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Wang H, Cleary MB, Lewis LC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Enzyme Control Over Ferric Iron Magnetostructural Properties. Angew Chem Int Ed Engl 2022; 61:e202114019. [PMID: 34814231 PMCID: PMC8935392 DOI: 10.1002/anie.202114019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Indexed: 01/19/2023]
Abstract
Fe3+ complexes in aqueous solution can exist as discrete mononuclear species or multinuclear magnetically coupled species. Stimuli-driven change to Fe3+ speciation represents a powerful mechanistic basis for magnetic resonance sensor technology, but ligand design strategies to exert precision control of aqueous Fe3+ magnetostructural properties are entirely underexplored. In pursuit of this objective, we rationally designed a ligand to strongly favor a dinuclear μ-oxo-bridged and antiferromagnetically coupled complex, but which undergoes carboxylesterase mediated transformation to a mononuclear high-spin Fe3+ chelate resulting in substantial T1 -relaxivity increase. The data communicated demonstrate proof of concept for a novel and effective strategy to exert biochemical control over aqueous Fe3+ magnetic, structural, and relaxometric properties.
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Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Michael B. Cleary
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Luke C. Lewis
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, 43210, United States
| | - Jeffrey W. Bacon
- Department of Chemistry, Boston University, Boston, Massachusetts, 02215, United States
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States,Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Hannah S. Shafaat
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, 43210, United States
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States,Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital/ Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
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Wang H, Cleary MB, Lewis LC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Enzyme Control Over Ferric Iron Magnetostructural Properties. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Michael B. Cleary
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Luke C. Lewis
- Department of Chemistry and Biochemistry The Ohio State University Columbus OH 43210 USA
| | | | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
| | - Hannah S. Shafaat
- Department of Chemistry and Biochemistry The Ohio State University Columbus OH 43210 USA
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging
- Institute for Innovation in Imaging Department of Radiology Massachusetts General Hospital/Harvard Medical School 149 Thirteenth Street Charlestown MA 02129 USA
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Wang H, Wong A, Lewis LC, Nemeth GR, Jordan VC, Bacon JW, Caravan P, Shafaat HS, Gale EM. Rational Ligand Design Enables pH Control over Aqueous Iron Magnetostructural Dynamics and Relaxometric Properties. Inorg Chem 2020; 59:17712-17721. [PMID: 33216537 DOI: 10.1021/acs.inorgchem.0c02923] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Complexes of Fe3+ engage in rich aqueous solution speciation chemistry in which discrete molecules can react with solvent water to form multinuclear μ-oxo and μ-hydroxide bridged species. Here we demonstrate how pH- and concentration-dependent equilibration between monomeric and μ-oxo-bridged dimeric Fe3+ complexes can be controlled through judicious ligand design. We purposed this chemistry to develop a first-in-class Fe3+-based MR imaging probe, Fe-PyCy2AI, that undergoes relaxivity change via pH-mediated control of monomer vs dimer speciation. The monomeric complex exists in a S = 5/2 configuration capable of inducing efficient T1-relaxation, whereas the antiferromagnetically coupled dimeric complex is a much weaker relaxation agent. The mechanisms underpinning the pH dependence on relaxivity were interrogated by using a combination of pH potentiometry, 1H and 17O relaxometry, electronic absorption spectroscopy, bulk magnetic susceptibility, electron paramagnetic resonance spectroscopy, and X-ray crystallography measurements. Taken together, the data demonstrate that PyCy2AI forms a ternary complex with high-spin Fe3+ and a rapidly exchanging water coligand, [Fe(PyCy2AI)(H2O)]+ (ML), which can deprotonate to form the high-spin complex [Fe(PyCy2AI)(OH)] (ML(OH)). Under titration conditions of 7 mM Fe complex, water coligand deprotonation occurs with an apparent pKa 6.46. Complex ML(OH) dimerizes to form the antiferromagnetically coupled dimeric complex [(Fe(PyCy2AI))2O] ((ML)2O) with an association constant (Ka) of 5.3 ± 2.2 mM-1. The relaxivity of the monomeric complexes are between 7- and 18-fold greater than the antiferromagnetically coupled dimer at applied field strengths ranging between 1.4 and 11.7 T. ML(OH) and (ML)2O interconvert rapidly within the pH 6.0-7.4 range that is relevant to human pathophysiology, resulting in substantial observed relaxivity change. Controlling Fe3+ μ-oxo bridging interactions through rational ligand design and in response to local chemical environment offers a robust mechanism for biochemically responsive MR signal modulation.
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Affiliation(s)
| | | | - Luke C Lewis
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | | | | | - Jeffrey W Bacon
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | | | - Hannah S Shafaat
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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Kuźnik N, Wyskocka M, Jarosz M, Oczek L, Goraus S, Komor R, Krawczyk T, Kempka M. Amino-phenol complexes of Fe(III) as promising T1 accelerators. ARAB J CHEM 2019. [DOI: 10.1016/j.arabjc.2014.11.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Benders S, Strassl F, Fenger B, Blümich B, Herres-Pawlis S, Küppers M. Imaging of copper oxygenation reactions in a bubble flow. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:826-830. [PMID: 29682795 DOI: 10.1002/mrc.4742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/04/2018] [Indexed: 06/08/2023]
Abstract
Reactions of gases with liquids play a crucial role in the production of many bulk chemicals. Often, the gas is bubbled into the chosen reactor. Most of the processes at the gas-liquid interface of the bubbles and in their tails are not fully understood and warrant further investigation. For this purpose, NMR imaging or Magnetic Resonance Imaging has been applied to visualize some of the processes in the bubble tail. To generate sufficient contrast, a magnetogenic gas-liquid reaction associated with a change of magnetic state, from diamagnetic to paramagnetic, was employed. In this work, a copper(I)-based compound was oxidized to copper(II) to exploit relaxation contrast. To match the speed of the rising bubbles to the acquisition time of the spin-echo imaging sequence, polyethylene glycol was added to increase the viscosity of the reacting solution. Images of the oxygen ingress into a static solution as well as of oxygen bubbles rising in the solution are presented. In both cases, changes in magnetism were observed, which reported the hydrodynamic processes.
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Affiliation(s)
- Stefan Benders
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Aachen, 52074, Germany
| | - Florian Strassl
- Institut für Anorganische Chemie, RWTH Aachen University, Aachen, 52074, Germany
| | - Bastian Fenger
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Aachen, 52074, Germany
| | - Bernhard Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Aachen, 52074, Germany
| | - Sonja Herres-Pawlis
- Institut für Anorganische Chemie, RWTH Aachen University, Aachen, 52074, Germany
| | - Markus Küppers
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Aachen, 52074, Germany
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Thorarinsdottir AE, Gaudette AI, Harris TD. Spin-crossover and high-spin iron(ii) complexes as chemical shift 19F magnetic resonance thermometers. Chem Sci 2017; 8:2448-2456. [PMID: 28694955 PMCID: PMC5477811 DOI: 10.1039/c6sc04287b] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 12/20/2016] [Indexed: 12/22/2022] Open
Abstract
The potential utility of paramagnetic transition metal complexes as chemical shift 19F magnetic resonance (MR) thermometers is demonstrated. Further, spin-crossover FeII complexes are shown to provide much higher temperature sensitivity than do the high-spin analogues, owing to the variation of spin state with temperature in the former complexes. This approach is illustrated through a series of FeII complexes supported by symmetrically and asymmetrically substituted 1,4,7-triazacyclononane ligand scaffolds bearing 3-fluoro-2-picolyl derivatives as pendent groups (L x ). Variable-temperature magnetic susceptibility measurements, in conjunction with UV-vis and NMR data, show thermally-induced spin-crossover for [Fe(L1)]2+ in H2O, with T1/2 = 52(1) °C. Conversely, [Fe(L2)]2+ remains high-spin in the temperature range 4-61 °C. Variable-temperature 19F NMR spectra reveal the chemical shifts of the complexes to exhibit a linear temperature dependence, with the two peaks of the spin-crossover complex providing temperature sensitivities of +0.52(1) and +0.45(1) ppm per °C in H2O. These values represent more than two-fold higher sensitivity than that afforded by the high-spin analogue, and ca. 40-fold higher sensitivity than diamagnetic perfluorocarbon-based thermometers. Finally, these complexes exhibit excellent stability in a physiological environment, as evidenced by 19F NMR spectra collected in fetal bovine serum.
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Affiliation(s)
- Agnes E Thorarinsdottir
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , IL 60208-3113 , USA .
| | - Alexandra I Gaudette
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , IL 60208-3113 , USA .
| | - T David Harris
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , IL 60208-3113 , USA .
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Gaudette AI, Thorarinsdottir AE, Harris TD. pH-Dependent spin state population and 19F NMR chemical shift via remote ligand protonation in an iron(ii) complex. Chem Commun (Camb) 2017; 53:12962-12965. [DOI: 10.1039/c7cc08158h] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
An FeII complex that features a pH-dependent spin state population and 19F chemical shift, by virtue of a variable ligand protonation state, is described.
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Baroni S, Colombo Serra S, Fringuello Mingo A, Lux G, Giovenzana GB, Lattuada L. Synthesis and Relaxometric Characterization of a New Mn(II)-EDTA-Deoxycholic Acid Conjugate Complex as a Potential MRI Blood Pool Agent. ChemistrySelect 2016. [DOI: 10.1002/slct.201600349] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- S. Baroni
- Molecular Imaging Center; Department of Molecular Biotechnologies & Health Sciences; Università di Torino; Via Nizza 52 10100 Torino (TO) Italy
| | - Sonia Colombo Serra
- Bracco Imaging SpA; Bracco Research Center; Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
| | - Alberto Fringuello Mingo
- Bracco Imaging SpA; Bracco Research Center; Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
- Dipartimento di Fisica; Università di Torino; Via Pietro Giuria 1 10100 Torino (TO) Italy
| | - G. Lux
- Bracco Imaging SpA; Bracco Research Center; Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
| | - G. B. Giovenzana
- Dipartimento di Scienze del Farmaco; Università degli Studi del Piemonte Orientale “A. Avogadro”; Largo Donegani 2/3 28100 Novara (NO) Italy
| | - L. Lattuada
- Bracco Imaging SpA; Bracco Research Center; Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
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Heitmann G, Schütt C, Gröbner J, Huber L, Herges R. Azoimidazole functionalized Ni-porphyrins for molecular spin switching and light responsive MRI contrast agents. Dalton Trans 2016; 45:11407-12. [DOI: 10.1039/c6dt01727d] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Molecular spin switching with light under aqueous conditions has been performed with azoimidazole functionalized Ni-porphyrins. The change in contrast in MRI images is clearly visible.
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Affiliation(s)
- Gernot Heitmann
- Otto Diels-Institut für Organische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel
- Germany
| | - Christian Schütt
- Otto Diels-Institut für Organische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel
- Germany
| | - Jens Gröbner
- Otto Diels-Institut für Organische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel
- Germany
| | - Lukas Huber
- Molecular Imaging North Competence Center
- Christian-Albrechts-Universität zu Kiel
- 24118 Kiel
- Germany
| | - Rainer Herges
- Otto Diels-Institut für Organische Chemie
- Christian-Albrechts-Universität zu Kiel
- D-24098 Kiel
- Germany
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Kuźnik N, Chmielniak U. Studies on the redox activity of iron N,O-complexes: Potential T 1-contrast agents. Redox Rep 2016; 21:37-44. [PMID: 26023764 PMCID: PMC6837439 DOI: 10.1179/1351000215y.0000000017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
OBJECTIVES The goal of this study was to determine the redox activity of iron (ethylenebis[2-(o-hydroxyphenyl)glycine]) (EHPG) and (ethylenebis[2-(o-hydroxybenzyl)glycine]) (EHBG) (N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid) derivative complexes and of some N,O-salan complexes of iron. The hexadentate chelate (EHPG and EHBG) ligands varied in their substituents (polar OMe, NHAc, or lipophilic Ph), while the latter had different charge and lipophilicity. The low redox activity of these complexes is important in their potential applications as magnetic resonance imaging contrast agents. METHODS Redox activity was assessed in the entire Haber-Weiss cycle and separately in the Fenton reaction. The spin-trapping method with 5,5-dimethyl-1-pyrroline-N-oxide monitored in electron paramagnetic resonance was used. The standard Mn marker was applied as a reference for quantitative analysis. Additionally, ascorbate oxidation was analyzed with UV-Vis spectrophotometry. RESULTS Both the Haber-Weiss cycle and in particular the Fenton reaction showed low redox activity of the studied complexes, which did not exceed 30% of [Fe(EDTA)]- or FeCl3 activity. The N,O-salan complexes expressed even lower activity, i.e. 10-20% activity of [Fe(EDTA)]-. DISCUSSION For the EHPG and EHBG complexes, it is likely that hydrophobicity and the possibility of H-bond formation play a major role in the resulting redox effects. For this reason, chelates equipped with phenyl groups in the majority belong to less redox-active complexes. For N,O-salan complexes, activity is not correlated with the charge of the coordination sphere, but again, the highly hydrophobic character of the groups and the non-pendant substituents capable of H-bonding that are present in these ligands limit the affinity of hydrophilic species.
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Affiliation(s)
- Nikodem Kuźnik
- Faculty of Chemistry, Silesian University of
Technology, M. Strzody 9, 44-100 Gliwice,
Poland
| | - Urszula Chmielniak
- Faculty of Chemistry, Silesian University of
Technology, M. Strzody 9, 44-100 Gliwice,
Poland
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11
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Barrett SA, Halcrow MA. Anion-dependent spin crossover in solution for an iron(ii) complex of a 1H-pyrazolyl ligand. RSC Adv 2014. [DOI: 10.1039/c4ra00230j] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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12
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Hasserodt J, Kolanowski JL, Touti F. Magnetogenese in Wasser, ausgelöst durch einen chemischen Analyten. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201305662] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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13
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Hasserodt J, Kolanowski JL, Touti F. Magnetogenesis in Water Induced by a Chemical Analyte. Angew Chem Int Ed Engl 2013; 53:60-73. [DOI: 10.1002/anie.201305662] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Indexed: 11/12/2022]
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Iron(II) complexes of 2,6-di(1-alkylpyrazol-3-yl)pyridine derivatives – The influence of distal substituents on the spin state of the iron centre. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.01.057] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Kolanowski JL, Jeanneau E, Steinhoff R, Hasserodt J. Bispidine Platform Grants Full Control over Magnetic State of Ferrous Chelates in Water. Chemistry 2013; 19:8839-49. [DOI: 10.1002/chem.201300604] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Indexed: 11/11/2022]
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Touti F, Maurin P, Hasserodt J. Magnetogenese unter physiologischen Bedingungen mit molekularen Sonden, die auf (bio-)chemische Analyten ansprechen. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201208848] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Touti F, Maurin P, Hasserodt J. Magnetogenesis under physiological conditions with probes that report on (bio-)chemical stimuli. Angew Chem Int Ed Engl 2013; 52:4654-8. [PMID: 23526602 DOI: 10.1002/anie.201208848] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 01/23/2013] [Indexed: 11/10/2022]
Abstract
Switched on: A molecular concept allows the generation of magnetism in an aqueous sample under the influence of a freshly added (bio-)chemical analyte. The analyte (a chemical reagent or enzyme) triggers the conversion of the probe, a diamagnetic chelate compound, into a paramagnetic compound (see scheme). The two probes prepared are easily accessible iron(II) chelates, and are operative at physiological conditions and/or in serum.
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Affiliation(s)
- Faycal Touti
- Laboratoire de Chimie, UMR CNRS UCBL 5182, Université de Lyon-ENS de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
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Promising strategies for Gd-based responsive magnetic resonance imaging contrast agents. Curr Opin Chem Biol 2012; 17:158-66. [PMID: 23141598 DOI: 10.1016/j.cbpa.2012.10.031] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 10/18/2012] [Accepted: 10/20/2012] [Indexed: 11/22/2022]
Abstract
Magnetic resonance imaging is a powerful imaging modality that is often coupled with paramagnetic contrast agents based on gadolinium to enhance sensitivity and image quality. Responsive contrast agents are key to furthering the diagnostic potential of MRI, both to provide anatomical information and to discern biochemical activity. Recent design of responsive gadolinium-based T₁ agents has made interesting progress, with the development of novel complexes which sense their chemical environment through changes in the coordination of water molecules, the molecular tumbling time or the number of metal centres. Particular promising design strategies include the use of multimeric systems, and the development of dual imaging probes.
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