1
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Motovilov KA, Mostert AB. Melanin: Nature's 4th bioorganic polymer. SOFT MATTER 2024; 20:5635-5651. [PMID: 39012013 DOI: 10.1039/d4sm00491d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
The pigments known as the melanins are widely recognized for their responsibility in the coloration of human skin, eyes, hair, and minimising the harmful effects of solar ultraviolet radiation. But specialists are aware that the melanins are present in all living kingdoms, barring viruses, and have functionality that extends beyond neutralizing ionising radiation. The ubiquitous presence of melanin in almost all human organs, recognized in recent years, as well as the presence of melanin in organisms that are evolutionarily distant from each other, indicate the fundamental importance of this class of material for all life forms. In this review, we argue for the need to accept melanins as the fourth primordial class of biological polymers, along with nucleic acids, proteins and polysaccharides. We consistently compare the properties of these canonical biological polymers with the properties of melanin and highlight key features that fundamentally distinguish melanins, their function and its mysteries.
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Affiliation(s)
- K A Motovilov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institutsky Lane 9, Dolgoprudny 141701, Moscow Region, Russia.
| | - A B Mostert
- Department of Physics and Centre for Integrative Semiconductor Materials, Swansea University Bay Campus, Fabian Way, Swansea SA1 8EN, UK
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2
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Menichetti A, Mordini D, Vicenzi S, Montalti M. Melanin for Photoprotection and Hair Coloration in the Emerging Era of Nanocosmetics. Int J Mol Sci 2024; 25:5862. [PMID: 38892049 PMCID: PMC11172709 DOI: 10.3390/ijms25115862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/23/2024] [Accepted: 05/25/2024] [Indexed: 06/21/2024] Open
Abstract
Nanotechnology is revolutionizing fields of high social and economic impact. such as human health preservation, energy conversion and storage, environmental decontamination, and art restoration. However, the possible global-scale application of nanomaterials is raising increasing concerns, mostly related to the possible toxicity of materials at the nanoscale. The possibility of using nanomaterials in cosmetics, and hence in products aimed to be applied directly to the human body, even just externally, is strongly debated. Preoccupation arises especially from the consideration that nanomaterials are mostly of synthetic origin, and hence are often seen as "artificial" and their effects as unpredictable. Melanin, in this framework, is a unique material since in nature it plays important roles that specific cosmetics are aimed to cover, such as photoprotection and hair and skin coloration. Moreover, melanin is mostly present in nature in the form of nanoparticles, as is clearly observable in the ink of some animals, like cuttlefish. Moreover, artificial melanin nanoparticles share the same high biocompatibility of the natural ones and the same unique chemical and photochemical properties. Melanin is hence a natural nanocosmetic agent, but its actual application in cosmetics is still under development, also because of regulatory issues. Here, we critically discuss the most recent examples of the application of natural and biomimetic melanin to cosmetics and highlight the requirements and future steps that would improve melanin-based cosmetics in the view of future applications in the everyday market.
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Affiliation(s)
- Arianna Menichetti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.); (D.M.); (S.V.)
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Tecnopolo di Rimini, Via Dario Campana 71, 47921 Rimini, Italy
| | - Dario Mordini
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.); (D.M.); (S.V.)
| | - Silvia Vicenzi
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.); (D.M.); (S.V.)
| | - Marco Montalti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.); (D.M.); (S.V.)
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Tecnopolo di Rimini, Via Dario Campana 71, 47921 Rimini, Italy
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3
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Petropoulos V, Mavridi-Printezi A, Menichetti A, Mordini D, Kabacinski P, Gianneschi NC, Montalti M, Maiuri M, Cerullo G. Sub-50 fs Formation of Charge Transfer States Rules the Fate of Photoexcitations in Eumelanin-Like Materials. J Phys Chem Lett 2024; 15:3639-3645. [PMID: 38530860 DOI: 10.1021/acs.jpclett.4c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Eumelanins play a crucial role as photoprotective agents for living organisms, yet the nature of the stationary and transient species involved in the light absorption and deactivation processes remains controversial. Moreover, the critical sub-100 fs time scale, which is key to the characterization of the primary excited species, has remained unexplored. Here, we study the eumelanin analogue polydopamine (PDA) and employ a combination of steady-state and transient optical spectroscopies to reveal the presence of spectrally broad coupled electronic transitions with, at least partial, charge-transfer (CT) character. We monitor the CT state dynamics using tunable sub-20 fs pulses. We find that high photon energy excitation results in accelerated (sub-20 fs) CT formation times while activating pathways, which lead to long-lived (≫1 ns), possibly reactive CT species. On the other hand, visible light excitation results in a slower (≈45 fs) formation of bound CT states, which, however, recombine on the ultrafast sub-2 ps time scale.
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Affiliation(s)
- Vasilis Petropoulos
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | | | - Arianna Menichetti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Dario Mordini
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Piotr Kabacinski
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Nathan C Gianneschi
- Departments of Chemistry, Materials Science & Engineering, Biomedical Engineering and Pharmacology, Northwestern University, Evanston, Illinois 60208, United States
- Department of Chemistry & Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Marco Montalti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Margherita Maiuri
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Istituto di Fotonica e Nanotecnologie (IFN)-Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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4
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Choudhury A, Ramakrishnan R, Ghosh D. Structure prediction from spectra amidst dynamical heterogeneity in melanin. Chem Commun (Camb) 2024; 60:2613-2616. [PMID: 38265468 DOI: 10.1039/d3cc06137j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Melanin is a biopolymer pigment that plays a central role in skin photoprotection. Its extensive chemical and dynamical heterogeneity imparts this property through a broad featureless ultraviolet/visible absorption spectrum. Conventionally, the rational design of synthetic photoprotective pigments revolves around establishing the structure-spectra correlation and developing biomimetic materials with desired optical properties. This approach fails to explain the mechanistic details of melanin's absorption spectrum because it arises from an ensemble of structures rather than a local minimum on the potential energy surface. Here, we propose an inverse design approach to elucidate the contributions of dominant chromophoric units in various wavelength domains of the melanin spectrum.
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Affiliation(s)
- Arpan Choudhury
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.
| | | | - Debashree Ghosh
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.
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5
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Cardia R, Dardenne N, Mula G, Pinna E, Rignanese GM, Charlier JC, Cappellini G. First-Principles Investigation of the Optical Properties of Eumelanin Protomolecules. J Phys Chem A 2023; 127:10797-10806. [PMID: 38109190 DOI: 10.1021/acs.jpca.3c04898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Using first-principles calculations, we investigate the absorption spectra (in the near-infrared, visible, and first UV range) of the two most probable eumelanin tetrameric molecules exhibiting either a linear open-chain or a cyclic porphyrine-like configuration. In order to simulate a realistic molecular system, an implicit solvent model is used in our calculations to mimic the effect of the solvated environment around the eumelanin molecule. Although the presence of solvent is found not to significantly affect the absorption pattern of both molecules, the onset of the spectra are shifted toward higher energies, especially for the linear tetramer. Interestingly, the absorption spectra and optical onsets of the two molecules differ significantly both in a vacuum and in ethanol. However, the two predicted spectra do not allow us to definitely discriminate between the two configurations when comparing the theoretical predictions with the available experimental spectrum. In addition, a mix of the two eumelanin configurations (close to fifty-fifty) leads to a maximum overlap between theoretical and experimental spectra. Consequently, this theoretical research shows that deeper insight can be gained using beyond DFT techniques on the real form of eumelanin protomolecules present in living systems as well as on their possible use in hybrid solar cells.
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Affiliation(s)
- Roberto Cardia
- Department of Physics, Università degli Studi di Cagliari, Cittadella Universitaria I-09042 Monserrato, Cagliari, Italy
| | - Nicolas Dardenne
- Institute of Condensed Matter and Nanosciences, Université catholique de Louvain (UCLouvain), B-1348 Louvain-la-Neuve, Belgium
| | - Guido Mula
- Department of Physics, Università degli Studi di Cagliari, Cittadella Universitaria I-09042 Monserrato, Cagliari, Italy
| | - Elisa Pinna
- Department of Physics, Università degli Studi di Cagliari, Cittadella Universitaria I-09042 Monserrato, Cagliari, Italy
| | - Gian-Marco Rignanese
- Institute of Condensed Matter and Nanosciences, Université catholique de Louvain (UCLouvain), B-1348 Louvain-la-Neuve, Belgium
- European Theoretical Spectroscopy Facility (ETSF)
| | - Jean-Christophe Charlier
- Institute of Condensed Matter and Nanosciences, Université catholique de Louvain (UCLouvain), B-1348 Louvain-la-Neuve, Belgium
- European Theoretical Spectroscopy Facility (ETSF)
| | - Giancarlo Cappellini
- Department of Physics, Università degli Studi di Cagliari, Cittadella Universitaria I-09042 Monserrato, Cagliari, Italy
- European Theoretical Spectroscopy Facility (ETSF)
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6
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Mavridi-Printezi A, Giordani S, Menichetti A, Mordini D, Zattoni A, Roda B, Ferrazzano L, Reschiglian P, Marassi V, Montalti M. The dual nature of biomimetic melanin. NANOSCALE 2023; 16:299-308. [PMID: 38059484 DOI: 10.1039/d3nr04696f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Melanin-inspired nanomaterials offer unique photophysical, electronic and radical scavenging properties that are widely explored for health and environmental preservation, or energy conversion and storage. The incorporation of functional melanin building blocks in more complex nanostructures or surfaces is typically achieved via a bottom-up approach starting from a molecular precursor, in most cases dopamine. Here we demonstrate that indeed, the oxidative polymerization of dopamine, for the synthesis of melanin-like polydopamine (PDA), leads to the simultaneous formation of more than one nanosized species with different compositions, morphologies and properties. In particular, a low-density polymeric structure and dense nanoparticles (NP) are simultaneously formed. The two populations could be separated and analyzed in real time using a chromatographic technique free of any stationary phase (flow field fractionation, FFF). The results following the synthesis of melanin-like PDA showed that the NP are formed only during the first 6 hours as a result of a supramolecular self-assembly-driven polymerization, while the formation of the polymer continues for about 36 hours. The two populations were also separated and characterized using TEM, UV-vis absorption spectroscopy, fluorescence and light scattering spectroscopy, DLS, FTIR, ζ-potential measurements, gel electrophoresis and pH titrations. Interestingly, very different properties between the two populations were observed: in particular the polymer contains a higher number of catechol units (8 mmol g-1 -OH) with respect to the NP (1 mmol g-1 -OH) and presents a much higher antioxidant activity. The attenuation of light by NP is more efficient than that by the polymer especially in the Vis-NIR region. Moreover, while the NP scatter light with an efficiency up to 27% they are not fluorescent, and the polymer does not scatter light but shows an excitation wavelength-dependent fluorescence typical of multi-fluorophoric uncoupled systems.
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Affiliation(s)
| | - Stefano Giordani
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | - Arianna Menichetti
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
- Tecnopolo di Rimini, Via Dario Campana, 71, 47922 Rimini, Italy
| | - Dario Mordini
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | - Andrea Zattoni
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | - Barbara Roda
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | - Lucia Ferrazzano
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | | | - Valentina Marassi
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
| | - Marco Montalti
- Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126 Bologna, Italy.
- Tecnopolo di Rimini, Via Dario Campana, 71, 47922 Rimini, Italy
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7
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Abstract
Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.
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Affiliation(s)
- Erick L Bastos
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
| | - Frank H Quina
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
- Department of Chemical Engineering, Polytechnic School, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
| | - Maurício S Baptista
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
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8
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Mavridi-Printezi A, Menichetti A, Mordini D, Montalti M. Functionalization of and through Melanin: Strategies and Bio-Applications. Int J Mol Sci 2023; 24:9689. [PMID: 37298641 PMCID: PMC10253489 DOI: 10.3390/ijms24119689] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/25/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
A unique feature of nanoparticles for bio-application is the ease of achieving multi-functionality through covalent and non-covalent functionalization. In this way, multiple therapeutic actions, including chemical, photothermal and photodynamic activity, can be combined with different bio-imaging modalities, such as magnetic resonance, photoacoustic, and fluorescence imaging, in a theragnostic approach. In this context, melanin-related nanomaterials possess unique features since they are intrinsically biocompatible and, due to their optical and electronic properties, are themselves very efficient photothermal agents, efficient antioxidants, and photoacoustic contrast agents. Moreover, these materials present a unique versatility of functionalization, which makes them ideal for the design of multifunctional platforms for nanomedicine integrating new functions such as drug delivery and controlled release, gene therapy, or contrast ability in magnetic resonance and fluorescence imaging. In this review, the most relevant and recent examples of melanin-based multi-functionalized nanosystems are discussed, highlighting the different methods of functionalization and, in particular, distinguishing pre-functionalization and post-functionalization. In the meantime, the properties of melanin coatings employable for the functionalization of a variety of material substrates are also briefly introduced, especially in order to explain the origin of the versatility of melanin functionalization. In the final part, the most relevant critical issues related to melanin functionalization that may arise during the design of multifunctional melanin-like nanoplatforms for nanomedicine and bio-application are listed and discussed.
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Affiliation(s)
| | | | | | - Marco Montalti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.-P.); (A.M.); (D.M.)
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9
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González Moreno A, Woolley JM, Domínguez E, de Cózar A, Heredia A, Stavros VG. Synergic photoprotection of phenolic compounds present in tomato fruit cuticle: a spectroscopic investigation in solution. Phys Chem Chem Phys 2023; 25:12791-12799. [PMID: 37129056 DOI: 10.1039/d3cp00630a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Coumaric acids and flavonoids play pivotal roles in protecting plants against ultraviolet radiation (UVR) exposure. In this work, we focus our photoprotection studies on p-coumaric acid and the flavonoid naringenin chalcone. Photoprotection is well-understood in p-coumaric acid; in contrast, information surrounding photoprotection in naringenin chalcone is lacking. Additionally, and vitally, how these two species work in unison to provide photoprotection across the UV-B and UV-A is unknown. Herein, we employ transient absorption spectroscopy together with steady-state irradiation studies to unravel the photoprotection mechanism of a solution of p-coumaric acid and naringenin chalcone. We find that the excited state dynamics of p-coumaric acid are significantly altered in the presence of naringenin chalcone. This finding concurs with quenching of the p-coumaric acid fluorescence with increasing concentration of naringenin chalcone. We propose a Förster energy transfer mechanism is operative via the formation of dipole-dipole interactions between p-coumaric acid and naringenin chalcone. To our knowledge, this is the first demonstration in plants of a synergic effect between two classes of phenolics to bypass the potentially damaging effects of UVR.
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Affiliation(s)
- Ana González Moreno
- IHSM-UMA-CSIC La Mayora, Departamento de Biología Molecular y Bioquímica, Universidad de Málaga (UMA), 29071, Málaga, Spain.
| | - Jack M Woolley
- Department of Chemistry, University of Warwick, Coventry, UK.
| | - Eva Domínguez
- IHSM-UMA-CSIC La Mayora, Plant breeding and Biotechnology, CSIC, 29750 Algarrobo-Costa, Málaga, Spain
| | - Abel de Cózar
- Departamento de Química Orgánica I/Kimika Organikoa I Saila, Facultad de Química/Kimika Fakultatea, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P. K, 1072, 20018 San Sebastián - Donostia, Spain
- Ikerbasque, Basque Foundation for Science, Plaza Euskadi 5, 48009, Bilbao, Spain
| | - Antonio Heredia
- IHSM-UMA-CSIC La Mayora, Departamento de Biología Molecular y Bioquímica, Universidad de Málaga (UMA), 29071, Málaga, Spain.
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10
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Terranova ML. Prominent Roles and Conflicted Attitudes of Eumelanin in the Living World. Int J Mol Sci 2023; 24:ijms24097783. [PMID: 37175490 PMCID: PMC10178024 DOI: 10.3390/ijms24097783] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/17/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023] Open
Abstract
Eumelanin, a macromolecule widespread in all the living world and long appreciated for its protective action against harmful UV radiation, is considered the beneficial component of the melanin family (ευ means good in ancient Greek). This initially limited picture has been rather recently extended and now includes a variety of key functions performed by eumelanin in order to support life also under extreme conditions. A lot of still unexplained aspects characterize this molecule that, in an evolutionary context, survived natural selection. This paper aims to emphasize the unique characteristics and the consequent unusual behaviors of a molecule that still holds the main chemical/physical features detected in fossils dating to the late Carboniferous. In this context, attention is drawn to the duality of roles played by eumelanin, which occasionally reverses its functional processes, switching from an anti-oxidant to a pro-oxidant behavior and implementing therefore harmful effects.
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Affiliation(s)
- Maria Letizia Terranova
- Dipartimento Scienze e Tecnologie Chimiche, Università degli Studi di Roma "Tor Vergata", Via della Ricerca Scientifica, 00133 Roma, Italy
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11
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Wei YC, Chen BH, Ye RS, Huang HW, Su JX, Lin CY, Hodgkiss J, Hsu LY, Chi Y, Chen K, Lu CH, Yang SD, Chou PT. Excited-State THz Vibrations in Aggregates of Pt II Complexes Contribute to the Enhancement of Near-Infrared Emission Efficiencies. Angew Chem Int Ed Engl 2023; 62:e202300815. [PMID: 36825300 DOI: 10.1002/anie.202300815] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/23/2023] [Accepted: 02/23/2023] [Indexed: 02/25/2023]
Abstract
The exploration of deactivation mechanisms for near-infrared(NIR)-emissive organic molecules has been a key issue in chemistry, materials science and molecular biology. In this study, based on transient absorption spectroscopy and transient grating photoluminescence spectroscopy, we demonstrate that the aggregated PtII complex 4H (efficient NIR emitter) exhibits collective out-of-plane motions with a frequency of 32 cm-1 (0.96 THz) in the excited states. Importantly, similar THz characteristics were also observed in analogous PtII complexes with prominent NIR emission efficiency. The conservation of THz motions enables excited-state deactivation to proceed along low-frequency vibrational coordinates, contributing to the suppression of nonradiative decay and remarkable NIR emission. These novel results highlight the significance of excited-state vibrations in nonradiative processes, which serve as a benchmark for improving device performance.
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Affiliation(s)
- Yu-Chen Wei
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Bo-Han Chen
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Ren-Siang Ye
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Hsing-Wei Huang
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Jia-Xuan Su
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Chao-Yang Lin
- Robinson Research Institute, Faculty of Engineering, Victoria University of Wellington, Wellington, 6012, New Zealand
| | - Justin Hodgkiss
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, 6010, New Zealand
| | - Lian-Yan Hsu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- National Center for Theoretical Sciences, Taipei, 10617, Taiwan
| | - Yun Chi
- Department of Materials Science and Engineering, Department of Chemistry, and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong SAR, Hong Kong
| | - Kai Chen
- Robinson Research Institute, Faculty of Engineering, Victoria University of Wellington, Wellington, 6012, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, 6010, New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Dunedin, 9016, New Zealand
| | - Chih-Hsuan Lu
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Shang-Da Yang
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
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12
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Gonçalves LCP, Angelé-Martinez C, Premi S, Palmatier MA, Prado FM, Di Mascio P, Bastos EL, Brash DE. Chemiexcited Neurotransmitters and Hormones Create DNA Photoproducts in the Dark. ACS Chem Biol 2023; 18:484-493. [PMID: 36775999 PMCID: PMC10276651 DOI: 10.1021/acschembio.2c00787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
In DNA, electron excitation allows adjacent pyrimidine bases to dimerize by [2 + 2] cycloaddition, creating chemically stable but lethal and mutagenic cyclobutane pyrimidine dimers (CPDs). The usual cause is ultraviolet radiation. Alternatively, CPDs can be made in the dark (dCPDs) via chemically mediated electron excitation of the skin pigment melanin, after it is oxidized by peroxynitrite formed from the stress-induced radicals superoxide and nitric oxide. We now show that the dark process is not limited to the unusual structural molecule melanin: signaling biomolecules such as indolamine and catecholamine neurotransmitters and hormones can also be chemiexcited to energy levels high enough to form dCPDs. Oxidation of serotonin, dopamine, melatonin, and related biogenic amines by peroxynitrite created triplet-excited species, evidenced by chemiluminescence, energy transfer to a triplet-state reporter, or transfer to O2 resulting in singlet molecular oxygen. For a subset of these signaling molecules, triplet states created by peroxynitrite or peroxidase generated dCPDs at levels comparable to ultraviolet (UV). Neurotransmitter catabolism by monoamine oxidase also generated dCPDs. These results reveal a large class of signaling molecules as electronically excitable by biochemical reactions and thus potential players in deviant mammalian metabolism in the absence of light.
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Affiliation(s)
- Leticia C. P. Gonçalves
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
- Present address: Institut de Chimie de Nice CNRS UMR7272, Université Côte d’Azur, 28 Avenue Valrose 06108 Nice, France
| | - Carlos Angelé-Martinez
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Sanjay Premi
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
- Present address: Department of Tumor Biology, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Meg A. Palmatier
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Fernanda Manso Prado
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Erick L. Bastos
- Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, 05508-000 São Paulo, SP, Brazil
| | - Douglas E. Brash
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
- Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, 06520-8028, USA
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13
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Wei Y, Chen B, Ye R, Huang H, Su J, Lin C, Hodgkiss J, Hsu L, Chi Y, Chen K, Lu C, Yang S, Chou P. Excited‐State THz Vibrations in Aggregates of Pt
II
Complexes Contribute to the Enhancement of Near‐Infrared Emission Efficiencies**. Angew Chem Int Ed Engl 2023. [DOI: 10.1002/ange.202300815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Affiliation(s)
- Yu‐Chen Wei
- Department of Chemistry National Taiwan University Taipei 10617 Taiwan
- Institute of Atomic and Molecular Sciences Academia Sinica Taipei 10617 Taiwan
| | - Bo‐Han Chen
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Ren‐Siang Ye
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Hsing‐Wei Huang
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Jia‐Xuan Su
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Chao‐Yang Lin
- Robinson Research Institute Faculty of Engineering Victoria University of Wellington Wellington 6012 New Zealand
| | - Justin Hodgkiss
- MacDiarmid Institute for Advanced Materials and Nanotechnology Wellington 6010 New Zealand
| | - Lian‐Yan Hsu
- Department of Chemistry National Taiwan University Taipei 10617 Taiwan
- Institute of Atomic and Molecular Sciences Academia Sinica Taipei 10617 Taiwan
- National Center for Theoretical Sciences Taipei 10617 Taiwan
| | - Yun Chi
- Department of Materials Science and Engineering Department of Chemistry and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR Hong Kong
| | - Kai Chen
- Robinson Research Institute Faculty of Engineering Victoria University of Wellington Wellington 6012 New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology Wellington 6010 New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies Dunedin 9016 New Zealand
| | - Chih‐Hsuan Lu
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Shang‐Da Yang
- Institute of Photonics Technologies National Tsing Hua University Hsinchu 30013 Taiwan
| | - Pi‐Tai Chou
- Department of Chemistry National Taiwan University Taipei 10617 Taiwan
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14
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Characterization of Spontaneous Melanization by Fluorescence Spectroscopy: A Basis for Analytical Application to Biological Substrates. BIOLOGY 2023; 12:biology12030433. [PMID: 36979125 PMCID: PMC10044826 DOI: 10.3390/biology12030433] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023]
Abstract
Melanin is present in various biological substrates where it may participate in several processes, from innate immunity to the still-unsolved opposite roles in antioxidant protection, including photoprotection and the related ability to interact with light. Melanin–light interaction has also been an important source of inspiration for the development of innovative bioengineering applications. These are based on melanin’s light-energy-absorption ability of its chemically and structurally complex components and precursors, and on the improvement in analytical and diagnostic procedures in biomedicine. In this regard, here, we characterized the fluorescence spectral properties of melanin and of its precursor L-tyrosine in an aqueous solution during spontaneous melanization. Besides the confirmation of the typical fluorescence-emission signature of melanin and L-tyrosine, we provide additional insights on both emission and excitation spectra recorded during melanization. On these bases, we performed a subsequent characterization on the aqueous extracts from two different melanin-containing biological substrates, namely hairs from a domestic black cat and eggs from the Asian tiger mosquito. The results from the mild extraction procedure, purposely applied to obtain only the soluble components, combined with fluorescence spectral analysis are expected to promote further investigation of the melanization processes, particularly in insects.
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15
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Brash DE, Goncalves LCP. Chemiexcitation: Mammalian Photochemistry in the Dark †. Photochem Photobiol 2023; 99:251-276. [PMID: 36681894 PMCID: PMC10065968 DOI: 10.1111/php.13781] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 01/18/2023] [Indexed: 01/23/2023]
Abstract
Light is one way to excite an electron in biology. Another is chemiexcitation, birthing a reaction product in an electronically excited state rather than exciting from the ground state. Chemiexcited molecules, as in bioluminescence, can release more energy than ATP. Excited states also allow bond rearrangements forbidden in ground states. Molecules with low-lying unoccupied orbitals, abundant in biology, are particularly susceptible. In mammals, chemiexcitation was discovered to transfer energy from excited melanin, neurotransmitters, or hormones to DNA, creating the lethal and carcinogenic cyclobutane pyrimidine dimer. That process was initiated by nitric oxide and superoxide, radicals triggered by ultraviolet light or inflammation. Several poorly understood chronic diseases share two properties: inflammation generates those radicals across the tissue, and cells that die are those containing melanin or neuromelanin. Chemiexcitation may therefore be a pathogenic event in noise- and drug-induced deafness, Parkinson's disease, and Alzheimer's; it may prevent macular degeneration early in life but turn pathogenic later. Beneficial evolutionary selection for excitable biomolecules may thus have conferred an Achilles heel. This review of recent findings on chemiexcitation in mammalian cells also describes the underlying physics, biochemistry, and potential pathogenesis, with the goal of making this interdisciplinary phenomenon accessible to researchers within each field.
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Affiliation(s)
- Douglas E. Brash
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520-8040, USA
- Yale Cancer Center, Yale School of Medicine, New Haven, CT 06520-8028, USA
| | - Leticia C. P. Goncalves
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520-8040, USA
- Institut de Chimie de Nice CNRS UMR7272, Université Côte d’Azur, 28 Avenue Valrose 06108 Nice, France
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16
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Okada T, Iwayama T, Ogura T, Murakami S, Ogura T. Structural analysis of melanosomes in living mammalian cells using scanning electron-assisted dielectric microscopy with deep neural network. Comput Struct Biotechnol J 2022; 21:506-518. [PMID: 36618988 PMCID: PMC9807747 DOI: 10.1016/j.csbj.2022.12.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
Melanins are the main pigments found in mammals. Their synthesis and transfer to keratinocytes have been widely investigated for many years. However, analysis has been mainly carried out using fixed rather than live cells. In this study, we have analysed the melanosomes in living mammalian cells using newly developed scanning electron-assisted dielectric microscopy (SE-ADM). The melanosomes in human melanoma MNT-1 cells were observed as clear black particles in SE-ADM. The main structure of melanosomes was toroidal while that of normal melanocytes was ellipsoidal. In tyrosinase knockout MNT-1 cells, not only the black particles in the SE-ADM images but also the Raman shift of melanin peaks completely disappeared suggesting that the black particles were really melanosomes. We developed a deep neural network (DNN) system to automatically detect melanosomes in cells and analysed their diameter and roundness. In terms of melanosome morphology, the diameter of melanosomes in melanoma cells did not change while that in normal melanocytes increased during culture. The established DNN analysis system with SE-ADM can be used for other particles, e.g. exosomes, lysosomes, and other biological particles.
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Affiliation(s)
- Tomoko Okada
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi, Tsukuba, Ibaraki 305-8566, Japan
| | - Tomoaki Iwayama
- Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Taku Ogura
- Chemical Business Unit, Nikko Chemicals Co., Ltd., Itabashi-ku, Tokyo 174-0046, Japan
| | - Shinya Murakami
- Department of Periodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Toshihiko Ogura
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi, Tsukuba, Ibaraki 305-8566, Japan,Correspondence to: Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan.
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17
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Sarna T. Photodynamics of Melanin Radicals: Contribution to Photoprotection by Melanin †. Photochem Photobiol 2022; 99:866-868. [PMID: 36453981 DOI: 10.1111/php.13753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 11/14/2022] [Indexed: 12/05/2022]
Abstract
The mechanism of very efficient relaxation of the melanin-photoexcited states, responsible for the photoprotective action of the pigment, remains a subject for intense investigation. The most recent study by C. Grieco, F. Kohl, and B. Kohler, entitled "Ultrafast radical photogeneration pathways in eumelanin," addresses key issues of melanin photophysics and photochemistry. By using femtosecond broad-band pump probe-transient absorption measurements, the researchers were able to identify the absorption spectrum of DOPA melanin radicals for the first time and proposed two distinct mechanisms of radical formation-photoionization and photoinduced charge separation. The observed photodynamic of melanin radicals suggests a new paradigm in which the ultrafast excited state deactivation is due to the efficient recombination of melanin radicals created promptly by photoexcitation.
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Affiliation(s)
- Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
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18
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Mavridi-Printezi A, Menichetti A, Ferrazzano L, Montalti M. Reversible Supramolecular Noncovalent Self-Assembly Determines the Optical Properties and the Formation of Melanin-like Nanoparticles. J Phys Chem Lett 2022; 13:9829-9833. [PMID: 36250623 PMCID: PMC9620075 DOI: 10.1021/acs.jpclett.2c02239] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/05/2022] [Indexed: 05/31/2023]
Abstract
The role of noncovalent supramolecular self-assembly in the formation of melanin-like NP, as well as the nature of the electronic transition at the basis of their unique optical properties, is strongly debated. Here we demonstrate that, during the first stage of formation of synthetic melanin, polydopamine (PDA), a small fraction of the molecular precursor dopamine (DA) is oxidized to quinone (Q) and a simple supramolecular charge-transfer (CT) adduct is formed thanks to the electron donor and electron acceptor properties of DA and Q, respectively. This adduct, also detectable by HPLC-MS, presents the broad absorption band in the red-NIR region typical of melanin-like materials. Importantly, its disaggregation upon dilution can be easily detected since it leads to the disappearance of the CT band, indicating the reversibility of the process. Moreover, the stability constant K of the CT adduct could be obtained using a simple association model.
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19
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The photoprotection mechanism in the black-brown pigment eumelanin. Proc Natl Acad Sci U S A 2022; 119:e2212343119. [PMID: 36227945 PMCID: PMC9618045 DOI: 10.1073/pnas.2212343119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The natural black-brown pigment eumelanin protects humans from high-energy UV photons by absorbing and rapidly dissipating their energy before proteins and DNA are damaged. The extremely weak fluorescence of eumelanin points toward nonradiative relaxation on the timescale of picoseconds or shorter. However, the extreme chemical and physical complexity of eumelanin masks its photoprotection mechanism. We sought to determine the electronic and structural relaxation pathways in eumelanin using three complementary ultrafast optical spectroscopy methods: fluorescence, transient absorption, and stimulated Raman spectroscopies. We show that photoexcitation of chromophores across the UV-visible spectrum rapidly generates a distribution of visible excitation energies via ultrafast internal conversion among neighboring coupled chromophores, and then all these excitations relax on a timescale of ∼4 ps without transferring their energy to other chromophores. Moreover, these picosecond dynamics are shared by the monomeric building block, 5,6-dihydroxyindole-2-carboxylic acid. Through a series of solvent and pH-dependent measurements complemented by quantum chemical modeling, we show that these ultrafast dynamics are consistent with the partial excited-state proton transfer from the catechol hydroxy groups to the solvent. The use of this multispectroscopic approach allows the minimal functional unit in eumelanin and the role of exciton coupling and excited-state proton transfer to be determined, and ultimately reveals the mechanism of photoprotection in eumelanin. This knowledge has potential for use in the design of new soft optical components and organic sunscreens.
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20
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Ashfold MNR, Kim SK. Non-Born-Oppenheimer effects in molecular photochemistry: an experimental perspective. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2022; 380:20200376. [PMID: 35341307 DOI: 10.1098/rsta.2020.0376] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 06/28/2021] [Indexed: 06/14/2023]
Abstract
Non-adiabatic couplings between Born-Oppenheimer (BO)-derived potential energy surfaces are now recognized as pivotal in describing the non-radiative decay of electronically excited molecules following photon absorption. This opinion piece illustrates how non-BO effects provide photostability to many biomolecules when exposed to ultraviolet radiation, yet in many other cases are key to facilitating 'reactive' outcomes like isomerization and bond fission. The examples are presented in order of decreasing molecular complexity, spanning studies of organic sunscreen molecules in solution, through two families of heteroatom containing aromatic molecules and culminating with studies of isolated gas phase H2O molecules that afford some of the most detailed insights yet available into the cascade of non-adiabatic couplings that enable the evolution from photoexcited molecule to eventual products. This article is part of the theme issue 'Chemistry without the Born-Oppenheimer approximation'.
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Affiliation(s)
| | - Sang Kyu Kim
- Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea
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21
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Sasikumar D, Vinod K, Sunny J, Hariharan M. Exciton interactions in helical crystals of a hydrogen-bonded eumelanin monomer. Chem Sci 2022; 13:2331-2338. [PMID: 35310511 PMCID: PMC8864807 DOI: 10.1039/d1sc06755a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 01/19/2022] [Indexed: 12/04/2022] Open
Abstract
Eumelanin, a naturally occurring group of heterogeneous polymers/aggregates providing photoprotection to living organisms, consist of 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) building blocks. Despite their prevalence in the animal world, the structure and therefore the mechanism behind the photoprotective broadband absorption and non-radiative decay of eumelanin remain largely unknown. As a small step towards solving the incessant mystery, DHI is crystallized in a non-protic solvent environment to obtain DHI crystals having a helical packing motif. The present approach reflects the solitary directional effect of hydrogen bonds between the DHI chromophores for generating the crystalline assembly and filters out any involvement of the surrounding solvent environment. The DHI single crystals having an atypical chiral packing motif (P212121 Sohncke space group) incorporate enantiomeric zig-zag helical stacks arranged in a herringbone fashion with respect to each other. Each of the zig-zag helical stacks originates from a bifurcated hydrogen bonding interaction between the hydroxyl substituents in adjacent DHI chromophores which act as the backbone structure for the helical assembly. Fragment-based excited state analysis performed on the DHI crystalline assembly demonstrates exciton delocalization along the DHI units that connect each enantiomeric helical stack while, within each stack, the excitons remain localized. Fascinatingly, over the time evolution for generation of single-crystals of the DHI-monomer, mesoscopic double-helical crystals are formed, possibly attributed to the presence of covalently connected DHI trimers in chloroform solution. The oligomeric DHI (in line with the chemical disorder model) along with the characteristic crystalline packing observed for DHI provides insights into the broadband absorption feature exhibited by the chromophore. Single crystals of DHI monomer, a eumelanin precursor, adopt an atypical chiral packing arrangement incorporating enantiomeric zig-zag helical stacks while its covalently connected DHI trimer forms double-helical crystals in the mesoscopic scale.![]()
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Affiliation(s)
- Devika Sasikumar
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
| | - Kavya Vinod
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
| | - Jeswin Sunny
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram Maruthamala P.O., Vithura Thiruvananthapuram Kerala 695551 India
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22
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Bosch D, Wang J, Blancafort L. Fingerprint-based deep neural networks can model thermodynamic and optical properties of eumelanin DHI dimers. Chem Sci 2022; 13:8942-8946. [PMID: 36091209 PMCID: PMC9365084 DOI: 10.1039/d2sc02461f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/03/2022] [Indexed: 11/21/2022] Open
Abstract
Eumelanin is the biopolymer responsible for photoprotection in living beings and holds great promise as a smart biomaterial, but its detailed structure has not been characterized experimentally. Theoretical models are urgently needed to improve our knowledge of eumelanin's function and exploit its properties, but the enormous amount of possible oligomer components has made modelling not possible until now. Here we show that the stability and lowest vertical optical absorption of 5,6-dihydroxyindole (DHI) eumelanin dimer components can be modeled with deep neural networks, using fingerprint-like molecular representations as input. In spite of the modest data set size, average errors of only 6 and 9% for stability and S1 absorption energy are obtained. Our fingerprints code the connectivity and oxidation patterns of the dimers in a straightforward, unambiguous way and can be extended to larger oligomers. This proof-of-principle work shows that machine learning can be applied to help solve the structural challenge of melanin. Solving the challenge of melanin structure is important to realize its potential as smart biomaterial. By modeling the properties of eumelanin dimers we show that machine learning can be used to solve this problem.![]()
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Affiliation(s)
- Daniel Bosch
- Departament de Química, Institut de Química Computacional i Catàlisi, Universitat de Girona. Facultat de Ciències, C/M. A. Capmany 69, 17003 Girona, Spain
| | - Jun Wang
- Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials, Jiangsu Engineering Laboratory for Environment Functional Materials, Huaiyin Normal University, No. 111 West Changjiang Road, Huaian 223300, Jiangsu, P. R. China
| | - Lluís Blancafort
- Departament de Química, Institut de Química Computacional i Catàlisi, Universitat de Girona. Facultat de Ciències, C/M. A. Capmany 69, 17003 Girona, Spain
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23
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Mavridi-Printezi A, Menichetti A, Guernelli M, Montalti M. The Photophysics and Photochemistry of Melanin- Like Nanomaterials Depend on Morphology and Structure. Chemistry 2021; 27:16309-16319. [PMID: 34505731 PMCID: PMC9291563 DOI: 10.1002/chem.202102479] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 12/12/2022]
Abstract
Melanin‐like nanomaterials have found application in a large variety of high economic and social impact fields as medicine, energy conversion and storage, photothermal catalysis and environmental remediation. These materials have been used mostly for their optical and electronic properties, but also for their high biocompatibility and simplicity and versatility of preparation. Beside this, their chemistry is complex and it yields structures with different molecular weight and composition ranging from oligomers, to polymers as well as nanoparticles (NP). The comprehension of the correlation of the different compositions and morphologies to the optical properties of melanin is still incomplete and challenging, even if it is fundamental also from a technological point of view. In this minireview we focus on scientific papers, mostly recent ones, that indeed examine the link between composition and structural feature and photophysical and photochemical properties proposing this approach as a general one for future research.
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Affiliation(s)
| | - Arianna Menichetti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Moreno Guernelli
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Marco Montalti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
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24
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Understanding the way eumelanin works: A unique example of properties and skills driven by molecular heterogeneity. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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25
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Coy E, Iatsunskyi I, Colmenares JC, Kim Y, Mrówczyński R. Polydopamine Films with 2D-like Layered Structure and High Mechanical Resilience. ACS APPLIED MATERIALS & INTERFACES 2021; 13:23113-23120. [PMID: 33969981 PMCID: PMC8289185 DOI: 10.1021/acsami.1c02483] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/28/2021] [Indexed: 05/14/2023]
Abstract
Highly oriented, layered, and mechanically resilient films of polydopamine (PDA) have been synthesized from the air/water interface. The films show a unique layered structure, as shown by scanning and transmission electron studies (SEM/TEM) and X-ray diffraction analysis (XRD), which resemble that of 2D layered materials. The films exhibit a composition typical of PDA-based materials, as evidenced by X-ray photoelectron spectroscopy (XPS); moreover, the samples present the distinctive resonance modes of PDA-based nanomaterials in Raman and infrared spectroscopy (FTIR) experiments. The presence of highly ordinated 3-4 protomolecule stacking, taking place at the air/water interface, with a unique eumelanin-like supramolecular arrangement is presented. Moreover, the films show superior mechanical resilience with E = 13 ± 4 GPa and H = 0.21 ± 0.03 GPa, as revealed by nanoindentation experiments, making them highly resilient and easily transferable. Finally, the ordering induced by the interface opens many possibilities for further studies, including those regarding the supramolecular structure on PDA due to their similarity to 2D layered materials.
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Affiliation(s)
- Emerson Coy
- NanoBioMedical
Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland
| | - Igor Iatsunskyi
- NanoBioMedical
Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland
| | - Juan Carlos Colmenares
- Institute
of Physical Chemistry, Polish Academy of
Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Yeonho Kim
- Research
Institute of Basic Sciences, Incheon National
University, Incheon 22012, Republic of Korea
| | - Radosław Mrówczyński
- Faculty
of Chemistry, Adam Mickiewicz University, ul. Uniwersytet Poznańskiego
8, 61-614 Poznań, Poland
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26
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Galeb HA, Wilkinson EL, Stowell AF, Lin H, Murphy ST, Martin‐Hirsch PL, Mort RL, Taylor AM, Hardy JG. Melanins as Sustainable Resources for Advanced Biotechnological Applications. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000102. [PMID: 33552556 PMCID: PMC7857133 DOI: 10.1002/gch2.202000102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/04/2020] [Indexed: 05/17/2023]
Abstract
Melanins are a class of biopolymers that are widespread in nature and have diverse origins, chemical compositions, and functions. Their chemical, electrical, optical, and paramagnetic properties offer opportunities for applications in materials science, particularly for medical and technical uses. This review focuses on the application of analytical techniques to study melanins in multidisciplinary contexts with a view to their use as sustainable resources for advanced biotechnological applications, and how these may facilitate the achievement of the United Nations Sustainable Development Goals.
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Affiliation(s)
- Hanaa A. Galeb
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Department of ChemistryScience and Arts CollegeRabigh CampusKing Abdulaziz UniversityJeddah21577Saudi Arabia
| | - Emma L. Wilkinson
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Alison F. Stowell
- Department of Organisation, Work and TechnologyLancaster University Management SchoolLancaster UniversityLancasterLA1 4YXUK
| | - Hungyen Lin
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
| | - Samuel T. Murphy
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
| | - Pierre L. Martin‐Hirsch
- Lancashire Teaching Hospitals NHS TrustRoyal Preston HospitalSharoe Green LanePrestonPR2 9HTUK
| | - Richard L. Mort
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Adam M. Taylor
- Lancaster Medical SchoolLancaster UniversityLancasterLA1 4YWUK
| | - John G. Hardy
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
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27
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Mavridi-Printezi A, Guernelli M, Menichetti A, Montalti M. Bio-Applications of Multifunctional Melanin Nanoparticles: From Nanomedicine to Nanocosmetics. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E2276. [PMID: 33212974 PMCID: PMC7698489 DOI: 10.3390/nano10112276] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/05/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022]
Abstract
Bioinspired nanomaterials are ideal components for nanomedicine, by virtue of their expected biocompatibility or even complete lack of toxicity. Natural and artificial melanin-based nanoparticles (MNP), including polydopamine nanoparticles (PDA NP), excel for their extraordinary combination of additional optical, electronic, chemical, photophysical, and photochemical properties. Thanks to these features, melanin plays an important multifunctional role in the design of new platforms for nanomedicine where this material works not only as a mechanical support or scaffold, but as an active component for imaging, even multimodal, and simple or synergistic therapy. The number of examples of bio-applications of MNP increased dramatically in the last decade. Here, we review the most recent ones, focusing on the multiplicity of functions that melanin performs in theranostics platforms with increasing complexity. For the sake of clarity, we start analyzing briefly the main properties of melanin and its derivative as well as main natural sources and synthetic methods, moving to imaging application from mono-modal (fluorescence, photoacoustic, and magnetic resonance) to multi-modal, and then to mono-therapy (drug delivery, anti-oxidant, photothermal, and photodynamic), and finally to theranostics and synergistic therapies, including gene- and immuno- in combination to photothermal and photodynamic. Nanomedicine aims not only at the treatment of diseases, but also to their prevention, and melanin in nature performs a protective action, in the form of nanopigment, against UV-Vis radiations and oxidants. With these functions being at the border between nanomedicine and cosmetics nanotechnology, recently examples of applications of artificial MNP in cosmetics are increasing, paving the road to the birth of the new science of nanocosmetics. In the last part of this review, we summarize and discuss these important recent results that establish evidence of the interconnection between nanomedicine and cosmetics nanotechnology.
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Affiliation(s)
- Alexandra Mavridi-Printezi
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.-P.); (M.G.); (A.M.)
| | - Moreno Guernelli
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.-P.); (M.G.); (A.M.)
| | - Arianna Menichetti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.-P.); (M.G.); (A.M.)
| | - Marco Montalti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.-P.); (M.G.); (A.M.)
- Tecnopolo di Rimini, Via Campana 71, 47922 Rimini, Italy
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28
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Grieco C, Kohl FR, Hanes AT, Kohler B. Probing the heterogeneous structure of eumelanin using ultrafast vibrational fingerprinting. Nat Commun 2020; 11:4569. [PMID: 32917892 PMCID: PMC7486937 DOI: 10.1038/s41467-020-18393-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 08/18/2020] [Indexed: 11/25/2022] Open
Abstract
Eumelanin is a brown-black biological pigment with sunscreen and radical scavenging functions important to numerous organisms. Eumelanin is also a promising redox-active material for energy conversion and storage, but the chemical structures present in this heterogeneous pigment remain unknown, limiting understanding of the properties of its light-responsive subunits. Here, we introduce an ultrafast vibrational fingerprinting approach for probing the structure and interactions of chromophores in heterogeneous materials like eumelanin. Specifically, transient vibrational spectra in the double-bond stretching region are recorded for subsets of electronic chromophores photoselected by an ultrafast excitation pulse tuned through the UV-visible spectrum. All subsets show a common vibrational fingerprint, indicating that the diverse electronic absorbers in eumelanin, regardless of transition energy, contain the same distribution of IR-active functional groups. Aggregation of chromophores diverse in oxidation state is the key structural property underlying the universal, ultrafast deactivation behavior of eumelanin in response to photoexcitation with any wavelength.
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Affiliation(s)
- Christopher Grieco
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Forrest R Kohl
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Alex T Hanes
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, USA.
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29
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Yakimov BP, Shirshin EA, Schleusener J, Allenova AS, Fadeev VV, Darvin ME. Melanin distribution from the dermal-epidermal junction to the stratum corneum: non-invasive in vivo assessment by fluorescence and Raman microspectroscopy. Sci Rep 2020; 10:14374. [PMID: 32873804 PMCID: PMC7463016 DOI: 10.1038/s41598-020-71220-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/11/2020] [Indexed: 12/11/2022] Open
Abstract
The fate of melanin in the epidermis is of great interest due to its involvement in numerous physiological and pathological processes in the skin. Melanin localization can be assessed ex vivo and in vivo using its distinctive optical properties. Melanin exhibits a characteristic Raman spectrum band shape and discernible near-infrared excited (NIR) fluorescence. However, a detailed analysis of the capabilities of depth-resolved confocal Raman and fluorescence microspectroscopy in the evaluation of melanin distribution in the human skin is lacking. Here we demonstrate how the fraction of melanin at different depths in the human skin in vivo can be estimated from its Raman spectra (bands at 1,380 and 1,570 cm-1) using several procedures including a simple ratiometric approach, spectral decomposition and non-negative matrix factorization. The depth profiles of matrix factorization components specific to melanin, collagen and natural moisturizing factor provide information about their localization in the skin. The depth profile of the collagen-related matrix factorization component allows for precise determination of the dermal-epidermal junction, i.e. the epidermal thickness. Spectral features of fluorescence background originating from melanin were found to correlate with relative intensities of the melanin Raman bands. We also hypothesized that NIR fluorescence in the skin is not originated solely from melanin, and the possible impact of oxidized species should be taken into account. The ratio of melanin-related Raman bands at 1,380 and 1,570 cm-1 could be related to melanin molecular organization. The proposed combined analysis of the Raman scattering signal and NIR fluorescence could be a useful tool for rapid non-invasive in vivo diagnostics of melanin-related processes in the human skin.
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Affiliation(s)
- B P Yakimov
- Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskie Gory, Moscow, Russia, 119991
- Medical Research and Education Center, M.V. Lomonosov Moscow State University, Lomonosovsky Prospect 27/10, Moscow, Russia, 119991
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University, Trubetskaya 8-2, Moscow, Russia, 119991
| | - E A Shirshin
- Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskie Gory, Moscow, Russia, 119991.
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University, Trubetskaya 8-2, Moscow, Russia, 119991.
- Institute of Spectroscopy of the Russian Academy of Sciences, Fizicheskaya Str., 5, 108840, Troitsk, Moscow, Russia.
| | - J Schleusener
- Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany
| | - A S Allenova
- Medical Research and Education Center, M.V. Lomonosov Moscow State University, Lomonosovsky Prospect 27/10, Moscow, Russia, 119991
- Division of Immune-Mediated Skin Diseases, Sechenov First Moscow State Medical University, Trubetskaya 8-2, Moscow, Russia, 119991
| | - V V Fadeev
- Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskie Gory, Moscow, Russia, 119991
| | - M E Darvin
- Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.
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30
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Manini P, Lino V, D'Errico G, Reale S, Napolitano A, De Angelis F, d'Ischia M. “Blackness” is an index of redox complexity in melanin polymers. Polym Chem 2020. [DOI: 10.1039/d0py00700e] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Blackness as an emergent property associated with redox disorder and π-electron complexity in melanin polymers.
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Affiliation(s)
- Paola Manini
- Department of Chemical Sciences
- University of Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Napoli
- Italy
| | - Valeria Lino
- Department of Chemical Sciences
- University of Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Napoli
- Italy
| | - Gerardino D'Errico
- Department of Chemical Sciences
- University of Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Napoli
- Italy
| | - Samantha Reale
- Department of Physical and Chemical Sciences
- University of L'Aquila
- L'Aquila
- Italy
| | - Alessandra Napolitano
- Department of Chemical Sciences
- University of Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Napoli
- Italy
| | | | - Marco d'Ischia
- Department of Chemical Sciences
- University of Napoli Federico II
- Complesso Universitario Monte S. Angelo
- Napoli
- Italy
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