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Wen Y, Wang J, Zheng W, Zhu J, Song X, Chen T, Zhang M, Huang Z, Li J. A supramolecular colloidal system based on folate-conjugated β-cyclodextrin polymer and indocyanine green for enhanced tumor-targeted cell imaging in 2D culture and 3D tumor spheroids. J Colloid Interface Sci 2024; 667:259-268. [PMID: 38636227 DOI: 10.1016/j.jcis.2024.04.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/04/2024] [Accepted: 04/10/2024] [Indexed: 04/20/2024]
Abstract
Indocyanine green (ICG) is an FDA-approved medical diagnostic agent that is widely used as a near-infrared (NIR) fluorescent imaging molecular probe. However, ICG tends to aggregate to form dimers or H-aggregates in water and lacks physical and optical stability, which greatly decreases its absorbance and fluorescence intensity in various applications. Additionally, ICG has no tissue- or tumor-targeting properties, and its structure is not easy to modify, which has further limited its application in cancer diagnosis. In this study, we addressed these challenges by developing a supramolecular colloidal carrier system that targets tumor cells. To this end, we synthesized a water-soluble β-cyclodextrin (β-CD) polymer conjugated with folate (FA), denoted PCD-FA, which is capable of forming inclusion complexes with ICG in water through host-guest interactions between the β-CD moieties and ICG molecules. The inclusion complexes formed by PCD-FA and ICG, called ICG@PCD-FA, dispersed stably in solution as colloidal nanoparticles, greatly improving the physical and optical properties of ICG by preventing ICG dimer formation, where ICG appeared as monomers and even J-aggregates. This resulted in stronger and more stable absorption at a longer wavelength of 900 nm, which may allow for deeper tissue penetration and imaging with reduced interference from biological tissues' autofluorescence. Moreover, ICG@PCD-FA showed a targeting effect on folate receptor-positive (FR+) tumor cells, which specifically highlighted FR+ cells via NIR endoscopic imaging. Notably, ICG@PCD-FA further improved permeation and accumulation in FR+ 3D tumor spheroids. Therefore, this ICG@PCD-FA supramolecular colloidal system may have a great potential for use in tumor NIR imaging and diagnostic applications.
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Affiliation(s)
- Yuting Wen
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore; National University of Singapore (Suzhou) Research Institute, Suzhou, Jiangsu 215000, China; National University of Singapore (Chongqing) Research Institute, Yubei District, Chongqing 401120, China
| | - Jianfeng Wang
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore
| | - Wei Zheng
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore
| | - Jingling Zhu
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore; NUS Environmental Research Institute (NERI), National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore
| | - Xia Song
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore
| | - Taili Chen
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore
| | - Miao Zhang
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore
| | - Zhiwei Huang
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore; NUS Environmental Research Institute (NERI), National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore.
| | - Jun Li
- Department of Biomedical Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore; National University of Singapore (Suzhou) Research Institute, Suzhou, Jiangsu 215000, China; National University of Singapore (Chongqing) Research Institute, Yubei District, Chongqing 401120, China; NUS Environmental Research Institute (NERI), National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore.
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Photochemical properties of new bis-cyanine dye as a promising agent for in vivo imaging. MENDELEEV COMMUNICATIONS 2020. [DOI: 10.1016/j.mencom.2020.07.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Egorov AE, Kostyukov AA, Nekipelova TD, Radchenko AS, Shibaeva AV, Klimovich MA, Borissevitch IE, Kuzmin VA. Photoreduction of the Triplet State of Biscarbocyanine Dye. HIGH ENERGY CHEMISTRY 2020. [DOI: 10.1134/s001814392002006x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Mo S, Zhang X, Hameed S, Zhou Y, Dai Z. Glutathione-responsive disassembly of disulfide dicyanine for tumor imaging with reduction in background signal intensity. Theranostics 2020; 10:2130-2140. [PMID: 32104501 PMCID: PMC7019170 DOI: 10.7150/thno.39673] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 12/10/2019] [Indexed: 01/08/2023] Open
Abstract
Near-infrared (NIR) fluorescence imaging has been proved as an effective modality in identifying the tumor border and distinguishing the tumor cells from healthy tissue during the oncological surgery. Developing NIR fluorescent probes with high tumor to background (T/B) signal is essential for the complete debulking of the tumor, which will prolong the survival rate of tumor patients. However, the nonspecific binding and "always-on" properties of the conventional fluorescent probes leads to high background signals and poor specificity. Method: To address this problem, glutathione (GSH)-responsive, two disulfide-bonded dicyanine dyes (ss-diCy5 and ss-diNH800CW) were synthesized. As synthesized dyes are quenched under normal physiological conditions, however, once reached to the tumor site, these dyes are capable of emitting strong fluorescence signals primarily because of the cleavage of the disulfide bond in the tumor microenvironment with high GSH concentration. Besides, the GSH-responsive behavior of these dyes was monitored using the UV-vis and fluorescence spectroscopy. The diagnostic accuracy of the aforementioned dyes was also tested both in tumor cells and 4T1-bearing mice. Results: The fluorescence signal intensity of disulfide dicyanine dyes was quenched up to 89% compared to the mono cyanine dyes, thus providing a very low fluorescence background. However, when the disulfide dicyanine dye reaches the tumor site, the dicyanine is cleaved by GSH into two mono-dyes with high fluorescence strength, thus producing strong fluorescent signals upon excitation. The fluorescent signal of the dicyanine was enhanced by up to 27-fold after interacting with the GSH solution. In vivo xenografts tumor studies further revealed that the fluorescence signals of aforementioned dyes can be quickly recovered in the solid tumor. Conclusion: In summary, the disulfide dicyanines dyes can provide a promising platform for specific tumor-activatable fluorescence imaging with improved T/B value.
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Affiliation(s)
- Shanyan Mo
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100124, China
| | - Xiaoting Zhang
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Sadaf Hameed
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Yiming Zhou
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Zhifei Dai
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
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Kostyukov AA, Nekipelova TD, Borissevitch IE, Kuzmin VA. Interaction of the Triplet State of Biscarbocyanine Dye with a Nitroxyl Radical. HIGH ENERGY CHEMISTRY 2019. [DOI: 10.1134/s0018143919080022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Dichiara M, Prezzavento O, Marrazzo A, Pittalà V, Salerno L, Rescifina A, Amata E. Recent advances in drug discovery of phototherapeutic non-porphyrinic anticancer agents. Eur J Med Chem 2017; 142:459-485. [DOI: 10.1016/j.ejmech.2017.08.070] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/29/2017] [Accepted: 08/31/2017] [Indexed: 12/17/2022]
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Phototransformation of cyanine dye with two chromophores. Effects of oxygen and dye concentration. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.08.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ihmels H, Mahmoud MM, Patrick BO. Optical differentiation between quadruplex DNA and duplex DNA with a [2.2.2]heptamethinecyanine dye. J PHYS ORG CHEM 2017. [DOI: 10.1002/poc.3736] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Heiko Ihmels
- Department of Chemistry and Biology; University of Siegen; Siegen Germany
- Center of Micro- and Nanochemistry and Engineering; University of Siegen; Siegen Germany
| | - Mohamed M.A. Mahmoud
- Department of Chemistry and Biology; University of Siegen; Siegen Germany
- Center of Micro- and Nanochemistry and Engineering; University of Siegen; Siegen Germany
| | - Brian O. Patrick
- Department of Chemistry; University of British Columbia; Vancouver Canada
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Amado AM, Pazin WM, Ito AS, Kuzmin VA, Borissevitch IE. Acridine orange interaction with DNA: Effect of ionic strength. Biochim Biophys Acta Gen Subj 2017; 1861:900-909. [DOI: 10.1016/j.bbagen.2017.01.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 12/31/2016] [Accepted: 01/09/2017] [Indexed: 10/20/2022]
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Kostyukov AA, Nekipelova TD, Radchenko AS, Golovina GV, Klimovich ON, Shtil’ AA, Codognato DCK, Gonçalves PJ, Pavanelli ALS, Ferreira LP, Amado AM, Borisevich YE, Kuzmin VA. Triplet states of the complexes of biscarbocyanine dye with albumin. HIGH ENERGY CHEMISTRY 2017. [DOI: 10.1134/s0018143917020072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kurutos A, Ryzhova O, Tarabara U, Trusova V, Gorbenko G, Gadjev N, Deligeorgiev T. Novel synthetic approach to near-infrared heptamethine cyanine dyes and spectroscopic characterization in presence of biological molecules. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2016.05.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Murakami LS, Ferreira LP, Santos JS, da Silva RS, Nomizo A, Kuz'min VA, Borissevitch IE. Photocytotoxicity of a cyanine dye with two chromophores toward melanoma and normal cells. Biochim Biophys Acta Gen Subj 2014; 1850:1150-7. [PMID: 25512065 DOI: 10.1016/j.bbagen.2014.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/26/2014] [Accepted: 12/02/2014] [Indexed: 11/18/2022]
Abstract
BACKGROUND Due to high optical absorption, triplet quantum yield and affinity to biological structures bichromophoric cyanine dyes (BCDs) can be considered promising sensitizers for application in photodynamic therapy (PDT). In this work, we report on the study of the BCD photocytotoxicity toward melanoma and normal cells in comparison with that of commercial photosensitizer Photogem®. METHODS The cytotoxic and phototoxic effects were measured by standard tests of cell viability. The drug uptake was obtained by the flow cytometry and optical absorption techniques. The BCD intracellular distribution was obtained by the fluorescence image microscopy using specific organelle markers. RESULTS Both drugs demonstrated increased cytotoxicity under irradiation, while in darkness their cytotoxic effect at concentrations lower than 20 μM after 24 h of incubation did not exceed 20%. For 5 h of incubation, BCD photocytotoxicity in relation to melanoma cells reached 100% already at concentrations below 5 μM, while for normal cells the effect did not exceed 70% even for the 20 μM concentration. It is shown that BCD penetrates into the cells and is located predominantly in perinuclear cytoplasmic structures. CONCLUSIONS The BCD photosensitizing characteristics appear more adequate for application in PDT than that of the actually applied commercial photosensitizer Photogem®. Higher light absorption by BCD in the near IR region and its preferential localization in mitochondria can explain its high photocytotoxicity. GENERAL SIGNIFICANCE BCD can be considered as a new promising photosensitizer class for cancer PDT.
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Affiliation(s)
- L S Murakami
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil
| | - L P Ferreira
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil
| | - J S Santos
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. Prof. Zeferino Vaz s/n, CEP 14040-903 Ribeirão Preto, SP, Brazil
| | - R S da Silva
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. Prof. Zeferino Vaz s/n, CEP 14040-903 Ribeirão Preto, SP, Brazil; Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil
| | - A Nomizo
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. Prof. Zeferino Vaz s/n, CEP 14040-903 Ribeirão Preto, SP, Brazil
| | - V A Kuz'min
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, Kosygin St, 4, 117977 Moscow, Russia
| | - I E Borissevitch
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, CEP 14040-901 Ribeirão Preto, SP, Brazil.
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Fradj AB, Lafi R, Hamouda SB, Gzara L, Hamzaoui AH, Hafiane A. Investigation on the interaction of Safranin T with anionic polyelectrolytes by spectrophotometric method. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 131:169-176. [PMID: 24830630 DOI: 10.1016/j.saa.2014.04.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 03/08/2014] [Accepted: 04/06/2014] [Indexed: 06/03/2023]
Abstract
Understanding the role played by chemical additives such as NaCl salt, acid and Cetylpyridinium Chloride (CPC) surfactant on the interaction between dye and polyelectrolyte contributes to optimization of processes using polyelectrolytes in the removal of dye from aqueous solution. Herein we focus in the interaction between Safranin T, a cationic dye, with two anionic polyelectrolytes, poly(ammonium acrylate) and poly(acrylic acid) using spectrophotometric method and conductivity measurement. In aqueous solution, each of anionic polyelectrolytes forms a complex with the dye and induces a metachromasy indicated by the blue shift of the absorbance of the dye. The stoichiometry of complexes evaluated by the molar ratio method are 1:1 for Safranin T poly(ammonium acrylate) and 2:1 in the case of Safranin T poly(acrylic acid). The effect of additives on the stability of complexes has been studied by varying concentrations of the salt and the surfactant and pH of the solution. The thermodynamic parameters of interaction ΔG, ΔH and ΔS at different temperatures were evaluated to determine the stability constant of the complexes.
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Affiliation(s)
- Anouar Ben Fradj
- Laboratory of Wastewater Treatment, CERTE, BP 273, Soliman 8020, Tunisia; Laboratory of Valorisation of Materials, CNRSM, BP 95, Hammam-Lif 2050, Tunisia.
| | - Ridha Lafi
- Laboratory of Wastewater Treatment, CERTE, BP 273, Soliman 8020, Tunisia
| | | | - Lassaad Gzara
- Center of Excellence in Desalination Technology, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Amor Hafiane
- Laboratory of Wastewater Treatment, CERTE, BP 273, Soliman 8020, Tunisia.
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Oxidative cleavage of DNA by pentamethine carbocyanine dyes irradiated with long-wavelength visible light. Bioorg Med Chem Lett 2013; 24:214-9. [PMID: 24332091 DOI: 10.1016/j.bmcl.2013.11.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/14/2013] [Accepted: 11/15/2013] [Indexed: 12/26/2022]
Abstract
Here we report the synthesis of seven symmetrical carbocyanine dyes in which two nitrogen-substituted benz[e]indolium rings are joined by a pentamethine bridge that is meso-substituted with chlorine or bromine versus hydrogen. The heteroatom of benz[e]indolium is modified with a phenylpropyl, methyl, or cationic quaternary ammonium group. In reactions containing micro molar concentrations of halogenated dye, irradiation at 575, 588, 623, or 700nm produces good photocleavage of plasmid DNA. UV-visible spectra show that the carbocyanines are in their H-aggregated and monomeric forms. Scavenger experiments point to the involvement of singlet oxygen and hydroxyl radicals in DNA photocleavage.
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Wang C, Yuan Y, Tian X, Sun J, Shao H, Sun Z. A theoretical study on the structural dependences of third-order optical nonlinearities of heterocycle-substituted polymethine cyanine chromophores. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.07.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
The interactions of a triangle-shaped [2.2.2]heptamethinecyanine dye 1, namely 1,5,7-tris-[3-methylbenzothiazol-2-yl]-[2.2.2]heptamethindiium, with quadruplex DNA were studied with photometric and fluorimetric titrations, thermal DNA denaturation, CD and (1)H-NMR spectroscopy. The ligand binds to the quadruplex DNA with moderate affinity (K = 8 × 10(5) M(-1)), mainly by terminal π stacking. Remarkably, the ligand 1 exhibits a selectivity for quadruplex DNA relative to duplex DNA. Whereas the cyanine dye is very weakly fluorescent in aqueous solution, the emission intensity increases by a factor of >100 upon association with quadruplex DNA. Thus, it is shown that trinuclear cyanine derivatives may be employed as selective probes for the fluorimetric detection of quadruplex DNA.
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Affiliation(s)
- Heiko Ihmels
- University of Siegen, Organic Chemistry II, Adolf-Reichwein-Str. 2, D-57068, Siegen, Germany.
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Polymethine dyes as spectral-fluorescent probes for biomacromolecules. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2012. [DOI: 10.1016/j.jphotochemrev.2011.11.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Losytskyy MY, Yashchuk VM. Fluorescent J-Aggregates and Their Biological Applications. ACTA ACUST UNITED AC 2010. [DOI: 10.1007/978-3-642-04701-5_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Schaberle FA, Galembeck SE, Borissevitch IE. Computational study of steric and spectroscopic characteristics of bi-chromophoric cyanine dyes: comparison with experimental data. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 72:863-867. [PMID: 19155190 DOI: 10.1016/j.saa.2008.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2008] [Revised: 11/18/2008] [Accepted: 12/08/2008] [Indexed: 05/27/2023]
Abstract
The spectral and energetic characteristics of four bi-chromophoric cyanine dyes (BCDs) which possess angles between chromophores 180 degrees , 150 degrees , 120 degrees and 90 degrees , were studied using quantum chemical calculations in comparison with experimental data. It was demonstrated that for BCD with 180 degrees , 150 degrees and 90 degrees trans-trans isomers possess the lowest energy, while for BCD with 120 degrees the trans-trans and cis-trans isomers have comparable energies and in the temperature range from 273K up to 373K both isomers of this dye are present. It was also demonstrated that the splitting of the spectra of cyanine dyes with two chromophores (BCD) was determined by two effects: the dipole-dipole chromophore interaction and the electron tunneling through the central heterocycle. Both effects depend on the central heterocycle structure, which on the one hand determines the distance between the chromophores, thus determining the value of the dipole-dipole interaction, and on the other hand the degree of pi-conjugation in the central heterocycle determines the probability of electron tunneling. The central heterocycle structure determines relative orientation of the chromophore dipoles, as well, thus determining the intensities of the short-wavelength and long-wavelength bands in the BCD absorption spectra.
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Affiliation(s)
- Fábio António Schaberle
- Departamento de Física e Matemática, Universidade de São Paulo, Monte Alegre, Ribeirão Preto, SP, Brazil
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Affiliation(s)
- Guy A Hembury
- Japan Science and Technology Agency and Department of Applied Chemistry, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan
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