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De Kreijger S, Cauët E, Elias B, Troian-Gautier L. Synthesis of Ru(II) and Os(II) photosensitizers bearing one 9,10-diamino-1,4,5,8-tetraazaphenanthrene scaffold. Dalton Trans 2024; 53:10270-10284. [PMID: 38829264 DOI: 10.1039/d4dt01077a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
The synthesis of eight Ru(II) and Os(II) photosensitizers bearing a common 9,10-disubstituted-1,4,5,8-tetraazaphenanthrene backbone is reported. With Os(II) photosensitizers, the 9,10-diNH2-1,4,5,8-tetraazaphenanthrene could be directly chelated onto the metal center via the heteroaromatic moiety, whereas similar conditions using Ru(II) resulted in the formation of an o-quinonediimine derivative. Hence, an alternative route, proceeding via the chelation of 9-NH2-10-NO2-1,4,5,8-tetraazaphenanthrene and subsequent ligand reduction of the corresponding photosensitizers was developed. Photosensitizers chelated via the polypyridyl-type moiety exhibited classical photophysical properties whereas the o-quinonediimine chelated Ru(II) analogues exhibited red-shifted absorption (520 nm) and no photoluminescence at room temperature in acetonitrile. The most promising photosensitizers were investigated for excited-state quenching with guanosine-5'-monophosphate in aqueous buffered conditions where reductive excited-state electron transfer was observed by nanosecond transient absorption spectroscopy.
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Affiliation(s)
- Simon De Kreijger
- UCLouvain, Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1/L4.01.02, B-1348 Louvain-la-Neuve, Belgium.
| | - Emilie Cauët
- Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (CP 160/09), Université libre de Bruxelles (ULB), 50 av. F. D. Roosevelt, CP160/09, B-1050 Brussels, Belgium
| | - Benjamin Elias
- UCLouvain, Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1/L4.01.02, B-1348 Louvain-la-Neuve, Belgium.
| | - Ludovic Troian-Gautier
- UCLouvain, Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1/L4.01.02, B-1348 Louvain-la-Neuve, Belgium.
- Wel Research Institute, Avenue Pasteur 6, 1300 Wavre, Belgium
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2
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Goodwin MJ, Dickenson JC, Ripak A, Deetz AM, McCarthy JS, Meyer GJ, Troian-Gautier L. Factors that Impact Photochemical Cage Escape Yields. Chem Rev 2024; 124:7379-7464. [PMID: 38743869 DOI: 10.1021/acs.chemrev.3c00930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The utilization of visible light to mediate chemical reactions in fluid solutions has applications that range from solar fuel production to medicine and organic synthesis. These reactions are typically initiated by electron transfer between a photoexcited dye molecule (a photosensitizer) and a redox-active quencher to yield radical pairs that are intimately associated within a solvent cage. Many of these radicals undergo rapid thermodynamically favored "geminate" recombination and do not diffuse out of the solvent cage that surrounds them. Those that do escape the cage are useful reagents that may undergo subsequent reactions important to the above-mentioned applications. The cage escape process and the factors that determine the yields remain poorly understood despite decades of research motivated by their practical and fundamental importance. Herein, state-of-the-art research on light-induced electron transfer and cage escape that has appeared since the seminal 1972 review by J. P. Lorand entitled "The Cage Effect" is reviewed. This review also provides some background for those new to the field and discusses the cage escape process of both homolytic bond photodissociation and bimolecular light induced electron transfer reactions. The review concludes with some key goals and directions for future research that promise to elevate this very vibrant field to even greater heights.
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Affiliation(s)
- Matthew J Goodwin
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - John C Dickenson
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Alexia Ripak
- Université catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium
| | - Alexander M Deetz
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jackson S McCarthy
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Gerald J Meyer
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Ludovic Troian-Gautier
- Université catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium
- Wel Research Institute, Avenue Pasteur 6, 1300 Wavre, Belgium
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3
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Aydogan A, Bangle RE, Cadranel A, Turlington MD, Conroy DT, Cauët E, Singleton ML, Meyer GJ, Sampaio RN, Elias B, Troian-Gautier L. Accessing Photoredox Transformations with an Iron(III) Photosensitizer and Green Light. J Am Chem Soc 2021; 143:15661-15673. [PMID: 34529421 DOI: 10.1021/jacs.1c06081] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Efficient excited-state electron transfer between an iron(III) photosensitizer and organic electron donors was realized with green light irradiation. This advance was enabled by the use of the previously reported iron photosensitizer, [Fe(phtmeimb)2]+ (phtmeimb = {phenyl[tris(3-methyl-imidazolin-2-ylidene)]borate}, that exhibited long-lived and luminescent ligand-to-metal charge-transfer (LMCT) excited states. A benchmark dehalogenation reaction was investigated with yields that exceed 90% and an enhanced stability relative to the prototypical photosensitizer [Ru(bpy)3]2+. The initial catalytic step is electron transfer from an amine to the photoexcited iron sensitizer, which is shown to occur with a large cage-escape yield. For LMCT excited states, this reductive electron transfer is vectorial and may be a general advantage of Fe(III) photosensitizers. In-depth time-resolved spectroscopic methods, including transient absorption characterization from the ultraviolet to the infrared regions, provided a quantitative description of the catalytic mechanism with associated rate constants and yields.
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Affiliation(s)
- Akin Aydogan
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium
| | - Rachel E Bangle
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alejandro Cadranel
- Department of Chemistry and Pharmacy, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany.,Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Pabellón 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina.,CONICET - Universidad de Buenos Aires. Instituto de Química Física de Materiales, Medio Ambiente y Energía (INQUIMAE), Pabellón 2, Ciudad Universitaria, C1428EHA Buenos Aires, Argentina
| | - Michael D Turlington
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Daniel T Conroy
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Emilie Cauët
- Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (CP 160/09), Université Libre de Bruxelles, 50 av. F. D. Roosevelt, B-1050 Brussels, Belgium
| | - Michael L Singleton
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium
| | - Gerald J Meyer
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Renato N Sampaio
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973-5000, United States
| | - Benjamin Elias
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium
| | - Ludovic Troian-Gautier
- Université Catholique de Louvain (UCLouvain), Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Place Louis Pasteur 1, bte L4.01.02, 1348 Louvain-la-Neuve, Belgium.,Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States.,Laboratoire de Chimie Organique, Université Libre de Bruxelles (ULB), CP 160/06, 50 avenue F.D. Roosevelt, 1050 Brussels, Belgium
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4
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Keane PM, Tory J, Towrie M, Sazanovich IV, Cardin CJ, Quinn SJ, Hartl F, Kelly JM, Long C. Spectro-electrochemical Studies on [Ru(TAP) 2(dppz)] 2+-Insights into the Mechanism of its Photosensitized Oxidation of Oligonucleotides. Inorg Chem 2018; 58:663-671. [PMID: 30540448 DOI: 10.1021/acs.inorgchem.8b02859] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[Ru(TAP)2(dppz)]2+ (TAP = 1,4,5,8-tetraazaphenanthrene; dppz = dipyrido[3,2- a:2',3'- c]phenazine) is known to photo-oxidize guanine in DNA. Whether this oxidation proceeds by direct photoelectron transfer or by proton-coupled electron transfer is still unknown. To help distinguish between these mechanisms, spectro-electrochemical experiments have been carried out with [Ru(TAP)2(dppz)]2+ in acetonitrile. The UV-vis and mid-IR spectra obtained for the one-electron reduced product were compared to those obtained by picosecond transient absorption and time-resolved infrared experiments of [Ru(TAP)2(dppz)]2+ bound to guanine-containing DNA. An interesting feature of the singly reduced species is an electronic transition in the near-IR region (with λmax at 1970 and 2820 nm). Density functional and time-dependent density functional theory simulations of the vibrational and electronic spectra of [Ru(TAP)2(dppz)]2+, the reduced complex [Ru(TAP)2(dppz)]+, and four isomers of [Ru(TAP)(TAPH)(dppz)]2+ (a possible product of proton-coupled electron transfer) were performed. Significantly, these predict absorption bands at λ > 1900 nm (attributed to a ligand-to-metal charge-transfer transition) for [Ru(TAP)2(dppz)]+ but not for [Ru(TAP)(TAPH)(dppz)]2+. Both the UV-vis and mid-IR difference absorption spectra of the electrochemically generated singly reduced species [Ru(TAP)2(dppz)]+ agree well with the transient absorption and time-resolved infrared spectra previously determined for the transient species formed by photoexcitation of [Ru(TAP)2(dppz)]2+ intercalated in guanine-containing DNA. This suggests that the photochemical process in DNA proceeds by photoelectron transfer and not by a proton-coupled electron transfer process involving formation of [Ru(TAP)(TAPH)(dppz)]2+, as is proposed for the reaction with 5'-guanosine monophosphate. Additional infrared spectro-electrochemical measurements and density functional calculations have also been carried out on the free TAP ligand. These show that the TAP radical anion in acetonitrile also exhibits strong broad near-IR electronic absorption (λmax at 1750 and 2360 nm).
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Affiliation(s)
- Páraic M Keane
- School of Chemistry , University of Dublin, Trinity College , Dublin 2 , Ireland.,Department of Chemistry , University of Reading , Whiteknights, Reading RG6 6AD , United Kingdom
| | - Joanne Tory
- Department of Chemistry , University of Reading , Whiteknights, Reading RG6 6AD , United Kingdom
| | - Michael Towrie
- Science and Technology Facilities Council , Rutherford Appleton Laboratory, Research Complex at Harwell , Didcot, Oxfordshire OX11 0QX , United Kingdom
| | - Igor V Sazanovich
- Science and Technology Facilities Council , Rutherford Appleton Laboratory, Research Complex at Harwell , Didcot, Oxfordshire OX11 0QX , United Kingdom
| | - Christine J Cardin
- Department of Chemistry , University of Reading , Whiteknights, Reading RG6 6AD , United Kingdom
| | - Susan J Quinn
- School of Chemistry , University College Dublin , Belfield, Dublin 4 , Ireland
| | - František Hartl
- Department of Chemistry , University of Reading , Whiteknights, Reading RG6 6AD , United Kingdom
| | - John M Kelly
- School of Chemistry , University of Dublin, Trinity College , Dublin 2 , Ireland
| | - Conor Long
- School of Chemical Sciences , Dublin City University , Dublin 9 , Ireland
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5
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Brady MD, Troian-Gautier L, Sampaio RN, Motley TC, Meyer GJ. Optimization of Photocatalyst Excited- and Ground-State Reduction Potentials for Dye-Sensitized HBr Splitting. ACS APPLIED MATERIALS & INTERFACES 2018; 10:31312-31323. [PMID: 30130392 DOI: 10.1021/acsami.8b09134] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Dye-sensitized bromide oxidation was investigated using a series of four ruthenium polypyridyl photocatalysts anchored to SnO2/TiO2 core/shell mesoporous thin films through 2,2'-bipyridine-4,4'-diphosphonic acid anchoring groups. The ground- and excited-state reduction potentials were tuned over 500 mV by the introduction of electron withdrawing groups in the 4 and 4' positions of the ancillary bipyridine ligands. Upon light excitation of the surface-bound photocatalysts, excited-state electron injection yielded an oxidized photocatalyst that was regenerated through bromide oxidation. High injection quantum yields (Φinj) and regeneration quantum yields (Φreg) were essential to obtain efficient bromide oxidation yet required a photocatalyst that is both a potent photoreductant and a strong oxidant after excited-state injection. The four photocatalysts utilized in this manuscript ranged from unity Φinj (1.0) and minimal Φreg (0.037) to minimal Φinj (0.09) and unity Φreg (1.0). The photocatalyst that displayed the highest overall dye-sensitized photoelectrosynthesis cell performances exhibited near unity Φreg (0.99), while a significant Φinj was still preserved (0.59). Thus, these results highlighted the delicate interplay between the ground- and excited-state reduction potentials of photocatalysts for dye-sensitized hydrobromic acid splitting.
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Affiliation(s)
- Matthew D Brady
- Department of Chemistry , University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States
| | - Ludovic Troian-Gautier
- Department of Chemistry , University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States
| | - Renato N Sampaio
- Department of Chemistry , University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States
| | - Tyler C Motley
- Department of Chemistry , University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States
| | - Gerald J Meyer
- Department of Chemistry , University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States
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Kajouj S, Marcelis L, Mattiuzzi A, Grassin A, Dufour D, Van Antwerpen P, Boturyn D, Defrancq E, Surin M, De Winter J, Gerbaux P, Jabin I, Moucheron C. Synthesis and photophysical studies of a multivalent photoreactive Ru II-calix[4]arene complex bearing RGD-containing cyclopentapeptides. Beilstein J Org Chem 2018; 14:1758-1768. [PMID: 30112081 PMCID: PMC6071717 DOI: 10.3762/bjoc.14.150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 06/21/2018] [Indexed: 01/09/2023] Open
Abstract
Photoactive ruthenium-based complexes are actively studied for their biological applications as potential theragnostic agents against cancer. One major issue of these inorganic complexes is to penetrate inside cells in order to fulfil their function, either sensing the internal cell environment or exert a photocytotoxic activity. The use of lipophilic ligands allows the corresponding ruthenium complexes to passively diffuse inside cells but limits their structural and photophysical properties. Moreover, this strategy does not provide any cell selectivity. This limitation is also faced by complexes anchored on cell-penetrating peptides. In order to provide a selective cell targeting, we developed a multivalent system composed of a photoreactive ruthenium(II) complex tethered to a calix[4]arene platform bearing multiple RGD-containing cyclopentapeptides. Extensive photophysical and photochemical characterizations of this Ru(II)–calixarene conjugate as well as the study of its photoreactivity in the presence of guanosine monophosphate have been achieved. The results show that the ruthenium complex should be able to perform efficiently its photoinduced cytotoxic activity, once incorporated into targeted cancer cells thanks to the multivalent platform.
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Affiliation(s)
- Sofia Kajouj
- Laboratoire de Chimie Organique et Photochimie, Université libre de Bruxelles, Avenue F.D. Roosevelt 50, CP 160/08, 1050 Bruxelles, Belgium
| | - Lionel Marcelis
- Laboratoire de Chimie Organique et Photochimie, Université libre de Bruxelles, Avenue F.D. Roosevelt 50, CP 160/08, 1050 Bruxelles, Belgium.,Engineering of Molecular NanoSystems, Ecole Polytechnique de Bruxelles, Université libre de Bruxelles (ULB), Avenue F.D. Roosevelt 50, CP165/64, B-1050 Brussels, Belgium
| | - Alice Mattiuzzi
- Laboratoire de Chimie Organique, Université libre de Bruxelles, Avenue F.D. Roosevelt 50, CP 160/06, 1050 Bruxelles, Belgium
| | - Adrien Grassin
- Université Grenoble Alpes, Département de Chimie Moléculaire UMR CNRS 5250, CS 40700, 38058 Grenoble Cedex 09, France
| | - Damien Dufour
- Analytical Platform of the Faculty of Pharmacy, Université libre de Bruxelles, Boulevard du Triomphe, Campus de la Plaine, CP205/05, 1050 Bruxelles, Belgium
| | - Pierre Van Antwerpen
- Analytical Platform of the Faculty of Pharmacy, Université libre de Bruxelles, Boulevard du Triomphe, Campus de la Plaine, CP205/05, 1050 Bruxelles, Belgium
| | - Didier Boturyn
- Université Grenoble Alpes, Département de Chimie Moléculaire UMR CNRS 5250, CS 40700, 38058 Grenoble Cedex 09, France
| | - Eric Defrancq
- Université Grenoble Alpes, Département de Chimie Moléculaire UMR CNRS 5250, CS 40700, 38058 Grenoble Cedex 09, France
| | - Mathieu Surin
- Laboratory for Chemistry of Novel Materials, Center for Innovation and Research in Materials and Polymers, University of Mons - UMONS, 20, Place du Parc, B-7000 Mons, Belgium
| | - Julien De Winter
- Organic synthesis and Mass Spectrometry Laboratory, University of Mons - UMONS, Place du Parc 23, B-7000 Mons, Belgium
| | - Pascal Gerbaux
- Organic synthesis and Mass Spectrometry Laboratory, University of Mons - UMONS, Place du Parc 23, B-7000 Mons, Belgium
| | - Ivan Jabin
- Laboratoire de Chimie Organique, Université libre de Bruxelles, Avenue F.D. Roosevelt 50, CP 160/06, 1050 Bruxelles, Belgium
| | - Cécile Moucheron
- Laboratoire de Chimie Organique et Photochimie, Université libre de Bruxelles, Avenue F.D. Roosevelt 50, CP 160/08, 1050 Bruxelles, Belgium
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Flamme M, Clarke E, Gasser G, Hollenstein M. Applications of Ruthenium Complexes Covalently Linked to Nucleic Acid Derivatives. Molecules 2018; 23:E1515. [PMID: 29932443 PMCID: PMC6099586 DOI: 10.3390/molecules23071515] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 06/19/2018] [Accepted: 06/20/2018] [Indexed: 11/16/2022] Open
Abstract
Oligonucleotides are biopolymers that can be easily modified at various locations. Thereby, the attachment of metal complexes to nucleic acid derivatives has emerged as a common pathway to improve the understanding of biological processes or to steer oligonucleotides towards novel applications such as electron transfer or the construction of nanomaterials. Among the different metal complexes coupled to oligonucleotides, ruthenium complexes, have been extensively studied due to their remarkable properties. The resulting DNA-ruthenium bioconjugates have already demonstrated their potency in numerous applications. Consequently, this review focuses on the recent synthetic methods developed for the preparation of ruthenium complexes covalently linked to oligonucleotides. In addition, the usefulness of such conjugates will be highlighted and their applications from nanotechnologies to therapeutic purposes will be discussed.
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Affiliation(s)
- Marie Flamme
- Laboratory for Inorganic Chemical Biology, Chimie ParisTech, PSL University, F-75005 Paris, France.
- Laboratory for Bioorganic Chemistry of Nucleic Acids, Department of Structural Biology and Chemistry, Institute Pasteur, CNRS UMR3523, 28, rue du Docteur Roux, 75724 Paris Cedex 15, France.
| | - Emma Clarke
- Laboratory for Inorganic Chemical Biology, Chimie ParisTech, PSL University, F-75005 Paris, France.
- Laboratory for Bioorganic Chemistry of Nucleic Acids, Department of Structural Biology and Chemistry, Institute Pasteur, CNRS UMR3523, 28, rue du Docteur Roux, 75724 Paris Cedex 15, France.
| | - Gilles Gasser
- Laboratory for Inorganic Chemical Biology, Chimie ParisTech, PSL University, F-75005 Paris, France.
| | - Marcel Hollenstein
- Laboratory for Bioorganic Chemistry of Nucleic Acids, Department of Structural Biology and Chemistry, Institute Pasteur, CNRS UMR3523, 28, rue du Docteur Roux, 75724 Paris Cedex 15, France.
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