1
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Korzeczek MC, Dagys L, Müller C, Tratzmiller B, Salhov A, Eichhorn T, Scheuer J, Knecht S, Plenio MB, Schwartz I. Towards a unified picture of polarization transfer - pulsed DNP and chemically equivalent PHIP. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 362:107671. [PMID: 38614057 DOI: 10.1016/j.jmr.2024.107671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 03/30/2024] [Accepted: 04/03/2024] [Indexed: 04/15/2024]
Abstract
Nuclear spin hyperpolarization techniques, such as dynamic nuclear polarization (DNP) and parahydrogen-induced polarization (PHIP), have revolutionized nuclear magnetic resonance and magnetic resonance imaging. In these methods, a readily available source of high spin order, either electron spins in DNP or singlet states in hydrogen for PHIP, is brought into close proximity with nuclear spin targets, enabling efficient transfer of spin order under external quantum control. Despite vast disparities in energy scales and interaction mechanisms between electron spins in DNP and nuclear singlet states in PHIP, a pseudo-spin formalism allows us to establish an intriguing equivalence. As a result, the important low-field polarization transfer regime of PHIP can be mapped onto an analogous system equivalent to pulsed-DNP. This establishes a correspondence between key polarization transfer sequences in PHIP and DNP, facilitating the transfer of sequence development concepts. This promises fresh insights and significant cross-pollination between DNP and PHIP polarization sequence developers.
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Affiliation(s)
- Martin C Korzeczek
- Institute of Theoretical Physics and IQST, Albert-Einstein Allee 11, Ulm University, 89081, Ulm, Germany
| | | | | | - Benedikt Tratzmiller
- Institute of Theoretical Physics and IQST, Albert-Einstein Allee 11, Ulm University, 89081, Ulm, Germany; Carl Zeiss MultiSEM GmbH, 73447, Oberkochen, Germany
| | - Alon Salhov
- NVision Imaging Technologies GmbH, 89081, Ulm, Germany; Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, 91904, Givat Ram, Israel
| | - Tim Eichhorn
- NVision Imaging Technologies GmbH, 89081, Ulm, Germany
| | | | | | - Martin B Plenio
- Institute of Theoretical Physics and IQST, Albert-Einstein Allee 11, Ulm University, 89081, Ulm, Germany.
| | - Ilai Schwartz
- NVision Imaging Technologies GmbH, 89081, Ulm, Germany.
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2
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Mandzhieva I, Adelabu I, Nantogma S, Chekmenev EY, Theis T. Delivering Robust Proton-Only Sensing of Hyperpolarized [1,2- 13C 2]-Pyruvate Using Broad-Spectral-Range Nuclear Magnetic Resonance Pulse Sequences. ACS Sens 2023; 8:4101-4110. [PMID: 37948125 PMCID: PMC10883757 DOI: 10.1021/acssensors.3c01296] [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] [Indexed: 11/12/2023]
Abstract
Hyperpolarized [1-13C]pyruvate is the leading hyperpolarized injectable contrast agent and is currently under evaluation in clinical trials for molecular imaging of metabolic diseases, including cardiovascular disease and cancer. One aspect limiting broad scalability of the technique is that hyperpolarized 13C MRI requires specialized 13C hardware and software that are not generally available on clinical MRI scanners, which employ proton-only detection. Here, we present an approach that uses pulse sequences to transfer 13C hyperpolarization to methyl protons for detection of the 13C-13C pyruvate singlet, employing proton-only excitation and detection only. The new pulse sequences are robust to the B1 and B0 magnetic field inhomogeneities. The work focuses on singlet-to-magnetization (S2M) and rotor-synchronized (R) pulses, both relying on trains of hard pulses with broad spectral width coverage designed to effectively transform hyperpolarized 13C2-singlet hyperpolarization to 1H polarization on the CH3 group of [1,2-13C2]pyruvate. This approach may enable a broader adoption of hyperpolarized MRI as a molecular imaging technique.
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Affiliation(s)
- Iuliia Mandzhieva
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27606, United States
| | - Isaiah Adelabu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Shiraz Nantogma
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
| | - Eduard Y. Chekmenev
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States
- Biosciences (Ibio), Wayne State University, Detroit, Michigan 48202, United States
- Karmanos Cancer Institute (KCI), Detroit, Michigan 48201, United States
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27606, United States
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27606, United States
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina 27695, United States
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3
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Lu J, Jerschow A, Korenchan DE. Selective filtration of NMR signals arising from weakly- and strongly-coupled spin systems. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 354:107529. [PMID: 37572586 DOI: 10.1016/j.jmr.2023.107529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/14/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful technique for analyzing chemical and biological systems. However, in complex solutions with similar molecular components, NMR signals can overlap, making it challenging to distinguish and quantify individual species. In this paper, we introduce new spectral editing sequences that exploit the differences in nuclear spin interactions (J-couplings) between weakly- and strongly-coupled two-spin systems. These sequences selectively attenuate or nullify undesired spin magnetization while they preserve the desired signals, resulting in simplified NMR spectra and potentially facilitating single-species imaging applications. We demonstrate the effectiveness of our approach using a 31P spectral filtration method on a model system of nicotinamide dinucleotide (NAD), which exists in oxidized (NAD+) and reduced (NADH) forms. The presented sequences are robust to field inhomogeneity, do not require additional sub-spectra, and retain a significant portion of the original signal.
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Affiliation(s)
- Jiaqi Lu
- Department of Chemistry, New York University, 100 Washington Square East, Room 710, New York, 10003, NY, USA
| | - Alexej Jerschow
- Department of Chemistry, New York University, 100 Washington Square East, Room 710, New York, 10003, NY, USA
| | - David E Korenchan
- Department of Chemistry, New York University, 100 Washington Square East, Room 710, New York, 10003, NY, USA; Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, 75 3rd Ave., Room 1400A, Charlestown, 02129, MA, USA.
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4
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Sonnefeld A, Razanahoera A, Pelupessy P, Bodenhausen G, Sheberstov K. Long-lived states of methylene protons in achiral molecules. SCIENCE ADVANCES 2022; 8:eade2113. [PMID: 36459545 PMCID: PMC10936052 DOI: 10.1126/sciadv.ade2113] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/19/2022] [Indexed: 06/17/2023]
Abstract
In nuclear magnetic resonance (NMR), the lifetimes of long-lived states (LLSs) are exquisitely sensitive to their environment. However, the number of molecules where such states can be excited has hitherto been rather limited. Here, it is shown that LLSs can be readily excited in many common molecules that contain two or more neighboring CH2 groups. Accessing such LLSs does not require any isotopic enrichment, nor does it require any stereogenic centers to lift the chemical equivalence of CH2 protons. LLSs were excited in a variety of metabolites, neurotransmitters, vitamins, amino acids, and other molecules. One can excite LLSs in several different molecules simultaneously. In combination with magnetic resonance imaging, LLSs can reveal a contrast upon noncovalent binding of ligands to macromolecules. This suggests new perspectives to achieve high-throughput parallel drug screening by NMR.
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Affiliation(s)
- Anna Sonnefeld
- Department of chemistry, École Normale Supérieure, PSL University, Paris, France
| | - Aiky Razanahoera
- Department of chemistry, École Normale Supérieure, PSL University, Paris, France
| | - Philippe Pelupessy
- Department of chemistry, École Normale Supérieure, PSL University, Paris, France
| | | | - Kirill Sheberstov
- Department of chemistry, École Normale Supérieure, PSL University, Paris, France
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5
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Yang X, Hu KR, Xin JX, Li YX, Yang G, Wei DX, Yao YF. Multiple-targeting NMR signal selection by optimal control of nuclear spin singlet. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 338:107188. [PMID: 35338893 DOI: 10.1016/j.jmr.2022.107188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/24/2022] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
Selectively probing specific molecules in complex mixtures with nuclear magnetic resonance promises new insights into molecular structures or molecular interaction. Such a study often can be further facilitated when two or more objects in chemical moieties of interest can be precisely targeted. Herein, we proposed a novel method to implement the multiple-targeting signal selection by optimal control of the spin singlets of two or more targeted spin systems from one or more molecules. This method can endow the conventional nuclear magnetic resonance (NMR), magnetic resonance image (MRI) and magnetic resonance spectrum (MRS) with the multiple-targeting signal selectivity to selectively probe several targeted molecules and/or chemical groups simultaneously.
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Affiliation(s)
- Xue Yang
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Kai-Rui Hu
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Jia-Xiang Xin
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Yu-Xiao Li
- Department of Radiology, Shanghai Changhai Hospital, The Second Military Medical University, Shanghai 200433, China
| | - Guang Yang
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Da-Xiu Wei
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China.
| | - Ye-Feng Yao
- Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China.
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6
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Glöggler S, Yang S, Saul P, Mamone S, Kaltschnee L. Bimodal fluorescence/magnetic resonance molecular probes with extended spin lifetimes. Chemistry 2021; 28:e202104158. [PMID: 34854145 PMCID: PMC9302690 DOI: 10.1002/chem.202104158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Indexed: 11/12/2022]
Abstract
Bimodal molecular probes combining nuclear magnetic resonance (NMR) and fluorescence have been widely studied in basic science, as well as clinical research. The investigation of spin phenomena holds promise to broaden the scope of available probes allowing deeper insights into physiological processes. Herein, a class of molecules with a bimodal character with respect to fluorescence and nuclear spin singlet states is introduced. Singlet states are NMR silent but can be probed indirectly. Symmetric, perdeuterated molecules, in which the singlet states can be populated by vanishingly small electron‐mediated couplings (below 1 Hz) are reported. The lifetimes of these states are an order of magnitude longer than the longitudinal relaxation times and up to four minutes at 7 T. Moreover, these molecules show either aggregation induced emission (AIE) or aggregation caused quenching (ACQ) with respect to their fluorescence. In the latter case, the existence of excited dimers, which are proposed to use in a switchable manner in combination with the quenching of nuclear spin singlet states, is observed
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Affiliation(s)
- Stefan Glöggler
- Max-Planck-Institute for Biophysical Chemistry, NMR Signal Enhancement Group, Am Fassberg 11, 37077, Göttingen, GERMANY
| | - Shengjun Yang
- Max-Planck-Institute for Biophysical Chemistry: Max-Planck-Institut fur biophysikalische Chemie, NMR Signal Enhancement, GERMANY
| | - Philip Saul
- Max-Planck-Institute for Biophysical Chemistry: Max-Planck-Institut fur biophysikalische Chemie, NMR Singal Enhancement, GERMANY
| | - Salvatore Mamone
- Max-Planck-Institute for Biophysical Chemistry: Max-Planck-Institut fur biophysikalische Chemie, NMR Signal Enhancement, GERMANY
| | - Lukas Kaltschnee
- Max-Planck-Institute for Biophysical Chemistry: Max-Planck-Institut fur biophysikalische Chemie, NMR Signal Enhancement, GERMANY
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7
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Saul P, Yang S, Mamone S, Opazo F, Meyer A, Rizzoli SO, Glöggler S. Exotic nuclear spin behavior in dendritic macromolecules. Phys Chem Chem Phys 2021; 23:26349-26355. [PMID: 34792046 DOI: 10.1039/d1cp04483d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dendrimers are a class of branched, highly symmetric macromolecules that have been shown to be useful for a vast number of different applications. Potential uses as fluorescence sensors, in catalysis and perhaps most importantly in medical applications as drug delivery systems or cytotoxica have been proposed. Herein we report on an exotic behaviour of the nuclear spins in a dendritic macromolecule in the presence of different paramagnetic ions. We show that the stability of the long lived nuclear singlet state, is affected by the presence of Cu(II), whereas other ions did not have any influence at all. This effect could not be observed in the case of a simple tripeptide, in which the nuclear singlet stability was influenced by all investigated paramagnetic ions, a potentially useful effect in the development of Cu(II) selective probes. By adding a fluorescent marker to our molecule we could show that the nuclear singlet multimer (NUSIMER) is taken up by living cells. Furthermore we were able to show that nuclear singlet state NMR can be used to investigate the NUSIMER in the presence of living cells, showing that an application in in vivo NMR can be feasible.
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Affiliation(s)
- Philip Saul
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. .,Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Straße 3A, 37075 Göttingen, Germany
| | - Shengjun Yang
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. .,Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Straße 3A, 37075 Göttingen, Germany
| | - Salvatore Mamone
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. .,Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Straße 3A, 37075 Göttingen, Germany
| | - Felipe Opazo
- Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Straße 3A, 37075 Göttingen, Germany.,Institute for Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Andreas Meyer
- Research Group Electron Paramagnetic Resonance, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Silvio O Rizzoli
- Institute for Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Stefan Glöggler
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. .,Center for Biostructural Imaging of Neurodegeneration, Von-Siebold-Straße 3A, 37075 Göttingen, Germany
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8
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Bengs C, Dagys L, Moustafa GAI, Whipham JW, Sabba M, Kiryutin AS, Ivanov KL, Levitt MH. Nuclear singlet relaxation by chemical exchange. J Chem Phys 2021; 155:124311. [PMID: 34598559 DOI: 10.1063/5.0066182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The population imbalance between nuclear singlet states and triplet states of strongly coupled spin-1/2 pairs, also known as nuclear singlet order, is well protected against several common relaxation mechanisms. We study the nuclear singlet relaxation of 13C pairs in aqueous solutions of 1,2-13C2 squarate over a range of pH values. The 13C singlet order is accessed by introducing 18O nuclei in order to break the chemical equivalence. The squarate dianion is in chemical equilibrium with hydrogen-squarate (SqH-) and squaric acid (SqH2) characterized by the dissociation constants pK1 = 1.5 and pK2 = 3.4. Surprisingly, we observe a striking increase in the singlet decay time constants TS when the pH of the solution exceeds ∼10, which is far above the acid-base equilibrium points. We derive general rate expressions for chemical-exchange-induced nuclear singlet relaxation and provide a qualitative explanation of the TS behavior of the squarate dianion. We identify a kinetic contribution to the singlet relaxation rate constant, which explicitly depends on kinetic rate constants. Qualitative agreement is achieved between the theory and the experimental data. This study shows that infrequent chemical events may have a strong effect on the relaxation of nuclear singlet order.
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Affiliation(s)
- Christian Bengs
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Laurynas Dagys
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Gamal A I Moustafa
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - James W Whipham
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Mohamed Sabba
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | | | | | - Malcolm H Levitt
- School of Chemistry, University of Southampton, Southampton, United Kingdom
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9
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Korenchan DE, Lu J, Levitt MH, Jerschow A. 31P nuclear spin singlet lifetimes in a system with switchable magnetic inequivalence: experiment and simulation. Phys Chem Chem Phys 2021; 23:19465-19471. [PMID: 34525141 DOI: 10.1039/d1cp03085j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
31P NMR spectroscopy and the study of nuclear spin singlet relaxation phenomena are of interest in particular due to the importance of phosphorus-containing compounds in physiology. We report the generation and measurement of relaxation of 31P singlet order in a chemically equivalent but magnetically inequivalent case. Nuclear magnetic resonance singlet state lifetimes of 31P pairs have heretofore not been reported. Couplings between 1H and 31P nuclei lead to magnetic inequivalence and serve as a mechanism of singlet state population conversion within this molecule. We show that in this molecule singlet relaxation occurs at a rate significantly faster than spin-lattice relaxation, and that anticorrelated chemical shift anisotropy can account for this observation. Calculations of this mechanism, with the help of molecular dynamics simulations and ab initio calculations, provide excellent agreement with the experimental findings. This study could provide guidance for the study of 31P singlets within other compounds, including biomolecules.
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Affiliation(s)
| | - Jiaqi Lu
- Department of Chemistry, New York University, New York, NY, USA.
| | | | - Alexej Jerschow
- Department of Chemistry, New York University, New York, NY, USA.
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10
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Abstract
Nuclear long-lived spin states represent spin density operator configurations that are exceptionally well protected against spin relaxation phenomena. Their long-lived character is exploited in a variety of Nuclear Magnetic Resonance (NMR) techniques. Despite the growing importance of long-lived spin states in modern NMR, strategies for their identification have changed little over the last decade. The standard approach heavily relies on a chain of group theoretical arguments. In this paper, we present a more streamlined method for the calculation of such configurations. Instead of focusing on the symmetry properties of the relaxation superoperator, we focus on its corresponding relaxation algebra. This enables us to analyze long-lived spin states with Lie algebraic methods rather than group theoretical arguments. We show that the centralizer of the relaxation algebra forms a basis for the set of long-lived spin states. The characterization of the centralizer, on the other hand, does not rely on any special symmetry arguments, and its calculation is straightforward. We outline a basic algorithm and illustrate advantages by considering long-lived spin states for some spin-1/2 pairs and rapidly rotating methyl groups.
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Affiliation(s)
- Christian Bengs
- School of Chemistry, School of Chemistry, University of Southampton, University Road, Southampton, SO17 1BJ United Kingdom
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11
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Teleanu F, Sadet A, Vasos PR. Symmetry versus entropy: Long-lived states and coherences. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2021; 122:63-75. [PMID: 33632418 DOI: 10.1016/j.pnmrs.2020.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/28/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
In recent years, new molecular symmetry-based approaches for magnetic resonance have been invented. The implications of these discoveries will be significant for molecular imaging via magnetic resonance, in vitro as well as in vivo, for quantum computing and for other fields. Since the initial observation in 2004 in Southampton that effective spin symmetry can be instilled in a molecule during magnetic resonance experiments, spin states that are resilient to relaxation mechanisms have been increasingly used. Most of these states are related to the nuclear singlet in a pair of J-coupled spins. Tailored relaxation rate constants for magnetization became available in molecules of different sizes and structures, as experimental developments broadened the scope of symmetry-adapted spin states. The ensuing access to timescales longer than the classically-attained ones by circa one order of magnitude allows the study of processes such as slow diffusion or slow exchange that were previously beyond reach. Long-lived states formed by differences between populations of singlets and triplets have overcome the limitations imposed by longitudinal relaxation times (T1) by factors up to 40. Long-lived coherences formed by superpositions of singlets and triplets have overcome the limit of classical transverse coherence (T2) by a factor 9. We present here an overview of the development and applications of long-lived states (LLS) and long-lived coherences (LLC's) and considerations on future perspectives.
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Affiliation(s)
- Florin Teleanu
- Extreme Light Infrastructure - Nuclear Physics ELI-NP, Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering IFIN-HH, 30 Reactorului Street, RO-077125 Bucharest-Măgurele, Romania; College for Advanced Performance Studies, Babeș-Bolyai University, Mihail Kogălniceanu Street 1, Cluj-Napoca, Romania; Interdisciplinary School of Doctoral Studies, University of Bucharest, B-dul Regina Elisabeta, Bucharest, Romania
| | - Aude Sadet
- Extreme Light Infrastructure - Nuclear Physics ELI-NP, Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering IFIN-HH, 30 Reactorului Street, RO-077125 Bucharest-Măgurele, Romania
| | - Paul R Vasos
- Extreme Light Infrastructure - Nuclear Physics ELI-NP, Laser Gamma Experiments Department (LGED), "Horia Hulubei" National Institute for Physics and Nuclear Engineering IFIN-HH, 30 Reactorului Street, RO-077125 Bucharest-Măgurele, Romania; Interdisciplinary School of Doctoral Studies, University of Bucharest, B-dul Regina Elisabeta, Bucharest, Romania.
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12
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Wei D, Xin J, Hu K, Yao Y. Preparation of Long-Lived States in a Multi-Spin System by Using an Optimal Control Method. Chemphyschem 2020; 21:1326-1330. [PMID: 32249498 DOI: 10.1002/cphc.202000038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/30/2020] [Indexed: 01/19/2023]
Abstract
The lifetime Ts of a long-lived nuclear spin state (LLS) could be much longer than the longitudinal order T1 . Many spin systems were used to produce long-lived states, including two or more homonuclear spins that couple to each other. For multiple homonuclear spins with rather small chemical shift difference, normally it is difficult to selectively control the spins and then to prepare a LLS. Herein, we present a scheme that prepares different spin orders in a multi-spin system by using optimal control and numerical calculation. By experimentally measuring the lifetime of the states, we find that for a three-spin physical system, although there are many forms of state combinations with different spin orders, each component has its own lifetime.
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Affiliation(s)
- Daxiu Wei
- Shanghai Key Laboratory of Magnetic Resonance College of Physics and Electronic Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, P. R. China
| | - Jiaxiang Xin
- Shanghai Key Laboratory of Magnetic Resonance College of Physics and Electronic Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, P. R. China
| | - Kairui Hu
- Shanghai Key Laboratory of Magnetic Resonance College of Physics and Electronic Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, P. R. China
| | - Yefeng Yao
- Shanghai Key Laboratory of Magnetic Resonance College of Physics and Electronic Science, East China Normal University, North Zhongshan Road 3663, Shanghai, 200062, P. R. China
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13
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Generating and sustaining long-lived spin states in 15N, 15N'-azobenzene. Sci Rep 2019; 9:20161. [PMID: 31882901 PMCID: PMC6934830 DOI: 10.1038/s41598-019-56734-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 12/11/2019] [Indexed: 11/23/2022] Open
Abstract
Long-Lived spin States (LLSs) hold a great promise for sustaining non-thermal spin order and investigating various slow processes by Nuclear Magnetic Resonance (NMR) spectroscopy. Of special interest for such application are molecules containing nearly equivalent magnetic nuclei, which possess LLSs even at high magnetic fields. In this work, we report an LLS in trans-15N,15N′-azobenzene. The singlet state of the 15N spin pair exhibits a long-lived character. We solve the challenging problem of generating and detecting this LLS and further increase the LLS population by converting the much higher magnetization of protons into the 15N singlet spin order. As far as the longevity of this spin order is concerned, various schemes have been tested for sustaining the LLS. Lifetimes of 17 minutes have been achieved at 16.4 T, a value about 250 times longer than the longitudinal relaxation time of 15N in this magnetic field. We believe that such extended relaxation times, along with the photochromic properties of azobenzene, which changes conformation upon light irradiation and can be hyperpolarized by using parahydrogen, are promising for designing new experiments with photo-switchable long-lived hyperpolarization.
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14
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Rodin BA, Sheberstov KF, Kiryutin AS, Brown LJ, Brown RCD, Sabba M, Levitt MH, Yurkovskaya AV, Ivanov KL. Fast destruction of singlet order in NMR experiments. J Chem Phys 2019; 151:234203. [PMID: 31864263 DOI: 10.1063/1.5131730] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Bogdan A. Rodin
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Kirill F. Sheberstov
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia
- Johannes Gutenberg-Universitat, Helmholtz Institute Mainz, Mainz 55099, Germany
| | - Alexey S. Kiryutin
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Lynda J. Brown
- Department of Chemistry, Southampton University, Southampton SO17 1BJ, United Kingdom
| | - Richard C. D. Brown
- Department of Chemistry, Southampton University, Southampton SO17 1BJ, United Kingdom
| | - Mohamed Sabba
- Department of Chemistry, Southampton University, Southampton SO17 1BJ, United Kingdom
| | - Malcolm H. Levitt
- Department of Chemistry, Southampton University, Southampton SO17 1BJ, United Kingdom
| | - Alexandra V. Yurkovskaya
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Konstantin L. Ivanov
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Novosibirsk 630090, Russia
- Novosibirsk State University, Novosibirsk 630090, Russia
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15
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Appelt S, Kentner A, Lehmkuhl S, Blümich B. From LASER physics to the para-hydrogen pumped RASER. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:1-32. [PMID: 31779878 DOI: 10.1016/j.pnmrs.2019.05.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 05/18/2019] [Indexed: 06/10/2023]
Abstract
The properties of the LASER with respect to self-organization are compared with the key features of the p-H2 pumped RASER. According to LASER theory the equations of motion for the LASER can be derived from the enslaving principle, i.e. the slowest-changing order parameter (the light field in the resonator) enslaves the rapidly relaxing atomic degrees of freedom. Likewise, it is shown here that the equations of motion for the p-H2 pumped RASER result from a set of order parameters, where the transverse magnetization of the RASER-active spin states enslaves the electromagnetic modes. The consequences are striking for nuclear magnetic resonance (NMR) spectroscopy, since long-lasting multi-mode RASER oscillations enable unprecedented spectroscopic resolution down to the micro-Hertz regime. Based on the theory for multi-mode RASER operation we analyze the conditions that reveal either the collapse of the entire NMR spectrum, the occurrence of self-organized frequency-combs, or RASER spectra which reflect the J-coupled network of the molecule. Certain RASER experiments involving the protons of 15N pyridine or 3-picoline molecules pumped with p-H2 via SABRE (Signal Amplification By Reversible Exchange) show either a single RASER oscillation in the time domain, giant RASER pulses or a complex RASER beat pattern. The corresponding 1H spectra consist of one narrow line, equidistant narrow lines (frequency-comb), or highly resolved lines reporting NMR properties, respectively. Numerous applications in the areas of material sciences, fundamental physics and medicine involving high precision sensors for magnetic fields, rotational motions or molecular structures become feasible.
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Affiliation(s)
- S Appelt
- Central Institute for Engineering, Electronics and Analytics - Electronic Systems (ZEA-2), Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
| | - A Kentner
- Central Institute for Engineering, Electronics and Analytics - Electronic Systems (ZEA-2), Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - S Lehmkuhl
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, D-52056 Aachen, Germany
| | - B Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, D-52056 Aachen, Germany
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16
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Levitt MH. Long live the singlet state! JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 306:69-74. [PMID: 31307892 DOI: 10.1016/j.jmr.2019.07.029] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 03/30/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
The field of long-lived states in NMR is reviewed. The relationship of long-lived-state phenomena to those associated with spin isomerism is discussed. A brief overview is given of key developments in the field of long-lived states, including chemical symmetry-switching, the role of magnetic equivalence and magnetic inequivalence, long-lived coherences, hyperpolarized NMR involving long-lived states, quantum-rotor-induced polarization, and parahydrogen-induced hyperpolarization. Current application areas of long-lived states are reviewed, and a peer into the crystal ball reveals future developments in the field.
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Affiliation(s)
- Malcolm H Levitt
- School of Chemistry, University of Southampton, University Road, SO17 1BJ Southampton, UK.
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17
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18
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Ariyasingha NM, Salnikov OG, Kovtunov KV, Kovtunova LM, Bukhtiyarov VI, Goodson BM, Rosen MS, Koptyug IV, Gelovani JG, Chekmenev EY. Relaxation Dynamics of Nuclear Long-Lived Spin States in Propane and Propane-d 6 Hyperpolarized by Parahydrogen. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2019; 123:11734-11744. [PMID: 31798763 PMCID: PMC6890414 DOI: 10.1021/acs.jpcc.9b01538] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report a systematic study of relaxation dynamics of hyperpolarized (HP) propane and HP propane-d6 prepared by heterogeneous pairwise parahydrogen addition to propylene and propylene-d6 respectively. Long-lived spin states (LLS) created for these molecules at the low magnetic field of 0.0475 T were employed for this study. The parahydrogen-induced overpopulation of a HP propane LLS decays exponentially with time constant (TLLS) approximately 3-fold greater than the corresponding T1 values. Both TLLS and T1 increase linearly with propane pressure in the range from 1 atm (the most biomedically relevant conditions for pulmonary MRI) to 5 atm. The TLLS value of HP propane gas at 1 atm is ~3 s. Deuteration of the substrate (propylene-d6) yields hyperpolarized propane-d6 gas with TLLS values approximately 20% shorter than those of hyperpolarized fully protonated propane gas, indicating that deuteration does not benefit the lifetime of the LLS HP state. The use of pH2 or Xe/N2 buffering gas during heterogeneous hydrogenation reaction (leading to production of 100% HP propane (no buffering gas) versus 43% HP propane gas (with 57% buffering gas) composition mixtures) results in (i) no significant changes in T1, (ii) decrease of TLLS values (by 35±7% and 8±7% respectively); and (iii) an increase of the polarization levels of HP propane gas with a propane concentration decrease (by 1.6±0.1-fold and 1.4±0.1-fold respectively despite the decrease in TLLS, which leads to disproportionately greater polarization losses during HP gas transport). Moreover, we demonstrate the feasibility of HP propane cryo-collection (which can be potentially useful for preparing larger amounts of concentrated HP propane, when buffering gas is employed), and TLLS of liquefied HP propane reaches 14.7 seconds, which is greater than the TLLS value of HP propane gas at any pressure studied. Finally, we have explored the utility of using a partial Spin-Lock Induced Crossing (SLIC) radio frequency (RF) pulse sequence for converting the overpopulated LLS into observable 1H nuclear magnetization at low magnetic field. We find that (i) the bulk of the overpopulated LLS is retained even when the optimal or near-optimal values of SLIC pulse duration are employed, and (ii) the overpopulated LLS of propane is also relatively immune to strong RF pulses-thereby, indicating that LLS is highly suitable as a spin-polarization reservoir in the context of NMR/MRI detection applications. The presented findings may be useful for improving the levels of polarization of HP propane produced by HET-PHIP via the use of an inert buffer gas; increasing the lifetime of the HP state during preparation and storage; and developing efficient approaches for ultrafast MR imaging of HP propane in the context of biomedical applications of HP propane gas, including its potential use as an inhalable contrast agent.
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Affiliation(s)
- Nuwandi M. Ariyasingha
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan, 48202, United States
| | - Oleg G. Salnikov
- International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Kirill V. Kovtunov
- International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Larisa M. Kovtunova
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
- Boreskov Institute of Catalysis SB RAS, 5 Acad. Lavrentiev Pr., Novosibirsk, 630090, Russia
| | - Valerii I. Bukhtiyarov
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
- Boreskov Institute of Catalysis SB RAS, 5 Acad. Lavrentiev Pr., Novosibirsk, 630090, Russia
| | - Boyd M. Goodson
- Department of Chemistry and Biochemistry and Materials Technology Center, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Matthew S. Rosen
- Massachusetts General Hospital/Athinoula A. Martinos Center for Biomedical Imaging, Boston, Massachusetts 02129, United States
| | - Igor V. Koptyug
- International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Juri G. Gelovani
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan, 48202, United States
| | - Eduard Y. Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan, 48202, United States
- Russian Academy of Sciences, Leninskiy Prospekt 14, Moscow, 119991, Russia
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Elliott SJ, Stevanato G. Homonuclear ADAPT: A general preparation route to long-lived nuclear singlet order. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 301:49-55. [PMID: 30851665 DOI: 10.1016/j.jmr.2019.02.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/27/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
We introduce a simple strategy to access and readout nuclear singlet order based on the alternate repetition of hard pulses and delays. We demonstrate the general applicability of the method by accessing nuclear singlet order in spin systems characterized by diverse coupling regimes. We show that the method is highly efficient in the strong-coupling and chemical equivalence regimes, and can overcome some limitations of other well-established and more elaborated pulse sequences. A simulation package is provided which allows the determination of pulse sequence parameters.
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Affiliation(s)
- Stuart J Elliott
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Gabriele Stevanato
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Batochime, CH-1015 Lausanne, Switzerland.
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20
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Elliott SJ, Bengs C, Brown LJ, Hill-Cousins JT, O'Leary DJ, Pileio G, Levitt MH. Nuclear singlet relaxation by scalar relaxation of the second kind in the slow-fluctuation regime. J Chem Phys 2019; 150:064315. [PMID: 30769970 DOI: 10.1063/1.5074199] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The singlet state of nuclear spin-1/2 pairs is protected against many common relaxation mechanisms. Singlet order, which is defined as the population difference between the nuclear singlet and triplet states, usually decays more slowly than the nuclear magnetization. Nevertheless, some decay mechanisms for nuclear singlet order persist. One such mechanism is called scalar relaxation of the second kind (SR2K) and involves the relaxation of additional nuclei ("third spins") which have scalar couplings to the spin-1/2 pair. This mechanism requires a difference between the couplings of at least one third spin with the two members of the spin-1/2 pair, and depends on the longitudinal relaxation time of the third spin. The SR2K mechanism of nuclear singlet relaxation has previously been examined in the case where the relaxation rate of the additional spins is on the time scale of the nuclear Larmor frequency. In this paper, we consider a different regime, in which the longitudinal relaxation of the third spins is on a similar time scale to the J-coupling between the members of the spin pair. This regime is often encountered when the spin-1/2 pair has scalar couplings to nearby deuterium nuclei. We show that the SR2K mechanism may be suppressed in this regime by applying a radiofrequency field which is resonant either with the members of the spin pair, or with the third spins. These phenomena are analyzed theoretically and by numerical simulations, and demonstrated experimentally on a diester of [13C2, 2H2]-labeled fumarate in solution.
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Affiliation(s)
- S J Elliott
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - C Bengs
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - L J Brown
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - J T Hill-Cousins
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - D J O'Leary
- Department of Chemistry, Pomona College, Claremont, California 91711, USA
| | - G Pileio
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - M H Levitt
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
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21
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Yang S, McCormick J, Mamone S, Bouchard L, Glöggler S. Nuclear Spin Singlet States in Photoactive Molecules: From Fluorescence/NMR Bimodality to a Bimolecular Switch for Spin Singlet States. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201814198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shengjun Yang
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
| | - Jeffrey McCormick
- Department of Chemistry and Biochemistry University of California at Los Angeles Los Angeles CA 90095-1569 USA
| | - Salvatore Mamone
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
| | - Louis‐S. Bouchard
- Department of Chemistry and Biochemistry University of California at Los Angeles Los Angeles CA 90095-1569 USA
| | - Stefan Glöggler
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
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22
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Yang S, McCormick J, Mamone S, Bouchard L, Glöggler S. Nuclear Spin Singlet States in Photoactive Molecules: From Fluorescence/NMR Bimodality to a Bimolecular Switch for Spin Singlet States. Angew Chem Int Ed Engl 2019; 58:2879-2883. [DOI: 10.1002/anie.201814198] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 12/27/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Shengjun Yang
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
| | - Jeffrey McCormick
- Department of Chemistry and Biochemistry University of California at Los Angeles Los Angeles CA 90095-1569 USA
| | - Salvatore Mamone
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
| | - Louis‐S. Bouchard
- Department of Chemistry and Biochemistry University of California at Los Angeles Los Angeles CA 90095-1569 USA
| | - Stefan Glöggler
- Research Group for NMR Signal Enhancement, Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration Von-Siebold-Str. 3A 37075 Göttingen Germany
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23
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Saul P, Mamone S, Glöggler S. Nuclear singlet multimers (NUSIMERs) with long-lived singlet states. Chem Sci 2019; 10:413-417. [PMID: 30746089 PMCID: PMC6334717 DOI: 10.1039/c8sc02831a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/24/2018] [Indexed: 01/13/2023] Open
Abstract
Magnetic resonance (NMR) is a powerful tool in chemical analysis, structure determination and in medical diagnostics. Developing novel biological sensors for this field holds promise to better investigate protein structures or target diseases more efficiently. Herein, we explore nuclear spin singlet states in dendritic macromolecules as a platform molecule to develop stimuli responsive probes. We have developed a nuclear singlet multimer (NUSIMER) based on a generation 5 poly(amidoamine) dendrimer (PAMAM) which contains on average about 90 accessible nuclear spin singlet states with lifetimes up to 10-fold longer than the T 1 relaxation times (up to 10 seconds T s vs. T 1 < 0.5 seconds) in a single molecule. We demonstrate little influence on the singlet lifetime in phosphate buffer (H2O) and a high viscosity gel environment in the presence of paramagnetic oxygen. Additionally, we demonstrate an increase in singlet lifetime upon the release of a protective chemical moiety from the NUSIMER following a stimulus, whereby no change in longitudinal relaxation time is observed. The robustness and change in singlet lifetime of the NUSIMER holds promise for the development of a novel type of biosensors.
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Affiliation(s)
- Philip Saul
- 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-Straße 3A , 37075 Göttingen , Germany
| | - Salvatore Mamone
- 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-Straße 3A , 37075 Göttingen , 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-Straße 3A , 37075 Göttingen , Germany
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24
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Zhukov IV, Kiryutin AS, Yurkovskaya AV, Ivanov KL. Assessment of heteronuclear long-lived states at ultralow magnetic fields. Phys Chem Chem Phys 2019; 21:18188-18194. [DOI: 10.1039/c9cp03719e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A study of long-lived spin states in hetero-nuclear spin systems is presented.
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Affiliation(s)
- Ivan V. Zhukov
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Alexey S. Kiryutin
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | | | - Konstantin L. Ivanov
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
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25
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Erriah B, Elliott SJ. Experimental evidence for the role of paramagnetic oxygen concentration on the decay of long-lived nuclear spin order. RSC Adv 2019; 9:23418-23424. [PMID: 35514498 PMCID: PMC9067289 DOI: 10.1039/c9ra03748a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 07/09/2019] [Indexed: 11/21/2022] Open
Abstract
The sensitivity of longitudinal magnetization and singlet order to relaxation from dissolved paramagnetic oxygen sources in solution is investigated experimentally.
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Affiliation(s)
- Bryan Erriah
- School of Chemistry
- University of Southampton
- Southampton SO17 1BJ
- UK
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26
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Blechta V, Sýkora J. Proton detection of carbon-carbon couplings in symmetrical molecules: Analytical explanation, SYMONA pulse sequence. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 298:107-114. [PMID: 30544014 DOI: 10.1016/j.jmr.2018.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/26/2018] [Accepted: 12/03/2018] [Indexed: 06/09/2023]
Abstract
The approach to the measurement of one-bond indirect spin-spin coupling constants between equivalent nuclei was revisited. The analytical formulas for development of the density matrix of strongly coupled symmetrical HC-C'H' spin systems were derived and the optimal duration of polarization delay in the original 2QHMBC pulse sequence is discussed. Based on the analytical formulas a new version of a robust indirect detection experiment, called SYMONA (SYmmetrical MOlecules Natural Abundance double-quantum experiment), was proposed for carbon-carbon coupling constants detection in symmetrical molecules. Additionally, application of the SYMONA experiment to more complicated spin systems than isolated HC-C'H' is discussed.
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Affiliation(s)
- Vratislav Blechta
- Institute of Chemical Process Fundamentals of the CAS, v. v. i., Rozvojova 135, 165 02 Prague 6, Czech Republic.
| | - Jan Sýkora
- Institute of Chemical Process Fundamentals of the CAS, v. v. i., Rozvojova 135, 165 02 Prague 6, Czech Republic
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27
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Elliott SJ, Kadeřávek P, Brown LJ, Sabba M, Glöggler S, O'Leary DJ, Brown RCD, Ferrage F, Levitt MH. Field-cycling long-lived-state NMR of 15N2 spin pairs. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1543906] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Stuart J. Elliott
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Pavel Kadeřávek
- Laboratoire des Biomolécules, Département de Chimie, Ecole Normale Supérieure, Paris, France
| | - Lynda J. Brown
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Mohamed Sabba
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Stefan Glöggler
- Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration of UMG, Göttingen, Germany
| | - Daniel J. O'Leary
- Department of Chemistry, Pomona College, Claremont, California, United States of America
| | | | - Fabien Ferrage
- Laboratoire des Biomolécules, Département de Chimie, Ecole Normale Supérieure, Paris, France
| | - Malcolm H. Levitt
- School of Chemistry, University of Southampton, Southampton, United Kingdom
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28
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Player TC, Hore PJ. Posner qubits: spin dynamics of entangled Ca 9(PO 4) 6 molecules and their role in neural processing. J R Soc Interface 2018; 15:20180494. [PMID: 30381344 PMCID: PMC6228494 DOI: 10.1098/rsif.2018.0494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/08/2018] [Indexed: 11/12/2022] Open
Abstract
It has been suggested that 31P nuclear spins in Ca9(PO4)6 molecules could form the basis of a quantum mechanism for neural processing in the brain. A fundamental requirement of this proposal is that spins in different Ca9(PO4)6 molecules can become entangled and remain so for periods (estimated at many hours) that hugely exceed typical 31P spin relaxation times. Here, we consider the coherent and incoherent spin dynamics of Ca9(PO4)6 arising from dipolar and scalar spin-spin interactions and derive an upper bound of 37 min on the entanglement lifetime under idealized physiological conditions. We argue that the spin relaxation in Ca9(PO4)6 is likely to be much faster than this estimate.
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Affiliation(s)
- Thomas C Player
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
| | - P J Hore
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
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29
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Ivanov KL, Bodenhausen G. Generating para-water from para-hydrogen: A Gedankenexperiment. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 292:48-52. [PMID: 29778834 DOI: 10.1016/j.jmr.2018.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 05/06/2018] [Accepted: 05/07/2018] [Indexed: 06/08/2023]
Abstract
A novel conceptual approach is described that is based on the transfer of hyperpolarization from para-hydrogen in view of generating a population imbalance between the two spin isomers of H2O. The approach is analogous to SABRE (Signal Amplification By Reversible Exchange) and makes use of the transfer of spin order from para-hydrogen to H2O in a hypothetical organometallic complex. The spin order transfer is expected to be most efficient at avoided level crossings. The highest achievable enrichment levels of para- and ortho-water are discussed.
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Affiliation(s)
- Konstantin L Ivanov
- International Tomography Center SB RAS, Institutskaya 3a, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russia.
| | - Geoffrey Bodenhausen
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
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30
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Rodin BA, Kiryutin AS, Yurkovskaya AV, Ivanov KL, Yamamoto S, Sato K, Takui T. Using optimal control methods with constraints to generate singlet states in NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 291:14-22. [PMID: 29626735 DOI: 10.1016/j.jmr.2018.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/06/2018] [Accepted: 03/09/2018] [Indexed: 06/08/2023]
Abstract
A method is proposed for optimizing the performance of the APSOC (Adiabatic-Passage Spin Order Conversion) technique, which can be exploited in NMR experiments with singlet spin states. In this technique magnetization-to-singlet conversion (and singlet-to-magnetization conversion) is performed by using adiabatically ramped RF-fields. Optimization utilizes the GRAPE (Gradient Ascent Pulse Engineering) approach, in which for a fixed search area we assume monotonicity to the envelope of the RF-field. Such an approach allows one to achieve much better performance for APSOC; consequently, the efficiency of magnetization-to-singlet conversion is greatly improved as compared to simple model RF-ramps, e.g., linear ramps. We also demonstrate that the optimization method is reasonably robust to possible inaccuracies in determining NMR parameters of the spin system under study and also in setting the RF-field parameters. The present approach can be exploited in other NMR and EPR applications using adiabatic switching of spin Hamiltonians.
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Affiliation(s)
- Bogdan A Rodin
- 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
| | - Alexandra V Yurkovskaya
- International Tomography Center SB RAS, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia
| | - Konstantin L Ivanov
- International Tomography Center SB RAS, Novosibirsk 630090, Russia; Novosibirsk State University, Novosibirsk 630090, Russia.
| | - Satoru Yamamoto
- Graduate School of Science, Osaka City University, Osaka, Sumiyoshi, Osaka 558-8585, Japan
| | - Kazunobu Sato
- Graduate School of Science, Osaka City University, Osaka, Sumiyoshi, Osaka 558-8585, Japan
| | - Takeji Takui
- Graduate School of Science, Osaka City University, Osaka, Sumiyoshi, Osaka 558-8585, Japan
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Elliott SJ, Meier B, Vuichoud B, Stevanato G, Brown LJ, Alonso-Valdesueiro J, Emsley L, Jannin S, Levitt MH. Hyperpolarized long-lived nuclear spin states in monodeuterated methyl groups. Phys Chem Chem Phys 2018; 20:9755-9759. [PMID: 29595200 PMCID: PMC5933006 DOI: 10.1039/c8cp00253c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 02/15/2018] [Indexed: 01/04/2023]
Abstract
Monodeuterated methyl groups may support a long-lived nuclear spin state, with a relaxation time exceeding the conventional spin-lattice relaxation time T1. Dissolution-DNP (dynamic nuclear polarization) may be used to hyperpolarize such a long-lived spin state. This is demonstrated for the CH2D groups of a piperidine derivative. The polarized sample is manipulated in the ambient magnetic field of the laboratory, without destruction of the hyperpolarized singlet order. Strongly enhanced CH2D signals are observed more than one minute after dissolution, even in the presence of paramagnetic radicals, by which time the NMR signal from the hyperpolarized proton magnetization has completely disappeared.
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Affiliation(s)
- Stuart J. Elliott
- School of Chemistry , University of Southampton , Southampton SO17 1BJ , UK . ;
| | - Benno Meier
- School of Chemistry , University of Southampton , Southampton SO17 1BJ , UK . ;
| | - Basile Vuichoud
- Université de Lyon , CNRS , Université Claude Bernard Lyon 1 , ENS de Lyon , Institut des Sciences Analytiques , UMR 5280 , 69100 Villeurbanne , France
| | - Gabriele Stevanato
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , Batochime , CH-1015 Lausanne , Switzerland
| | - Lynda J. Brown
- School of Chemistry , University of Southampton , Southampton SO17 1BJ , UK . ;
| | | | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , Batochime , CH-1015 Lausanne , Switzerland
| | - Sami Jannin
- Université de Lyon , CNRS , Université Claude Bernard Lyon 1 , ENS de Lyon , Institut des Sciences Analytiques , UMR 5280 , 69100 Villeurbanne , France
| | - Malcolm H. Levitt
- School of Chemistry , University of Southampton , Southampton SO17 1BJ , UK . ;
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32
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Roy S, Appleby KM, Fear EJ, Duckett SB. SABRE-Relay: A Versatile Route to Hyperpolarization. J Phys Chem Lett 2018; 9:1112-1117. [PMID: 29432020 PMCID: PMC5840861 DOI: 10.1021/acs.jpclett.7b03026] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 02/12/2018] [Indexed: 05/22/2023]
Abstract
Signal Amplification by Reversible Exchange (SABRE) is used to switch on the latent singlet spin order of para-hydrogen (p-H2) so that it can hyperpolarize a substrate (sub = nicotinamide, nicotinate, niacin, pyrimidine, and pyrazine). The substrate then reacts reversibly with [Pt(OTf)2(bis-diphenylphosphinopropane)] by displacing OTf- to form [Pt(OTf)(sub)(bis-diphenylphosphinopropane)]OTf. The 31P NMR signals of these metal complexes prove to be enhanced when the substrate possesses an accessible singlet state or long-lived Zeeman polarization. In the case of pyrazine, the corresponding 31P signal was 105 ± 8 times larger than expected, which equated to an 8 h reduction in total scan time for an equivalent signal-to-noise ratio under normal acquisition conditions. Hence, p-H2 derived spin order is successfully relayed into a second metal complex via a suitable polarization carrier (sub). When fully developed, we expect this route involving a second catalyst to successfully hyperpolarize many classes of substrates that are not amenable to the original SABRE method.
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33
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Mamone S, Glöggler S. Nuclear spin singlet states as magnetic on/off probes in self-assembling systems. Phys Chem Chem Phys 2018; 20:22463-22467. [DOI: 10.1039/c8cp04448a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Nuclear singlet states in thermo-responsive peptides are introduced as magnetic on/off switches.
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Affiliation(s)
- Salvatore Mamone
- Max Planck Institute for Biophysical Chemistry
- 37077 Göttingen
- Germany
- Center for Biostructural Imaging of Neurodegeneration of UMG
- 37075 Göttingen
| | - Stefan Glöggler
- Max Planck Institute for Biophysical Chemistry
- 37077 Göttingen
- Germany
- Center for Biostructural Imaging of Neurodegeneration of UMG
- 37075 Göttingen
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34
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Khurana D, Mahesh TS. Bang-bang optimal control of large spin systems: Enhancement of 13C- 13C singlet-order at natural abundance. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 284:8-14. [PMID: 28938135 DOI: 10.1016/j.jmr.2017.09.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 09/06/2017] [Accepted: 09/13/2017] [Indexed: 06/07/2023]
Abstract
Using a bang-bang optimal control technique, we transfer polarization from a set of abundant high-γ nuclei directly to singlet order of a low-γ spin-pair. This approach is analogous to algorithmic cooling (AC) procedure used in quantum state purification. Specifically, we apply this method for enhancing the singlet order in a natural abundant 13C- 13C spin pair by exploiting nine equivalent protons of an 11-spin system. Compared to the standard method not involving polarization transfer, we find an enhancement of singlet order by about 3.4 times. In addition, since the singlet magnetization is contributed by the faster relaxing protons, the recycle delay is halved. Thus effectively we observe a reduction in the overall experimental time by a factor of 23. We also discuss a possible extension of AC, known as heat-bath algorithmic cooling (HBAC).
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Affiliation(s)
- Deepak Khurana
- Department of Physics and NMR Research center, Indian Institute of Science Education and Research, Pune 411008, India.
| | - T S Mahesh
- Department of Physics and NMR Research center, Indian Institute of Science Education and Research, Pune 411008, India; Center for Energy Sciences, Indian Institute of Science Education and Research, Pune 411008, India.
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35
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Ogba OM, Elliott SJ, Kolin DA, Brown LJ, Cevallos S, Sawyer S, Levitt MH, O'Leary DJ. Origins of Small Proton Chemical Shift Differences in Monodeuterated Methyl Groups. J Org Chem 2017; 82:8943-8949. [PMID: 28745884 DOI: 10.1021/acs.joc.7b01356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have recently shown that the small proton chemical shift difference in 2-methyl-1-(methyl-d)piperidine supports a long-lived nuclear spin state. To identify additional candidate molecules with CH2D groups exhibiting accessible long-lived states, and to investigate the factors governing the magnitude of the shift differences, we report a computational and experimental investigation of methyl rotational equilibria and proton chemical shifts in a variety of 2-substituted 1-(methyl-d)piperidines. The polarity and size of the 2-substituent affect the 1,2-stereoisomeric relationship, and consequently, the strength of the rotational asymmetry within the CH2D group. Nonpolar and large 2-substituents prefer the equatorial position, and relatively large shift differences (i.e., > 13 ppb) are observed. Polar and small substituents, however, increasingly prefer the axial position, and medium to small shift differences (i.e., 0 to 9 ppb) are observed. In addition, the diastereotopic CH2D proton chemical shift difference for tricarbonyl(1-chloro-2-deuteriomethylbenzene) chromium(0) was computed, showing that reasonable predictions of these small shift differences can be extended to more complex, organometallic species.
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Affiliation(s)
- O Maduka Ogba
- Department of Chemistry, Pomona College , 645 North College Avenue, Claremont, California 91711, United States
| | - Stuart J Elliott
- School of Chemistry, University of Southampton , Southampton SO17 1BJ, United Kingdom
| | - David A Kolin
- Department of Chemistry, Pomona College , 645 North College Avenue, Claremont, California 91711, United States
| | - Lynda J Brown
- School of Chemistry, University of Southampton , Southampton SO17 1BJ, United Kingdom
| | - Sebastian Cevallos
- Department of Chemistry, Pomona College , 645 North College Avenue, Claremont, California 91711, United States
| | - Stuart Sawyer
- School of Chemistry, University of Southampton , Southampton SO17 1BJ, United Kingdom
| | - Malcolm H Levitt
- School of Chemistry, University of Southampton , Southampton SO17 1BJ, United Kingdom
| | - Daniel J O'Leary
- Department of Chemistry, Pomona College , 645 North College Avenue, Claremont, California 91711, United States
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36
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Roy SS, Norcott P, Rayner PJ, Green GGR, Duckett SB. A Simple Route to Strong Carbon-13 NMR Signals Detectable for Several Minutes. Chemistry 2017; 23:10496-10500. [PMID: 28627764 PMCID: PMC5582603 DOI: 10.1002/chem.201702767] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Indexed: 01/14/2023]
Abstract
Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) suffer from low sensitivity and limited nuclear spin memory lifetimes. Although hyperpolarization techniques increase sensitivity, there is also a desire to increase relaxation times to expand the range of applications addressable by these methods. Here, we demonstrate a route to create hyperpolarized magnetization in 13 C nuclear spin pairs that last much longer than normal lifetimes by storage in a singlet state. By combining molecular design and low-field storage with para-hydrogen derived hyperpolarization, we achieve more than three orders of signal amplification relative to equilibrium Zeeman polarization and an order of magnitude extension in state lifetime. These studies use a range of specifically synthesized pyridazine derivatives and dimethyl p-tolyl phenyl pyridazine is the most successful, achieving a lifetime of about 190 s in low-field, which leads to a 13 C-signal that is visible for 10 minutes.
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Affiliation(s)
- Soumya S. Roy
- Department of ChemistryUniversity of YorkHeslington, YorkYO10 5DDUK
| | - Philip Norcott
- Department of ChemistryUniversity of YorkHeslington, YorkYO10 5DDUK
| | - Peter J. Rayner
- Department of ChemistryUniversity of YorkHeslington, YorkYO10 5DDUK
| | - Gary G. R. Green
- York Neuroimaging CentreThe Biocentre, York Science Park Innovation Way, HeslingtonYorkYO10 5NYUK
| | - Simon B. Duckett
- Department of ChemistryUniversity of YorkHeslington, YorkYO10 5DDUK
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37
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Halse ME, Procacci B, Henshaw SL, Perutz RN, Duckett SB. Coherent evolution of parahydrogen induced polarisation using laser pump, NMR probe spectroscopy: Theoretical framework and experimental observation. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 278:25-38. [PMID: 28347906 DOI: 10.1016/j.jmr.2017.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 06/06/2023]
Abstract
We recently reported a pump-probe method that uses a single laser pulse to introduce parahydrogen (p-H2) into a metal dihydride complex and then follows the time-evolution of the p-H2-derived nuclear spin states by NMR. We present here a theoretical framework to describe the oscillatory behaviour of the resultant hyperpolarised NMR signals using a product operator formalism. We consider the cases where the p-H2-derived protons form part of an AX, AXY, AXYZ or AA'XX' spin system in the product molecule. We use this framework to predict the patterns for 2D pump-probe NMR spectra, where the indirect dimension represents the evolution during the pump-probe delay and the positions of the cross-peaks depend on the difference in chemical shift of the p-H2-derived protons and the difference in their couplings to other nuclei. The evolution of the NMR signals of the p-H2-derived protons, as well as the transfer of hyperpolarisation to other NMR-active nuclei in the product, is described. The theoretical framework is tested experimentally for a set of ruthenium dihydride complexes representing the different spin systems. Theoretical predictions and experimental results agree to within experimental error for all features of the hyperpolarised 1H and 31P pump-probe NMR spectra. Thus we establish the laser pump, NMR probe approach as a robust way to directly observe and quantitatively analyse the coherent evolution of p-H2-derived spin order over micro-to-millisecond timescales.
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Affiliation(s)
- Meghan E Halse
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, York Science Park, University of York, Heslington, York YO10 5NY, UK; Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
| | - Barbara Procacci
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, York Science Park, University of York, Heslington, York YO10 5NY, UK; Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Sarah-Louise Henshaw
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, York Science Park, University of York, Heslington, York YO10 5NY, UK; Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Robin N Perutz
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, York Science Park, University of York, Heslington, York YO10 5NY, UK; Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
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38
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Jhajharia A, Weber EMM, Kempf JG, Abergel D, Bodenhausen G, Kurzbach D. Communication: Dissolution DNP reveals a long-lived deuterium spin state imbalance in methyl groups. J Chem Phys 2017; 146:041101. [PMID: 28147551 DOI: 10.1063/1.4974358] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report the generation and observation of long-lived spin states in deuterated methyl groups by dissolution DNP. These states are based on population imbalances between manifolds of spin states corresponding to irreducible representations of the C3v point group and feature strongly dampened quadrupolar relaxation. Their lifetime depends on the activation energies of methyl group rotation. With dissolution DNP, we can reduce the deuterium relaxation rate by a factor up to 20, thereby extending the experimentally available time window. The intrinsic limitation of NMR spectroscopy of quadrupolar spins by short relaxation times can thus be alleviated.
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Affiliation(s)
- Aditya Jhajharia
- Département de Chimie, Ecole Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), PSL Research University, UPMC University Paris 06, 24 Rue Lhomond, 75005 Paris, France
| | - Emmanuelle M M Weber
- Département de Chimie, Ecole Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), PSL Research University, UPMC University Paris 06, 24 Rue Lhomond, 75005 Paris, France
| | - James G Kempf
- Bruker BioSpin, 15 Fortune Drive, Billerica, Massachusetts 01821, USA
| | - Daniel Abergel
- Département de Chimie, Ecole Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), PSL Research University, UPMC University Paris 06, 24 Rue Lhomond, 75005 Paris, France
| | - Geoffrey Bodenhausen
- Département de Chimie, Ecole Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), PSL Research University, UPMC University Paris 06, 24 Rue Lhomond, 75005 Paris, France
| | - Dennis Kurzbach
- Département de Chimie, Ecole Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), PSL Research University, UPMC University Paris 06, 24 Rue Lhomond, 75005 Paris, France
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39
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Stevanato G, Eills J, Bengs C, Pileio G. A pulse sequence for singlet to heteronuclear magnetization transfer: S2hM. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 277:169-178. [PMID: 28314207 DOI: 10.1016/j.jmr.2017.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 02/28/2017] [Accepted: 03/03/2017] [Indexed: 06/06/2023]
Abstract
We have recently demonstrated, in the context of para-hydrogen induced polarization (PHIP), the conversion of hyperpolarized proton singlet order into heteronuclear magnetisation can be efficiently achieved via a new sequence named S2hM (Singlet to heteronuclear Magnetisation). In this paper we give a detailed theoretical description, supported by an experimental illustration, of S2hM. Theory and experiments on thermally polarized samples demonstrate the proposed method is robust to frequency offset mismatches and radiofrequency field inhomogeneities. The simple implementation, optimisation and the high conversion efficiency, under various regimes of magnetic equivalence, makes S2hM an excellent candidate for a widespread use, particularly within the PHIP arena.
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Affiliation(s)
- Gabriele Stevanato
- Chemistry, University of Southampton, Southampton, United Kingdom; Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - James Eills
- Chemistry, University of Southampton, Southampton, United Kingdom
| | - Christian Bengs
- Chemistry, University of Southampton, Southampton, United Kingdom
| | - Giuseppe Pileio
- Chemistry, University of Southampton, Southampton, United Kingdom.
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40
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Pileio G. Singlet NMR methodology in two-spin-1/2 systems. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 98-99:1-19. [PMID: 28283084 DOI: 10.1016/j.pnmrs.2016.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 11/23/2016] [Accepted: 11/23/2016] [Indexed: 06/06/2023]
Abstract
This paper discusses methodology developed over the past 12years in order to access and manipulate singlet order in systems comprising two coupled spin-1/2 nuclei in liquid-state nuclear magnetic resonance. Pulse sequences that are valid for different regimes are discussed, and fully analytical proofs are given using different spin dynamics techniques that include product operator methods, the single transition operator formalism, and average Hamiltonian theory. Methods used to filter singlet order from byproducts of pulse sequences are also listed and discussed analytically. The theoretical maximum amplitudes of the transformations achieved by these techniques are reported, together with the results of numerical simulations performed using custom-built simulation code.
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Affiliation(s)
- Giuseppe Pileio
- Department of Chemistry, University of Southampton, SO17 1BJ, UK.
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41
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Stevanato G. Alternating Delays Achieve Polarization Transfer (ADAPT) to heteronuclei in PHIP experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 274:148-162. [PMID: 27894879 DOI: 10.1016/j.jmr.2016.10.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 06/06/2023]
Abstract
A new methodology for producing hyperpolarized 13C nuclei in small organic systems via parahydrogen induced polarization (PHIP) is proposed: ADAPT (Alternating Delays Achieve Polarization Transfer). The theoretical foundation of the process is investigated in some detail and experimental examples demonstrating the viability of the approach are provided as well. The number of adjustable parameters is fewer than most of other conversion schemes. The achieved theoretical heteronuclear polarization is close to unity for any examined magnetic equivalence regime. The duration of the pulse sequence, which was successfully implemented, can be shorter than other established methods reducing possible relaxation losses. The conversion scheme is robust to B1 inhomogeneities, but more sensitive to off-resonance RF irradiation.
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Affiliation(s)
- Gabriele Stevanato
- School of Chemistry, University of Southampton, University Road, Southampton, UK; Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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42
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Eills J, Stevanato G, Bengs C, Glöggler S, Elliott SJ, Alonso-Valdesueiro J, Pileio G, Levitt MH. Singlet order conversion and parahydrogen-induced hyperpolarization of 13C nuclei in near-equivalent spin systems. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 274:163-172. [PMID: 27916509 DOI: 10.1016/j.jmr.2016.11.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 11/18/2016] [Accepted: 11/19/2016] [Indexed: 06/06/2023]
Abstract
We have demonstrated two radiofrequency pulse methods which convert the nuclear singlet order of proton spin pairs into the magnetisation of nearby 13C nuclei. These irradiation schemes work well in the near-equivalence regime of the three-spin system, which applies when the difference in the two 1H-13C couplings is much smaller than the 1H-1H coupling. We use pulse sequences to generate thermally polarized singlet states in a reproducible manner, and study the singlet-to-magnetisation transfer step. Preliminary results demonstrate a parahydrogen-enhanced 13C polarization level of at least 9%, providing a signal enhancement factor of more than 9000, using 50% enriched parahydrogen.
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43
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Håkansson P. Prediction of low-field nuclear singlet lifetimes with molecular dynamics and quantum-chemical property surface. Phys Chem Chem Phys 2017; 19:10237-10254. [DOI: 10.1039/c6cp08394c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular dynamics and quantum chemistry methods are implemented to quantify nuclear spin-1/2 pair singlet-state relaxation rates. Illustrated is the relevant spin-internal-motion mechanism (SIM).
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Affiliation(s)
- Pär Håkansson
- School of Chemistry
- University of Southampton
- SO17 1BJ Southampton
- UK
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44
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Glöggler S, Elliott SJ, Stevanato G, Brown RCD, Levitt MH. Versatile magnetic resonance singlet tags compatible with biological conditions. RSC Adv 2017. [DOI: 10.1039/c7ra05196d] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The long lifetime of nuclear singlet states holds promise for the development of molecular tracers to study motional processes in proteins with increased precision or to act as imaging contrast agents.
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Affiliation(s)
- Stefan Glöggler
- School of Chemistry
- University of Southampton
- Southampton SO171BJ
- UK
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45
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Pravdivtsev AN, Kiryutin AS, Yurkovskaya AV, Vieth HM, Ivanov KL. Robust conversion of singlet spin order in coupled spin-1/2 pairs by adiabatically ramped RF-fields. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 273:56-64. [PMID: 27750072 DOI: 10.1016/j.jmr.2016.10.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 10/02/2016] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
We propose a robust and highly efficient NMR technique to create singlet spin order from longitudinal spin magnetization in coupled spin-½ pairs and to perform backward conversion (singlet order)→magnetization. In this method we exploit adiabatic ramping of an RF-field in order to drive transitions between the singlet state and the T± triplet states of a spin pair under study. We demonstrate that the method works perfectly for both strongly and weakly coupled spin pairs, providing a conversion efficiency between the singlet spin order and magnetization, which is equal to the theoretical maximum. We anticipate that the proposed technique is useful for generating long-lived singlet order, for preserving spin hyperpolarization and for analyzing singlet spin order in nearly equivalent spin pairs in specially designed molecules and in low-field NMR studies.
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Affiliation(s)
- Andrey N Pravdivtsev
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Institutskaya 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russia
| | - Alexey S Kiryutin
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Institutskaya 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russia
| | - Alexandra V Yurkovskaya
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Institutskaya 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russia
| | - Hans-Martin Vieth
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Institutskaya 3A, Novosibirsk 630090, Russia; Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, Berlin 14195, Germany
| | - Konstantin L Ivanov
- International Tomography Center, Siberian Branch of the Russian Academy of Science, Institutskaya 3A, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russia.
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46
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Elliott SJ, Brown LJ, Dumez JN, Levitt MH. Long-lived nuclear spin states in rapidly rotating CH 2D groups. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 272:87-90. [PMID: 27665566 DOI: 10.1016/j.jmr.2016.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023]
Abstract
Although monodeuterated methyl groups support proton long-lived states, hindering of the methyl rotation limits the singlet relaxation time. We demonstrate an experimental case in which the rapid rotation of the CH2D group extends the singlet lifetime but does not quench the chemical shift difference between the CH2D protons, induced by the chiral environment. Proton singlet order is accessed using Spin-Lock Induced Crossing (SLIC) experiments, showing that the singlet relaxation time TS is over 2min, exceeding the longitudinal relaxation time T1 by a factor of more than 10. This result shows that proton singlet states may be accessible and long-lived in rapidly rotating CH2D groups.
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Affiliation(s)
- Stuart J Elliott
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Lynda J Brown
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Jean-Nicolas Dumez
- Institut de Chimie des Substances Naturelles, CNRS UPR2301, Univ. Paris-Sud, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Malcolm H Levitt
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom.
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47
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Hyperpolarization MRI: Preclinical Models and Potential Applications in Neuroradiology. Top Magn Reson Imaging 2016; 25:31-7. [PMID: 26848559 DOI: 10.1097/rmr.0000000000000076] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hyperpolarization is a novel technology that can dramatically increase signal to noise in magnetic resonance. The method is being applied to small injectable endogenous molecules, which can be used to monitor transient in vivo metabolic events, in real time. The emergence of hyperpolarized C-labeled probes, specifically C pyruvate, has enabled monitoring of core cellular metabolic events. Neuro-oncological applications have been demonstrated in preclinical models. Many more applications of this technology are envisioned, with transformative potential in magnetic resonance imaging.
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Roy SS, Rayner PJ, Norcott P, Green GGR, Duckett SB. Long-lived states to sustain SABRE hyperpolarised magnetisation. Phys Chem Chem Phys 2016; 18:24905-24911. [PMID: 27711398 PMCID: PMC5436088 DOI: 10.1039/c6cp02844f] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 08/15/2016] [Indexed: 11/22/2022]
Abstract
The applicability of the magnetic resonance (MR) technique in the liquid phase is limited by poor sensitivity and short nuclear spin coherence times which are insufficient for many potential applications. Here we illustrate how it is possible to address both of these issues simultaneously by harnessing long-lived hyperpolarised spin states that are formed by adapting the Signal Amplification by Reversible Exchange (SABRE) technique. We achieve more than 4% net 1H-polarisation in a long-lived form that remains detectable for over ninety seconds by reference to proton pairs in the biologically important molecule nicotinamide and a pyrazine derivative whose in vivo imaging will offer a new route to probe disease in the future.
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Affiliation(s)
- Soumya S Roy
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
| | - Peter J Rayner
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
| | - Philip Norcott
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
| | - Gary G R Green
- York Neuroimaging Centre, The Biocentre, York Science Park, Innovation Way, Heslington, York, YO10 5DD, UK
| | - Simon B Duckett
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
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49
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Turanov A, Khitrin A. Measurement of J-couplings between chemically equivalent nuclei using off-resonance decoupling. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 270:31-34. [PMID: 27389640 DOI: 10.1016/j.jmr.2016.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 06/20/2016] [Accepted: 06/28/2016] [Indexed: 06/06/2023]
Abstract
The method of measuring J-couplings between chemically equivalent nuclei in isotopically/magnetically non-equivalent environment, based on off-resonance decoupling, is described. The approach uses intensities, rather than frequencies of the spectral peaks and, therefore, the accuracy of measurement is not limited by spectral resolution.
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Affiliation(s)
- Alexander Turanov
- Department of Chemistry, Kent State University, OH 44242, USA; Zavoisky Physical-Technical Institute RAS, Kazan 420029, Russia
| | - Anatoly Khitrin
- Department of Chemistry, Kent State University, OH 44242, USA.
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50
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Zhang Y, Duan X, Soon PC, Sychrovský V, Canary JW, Jerschow A. Limits in Proton Nuclear Singlet-State Lifetimes Measured with para-Hydrogen-Induced Polarization. Chemphyschem 2016; 17:2967-2971. [PMID: 27460052 DOI: 10.1002/cphc.201600663] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Indexed: 01/10/2023]
Abstract
The synthesis of a hyperpolarized molecule was developed, where the polarization and the singlet state were preserved over two controlled chemical steps. Nuclear singlet-state lifetimes close to 6 min for protons are reported in dimethyl fumarate. Owing to the high symmetry (AA'X3 X3 ' and A2 systems), the singlet-state readout requires either a chemical desymmetrization or a long and repeated spin lock. Using DFT calculations and relaxation models, we further determine nuclear spin singlet lifetime limiting factors, which include the intramolecular dipolar coupling mechanism (proton-proton and proton-deuterium), the chemical shift anisotropy mechanism (symmetric and antisymmetric), and the intermolecular dipolar coupling mechanism (to oxygen and deuterium). If the limit of paramagnetic relaxation caused by residual oxygen could be lifted, the intramolecular dipolar coupling to deuterium would become the limiting relaxation mechanism and proton lifetimes upwards of 26 min could become available in the molecules considered here (dimethyl maleate and dimethyl fumarate).
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Affiliation(s)
- Yuning Zhang
- Department of Chemistry, New York University, 100 Washington Sq. East, New York, NY, 10003, USA
| | - Xueyou Duan
- Department of Chemistry, New York University, 100 Washington Sq. East, New York, NY, 10003, USA
| | - Pei Che Soon
- Department of Chemistry, New York University, 100 Washington Sq. East, New York, NY, 10003, USA
| | - Vladimír Sychrovský
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo náměstí 2, 166 10, Praha 6, Czech Republic.,Department of Electrotechnology, Electrical Engineering, Czech Technical University, Technická 2, 166 27, Prague 6, Czech Republic
| | - James W Canary
- Department of Chemistry, New York University, 100 Washington Sq. East, New York, NY, 10003, USA.
| | - Alexej Jerschow
- Department of Chemistry, New York University, 100 Washington Sq. East, New York, NY, 10003, USA.
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