51
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Paulin JV, Veiga AG, Garcia-Basabe Y, Rocco MLM, Graeff CFO. Structural and optical properties of soluble melanin analogues with enhanced photoluminescence quantum efficiency. POLYM INT 2018. [DOI: 10.1002/pi.5543] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- João Vitor Paulin
- São Paulo State University (UNESP), Post-Graduate Program in Materials Science and Technology; Bauru Brazil
| | - Amanda Garcez Veiga
- Institute of Chemistry; Federal University of Rio de Janeiro; Rio de Janeiro Brazil
| | - Yunier Garcia-Basabe
- Institute of Chemistry; Federal University of Rio de Janeiro; Rio de Janeiro Brazil
| | | | - Carlos FO Graeff
- São Paulo State University (UNESP), Post-Graduate Program in Materials Science and Technology; Bauru Brazil
- São Paulo State University (UNESP), Department of Physics; Bauru Brazil
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52
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Fang YG, Li CX, Chang XP, Cui G. Photophysics of a UV-B Filter 4-Methylbenzylidene Camphor: Intersystem Crossing Plays an Important Role. Chemphyschem 2018; 19:744-752. [PMID: 29288547 DOI: 10.1002/cphc.201701230] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 12/29/2017] [Indexed: 11/07/2022]
Abstract
4-Methylbenzylidene camphor (4MBC) is a frequently used ultraviolet (UV) filter in commercial sunscreens, which is experimentally found to undergo efficient intersystem crossing to triplet manifolds followed by predominant radiationless decay to the ground state. However, its photophysical mechanism is unclear. Herein, we have employed combined CASPT2 and CASSCF methods to study the spectroscopic properties, geometric and electronic structures, conical intersections and crossing points, and excited-state deactivation channels of 4MBC. We have found that the V(1 ππ*) state is populated with large probability in the Franck-Condon region. Starting from this state, there are two efficient nonradiative relaxation processes to populate the 3 ππ* state. In the first one, the V(1 ππ*) state decays to the V'(1 ππ*) state. The resultant V'(1 ππ*) state further jumps to the 1 nπ* state by internal conversion at the 1 ππ*/1 nπ* conical intersection. Then, the 1 nπ* state hops to the 3 ππ* state through an efficient 1 nπ*→3 ππ* intersystem crossing process. In the second one, the V(1 ππ*) state can diabatically relax along the photoisomerization reaction coordinate. In this process, a 1 ππ*/3 nπ* crossing point helps the 1 ππ* system decay to the 3 nπ* state, which further decays to the 3 ππ* state through internal conversion at the 3 nπ*/3 ππ* conical intersection. Once the 3 ππ* state is formed, a nearly barrierless relaxation path drives the 3 ππ* system to hop to the S0 state via the 3 ππ*/S0 crossing point. Our current work not only rationalizes recent experimental observations but also enriches our photophysical knowledge of UV filters.
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Affiliation(s)
- Ye-Guang Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Chun-Xiang Li
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang, 464000, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
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53
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Sherin PS, Tsentalovich YP, Vauthey E, Benassi E. Ultrafast excited state decay of natural UV filters: from intermolecular hydrogen bonds to a conical intersection. Phys Chem Chem Phys 2018; 20:15074-15085. [DOI: 10.1039/c8cp02183j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An unsaturated bond in the side chain leads to the ultrafast decay of the excited statesviaa conical intersection independent of solvent properties.
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Affiliation(s)
- Peter S. Sherin
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Yuri P. Tsentalovich
- International Tomography Center SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Eric Vauthey
- Department of Physical Chemistry
- University of Geneva
- Geneva
- Switzerland
| | - Enrico Benassi
- Novosibirsk State University
- Novosibirsk
- Russia
- School of Science and Technology
- Nazarbayev University
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54
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Xiao M, Hu Z, Wang Z, Li Y, Tormo AD, Le Thomas N, Wang B, Gianneschi NC, Shawkey MD, Dhinojwala A. Bioinspired bright noniridescent photonic melanin supraballs. SCIENCE ADVANCES 2017; 3:e1701151. [PMID: 28929137 PMCID: PMC5600532 DOI: 10.1126/sciadv.1701151] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 08/17/2017] [Indexed: 05/20/2023]
Abstract
Structural colors enable the creation of a spectrum of nonfading colors without pigments, potentially replacing toxic metal oxides and conjugated organic pigments. However, significant challenges remain to achieve the contrast needed for a complete gamut of colors and a scalable process for industrial application. We demonstrate a feasible solution for producing structural colors inspired by bird feathers. We have designed core-shell nanoparticles using high-refractive index (RI) (~1.74) melanin cores and low-RI (~1.45) silica shells. The design of these nanoparticles was guided by finite-difference time-domain simulations. These nanoparticles were self-assembled using a one-pot reverse emulsion process, which resulted in bright and noniridescent supraballs. With the combination of only two ingredients, synthetic melanin and silica, we can generate a full spectrum of colors. These supraballs could be directly added to paints, plastics, and coatings and also used as ultraviolet-resistant inks or cosmetics.
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Affiliation(s)
- Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Ziying Hu
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Zhao Wang
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yiwen Li
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - Alejandro Diaz Tormo
- Photonics Research Group, Department of Information Technology, Ghent University–imec, Center for Nano- and Biophotonics (NB-Photonics), 9000 Ghent, Belgium
| | - Nicolas Le Thomas
- Photonics Research Group, Department of Information Technology, Ghent University–imec, Center for Nano- and Biophotonics (NB-Photonics), 9000 Ghent, Belgium
| | - Boxiang Wang
- Institute of Engineering Thermophysics, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Nathan C. Gianneschi
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA
- Corresponding author. (A.D.); (M.D.S.); (N.C.G.)
| | - Matthew D. Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, The University of Ghent, 9000 Ghent, Belgium
- Department of Biology and Integrated Bioscience Program, University of Akron, Akron, OH 44325, USA
- Corresponding author. (A.D.); (M.D.S.); (N.C.G.)
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
- Corresponding author. (A.D.); (M.D.S.); (N.C.G.)
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55
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Ghosh P, Ghosh D. Elucidating the Photoprotection Mechanism of Eumelanin Monomers. J Phys Chem B 2017; 121:5988-5994. [DOI: 10.1021/acs.jpcb.7b05123] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Paulami Ghosh
- Physical and Materials Chemistry
Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Debashree Ghosh
- Physical and Materials Chemistry
Division, CSIR-National Chemical Laboratory, Pune 411008, India
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56
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Cecchini MM, Reale S, Manini P, d'Ischia M, De Angelis F. Modeling Fungal Melanin Buildup: Biomimetic Polymerization of 1,8-Dihydroxynaphthalene Mapped by Mass Spectrometry. Chemistry 2017; 23:8092-8098. [DOI: 10.1002/chem.201701951] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Martina Maya Cecchini
- Department of Physical and Chemical Sciences; University of L'Aquila; Via Vetoio Coppito, L'Aquila Italy
| | - Samantha Reale
- Department of Physical and Chemical Sciences; University of L'Aquila; Via Vetoio Coppito, L'Aquila Italy
| | - Paola Manini
- Department of Chemical Sciences, University of Naples “Federico II”-; Faculties of Monte Sant'Angelo; Via Cinthia Naples Italy
| | - Marco d'Ischia
- Department of Chemical Sciences, University of Naples “Federico II”-; Faculties of Monte Sant'Angelo; Via Cinthia Naples Italy
| | - Francesco De Angelis
- Department of Physical and Chemical Sciences; University of L'Aquila; Via Vetoio Coppito, L'Aquila Italy
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57
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Eckert S, Norell J, Miedema PS, Beye M, Fondell M, Quevedo W, Kennedy B, Hantschmann M, Pietzsch A, Van Kuiken BE, Ross M, Minitti MP, Moeller SP, Schlotter WF, Khalil M, Odelius M, Föhlisch A. Untersuchung unabhängiger N‐H‐ und N‐C‐Bindungsverformungen auf ultrakurzen Zeitskalen mit resonanter inelastischer Röntgenstreuung. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700239] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sebastian Eckert
- Institut für Physik und Astronomie Universität Potsdam Karl-Liebknecht-Str. 24/25 14476 Potsdam Deutschland
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Jesper Norell
- Department of Physics Stockholm University AlbaNova University Center 10691 Stockholm Schweden
| | - Piter S. Miedema
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Martin Beye
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Mattis Fondell
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Wilson Quevedo
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Brian Kennedy
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Markus Hantschmann
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | - Annette Pietzsch
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
| | | | - Matthew Ross
- Department of Chemistry University of Washington Seattle WA 98195 USA
| | - Michael P. Minitti
- LCLS SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park CA 94025 USA
| | - Stefan P. Moeller
- LCLS SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park CA 94025 USA
| | - William F. Schlotter
- LCLS SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park CA 94025 USA
| | - Munira Khalil
- Department of Chemistry University of Washington Seattle WA 98195 USA
| | - Michael Odelius
- Department of Physics Stockholm University AlbaNova University Center 10691 Stockholm Schweden
| | - Alexander Föhlisch
- Institut für Physik und Astronomie Universität Potsdam Karl-Liebknecht-Str. 24/25 14476 Potsdam Deutschland
- Institute for Methods and Instrumentation for Synchrotron Radiation Research Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Albert-Einstein-Str. 15 12489 Berlin Deutschland
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58
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Eckert S, Norell J, Miedema PS, Beye M, Fondell M, Quevedo W, Kennedy B, Hantschmann M, Pietzsch A, Van Kuiken BE, Ross M, Minitti MP, Moeller SP, Schlotter WF, Khalil M, Odelius M, Föhlisch A. Ultrafast Independent N-H and N-C Bond Deformation Investigated with Resonant Inelastic X-Ray Scattering. Angew Chem Int Ed Engl 2017; 56:6088-6092. [PMID: 28374523 PMCID: PMC5485001 DOI: 10.1002/anie.201700239] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/16/2017] [Indexed: 01/07/2023]
Abstract
The femtosecond excited-state dynamics following resonant photoexcitation enable the selective deformation of N-H and N-C chemical bonds in 2-thiopyridone in aqueous solution with optical or X-ray pulses. In combination with multiconfigurational quantum-chemical calculations, the orbital-specific electronic structure and its ultrafast dynamics accessed with resonant inelastic X-ray scattering at the N 1s level using synchrotron radiation and the soft X-ray free-electron laser LCLS provide direct evidence for this controlled photoinduced molecular deformation and its ultrashort timescale.
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Affiliation(s)
- Sebastian Eckert
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24/25, 14476, Potsdam, Germany.,Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Jesper Norell
- Department of Physics, Stockholm University, AlbaNova University Center, 10691, Stockholm, Sweden
| | - Piter S Miedema
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Martin Beye
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Mattis Fondell
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Wilson Quevedo
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Brian Kennedy
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Markus Hantschmann
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | - Annette Pietzsch
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
| | | | - Matthew Ross
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Michael P Minitti
- LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Stefan P Moeller
- LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - William F Schlotter
- LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Munira Khalil
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Michael Odelius
- Department of Physics, Stockholm University, AlbaNova University Center, 10691, Stockholm, Sweden
| | - Alexander Föhlisch
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24/25, 14476, Potsdam, Germany.,Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489, Berlin, Germany
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59
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Nogueira JJ, Corani A, El Nahhas A, Pezzella A, d'Ischia M, González L, Sundström V. Sequential Proton-Coupled Electron Transfer Mediates Excited-State Deactivation of a Eumelanin Building Block. J Phys Chem Lett 2017; 8:1004-1008. [PMID: 28195487 DOI: 10.1021/acs.jpclett.6b03012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Skin photoprotection is commonly believed to rely on the photochemistry of 5,6-dihydroxyindole (DHI)- and 5,6-dihydroxyindole-2-carboxylic acid (DHICA)-based eumelanin building blocks. Attempts to elucidate the underlying excited-state relaxation mechanisms have been partly unsuccessful due to the marked instability to oxidation. We report a study of the excited-state deactivation of DHI using steady-state and time-resolved fluorescence accompanied by high-level quantum-chemistry calculations including solvent effects. Spectroscopic data show that deactivation of the lowest excited state of DHI in aqueous buffer proceeds on the 100 ps time scale and is 20 times faster than in methanol. Quantum-chemical calculations reveal that the excited-state decay mechanism is a sequential proton-coupled electron transfer, which involves the initial formation of a solvated electron from DHI, followed by the transfer of a proton to the solvent. This unexpected finding would prompt a revision of current notions about eumelanin photophysics and photobiology.
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Affiliation(s)
- Juan J Nogueira
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna , Währinger Str. 17, A-1090 Wien, Austria
| | - Alice Corani
- Department of Chemical Physics, Lund University , Box 124, 22100 Lund, Sweden
| | - Amal El Nahhas
- Department of Chemical Physics, Lund University , Box 124, 22100 Lund, Sweden
| | - Alessandro Pezzella
- Department of Chemistry and Sciences, University of Naples Federico II , Via Cintia, 80126 Naples, Italy
| | - Marco d'Ischia
- Department of Chemistry and Sciences, University of Naples Federico II , Via Cintia, 80126 Naples, Italy
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna , Währinger Str. 17, A-1090 Wien, Austria
| | - Villy Sundström
- Department of Chemical Physics, Lund University , Box 124, 22100 Lund, Sweden
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60
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Micillo R, Panzella L, Iacomino M, Prampolini G, Cacelli I, Ferretti A, Crescenzi O, Koike K, Napolitano A, d'Ischia M. Eumelanin broadband absorption develops from aggregation-modulated chromophore interactions under structural and redox control. Sci Rep 2017; 7:41532. [PMID: 28150707 PMCID: PMC5288692 DOI: 10.1038/srep41532] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 12/19/2016] [Indexed: 12/18/2022] Open
Abstract
Eumelanins, the chief photoprotective pigments in man and mammals, owe their black color to an unusual broadband absorption spectrum whose origin is still a conundrum. Excitonic effects from the interplay of geometric order and disorder in 5,6-dihydroxyindole (DHI)-based oligomeric/polymeric structures play a central role, however the contributions of structural (scaffold-controlled) and redox (π-electron-controlled) disorder have remained uncharted. Herein, we report an integrated experimental-theoretical entry to eumelanin chromophore dynamics based on poly(vinyl alcohol)-controlled polymerization of a large set of 5,6-dihydroxyindoles and related dimers. The results a) uncover the impact of the structural scaffold on eumelanin optical properties, disproving the widespread assumption of a universal monotonic chromophore; b) delineate eumelanin chromophore buildup as a three-step dynamic process involving the rapid generation of oxidized oligomers, termed melanochromes (phase I), followed by a slow oxidant-independent band broadening (phase II) leading eventually to scattering (phase III); c) point to a slow reorganization-stabilization of melanochromes via intermolecular redox interactions as the main determinant of visible broadband absorption.
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Affiliation(s)
- Raffaella Micillo
- Department of Clinical Medicine and Surgery, University of Naples Federico II, I-80131 Naples, Italy
| | - Lucia Panzella
- Department of Chemical Sciences, University of Naples Federico II, I-80126 Naples, Italy
| | - Mariagrazia Iacomino
- Department of Chemical Sciences, University of Naples Federico II, I-80126 Naples, Italy
| | - Giacomo Prampolini
- Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Area della Ricerca, I-56124 Pisa, Italy
| | - Ivo Cacelli
- Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Area della Ricerca, I-56124 Pisa, Italy.,Dipartimento di Chimica e Chimica Industriale, Università di Pisa, I-56124 Pisa, Italy
| | - Alessandro Ferretti
- Istituto di Chimica dei Composti Organometallici (ICCOM-CNR), Area della Ricerca, I-56124 Pisa, Italy
| | - Orlando Crescenzi
- Department of Chemical Sciences, University of Naples Federico II, I-80126 Naples, Italy
| | - Kenzo Koike
- Hair care Products Research Laboratories, Kao Corporation, Tokyo 131-8501, Japan
| | - Alessandra Napolitano
- Department of Chemical Sciences, University of Naples Federico II, I-80126 Naples, Italy
| | - Marco d'Ischia
- Department of Chemical Sciences, University of Naples Federico II, I-80126 Naples, Italy
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61
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Baker LA, Greenough SE, Stavros VG. A Perspective on the Ultrafast Photochemistry of Solution-Phase Sunscreen Molecules. J Phys Chem Lett 2016; 7:4655-4665. [PMID: 27791379 DOI: 10.1021/acs.jpclett.6b02104] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sunscreens are one of the most common ways of providing on-demand additional photoprotection to the skin. Ultrafast transient absorption spectroscopy has recently proven to be an invaluable tool in understanding how the components of commercial sunscreen products display efficient photoprotection. Important examples of how this technique has unravelled the photodynamics of common components are given in this Perspective, and some of the remaining unanswered questions are discussed.
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Affiliation(s)
- Lewis A Baker
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Simon E Greenough
- Department of Chemistry, University of Sheffield , Sheffield S3 7HF, United Kingdom
| | - Vasilios G Stavros
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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62
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d'Ischia M, Wakamatsu K, Cicoira F, Di Mauro E, Garcia-Borron JC, Commo S, Galván I, Ghanem G, Kenzo K, Meredith P, Pezzella A, Santato C, Sarna T, Simon JD, Zecca L, Zucca FA, Napolitano A, Ito S. Melanins and melanogenesis: from pigment cells to human health and technological applications. Pigment Cell Melanoma Res 2016; 28:520-44. [PMID: 26176788 DOI: 10.1111/pcmr.12393] [Citation(s) in RCA: 279] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 06/30/2015] [Indexed: 12/22/2022]
Abstract
During the past decade, melanins and melanogenesis have attracted growing interest for a broad range of biomedical and technological applications. The burst of polydopamine-based multifunctional coatings in materials science is just one example, and the list may be expanded to include melanin thin films for organic electronics and bioelectronics, drug delivery systems, functional nanoparticles and biointerfaces, sunscreens, environmental remediation devices. Despite considerable advances, applied research on melanins and melanogenesis is still far from being mature. A closer intersectoral interaction between research centers is essential to raise the interests and increase the awareness of the biomedical, biomaterials science and hi-tech sectors of the manifold opportunities offered by pigment cells and related metabolic pathways. Starting from a survey of biological roles and functions, the present review aims at providing an interdisciplinary perspective of melanin pigments and related pathway with a view to showing how it is possible to translate current knowledge about physical and chemical properties and control mechanisms into new bioinspired solutions for biomedical, dermocosmetic, and technological applications.
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Affiliation(s)
- Marco d'Ischia
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
| | - Fabio Cicoira
- Department of Chemical Engineering, École Polytechnique de Montréal, Montréal, QC, Canada
| | - Eduardo Di Mauro
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC, Canada
| | | | - Stephane Commo
- L'Oréal Recherche & Innovation, Aulnay sous Bois, France
| | - Ismael Galván
- Departamento de Ecología Evolutiva, Estación Biológica de Doñana - CSIC, Sevilla, Spain
| | - Ghanem Ghanem
- LOCE, Institut J. Bordet, Université Libre de Bruxelles, Brussels, Belgium
| | - Koike Kenzo
- Development Research - Hair Care Products, KAO Corporation, Sumida, Tokyo, Japan
| | - Paul Meredith
- Centre for Organic Photonics and Electronics, School of Mathematics and Physics, University of Queensland, Brisbane, Qld, Australia
| | - Alessandro Pezzella
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
| | - Clara Santato
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC, Canada
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - John D Simon
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Luigi Zecca
- Institute of Biomedical Technologies - National Research Council of Italy, Milan, Italy
| | - Fabio A Zucca
- Institute of Biomedical Technologies - National Research Council of Italy, Milan, Italy
| | | | - Shosuke Ito
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
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63
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"Fifty Shades" of Black and Red or How Carboxyl Groups Fine Tune Eumelanin and Pheomelanin Properties. Int J Mol Sci 2016; 17:ijms17050746. [PMID: 27196900 PMCID: PMC4881568 DOI: 10.3390/ijms17050746] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 05/02/2016] [Accepted: 05/05/2016] [Indexed: 01/09/2023] Open
Abstract
Recent advances in the chemistry of melanins have begun to disclose a number of important structure-property-function relationships of crucial relevance to the biological role of human pigments, including skin (photo) protection and UV-susceptibility. Even slight variations in the monomer composition of black eumelanins and red pheomelanins have been shown to determine significant differences in light absorption, antioxidant, paramagnetic and redox behavior, particle morphology, surface properties, metal chelation and resistance to photo-oxidative wear-and-tear. These variations are primarily governed by the extent of decarboxylation at critical branching points of the eumelanin and pheomelanin pathways, namely the rearrangement of dopachrome to 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA), and the rearrangement of 5-S-cysteinyldopa o-quinoneimine to 1,4-benzothiazine (BTZ) and its 3-carboxylic acid (BTZCA). In eumelanins, the DHICA-to-DHI ratio markedly affects the overall antioxidant and paramagnetic properties of the resulting pigments. In particular, a higher content in DHICA decreases visible light absorption and paramagnetic response relative to DHI-based melanins, but markedly enhances antioxidant properties. In pheomelanins, likewise, BTZCA-related units, prevalently formed in the presence of zinc ions, appear to confer pronounced visible and ultraviolet A (UVA) absorption features, accounting for light-dependent reactive oxygen species (ROS) production, whereas non-carboxylated benzothiazine intermediates seem to be more effective in inducing ROS production by redox cycling mechanisms in the dark. The possible biological and functional significance of carboxyl retention in the eumelanin and pheomelanin pathways is discussed.
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64
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Solano F. Photoprotectionversusphotodamage: updating an old but still unsolved controversy about melanin. POLYM INT 2016. [DOI: 10.1002/pi.5117] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- F Solano
- Department of Biochemistry and Molecular Biology B and Research Group for Molecular Control of Cell Proliferation, School of Medicine and IMIB; University of Murcia; 30100 Murcia Spain
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65
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Zhou J, Shi W, Li L, Gong Q, Wu X, Li X, Ma H. Detection of Misdistribution of Tyrosinase from Melanosomes to Lysosomes and Its Upregulation under Psoralen/Ultraviolet A with a Melanosome-Targeting Tyrosinase Fluorescent Probe. Anal Chem 2016; 88:4557-64. [DOI: 10.1021/acs.analchem.6b00742] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Jin Zhou
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Wen Shi
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Lihong Li
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Qiuyu Gong
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiaofeng Wu
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiaohua Li
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Huimin Ma
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Analytical Chemistry for
Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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66
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Tuna D, Udvarhelyi A, Sobolewski AL, Domcke W, Domratcheva T. Onset of the Electronic Absorption Spectra of Isolated and π-Stacked Oligomers of 5,6-Dihydroxyindole: An Ab Initio Study of the Building Blocks of Eumelanin. J Phys Chem B 2016; 120:3493-502. [PMID: 27005558 DOI: 10.1021/acs.jpcb.6b01793] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Eumelanin is a naturally occurring skin pigment which is responsible for developing a suntan. The complex structure of eumelanin consists of π-stacked oligomers of various indole derivatives, such as the monomeric building block 5,6-dihydroxyindole (DHI). In this work, we present an ab initio wave-function study of the absorption behavior of DHI oligomers and of doubly and triply π-stacked species of these oligomers. We have simulated the onset of the electronic absorption spectra by employing the MP2 and the linear-response CC2 methods. Our results demonstrate the effect of an increasing degree of oligomerization of DHI and of an increasing degree of π-stacking of DHI oligomers on the onset of the absorption spectra and on the degree of red-shift toward the visible region of the spectrum. We find that π-stacking of DHI and its oligomers substantially red-shifts the onset of the absorption spectra. Our results also suggest that the optical properties of biological eumelanin cannot be simulated by considering the DHI building blocks alone, but instead the building blocks indole-semiquinone and indole-quinone have to be considered as well. This study contributes to advancing the understanding of the complex photophysics of the eumelanin biopolymer.
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Affiliation(s)
- Deniz Tuna
- Department of Chemistry, Technische Universität München , 85747 Garching, Germany
| | - Anikó Udvarhelyi
- Department of Biomolecular Mechanisms, Max-Planck-Institut für Medizinische Forschung , 69120 Heidelberg, Germany
| | | | - Wolfgang Domcke
- Department of Chemistry, Technische Universität München , 85747 Garching, Germany
| | - Tatiana Domratcheva
- Department of Biomolecular Mechanisms, Max-Planck-Institut für Medizinische Forschung , 69120 Heidelberg, Germany
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67
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Barra M, Bonadies I, Carfagna C, Cassinese A, Cimino F, Crescenzi O, Criscuolo V, Marco D, Maglione MG, Manini P, Migliaccio L, Musto A, Napolitano A, Navarra A, Panzella L, Parisi S, Pezzella A, Prontera CT, Tassini P. Eumelanin-Based Organic Bioelectronics: Myth or Reality? ACTA ACUST UNITED AC 2015. [DOI: 10.1557/adv.2015.49] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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68
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Kim E, Panzella L, Micillo R, Bentley WE, Napolitano A, Payne GF. Reverse Engineering Applied to Red Human Hair Pheomelanin Reveals Redox-Buffering as a Pro-Oxidant Mechanism. Sci Rep 2015; 5:18447. [PMID: 26669666 PMCID: PMC4680885 DOI: 10.1038/srep18447] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 11/18/2015] [Indexed: 12/23/2022] Open
Abstract
Pheomelanin has been implicated in the increased susceptibility to UV-induced melanoma for people with light skin and red hair. Recent studies identified a UV-independent pathway to melanoma carcinogenesis and implicated pheomelanin's pro-oxidant properties that act through the generation of reactive oxygen species and/or the depletion of cellular antioxidants. Here, we applied an electrochemically-based reverse engineering methodology to compare the redox properties of human hair pheomelanin with model synthetic pigments and natural eumelanin. This methodology exposes the insoluble melanin samples to complex potential (voltage) inputs and measures output response characteristics to assess redox activities. The results demonstrate that both eumelanin and pheomelanin are redox-active, they can rapidly (sec-min) and repeatedly redox-cycle between oxidized and reduced states, and pheomelanin possesses a more oxidative redox potential. This study suggests that pheomelanin's redox-based pro-oxidant activity may contribute to sustaining a chronic oxidative stress condition through a redox-buffering mechanism.
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Affiliation(s)
- Eunkyoung Kim
- Institute for Biosystems and Biotechnology Research University of Maryland 5115 Plant Sciences Building College Park, MD 20742, USA
- Fischell Department of Bioengineering University of Maryland College Park, MD 20742, USA
| | - Lucia Panzella
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Naples (Italy)
| | - Raffaella Micillo
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Naples (Italy)
- Department of Clinical Medicine and Surgery, University of Naples “Federico II” – Via Pansini 5, I-80131 Naples, Italy
| | - William E. Bentley
- Institute for Biosystems and Biotechnology Research University of Maryland 5115 Plant Sciences Building College Park, MD 20742, USA
- Fischell Department of Bioengineering University of Maryland College Park, MD 20742, USA
| | - Alessandra Napolitano
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Naples (Italy)
| | - Gregory F. Payne
- Institute for Biosystems and Biotechnology Research University of Maryland 5115 Plant Sciences Building College Park, MD 20742, USA
- Fischell Department of Bioengineering University of Maryland College Park, MD 20742, USA
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69
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Hirobe T, Ito S, Wakamatsu K. The slaty (slt/Dct(slt) ) allele decreases the content of eumelanin, but not pheomelanin in the mouse hair. Pigment Cell Melanoma Res 2015; 29:110-2. [PMID: 26451690 DOI: 10.1111/pcmr.12427] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tomohisa Hirobe
- Fukushima Project Headquarters, National Institute of Radiological Sciences, Chiba, Japan
| | - Shosuke Ito
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Japan
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Japan
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70
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Xiao M, Li Y, Allen MC, Deheyn DD, Yue X, Zhao J, Gianneschi NC, Shawkey MD, Dhinojwala A. Bio-Inspired Structural Colors Produced via Self-Assembly of Synthetic Melanin Nanoparticles. ACS NANO 2015; 9:5454-60. [PMID: 25938924 DOI: 10.1021/acsnano.5b01298] [Citation(s) in RCA: 161] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Structural colors arising from interactions of light with submicron scale periodic structures have been found in many species across all taxa, serving multiple biological functions including sexual signaling, camouflage, and aposematism. Directly inspired by the extensive use of self-assembled melanosomes to produce colors in avian feathers, we set out to synthesize and assemble polydopamine-based synthetic melanin nanoparticles in an effort to fabricate colored films. We have quantitatively demonstrated that synthetic melanin nanoparticles have a high refractive index and broad absorption spanning across the UV-visible range, similar to natural melanins. Utilizing a thin-film interference model, we demonstrated the coloration mechanism of deposited films and showed that the unique optical properties of synthetic melanin nanoparticles provide advantages for structural colors over other polymeric nanoparticles (i.e., polystyrene colloidal particles).
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Affiliation(s)
- Ming Xiao
- †Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | | | - Michael C Allen
- §Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States
| | - Dimitri D Deheyn
- §Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States
| | | | - Jiuzhou Zhao
- †Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | | | - Matthew D Shawkey
- ∥Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, Ohio 44325, United States
| | - Ali Dhinojwala
- †Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
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71
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Vitiello G, Pezzella A, Zanfardino A, Varcamonti M, Silvestri B, Costantini A, Branda F, Luciani G. Titania as a driving agent for DHICA polymerization: a novel strategy for the design of bioinspired antimicrobial nanomaterials. J Mater Chem B 2015; 3:2808-2815. [DOI: 10.1039/c5tb00039d] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Organic materials are widely employed to tune surface chemistry and/or as structuring agents of inorganic materials.
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Affiliation(s)
- Giuseppe Vitiello
- Dipartimento di Ingegneria Chimica
- dei Materiali e della Produzione Industriale
- Università di Napoli “Federico II”
- 80125 Napoli
- Italy
| | - Alessandro Pezzella
- Dipartimento di Scienze Chimiche
- Università di Napoli “Federico II” via Cintia 4
- 80126 Napoli
- Italy
| | - Anna Zanfardino
- Dipartimento di Biologia
- Università di Napoli “Federico II” via Cintia 4
- 80126 Napoli
- Italy
| | - Mario Varcamonti
- Dipartimento di Biologia
- Università di Napoli “Federico II” via Cintia 4
- 80126 Napoli
- Italy
| | - Brigida Silvestri
- Dipartimento di Ingegneria Chimica
- dei Materiali e della Produzione Industriale
- Università di Napoli “Federico II”
- 80125 Napoli
- Italy
| | - Aniello Costantini
- Dipartimento di Ingegneria Chimica
- dei Materiali e della Produzione Industriale
- Università di Napoli “Federico II”
- 80125 Napoli
- Italy
| | - Francesco Branda
- Dipartimento di Ingegneria Chimica
- dei Materiali e della Produzione Industriale
- Università di Napoli “Federico II”
- 80125 Napoli
- Italy
| | - Giuseppina Luciani
- Dipartimento di Ingegneria Chimica
- dei Materiali e della Produzione Industriale
- Università di Napoli “Federico II”
- 80125 Napoli
- Italy
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72
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Zhang H, Yang T, Wu X, Zhou Y, Yang C, Zhu T, Dong R. Using Li+ as the electrochemical messenger to fabricate an aqueous rechargeable Zn–Cu battery. Chem Commun (Camb) 2015; 51:7294-7. [DOI: 10.1039/c5cc00575b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Li+ ions driven by the electrochemical potential in an aqueous Zn–Cu rechargeable battery could be called the electrochemical messenger.
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Affiliation(s)
- Hanping Zhang
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Tao Yang
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Xin Wu
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Yisen Zhou
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Chao Yang
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Tian Zhu
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
| | - Rulin Dong
- Jiangsu Key Laboratory of Advanced Catalytic materials and technology
- Changzhou University
- Changzhou
- China
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73
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Prampolini G, Cacelli I, Ferretti A. Intermolecular interactions in eumelanins: a computational bottom-up approach. I. small building blocks. RSC Adv 2015. [DOI: 10.1039/c5ra03773e] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Building eumelanin: from basic units to spectral properties.
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Affiliation(s)
- Giacomo Prampolini
- Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR)
- Area della Ricerca
- I-56124 Pisa
- Italy
| | - Ivo Cacelli
- Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR)
- Area della Ricerca
- I-56124 Pisa
- Italy
- Dipartimento di Chimica e Chimica Industriale
| | - Alessandro Ferretti
- Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR)
- Area della Ricerca
- I-56124 Pisa
- Italy
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74
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Pinna A, Simbula F, Marongiu D, Pezzella A, d'Ischia M, Mula G. Boosting, probing and switching-off visible light-induced photocurrents in eumelanin-porous silicon hybrids. RSC Adv 2015. [DOI: 10.1039/c5ra08605a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Improved solid state polymerization of eumelanin in porous silicon and new insights into the mechanisms of photoconduction of eumelanin films.
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Affiliation(s)
- Andrea Pinna
- Dipartimento di Fisica
- Università degli Studi di Cagliari
- Italy
| | | | | | - Alessandro Pezzella
- Dipartimento di Scienze Chimiche
- Università di Napoli “Federico II”
- I-80126 Napoli
- Italy
- Institute for Polymers
| | - Marco d'Ischia
- Dipartimento di Scienze Chimiche
- Università di Napoli “Federico II”
- I-80126 Napoli
- Italy
| | - Guido Mula
- Dipartimento di Fisica
- Università degli Studi di Cagliari
- Italy
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75
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Selvaraju S, Niradha Sachinthani KA, Hopson RA, McFarland FM, Guo S, Rheingold AL, Nelson TL. Eumelanin-inspired core derived from vanillin: a new building block for organic semiconductors. Chem Commun (Camb) 2015; 51:2957-9. [DOI: 10.1039/c4cc09011j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An eumelanin-inspired core derived from the natural product, vanillin (vanilla bean extract) was utilized for the synthesis of eumelanin-inspired small molecules and polymer via Sonogashira cross coupling.
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Affiliation(s)
| | | | | | - Frederick M. McFarland
- Department of Chemistry and Biochemistry
- The University of Southern Mississippi
- Hattiesburg
- USA
| | - Song Guo
- Department of Chemistry and Biochemistry
- The University of Southern Mississippi
- Hattiesburg
- USA
| | | | - Toby L. Nelson
- Department of Chemistry
- Oklahoma State University
- Stillwater
- USA
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