three application possibilities are discussed, focusing on carbon-based materials for the directly imaged particles. An overview over recent developments in all three fields is given, including the early developments in each field as well as important steps towards applications in MRI, such as making the initially developed methods more biocompatible and first imaging experiments with spatial resolution in either phantoms or in vivo studies. Focusing on the important features nanomaterials need to display to be applicable in the MRI context, a wide range of different approaches to that extent is covered, giving the reader a general idea of different possibilities as well as recent developments in those different fields of hyperpolarized magnetic resonance. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.
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Affiliation(s)
- Philip Saul
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein, Kiel University, Kiel, Germany
| | - Leif Schröder
- Division of Translational Molecular Imaging, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany.,Molecular Imaging, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Andreas B Schmidt
- Intergrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan, USA.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Division of Medical Physics, Department of Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jan-Bernd Hövener
- Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein, Kiel University, Kiel, Germany
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8
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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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9
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Chen Z, Li X, Huang Y, Cao S, Chen Z, Lin Y. High-resolution NMR spectroscopy for measuring complex samples based on chemical-shift-difference selection. Phys Chem Chem Phys 2023; 25:999-1005. [PMID: 36533435 DOI: 10.1039/d2cp04279g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
NMR spectroscopy serves as an immensely powerful tool for component assignments and molecular structure elucidations. However, proton NMR spectra are generally trapped with spectral congestion caused by limited frequency differences and complex multiplets. 2D NMR can effectively relieve spectral congestion, but its resolution and acquisition efficiency are restricted by the broad spectral bandwidth. Herein, we introduce an NMR method based on chemical-shift-difference selection by chirp excitation to record high-resolution 2D NMR spectra for extracting coupling correlation networks and multiplet structures, suitable for measurements on complex samples. The performance of the proposed method is illustrated in determining diastereotopic methylene protons, small frequency-difference coupled proton pairs of furanose, pyranose and benzene rings. This study is expected to benefit molecular structure elucidation and composition analysis of complex samples in chemistry, biochemistry and metabonomics.
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Affiliation(s)
- Ziqiao Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
| | - Xueting Li
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
| | - Yuqing Huang
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
| | - Shuohui Cao
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
| | - Zhong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
| | - Yulan Lin
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
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10
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Schmidt AB, de Maissin H, Adelabu I, Nantogma S, Ettedgui J, TomHon P, Goodson BM, Theis T, Chekmenev EY. Catalyst-Free Aqueous Hyperpolarized [1- 13C]Pyruvate Obtained by Re-Dissolution Signal Amplification by Reversible Exchange. ACS Sens 2022; 7:3430-3439. [PMID: 36379005 PMCID: PMC9983023 DOI: 10.1021/acssensors.2c01715] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Despite great successes in oncology, patient outcomes are often still discouraging, and hence the diagnostic imaging paradigm is increasingly shifting toward functional imaging of the pathology to better understand individual disease biology and to personalize therapies. The dissolution Dynamic Nuclear Polarization (d-DNP) hyperpolarization method has enabled unprecedented real-time MRI sensing of metabolism and tissue pH using hyperpolarized [1-13C]pyruvate as a biosensor with great potential for diagnosis and monitoring of cancer patients. However, current d-DNP is expensive and suffers from long hyperpolarization times, posing a substantial translational roadblock. Here, we report the development of Re-Dissolution Signal Amplification By Reversible Exchange (Re-D SABRE), which relies on fast and low-cost hyperpolarization of [1-13C]pyruvate by chemical exchange with parahydrogen at microtesla magnetic fields. [1-13C]pyruvate is precipitated from catalyst-containing methanol using ethyl acetate and rapidly reconstituted in aqueous media. 13C polarization of 9 ± 1% is demonstrated after redissolution in water with residual iridium mass fraction of 8.5 ± 1.5 ppm; further improvement is anticipated via process automation. Re-D SABRE makes hyperpolarized [1-13C]pyruvate biosensor available at a fraction of the cost (<$10,000) and production time (≈1 min) of currently used techniques and makes aqueous hyperpolarized [1-13C]pyruvate "ready" for in vivo applications.
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Affiliation(s)
- Andreas B. Schmidt
- Integrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, Detroit, MI 48202, United States
- 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, Killianstr. 5a, Freiburg 79106, Germany
| | - Henri de Maissin
- 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, Killianstr. 5a, Freiburg 79106, Germany
| | - Isaiah Adelabu
- Integrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, Detroit, MI 48202, United States
| | - Shiraz Nantogma
- Integrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, Detroit, MI 48202, United States
| | - Jessica Ettedgui
- Chemistry and Synthesis Center, National Heart, Lung, Blood Institute, 9800 Medical Center Drive, Building B, Room #2034, Rockville, Maryland 20850, United States
| | - Patrick TomHon
- Department of Chemistry, North Carolina State University, Raleigh, NC, 27606, United States
- Vizma Life Sciences LLC, Durham, NC 27707-3669, United States
| | - Boyd M. Goodson
- School of Chemical & Biomolecular Sciences and Materials Technology Center, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, Raleigh, NC, 27606, United States
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC, 27695, United States
| | - Eduard Y. Chekmenev
- Integrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, Detroit, MI 48202, United States
- Russian Academy of Sciences (RAS), Leninskiy Prospect, 14, 119991 Moscow, Russia
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11
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Parahydrogen-induced polarization and spin order transfer in ethyl pyruvate at high magnetic fields. Sci Rep 2022; 12:19361. [PMID: 36371512 PMCID: PMC9653431 DOI: 10.1038/s41598-022-22347-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/13/2022] [Indexed: 01/10/2023] Open
Abstract
Nuclear magnetic resonance has experienced great advances in developing and translating hyperpolarization methods into procedures for fundamental and clinical studies. Here, we propose the use of a wide-bore NMR for large-scale (volume- and concentration-wise) production of hyperpolarized media using parahydrogen-induced polarization. We discuss the benefits of radio frequency-induced parahydrogen spin order transfer, we show that 100% polarization is theoretically expected for homogeneous B0 and B1 magnetic fields for a three-spin system. Moreover, we estimated that the efficiency of spin order transfer is not significantly reduced when the B1 inhomogeneity is below ± 5%; recommendations for the sample size and RF coils are also given. With the latest breakthrough in the high-yield synthesis of 1-13C-vinyl pyruvate and its deuterated isotopologues, the high-field PHIP-SAH will gain increased attention. Some remaining challenges will be addressed shortly.
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12
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Pravdivtsev AN, Brahms A, Ellermann F, Stamp T, Herges R, Hövener JB. Parahydrogen-induced polarization and spin order transfer in ethyl pyruvate at high magnetic fields. Sci Rep 2022; 12:19361. [PMID: 36371512 DOI: 10.21203/rs.3.rs-1807976/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/13/2022] [Indexed: 05/21/2023] Open
Abstract
Nuclear magnetic resonance has experienced great advances in developing and translating hyperpolarization methods into procedures for fundamental and clinical studies. Here, we propose the use of a wide-bore NMR for large-scale (volume- and concentration-wise) production of hyperpolarized media using parahydrogen-induced polarization. We discuss the benefits of radio frequency-induced parahydrogen spin order transfer, we show that 100% polarization is theoretically expected for homogeneous B0 and B1 magnetic fields for a three-spin system. Moreover, we estimated that the efficiency of spin order transfer is not significantly reduced when the B1 inhomogeneity is below ± 5%; recommendations for the sample size and RF coils are also given. With the latest breakthrough in the high-yield synthesis of 1-13C-vinyl pyruvate and its deuterated isotopologues, the high-field PHIP-SAH will gain increased attention. Some remaining challenges will be addressed shortly.
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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 Kiel, Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany.
| | - Arne Brahms
- Otto Diels Institute for Organic Chemistry, Kiel University, Otto- Hahn Platz 4, 24118, Kiel, Germany
| | - Frowin Ellermann
- 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
| | - Tim Stamp
- Otto Diels Institute for Organic Chemistry, Kiel University, Otto- Hahn Platz 4, 24118, Kiel, Germany
| | - Rainer Herges
- Otto Diels Institute for Organic Chemistry, Kiel University, Otto- Hahn Platz 4, 24118, Kiel, Germany
| | - 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.
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13
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Brahms A, Pravdivtsev AN, Stamp T, Ellermann F, Sönnichsen FD, Hövener J, Herges R. Synthesis of 13 C and 2 H Labeled Vinyl Pyruvate and Hyperpolarization of Pyruvate. Chemistry 2022; 28:e202201210. [PMID: 35905033 PMCID: PMC9804285 DOI: 10.1002/chem.202201210] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Indexed: 01/05/2023]
Abstract
The hyperpolarization of nuclear spins has enabled unique applications in chemistry, biophysics, and particularly metabolic imaging. Parahydrogen-induced polarization (PHIP) offers a fast and cost-efficient way of hyperpolarization. Nevertheless, PHIP lags behind dynamic nuclear polarization (DNP), which is already being evaluated in clinical studies. This shortcoming is mainly due to problems in the synthesis of the corresponding PHIP precursor molecules. The most widely used DNP tracer in clinical studies, particularly for the detection of prostate cancer, is 1-13 C-pyruvate. The ideal derivative for PHIP is the deuterated vinyl ester because the spin physics allows for 100 % polarization. Unfortunately, there is no efficient synthesis for vinyl esters of β-ketocarboxylic acids in general and pyruvate in particular. Here, we present an efficient new method for the preparation of vinyl esters, including 13 C labeled, fully deuterated vinyl pyruvate using a palladium-catalyzed procedure. Using 50 % enriched parahydrogen and mild reaction conditions, a 13 C polarization of 12 % was readily achieved; 36 % are expected with 100 % pH2 . Higher polarization values can be potentially achieved with optimized reaction conditions.
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Affiliation(s)
- Arne Brahms
- Otto Diels Institute for Organic ChemistryKiel UniversityOtto-Hahn-Platz 424118KielGermany
| | - Andrey N. Pravdivtsev
- Section Biomedical ImagingMolecular Imaging North Competence Center (MOIN CC)Department of Radiology and NeuroradiologyUniversity Medical Center KielKiel UniversityAm Botanischen Garten 1424118KielGermany
| | - Tim Stamp
- Otto Diels Institute for Organic ChemistryKiel UniversityOtto-Hahn-Platz 424118KielGermany
| | - Frowin Ellermann
- Section Biomedical ImagingMolecular Imaging North Competence Center (MOIN CC)Department of Radiology and NeuroradiologyUniversity Medical Center KielKiel UniversityAm Botanischen Garten 1424118KielGermany
| | - Frank D. Sönnichsen
- Otto Diels Institute for Organic ChemistryKiel UniversityOtto-Hahn-Platz 424118KielGermany
| | - Jan‐Bernd Hövener
- Section Biomedical ImagingMolecular Imaging North Competence Center (MOIN CC)Department of Radiology and NeuroradiologyUniversity Medical Center KielKiel UniversityAm Botanischen Garten 1424118KielGermany
| | - Rainer Herges
- Otto Diels Institute for Organic ChemistryKiel UniversityOtto-Hahn-Platz 424118KielGermany
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14
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Symmetry Constraints on Spin Order Transfer in Parahydrogen-Induced Polarization (PHIP). Symmetry (Basel) 2022. [DOI: 10.3390/sym14030530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
It is well known that the association of parahydrogen (pH2) with an unsaturated molecule or a transient metalorganic complex can enhance the intensity of NMR signals; the effect is known as parahydrogen-induced polarization (PHIP). During recent decades, numerous methods were proposed for converting pH2-derived nuclear spin order to the observable magnetization of protons or other nuclei of interest, usually 13C or 15N. Here, we analyze the constraints imposed by the topological symmetry of the spin systems on the amplitude of transferred polarization. We find that in asymmetric systems, heteronuclei can be polarized to 100%. However, the amplitude drops to 75% in A2BX systems and further to 50% in A3B2X systems. The latter case is of primary importance for biological applications of PHIP using sidearm hydrogenation (PHIP-SAH). If the polarization is transferred to the same type of nuclei, i.e., 1H, symmetry constraints impose significant boundaries on the spin-order distribution. For AB, A2B, A3B, A2B2, AA’(AA’) systems, the maximum average polarization for each spin is 100%, 50%, 33.3%, 25%, and 0, respectively, (where A and B (or A’) came from pH2). Remarkably, if the polarization of all spins in a molecule is summed up, the total polarization grows asymptotically with ~1.27 and can exceed 2 in the absence of symmetry constraints (where is the number of spins). We also discuss the effect of dipole–dipole-induced pH2 spin-order distribution in heterogeneous catalysis or nematic liquid crystals. Practical examples from the literature illustrate our theoretical analysis.
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15
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Quasi-continuous production of highly hyperpolarized carbon-13 contrast agents every 15 seconds within an MRI system. Commun Chem 2022; 5:21. [PMID: 36697573 PMCID: PMC9814607 DOI: 10.1038/s42004-022-00634-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 01/25/2022] [Indexed: 01/28/2023] Open
Abstract
Hyperpolarized contrast agents (HyCAs) have enabled unprecedented magnetic resonance imaging (MRI) of metabolism and pH in vivo. Producing HyCAs with currently available methods, however, is typically time and cost intensive. Here, we show virtually-continuous production of HyCAs using parahydrogen-induced polarization (PHIP), without stand-alone polarizer, but using a system integrated in an MRI instead. Polarization of ≈2% for [1-13C]succinate-d2 or ≈19% for hydroxyethyl-[1-13C]propionate-d3 was created every 15 s, for which fast, effective, and well-synchronized cycling of chemicals and reactions in conjunction with efficient spin-order transfer was key. We addressed these challenges using a dedicated, high-pressure, high-temperature reactor with integrated water-based heating and a setup operated via the MRI pulse program. As PHIP of several biologically relevant HyCAs has recently been described, this Rapid-PHIP technique promises fast preclinical studies, repeated administration or continuous infusion within a single lifetime of the agent, as well as a prolonged window for observation with signal averaging and dynamic monitoring of metabolic alterations.
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16
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Schmidt AB, Bowers CR, Buckenmaier K, Chekmenev EY, de Maissin H, Eills J, Ellermann F, Glöggler S, Gordon JW, Knecht S, Koptyug IV, Kuhn J, Pravdivtsev AN, Reineri F, Theis T, Them K, Hövener JB. Instrumentation for Hydrogenative Parahydrogen-Based Hyperpolarization Techniques. Anal Chem 2022; 94:479-502. [PMID: 34974698 PMCID: PMC8784962 DOI: 10.1021/acs.analchem.1c04863] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Andreas B. Schmidt
- Department of Radiology – Medical Physics, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Killianstr. 5a, Freiburg 79106, Germany
- German Cancer Consortium (DKTK), partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - C. Russell Bowers
- Department of Chemistry, University of Florida, 2001 Museum Road, Gainesville, Florida 32611, USA
- National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, Florida 32310, USA
| | - Kai Buckenmaier
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Max-Planck-Ring 11, 72076, Tübingen, Germany
| | - Eduard Y. Chekmenev
- Intergrative Biosciences (Ibio), Department of Chemistry, Karmanos Cancer Institute (KCI), Wayne State University, 5101 Cass Ave, Detroit, MI 48202, United States
- Russian Academy of Sciences (RAS), Leninskiy Prospect, 14, 119991 Moscow, Russia
| | - Henri de Maissin
- Department of Radiology – Medical Physics, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Killianstr. 5a, Freiburg 79106, Germany
- German Cancer Consortium (DKTK), partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - James Eills
- Institute for Physics, Johannes Gutenberg University, D-55090 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Helmholtz-Institut Mainz, 55128 Mainz, Germany
| | - Frowin Ellermann
- 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
| | - Stefan Glöggler
- NMR Signal Enhancement Group Max Planck Institutefor Biophysical Chemistry Am Fassberg 11, 37077 Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration of UMG Von-Siebold-Str. 3A, 37075 Göttingen, Germany
| | - Jeremy W. Gordon
- Department of Radiology & Biomedical Imaging, University of California San Francisco, 185 Berry St., San Francisco, CA, 94158, USA
| | | | - Igor V. Koptyug
- International Tomography Center, SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia
| | - Jule Kuhn
- 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
| | - 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
| | - Francesca Reineri
- Dept. Molecular Biotechnology and Health Sciences, Via Nizza 52, University of Torino, Italy
| | - Thomas Theis
- Departments of Chemistry, Physics and Biomedical Engineering, North Carolina State University, Raleigh, NC, 27695, USA
| | - Kolja Them
- 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
| | - 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
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