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Liu B, Najari A, Pan C, Leclerc M, Xiao D, Zou Y. New Low Bandgap Dithienylbenzothiadiazole Vinylene Based Copolymers: Synthesis and Photovoltaic Properties. Macromol Rapid Commun 2009; 31:391-8. [DOI: 10.1002/marc.200900654] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 10/05/2009] [Indexed: 11/09/2022]
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103
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Leclerc M, Najari A, Beaupré S. 2008 Macromolecular Science and Engineering Division Award Lecture — Conjugated polymers: From micro-electronics to genomics. CAN J CHEM 2009. [DOI: 10.1139/v09-086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Conjugated polymers have received a lot of attention, since they combine the best features of metals or semiconductors with those of synthetic polymers. For instance, solar cells based on poly(2,7-carbazole) derivatives have revealed power-conversion efficiencies up to 6%. This class of materials could lead to printable and flexible photovoltaic devices. Moreover, water-soluble luminescent polythiophenes have allowed the specific, rapid, and ultra-sensitive detection of unlabelled DNA, RNA, or proteins. This new optical detection mechanism is based on electrostatic interactions between a cationic polythiophene derivative and negatively charged oligonucleotides. This method makes now possible the rapid assessment of the identity of single nucleotide polymorphisms (SNPs), genes, and pathogens without the need for nucleic acid amplification.
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Zou Y, Gendron D, Neagu-Plesu R, Leclerc M. Synthesis and Characterization of New Low-Bandgap Diketopyrrolopyrrole-Based Copolymers. Macromolecules 2009. [DOI: 10.1021/ma901114j] [Citation(s) in RCA: 159] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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105
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Zou Y, Gendron D, Badrou-Aïch R, Najari A, Tao Y, Leclerc M. A High-Mobility Low-Bandgap Poly(2,7-carbazole) Derivative for Photovoltaic Applications. Macromolecules 2009. [DOI: 10.1021/ma900364c] [Citation(s) in RCA: 223] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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106
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Desmecht D, Bergh RV, Sartelet A, Leclerc M, Mignot C, Misse F, Sudraud C, Berthemin S, Jolly S, Mousset B, Linden A, Coignoul F, Cassart D. Evidence for transplacental transmission of the current wild-type strain of bluetongue virus serotype 8 in cattle. Vet Rec 2009; 163:50-2. [PMID: 18621997 DOI: 10.1136/vr.163.2.50] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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107
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Muñoz-Tamayo R, Laroche B, Leclerc M, Walter E. IDEAS: a Parameter Identification Toolbox with Symbolic Analysis of Uncertainty and its Application to Biological Modelling. ACTA ACUST UNITED AC 2009. [DOI: 10.3182/20090706-3-fr-2004.00211] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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108
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Doré K, Leclerc M, Boudreau D. Fluorescence Signal Amplification for Ultrasensitive DNA Detection. REVIEWS IN FLUORESCENCE 2009. [DOI: 10.1007/978-0-387-88722-7_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Boudreault PLT, Wakim S, Tang ML, Tao Y, Bao Z, Leclerc M. New indolo[3,2-b]carbazole derivatives for field-effect transistor applications. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b900271e] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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110
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Wakim S, Beaupré S, Blouin N, Aich BR, Rodman S, Gaudiana R, Tao Y, Leclerc M. Highly efficient organic solar cells based on a poly(2,7-carbazole) derivative. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b901302d] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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111
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Le Bouch N, Auger M, Leclerc M. Structure and Segmental Motions in a Substituted Polythiophene: A Solid-State NMR Study. MACROMOL CHEM PHYS 2008. [DOI: 10.1002/macp.200800365] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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112
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Bellows D, Gingras É, Aly SM, Abd-El-Aziz AS, Leclerc M, Harvey PD. Organometallic and Conjugated Organic Polymers Held Together by Strong Electrostatic Interactions to Form Luminescent Hybrid Materials. Inorg Chem 2008; 47:11720-33. [DOI: 10.1021/ic801461j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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113
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Leclerc M, Raby B, Laberge F, Fournier B, Martin S, Lacasse Y. Concurrent Chemoradiotherapy in Locally Advanced Non-small Cell Lung Cancer: Comparison of Two Treatment Regimens. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Conjugated polymers combine the interesting optical and electrical properties of metals with the processing advantages and mechanical properties of traditional synthetic polymers. With clever use of a variety of synthetic tools, researchers have prepared highly pure polymers with optimized physical properties during the past 30 years. For example, the synthesis of well-defined polyacetylenes, polyphenylenes, polythiophenes, polyfluorenes, and other conjugated polymers have significantly improved the performance of these polymeric materials. However, one important class of conjugated polymers was missing from this chemical inventory: easy access to well-defined poly(2,7-carbazole)s and related polymers. This Account highlights advances in the synthesis of poly(2,7-carbazole) derivatives since they were first reported in 2001. Starting from 2-nitro-biphenyl derivatives, 2,7-functionalized carbazoles are typically obtained from Cadogan ring-closure reactions. In a second step, Yamamoto, Stille, Suzuki, or Horner-Emmons coupling polymerization leads to various poly(2,7-carbazole) derivatives. We discuss the characterization of their optical and electrical properties with a strong emphasis on the structure-property relationships. In addition, we carefully evaluate these polymers as active components in light-emitting diodes, transistors, and photovoltaic cells. In particular, several low band gap poly(2,7-carbazole) derivatives have revealed highly promising features for solar cell applications with hole mobilities of about 3 x 10(-3) cm2 V(-1) s(-1) and power conversion efficiencies up to 4.8%. Finally, we show how these new synthetic strategies have led to the preparation of novel poly(heterofluorene) derivatives and ladder-type conjugated polymers.
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Wakim S, Aïch B, Tao Y, Leclerc M. Charge Transport, Photovoltaic, and Thermoelectric Properties of Poly(2,7‐Carbazole) and Poly(Indolo[3,2‐b]Carbazole) Derivatives. POLYM REV 2008. [DOI: 10.1080/15583720802231726] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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116
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Leclerc M, Bernalier A, Donadille G, Lelait M. H2/CO2 metabolism in acetogenic bacteria isolated from the human colon. Anaerobe 2008; 3:307-15. [PMID: 16887606 DOI: 10.1006/anae.1997.0117] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/1997] [Accepted: 07/17/1997] [Indexed: 11/22/2022]
Abstract
The present work reports on autotrophic metabolism in four H2/CO2-utilizing acetogenic bacteria isolated from the human colon (two Clostridium species, one Streptococcus species, and Ruminococcus hydrogenotrophicus). H2/CO2-utilization by these human acetogenic strains occurred during both exponential and stationary phases of growth. Acetate was the major metabolite produced by all isolates following the stoichiometric equation of reductive acetogenesis. Furthermore, the ability of these acetogenic bacteria to incorporate 13CO2 into acetate in the presence of H2 in the gas phase demonstrated the utilization of the reductive pathway of acetate formation from a one-carbon compound. Energy conservation during the autotrophic metabolism in colonic acetogens might involve sodium- or proton-chemiosmotic mechanisms. A sodium-dependent ATP generation was only demonstrated in one Clostridium species, whereas sodium could be replaced by potassium in other strains. The minimal thresholds of hydrogen uptake were determined and varied from 1100 to 3680 ppm depending on the acetogenic strain. These values appeared higher than those measured for the colonic methanogen,Methanobrevibacter smithii.
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Lepage P, Colombet J, Marteau P, Sime-Ngando T, Doré J, Leclerc M. Dysbiosis in inflammatory bowel disease: a role for bacteriophages? Gut 2008; 57:424-5. [PMID: 18268057 DOI: 10.1136/gut.2007.134668] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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118
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Ho HA, Najari A, Leclerc M. Optical detection of DNA and proteins with cationic polythiophenes. Acc Chem Res 2008; 41:168-78. [PMID: 18198841 DOI: 10.1021/ar700115t] [Citation(s) in RCA: 387] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In recent years, intense research has been carried out worldwide with the goal of developing simple, sensitive, and specific detection tools for biomedical applications. Along these lines, we reported in 2002 on cationic polythiophene derivatives able to provide ultrasensitive detection levels and the capability to distinguish perfect matches from oligonucleotides having as little as a single base mismatch. It was shown that the intrinsic fluorescence of the random-coil polymers quenches as a result of the planar, highly conjugated conformation adopted by the polymers when complexed with a single-strand DNA (ssDNA) capture probe but increases again after hybridization with the perfectly matched complementary strand. This change in fluorescence intensity is mainly due to a modification in the delocalization of pi electrons along the carbon chain backbone that occurs when switching between the two conformations. Thus, by monitoring, via the change in fluorescence intensity, the hybridization of the complementary ssDNA target with the "duplex", one could detect as little as 220 complementary target molecules in a 150 microL sample volume (0.36 zmol) in less than 1 hour. Building on this initial concept, we then reported that tagging the DNA probe with a suitable fluorophore dramatically increases the detection sensitivity. This novel molecular system involves the self-assembly of aggregates of duplexes in solution, prior to the introduction of the target, which allows a highly efficient resonance energy transfer (RET) between a "donor" (being the complex formed of the DNA double helix and the polymer chain wrapped around it) and a large number of neighboring "acceptors" (the fluorophores attached to the DNA probes). The massive intrinsic signal amplification (fluorescence chain reaction or FCR) provided by this novel integrated molecular system allows the specific detection of as little as five dsDNA copies in a 3 mL sample volume in only 5 minutes, without the need for prior amplification of the target. Clearly, direct and reliable detection of DNA hybridization without prior PCR amplification or chemical tagging of the genetic target is now possible with this methodology. We have also shown that proteins can be detected following a similar strategy. Impressive results have also been reported by direct and specific staining of targeted proteins. All these features have recently allowed the development of responsive polymeric supports for the detection of DNA and proteins. All these assays that do not require any chemical manipulation of the biological targets or sophisticated experimental procedures should soon lead to major advances in genomics and proteomics.
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Blouin N, Michaud A, Gendron D, Wakim S, Blair E, Neagu-Plesu R, Belletête M, Durocher G, Tao Y, Leclerc M. Toward a rational design of poly(2,7-carbazole) derivatives for solar cells. J Am Chem Soc 2007; 130:732-42. [PMID: 18095689 DOI: 10.1021/ja0771989] [Citation(s) in RCA: 1277] [Impact Index Per Article: 75.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
On the basis of theoretical models and calculations, several alternating polymeric structures have been investigated to develop optimized poly(2,7-carbazole) derivatives for solar cell applications. Selected low band gap alternating copolymers have been obtained via a Suzuki coupling reaction. A good correlation between DFT theoretical calculations performed on model compounds and the experimental HOMO, LUMO, and band gap energies of the corresponding polymers has been obtained. This study reveals that the alternating copolymer HOMO energy level is mainly fixed by the carbazole moiety, whereas the LUMO energy level is mainly related to the nature of the electron-withdrawing comonomer. However, solar cell performances are not solely driven by the energy levels of the materials. Clearly, the molecular weight and the overall organization of the polymers are other important key parameters to consider when developing new polymers for solar cells. Preliminary measurements have revealed hole mobilities of about 1 x 10(-3) cm2 x V(-1) x s(-1) and a power conversion efficiency (PCE) up to 3.6%. Further improvements are anticipated through a rational design of new symmetric low band gap poly(2,7-carbazole) derivatives.
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Belletête M, Boudreault PLT, Leclerc M, Durocher G. Investigation of the structure, the optical properties, and the photophysics of some indolocarbazoles having terminal aromatic rings. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.theochem.2007.08.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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121
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Boudreault PLT, Michaud A, Leclerc M. A New Poly(2,7-Dibenzosilole) Derivative in Polymer Solar Cells. Macromol Rapid Commun 2007. [DOI: 10.1002/marc.200700470] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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122
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Wakim S, Blouin N, Gingras E, Tao Y, Leclerc M. Poly(2,7-carbazole) Derivatives as Semiconductors for Organic Thin-Film Transistors. Macromol Rapid Commun 2007. [DOI: 10.1002/marc.200700307] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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123
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124
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Boudreault PLT, Wakim S, Blouin N, Simard M, Tessier C, Tao Y, Leclerc M. Synthesis, Characterization, and Application of Indolo[3,2-b]carbazole Semiconductors. J Am Chem Soc 2007; 129:9125-36. [PMID: 17602481 DOI: 10.1021/ja071923y] [Citation(s) in RCA: 196] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis, characterization, and field-effect transistor (FET) properties of new indolo[3,2-b]carbazoles are described. In particular, an extensive characterization of their crystal structures has revealed the importance of the nature of the side chains (alkyl, phenyl, thienyl substituents) on their solid-state organization. These organic materials have exhibited p-type FET behavior with hole mobilities as high as 0.2 cm2 V(-1) s(-1) with an on/off current ratio higher than 10(6). Best results were obtained with phenyl-substituted indolo[3,2-b]carbazoles since the presence of phenyl substituents seems to allow efficient overlap between the oligomeric molecules. More importantly, FET properties were kept constant during several months in air.
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Le Floch F, Ho HA, Leclerc M. Label-free electrochemical detection of protein based on a ferrocene-bearing cationic polythiophene and aptamer. Anal Chem 2007; 78:4727-31. [PMID: 16808489 DOI: 10.1021/ac0521955] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two label-free electrochemical methods for the detection of human alpha-thrombin using a water-soluble, ferrocene-functionalized polythiophene transducer and a single-stranded oligonucleotide aptamer probe are described. The first approach is a direct method in which the recorded current decreases upon addition of the targeted protein. The second one requires more steps and the additional utilization of PNA probes and nuclease enzyme. This indirect method leads to an increase of the electrical signal as a function of the concentration of human alpha-thrombin with a detection limit of 75 fmol.
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