1
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Li S, Bhattacharya S, Chou CY, Chu M, Chou SC, Tonelli M, Goger M, Yang H, Palmer AG, Cavagnero S. LC-Photo-CIDNP hyperpolarization of biomolecules bearing a quasi-isolated spin pair: Magnetic-Field dependence via a rapid-shuttling device. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 359:107616. [PMID: 38271744 PMCID: PMC10922348 DOI: 10.1016/j.jmr.2023.107616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 12/27/2023] [Accepted: 12/28/2023] [Indexed: 01/27/2024]
Abstract
Liquid-state low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) is an emerging technology tailored to enhance the sensitivity of NMR spectroscopy via LED- or laser-mediated optical irradiation. LC-photo-CIDNP is particularly useful to detect solvent-exposed aromatic residues (Trp, Tyr), either in isolation or within polypeptides and proteins. This study investigates the magnetic-field dependence of the LC-photo-CIDNP of Trp-α-13C-β,β,2,4,5,6,7-d7, a Trp isotopolog bearing a quasi-isolated 1Hα-13Cαspin pair (QISP). We employed a new rapid-shuttling side-illumination field-cycling device that enables ultra-fast (90-120 ms) vertical movements of NMR samples within the bore of a superconducting magnet. Thus, LC-photo-CIDNP hyperpolarization occurs at low field, while hyperpolarized signals are detected at high field (700 MHz). Resonance lineshapes were excellent, and the effect of several fields (1.18-7.08 T range) on hyperpolarization efficiency could be readily explored. Remarkably, unprecedented LC-photo-CIDNP enhancements ε ≅ 1,200 were obtained at 50 MHz (1.18 T), suggesting exciting avenues to hypersensitive LED-enhanced NMR in liquids at low field.
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Affiliation(s)
- Siyu Li
- Dept. of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | | | - Ching-Yu Chou
- Field Cycling Technology LTD., New Taipei City 23444, Taiwan, ROC
| | - Minglee Chu
- Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan, ROC
| | - Shu-Cheng Chou
- Field Cycling Technology LTD., New Taipei City 23444, Taiwan, ROC
| | - Marco Tonelli
- Dept. of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Michael Goger
- New York Structural Biology Center, New York, NY 10027, United States
| | - Hanming Yang
- Dept. of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Arthur G Palmer
- New York Structural Biology Center, New York, NY 10027, United States; Dept. of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, United States
| | - Silvia Cavagnero
- Dept. of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, United States.
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2
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Bernarding J, Bruns C, Prediger I, Mützel M, Plaumann M. Detection of sub-nmol amounts of the antiviral drug favipiravir in 19F MRI using photo-chemically induced dynamic nuclear polarization. Sci Rep 2024; 14:1527. [PMID: 38233411 PMCID: PMC10794400 DOI: 10.1038/s41598-024-51454-4] [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: 06/22/2023] [Accepted: 01/05/2024] [Indexed: 01/19/2024] Open
Abstract
In biological tissues, 19F magnetic resonance (MR) enables the non-invasive, background-free detection of 19F-containing biomarkers. However, the signal-to-noise ratio (SNR) is usually low because biomarkers are typically present at low concentrations. Measurements at low magnetic fields further reduce the SNR. In a proof-of-principal study we applied LED-based photo-chemically induced dynamic nuclear polarization (photo-CIDNP) to amplify the 19F signal at 0.6 T. For the first time, 19F MR imaging (MRI) and spectroscopy (MRS) of a fully biocompatible model system containing the antiviral drug favipiravir has been successfully performed. This fluorinated drug has been used to treat Ebola and COVID-19. Since the partially cyclic reaction scheme for photo-CIDNP allows for multiple data acquisitions, averaging further improved the SNR. The mean signal gain factor for 19F has been estimated to be in the order of 103. An in-plane resolution of 0.39 × 0.39 mm2 enabled the analysis of spatially varying degrees of hyperpolarization. The minimal detectable amount of favipiravir per voxel was estimated to about 500 pmol. The results show that 19F photo-CIDNP is a promising method for the non-invasive detection of suitable 19F-containing drugs and other compounds with very low levels of the substance.
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Affiliation(s)
- J Bernarding
- Institute of Biometry and Medical Informatics, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany.
| | - C Bruns
- Institute of Biometry and Medical Informatics, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - I Prediger
- Institute of Biometry and Medical Informatics, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - M Mützel
- Pure Devices GmbH, 97222, Rimpar, Germany
| | - M Plaumann
- Institute of Biometry and Medical Informatics, Otto-von-Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
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3
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Matysik J, Gerhards L, Theiss T, Timmermann L, Kurle-Tucholski P, Musabirova G, Qin R, Ortmann F, Solov'yov IA, Gulder T. Spin Dynamics of Flavoproteins. Int J Mol Sci 2023; 24:ijms24098218. [PMID: 37175925 PMCID: PMC10179055 DOI: 10.3390/ijms24098218] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/19/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
This short review reports the surprising phenomenon of nuclear hyperpolarization occurring in chemical reactions, which is called CIDNP (chemically induced dynamic nuclear polarization) or photo-CIDNP if the chemical reaction is light-driven. The phenomenon occurs in both liquid and solid-state, and electron transfer systems, often carrying flavins as electron acceptors, are involved. Here, we explain the physical and chemical properties of flavins, their occurrence in spin-correlated radical pairs (SCRP) and the possible involvement of flavin-carrying SCRPs in animal magneto-reception at earth's magnetic field.
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Affiliation(s)
- Jörg Matysik
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Luca Gerhards
- Institut für Physik, Carl von Ossietzky Universität Oldenburg, Carl-von Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
| | - Tobias Theiss
- Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | - Lisa Timmermann
- Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | | | - Guzel Musabirova
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Ruonan Qin
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Frank Ortmann
- TUM School of Natural Sciences, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Ilia A Solov'yov
- Institut für Physik, Carl von Ossietzky Universität Oldenburg, Carl-von Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
- Research Center for Neurosensory Science, Carl von Ossietzky Universität Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
- Center for Nanoscale Dynamics (CENAD), Carl von Ossietzky Universität Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany
| | - Tanja Gulder
- Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany
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4
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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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5
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Li S, Yang H, Hofstetter H, Tonelli M, Cavagnero S. Magnetic-Field Dependence of LC-Photo-CIDNP in the Presence of Target Molecules Carrying a Quasi-Isolated Spin Pair. APPLIED MAGNETIC RESONANCE 2023; 54:59-75. [PMID: 37483563 PMCID: PMC10358788 DOI: 10.1007/s00723-022-01506-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/04/2022] [Accepted: 09/30/2022] [Indexed: 07/25/2023]
Abstract
NMR spectroscopy is well known for its superb resolution, especially at high applied magnetic field. However, the sensitivity of this technique is very low. Liquid-state low-concentration photo-chemically-induced dynamic nuclear polarization (LC-photo-CIDNP) is a promising emerging methodology capable of enhancing NMR sensitivity in solution. LC-photo-CIDNP works well on solvent-exposed Trp and Tyr residues, either in isolation or within proteins. This study explores the magnetic-field dependence of the LC-photo-CIDNP experienced by two tryptophan isotopologs in solution upon in situ LED-mediated optical irradiation. Out of the two uniformly 13C,15N-labeled Trp (Trp-U-13C,15N) and Trp-α-13C-β,β,2,4,5,6,7-d7 species employed here, only the latter bears a quasi-isolated 1Hα-13Cα spin pair. Computer simulations of the predicted polarization due to geminate recombination of both species display a roughly bell-shaped field dependence. However, while Trp-U-13C,15N is predicted to show a maximum at ca. 500 MHz (11.7 T) and a fairly weak field dependence, Trp-α-13C-β,β,2,4,5,6,7-d7 is expected to display a much sharper field dependence accompanied by a dramatic polarization increase at lower field (ca. 200 MHz, 4.7 T). Experimental LC-photo-CIDNP studies on both Trp isotopologs at 1μM concentration, performed at selected fields, are consistent with the theoretical predictions. In summary, this study highlights the prominent field-dependence of LC-photo-CIDNP enhancements (ε ) experienced by Trp isotopologs bearing a quasi-isolated spin pair.
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Affiliation(s)
- Siyu Li
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, Wisconsin, 53706, USA
| | - Hanming Yang
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, Wisconsin, 53706, USA
| | - Heike Hofstetter
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, Wisconsin, 53706, USA
| | - Marco Tonelli
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin, 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, Wisconsin, 53706, USA
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6
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Yang H, Li S, Mickles CA, Guzman-Luna V, Sugisaki K, Thompson CM, Dang HH, Cavagnero S. Selective Isotope Labeling and LC-Photo-CIDNP Enable NMR Spectroscopy at Low-Nanomolar Concentration. J Am Chem Soc 2022; 144:11608-11619. [PMID: 35700317 DOI: 10.1021/jacs.2c01809] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
NMR spectroscopy is a powerful tool to investigate molecular structure and dynamics. The poor sensitivity of this technique, however, limits its ability to tackle questions requiring dilute samples. Low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) is an optically enhanced NMR technology capable of addressing the above challenge by increasing the detection limit of aromatic amino acids in solution up to 1000-fold, either in isolation or within proteins. Here, we show that the absence of NMR-active nuclei close to a magnetically active site of interest (e.g., the structurally diagnostic 1Hα-13Cα pair of amino acids) is expected to significantly increase LC-photo-CIDNP hyperpolarization. Then, we exploit the spin-diluted tryptophan isotopolog Trp-α-13C-β,β,2,4,5,6,7-d7 and take advantage of the above prediction to experimentally achieve a ca 4-fold enhancement in NMR sensitivity over regular LC-photo-CIDNP. This advance enables the rapid (within seconds) detection of 20 nM concentrations or the molecule of interest, corresponding to a remarkable 3 ng detection limit. Finally, the above Trp isotopolog is amenable to incorporation within proteins and is readily detectable at a 1 μM concentration in complex cell-like media, including Escherichia coli cell-free extracts.
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Affiliation(s)
- Hanming Yang
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Siyu Li
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Clayton A Mickles
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Valeria Guzman-Luna
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Kenji Sugisaki
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.,JST PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Clayton M Thompson
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Hung H Dang
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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7
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Sheberstov KF, Chuchkova L, Hu Y, Zhukov IV, Kiryutin AS, Eshtukov AV, Cheshkov DA, Barskiy DA, Blanchard JW, Budker D, Ivanov KL, Yurkovskaya AV. Photochemically Induced Dynamic Nuclear Polarization of Heteronuclear Singlet Order. J Phys Chem Lett 2021; 12:4686-4691. [PMID: 33979166 DOI: 10.1021/acs.jpclett.1c00503] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Photochemically induced dynamic nuclear polarization (photo-CIDNP) is a method to hyperpolarize nuclear spins using light. In most cases, CIDNP experiments are performed in high magnetic fields and the sample is irradiated by light inside a nuclear magnetic resonance (NMR) spectrometer. Here we demonstrate photo-CIDNP hyperpolarization generated in the Earth's magnetic field and under zero- to ultralow-field (ZULF) conditions. Irradiating a sample containing tetraphenylporphyrin and para-benzoquinone for several seconds with light-emitting diodes produces strong hyperpolarization of 1H and 13C nuclear spins, enhancing the NMR signals more than 200 times. The hyperpolarized spin states at the Earth's field and in ZULF are different. In the latter case, the state corresponds to the singlet order between scalar-coupled 1H-13C nuclear spins. This state has a longer lifetime than the state hyperpolarized at Earth's field. The method is simple and cost-efficient and should be applicable to many molecular systems known to exhibit photo-CIDNP, including amino acids and nucleotides.
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Affiliation(s)
- Kirill F Sheberstov
- Institut für Physik, Johannes Gutenberg Universität-Mainz, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
| | - Liubov Chuchkova
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
- Faculté des Sciences Mirande, Université de Bourgogne, Dijon 21078, France
| | - Yinan Hu
- Institut für Physik, Johannes Gutenberg Universität-Mainz, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
| | - Ivan V Zhukov
- International Tomography Center SB RAS, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Alexey S Kiryutin
- International Tomography Center SB RAS, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Artur V Eshtukov
- State Scientific Research Institute of Chemistry and Technology of Organoelement Compounds, Moscow 105118, Russia
| | - Dmitry A Cheshkov
- State Scientific Research Institute of Chemistry and Technology of Organoelement Compounds, Moscow 105118, Russia
| | - Danila A Barskiy
- Institut für Physik, Johannes Gutenberg Universität-Mainz, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
| | - John W Blanchard
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
| | - Dmitry Budker
- Institut für Physik, Johannes Gutenberg Universität-Mainz, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Helmholtz-Institut Mainz, 55128 Mainz, Germany
- University of California, Berkeley, California 94720-7300, United States
| | - Konstantin L Ivanov
- International Tomography Center SB RAS, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Alexandra V Yurkovskaya
- International Tomography Center SB RAS, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
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8
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Matysik J, Ding Y, Kim Y, Kurle P, Yurkovskaya A, Ivanov K, Alia A. Photo-CIDNP in Solid State. APPLIED MAGNETIC RESONANCE 2021; 53:521-537. [PMID: 33840910 PMCID: PMC8021640 DOI: 10.1007/s00723-021-01322-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 05/27/2023]
Abstract
Photo-CIDNP (photo-chemically induced dynamic nuclear polarization) refers to nuclear polarization created by the spin-chemical evolution of spin-correlated radical pairs (SCRPs). This phenomenon occurs in gases, liquids and solids. Based on the solid-state photo-CIDNP effect observed under magic-angle spinning (MAS), photo-CIDNP MAS NMR has been developed as analytical method. Here we report the origin, the theory and the state of the art of this method.
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Affiliation(s)
- Jörg Matysik
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Yonghong Ding
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Yunmi Kim
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | - Patrick Kurle
- Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, Germany
| | | | - Konstantin Ivanov
- International Tomography Center, Institutskaya, 630090 Novosibirsk, Russia
| | - A. Alia
- Institut für Medizinische Physik und Biophysik, Universität Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
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9
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Torres F, Sobol A, Greenwald J, Renn A, Morozova O, Yurkovskaya A, Riek R. Molecular features toward high photo-CIDNP hyperpolariztion explored through the oxidocyclization of tryptophan. Phys Chem Chem Phys 2021; 23:6641-6650. [PMID: 33710192 DOI: 10.1039/d0cp06068b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Photo-chemically induced dynamic nuclear polarization (photo-CIDNP) is a promising solution to the inherent lack of sensitivity in NMR spectroscopy. It is particularly interesting in biological systems since it operates in water, at room temperature, and it can be repeated if the bleaching of the system can be controlled. However, the photo-CIDNP signal enhancement is well below those of other hyperpolarization techniques. While DNP, PHIP, and SABRE reach polarization enhancements of 103 to 104-fold, photo-CIDNP enhancement is typically only one order of magnitude for 1H and two orders of magnitude for 13C in the amino-acids tryptophan and tyrosine. Here we report on a photo-oxidation product of tryptophan that is strongly photo-CIDNP active under continuous wave light irradiation. In conjunction with the dye Atto Thio 12, a 1H signal enhancement of 120-fold was observed on a 600 MHz spectrometer, while at 200 MHz the enhancement was 380-fold. These enhancements in signal to noise correspond to a reduction in measurement time of 14 400-fold and 144 400-fold, respectively. The enhancement for 13C is estimated to be over 1200-fold at 600 MHz which corresponds to an impressive measurement time reduction of 1 440 000-fold. This photo-CIDNP active oxidation product of tryptophan has been identified to be 3α-hydroxypyrroloindole. The reasons for its improved signal enhancement compared to tryptophan have been further investigated.
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Affiliation(s)
- Felix Torres
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
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10
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Yang H, Mecha MF, Goebel CP, Cavagnero S. Enhanced nuclear-spin hyperpolarization of amino acids and proteins via reductive radical quenchers. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 324:106912. [PMID: 33524671 PMCID: PMC7925436 DOI: 10.1016/j.jmr.2021.106912] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
Low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) has recently emerged as an effective tool for the hyperpolarization of aromatic amino acids in solution, either in isolation or within proteins. One factor limiting the maximum achievable signal-to-noise ratio in LC-photo-CIDNP is the progressive degradation of the target molecule and photosensitizer upon long-term optical irradiation. Fortunately, this effect does not cause spectral distortions but leads to a progressively smaller signal buildup upon long-term data-collection (e.g. 500 nM tryptophan on a 600 MHz spectrometer after ca. 200 scans). Given that it is generally desirable to minimize the extent of photodamage, we report that low-μM amounts of the reductive radical quenchers vitamin C (VC, i.e., ascorbic acid) or 2-mercaptoethylamine (MEA) enable LC-photo-CIDNP data to be acquired for significantly longer time than ever possible before. This approach increases the sensitivity of LC-photo-CIDNP by more than 100%, with larger enhancement factors achieved in experiments involving more transients. Our results are consistent with VC and MEA acting primarily by reducing transient free radicals of the NMR molecule of interest, thus attenuating the extent of photodamage. The benefits of this reductive radical-quencher approach are highlighted by the ability to collect long-term high-resolution 2D 1H-13C LC-photo-CIDNP data on a dilute sample of the drkN SH3 protein (5 μM).
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Affiliation(s)
- Hanming Yang
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave, Madison, WI 53706, USA
| | - Miranda F Mecha
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave, Madison, WI 53706, USA
| | - Collin P Goebel
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave, Madison, WI 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave, Madison, WI 53706, USA.
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11
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Skubi KL, Swords WB, Hofstetter H, Yoon TP. LED-NMR Monitoring of an Enantioselective Catalytic [2+2] Photocycloaddition. CHEMPHOTOCHEM 2020; 4:685-690. [PMID: 34532566 PMCID: PMC8443221 DOI: 10.1002/cptc.202000094] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Indexed: 01/08/2023]
Abstract
We report that an NMR spectrometer equipped with a high-power LED light source can be used to study a fast enantioselective photocatalytic [2+2] cycloaddition. While traditional ex situ applications of NMR provide considerable information on reaction mechanisms, they are often ineffective for observing fast reactions. Recently, motivated by renewed interest in organic photochemistry, several approaches have been reported for in situ monitoring of photochemical reactions. These previously disclosed methods, however, have rarely been applied to rapid (<5 min) photochemical reactions. Furthermore, these approaches have not previously been used to interrogate the mechanisms of photocatalytic energy-transfer reactions. In the present work, we describe our experimental setup and demonstrate its utility by determining a phenomenological rate law for a model photocatalytic energy-transfer cycloaddition reaction.
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Affiliation(s)
- Kazimer L Skubi
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
- Department of Chemistry, Skidmore College, 815 North Broadway, Saratoga Springs, NY (USA)
| | - Wesley B Swords
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
| | - Heike Hofstetter
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
| | - Tehshik P Yoon
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI (USA)
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12
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Yang H, Hofstetter H, Cavagnero S. Fast-pulsing LED-enhanced NMR: A convenient and inexpensive approach to increase NMR sensitivity. J Chem Phys 2019; 151:245102. [PMID: 31893873 DOI: 10.1063/1.5131452] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) has recently emerged as a powerful technology for the detection of aromatic amino acids and proteins in solution in the low-micromolar to nanomolar concentration range. LC-photo-CIDNP is typically carried out in the presence of high-power lasers, which are costly and maintenance-heavy. Here, we show that LC-photo-CIDNP can be performed with light-emitting diodes (LEDs), which are inexpensive and much less cumbersome than lasers, laser diodes, flash lamps, or other light sources. When nuclear magnetic resonance (NMR) sample concentration is within the low-micromolar to nanomolar range, as in LC-photo-CIDNP, replacement of lasers with LEDs leads to no losses in sensitivity. We also investigate the effect of optical-fiber thickness and compare excitation rate constants of an Ar ion laser (488 nm) and a 466 nm LED, taking LED emission bandwidths into account. In addition, importantly, we develop a novel pulse sequence (13C RASPRINT) to perform ultrarapid LC-photo-CIDNP data collection. Remarkably, 13C RASPRINT leads to 4-fold savings in data collection time. The latter advance relies on the fact that photo-CID nuclear hyperpolarization does not suffer from the longitudinal-relaxation recovery requirements of conventional NMR. Finally, we combine both the above improvements, resulting in facile and rapid (≈16 s-2.5 min) collection of 1 and 2D NMR data on aromatic amino acids and proteins in solution at nanomolar to low micromolar concentration.
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Affiliation(s)
- Hanming Yang
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, USA
| | - Heike Hofstetter
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, USA
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13
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Sobol A, Torres F, Aicher A, Renn A, Riek R. Atto Thio 12 as a promising dye for photo-CIDNP. J Chem Phys 2019; 151:234201. [DOI: 10.1063/1.5128575] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Alexander Sobol
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Felix Torres
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Anatol Aicher
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Alois Renn
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Roland Riek
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
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14
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Nitschke P, Lokesh N, Gschwind RM. Combination of illumination and high resolution NMR spectroscopy: Key features and practical aspects, photochemical applications, and new concepts. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:86-134. [PMID: 31779887 DOI: 10.1016/j.pnmrs.2019.06.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/04/2019] [Accepted: 06/04/2019] [Indexed: 06/10/2023]
Abstract
In the last decade, photochemical and photocatalytic applications have developed into one of the dominant research fields in chemistry. However, mechanistic investigations to sustain this enormous progress are still relatively sparse and in high demand by the photochemistry community. UV/Vis spectroscopy and EPR spectroscopy have been the main spectroscopic tools to study the mechanisms of photoreactions due to their higher time resolution and sensitivity. On the other hand, application of NMR in photosystems has been mainly restricted to photo-CIDNP, since the initial photoexcitation was thought to be the single key to understand photoinduced reactions. In 2015 the Gschwind group showcased the possibility that different reaction pathways could occur from the same photoexcited state depending on the reaction conditions by using in situ LED illumination NMR. This was the starting point to push the active participation of NMR in photosystems to its full potential, including reaction profiling, structure determination of intermediates, downstream mechanistic studies, dark pathways, intermediate sequencing with CEST etc. Following this, multiple studies using in situ illumination NMR have been reported focusing on mechanistic investigations in photocatalysis, photoswitches, and polymerizations. The recent increased popularity of this technique can be attributed to the simplicity of the experimental setup and the availability of low cost, high power LEDs. Here, we review the development of experimental design, applications and new concepts of illuminated NMR. In the first part, we describe the development of different designs of NMR illumination apparatus, illuminating from the bottom/side/top/inside, and discuss their pros and cons for specific applications. Furthermore, we address LASERs and LEDs as different light sources as well as special cases such as UVNMR(-illumination), FlowNMR, NMR on a Chip etc. To complete the discussion on experimental apparatus, the advantages and disadvantages of in situ LED illumination NMR versus ex situ illumination NMR are described. The second part of this review discusses different facets of applications of inside illumination experiments. It highlights newly revealed mechanistic and structural information and ideas in the fields of photocatalyis, photoswitches and photopolymerization. Finally, we present new concepts and methods based on the combination of NMR and illumination such as sensitivity enhancement, chemical pump probes, experimental access to transition state combinations and NMR actinometry. Overall this review presents NMR spectroscopy as a complementary tool to UV/Vis spectroscopy in mechanistic and structural investigations of photochemical processes. The review is presented in a way that is intended to assist the photochemistry and photocatalysis community in adopting and understanding this astonishingly powerful in situ LED illumination NMR method for their investigations on a daily basis.
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Affiliation(s)
- Philipp Nitschke
- Organic Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | | | - Ruth M Gschwind
- Organic Chemistry, University of Regensburg, 93040 Regensburg, Germany.
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15
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Yang H, Cavagnero S. Improved sensitivity of laser-enhanced 1H α- 13C α-correlation via suppression of C α-C' scalar-coupling evolution. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 307:106572. [PMID: 31445479 PMCID: PMC7416423 DOI: 10.1016/j.jmr.2019.106572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 08/06/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
Low-concentration photochemically induced dynamic polarization (LC-photo-CIDNP) enables the spectroscopic analysis of biomolecules containing the amino acids Trp and Tyr at sub-micromolar concentration in solution. Typical LC-photo-CIDNP pulse sequences involving 1H-13C correlation, however, perform well in the case of aromatic resonances but display a relatively poor signal-to-noise ratio for 13Cα and 13Cβ resonances. Here, we develop a novel pulse sequence denoted as 13C perturbation-recovered selective-pulse photo-CINDP enhanced reverse INEPT, or 13C PRESPRINT, tailored to the LC-photo-CIDNP analysis of 1H-13Cα pairs. Our method, which is based on full suppression of 1-bond Cα-C' scalar-coupling evolution during the constant-time delay, results into a sensitivity improvement by a factor of 2. The enhanced performance of this pulse sequence enabled us to improve the analysis of LC-photo-CIDNP laser-power dependence at very low (200 nM) sample concentration. An improved theoretical model, developed to quantitatively describe this laser-power dependence, shows excellent agreement with our 13C PRESPRINT experimental data.
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Affiliation(s)
- Hanming Yang
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, WI 53706, USA.
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16
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Laser- and cryogenic probe-assisted NMR enables hypersensitive analysis of biomolecules at submicromolar concentration. Proc Natl Acad Sci U S A 2019; 116:11602-11611. [PMID: 31142651 DOI: 10.1073/pnas.1820573116] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Solution-state NMR typically requires 100 μM to 1 mM samples. This limitation prevents applications to mass-limited and aggregation-prone target molecules. Photochemically induced dynamic nuclear polarization was adapted to data collection on low-concentration samples by radiofrequency gating, enabling rapid 1D NMR spectral acquisition on aromatic amino acids and proteins bearing aromatic residues at nanomolar concentration, i.e., a full order of magnitude below other hyperpolarization techniques in liquids. Both backbone H1-C13 and side-chain resonances were enhanced, enabling secondary and tertiary structure analysis of proteins with remarkable spectral editing, via the 13C PREPRINT pulse sequence. Laser-enhanced 2D NMR spectra of 5 μM proteins at 600 MHz display 30-fold better S/N than conventional 2D data collected at 900 MHz. Sensitivity enhancements achieved with this technology, denoted as low-concentration photo-CIDNP (LC-photo-CIDNP), depend only weakly on laser intensity, highlighting the opportunity of safer and more cost-effective hypersensitive NMR applications employing low-power laser sources.
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17
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Serrer K, Matt C, Sokolov M, Kacprzak S, Schleicher E, Weber S. Application of commercially available fluorophores as triplet spin probes in EPR spectroscopy. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1608379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Kerstin Serrer
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Clemens Matt
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Monja Sokolov
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Sylwia Kacprzak
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Erik Schleicher
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Stefan Weber
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
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18
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Morozova OB, Ivanov KL. Time-Resolved Chemically Induced Dynamic Nuclear Polarization of Biologically Important Molecules. Chemphyschem 2018; 20:197-215. [DOI: 10.1002/cphc.201800566] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/11/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Olga B. Morozova
- International Tomography Center; Institutskaya 3a 630090 Novosibirsk Russia
- Novosibirsk State University; Pirogova 2 630090 Novosibirsk Russia
| | - Konstantin L. Ivanov
- International Tomography Center; Institutskaya 3a 630090 Novosibirsk Russia
- Novosibirsk State University; Pirogova 2 630090 Novosibirsk Russia
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19
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Morozova OB, Fishman NN, Yurkovskaya AV. Kinetics of Reversible Protonation of Transient Neutral Guanine Radical in Neutral Aqueous Solution. Chemphyschem 2018; 19:2696-2702. [PMID: 29978943 DOI: 10.1002/cphc.201800539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Indexed: 11/11/2022]
Abstract
Time-resolved chemically induced dynamic nuclear polarization (TR-CIDNP) is applied to follow transformation of the short-lived neutral guanine radical into a secondary guanine radical by its protonation, presumably at position N7. In the initial step the photoreaction of guanosine-5'-monophosphate (GMP) with triplet excited 3,3',4,4'-tetracarboxy benzophenone (TCBP) leads to formation of the neutral radical G(-H). . The evidence of the radical conversion is based on the inversion of CIDNP sign for TCBP and GMP protons on the microsecond timescale as a result of the change in magnetic resonance parameters in the pairs of TCBP and GMP radicals due to structural changes of the GMP radical. Acceleration of the CIDNP sign change upon addition of phosphate (proton donor) confirms that the radical transformation responsible for the observed CIDNP kinetics is protonation of the neutral guanine radical with formation of the newly characterized cation radical, (G.+ )'. From the full analysis of the pH-dependent CIDNP kinetics, the protonation and deprotonation behaviour is quantitatively characterized, giving pKa =8.0±0.2 of the cation radical (G.+ )'.
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Affiliation(s)
- Olga B Morozova
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Natalya N Fishman
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
| | - Alexandra V Yurkovskaya
- International Tomography Center, Institutskaya 3a, 630090, Novosibirsk, Russia.,Novosibirsk State University, Pirogova 2, 630090, Novosibirsk, Russia
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20
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Okuno Y, Cavagnero S. Effect of heavy atoms on photochemically induced dynamic nuclear polarization in liquids. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 286:172-187. [PMID: 29274568 PMCID: PMC5767533 DOI: 10.1016/j.jmr.2017.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Revised: 11/18/2017] [Accepted: 12/02/2017] [Indexed: 06/07/2023]
Abstract
Given its short hyperpolarization time (∼10-6 s) and mostly non-perturbative nature, photo-chemically induced dynamic nuclear polarization (photo-CIDNP) is a powerful tool for sensitivity enhancement in nuclear magnetic resonance. In this study, we explore the extent of 1H-detected 13C nuclear hyperpolarization that can be gained via photo-CIDNP in the presence of small-molecule additives containing a heavy atom. The underlying rationale for this methodology is the well-known external-heavy-atom (EHA) effect, which leads to significant enhancements in the intersystem-crossing rate of selected photosensitizer dyes from photoexcited singlet to triplet. We exploited the EHA effect upon addition of moderate amounts of halogen-atom-containing cosolutes. The resulting increase in the transient triplet-state population of the photo-CIDNP sensitizer fluorescein resulted in a significant increase in the nuclear hyperpolarization achievable via photo-CIDNP in liquids. We also explored the internal-heavy-atom (IHA) effect, which is mediated by halogen atoms covalently incorporated into the photosensitizer dye. Widely different outcomes were achieved in the case of EHA and IHA, with EHA being largely preferable in terms of net hyperpolarization.
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Affiliation(s)
- Yusuke Okuno
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Ave., Madison, WI 53706, USA.
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