1
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Xie W, Dhinojwala A, Gianneschi NC, Shawkey MD. Interactions of Melanin with Electromagnetic Radiation: From Fundamentals to Applications. Chem Rev 2024; 124:7165-7213. [PMID: 38758918 DOI: 10.1021/acs.chemrev.3c00858] [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: 05/19/2024]
Abstract
Melanin, especially integumentary melanin, interacts in numerous ways with electromagnetic radiation, leading to a set of critical functions, including radiation protection, UV-protection, pigmentary and structural color productions, and thermoregulation. By harnessing these functions, melanin and melanin-like materials can be widely applied to diverse applications with extraordinary performance. Here we provide a unified overview of the melanin family (all melanin and melanin-like materials) and their interactions with the complete electromagnetic radiation spectrum (X-ray, Gamma-ray, UV, visible, near-infrared), which until now has been absent from the literature and is needed to establish a solid fundamental base to facilitate their future investigation and development. We begin by discussing the chemistries and morphologies of both natural and artificial melanin, then the fundamentals of melanin-radiation interactions, and finally the exciting new developments in high-performance melanin-based functional materials that exploit these interactions. This Review provides both a comprehensive overview and a discussion of future perspectives for each subfield of melanin that will help direct the future development of melanin from both fundamental and applied perspectives.
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Affiliation(s)
- Wanjie Xie
- Department of Biology, Evolution and Optics of Nanostructure Group, University of Ghent, Gent 9000, Belgium
| | - Ali Dhinojwala
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Nathan C Gianneschi
- Department of Chemistry, Department of Materials Science and Engineering, Department of Biomedical Engineering, Simpson-Querrey Institute, Chemistry of Life Processes Institute, Lurie Cancer Center, and International Institute of Nanotechnology, Northwestern University, Evanston, Illinois 60208, United States
| | - Matthew D Shawkey
- Department of Biology, Evolution and Optics of Nanostructure Group, University of Ghent, Gent 9000, Belgium
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2
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Vinod K, Jadhav SD, Hariharan M. Room Temperature Phosphorescence in Crystalline Iodinated Eumelanin Monomer. Chemistry 2024; 30:e202400499. [PMID: 38502668 DOI: 10.1002/chem.202400499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 03/01/2024] [Accepted: 03/19/2024] [Indexed: 03/21/2024]
Abstract
We report the room temperature phosphorescence upon iodination on a crystalline eumelanin monomer with shielded hydroxyl moieties, ethyl 5,6-dimethoxyindole-2-carboxylate (DMICE). Ultrafast intersystem crossing (ISC) is observed in the iodinated (IDMICE) as well as brominated (BDMICE) analogues of the eumelanin monomer derivative in solution. The triplet quantum yields (φT) and intersystem crossing rates (kISC) of the halogenated eumelanin derivatives areφ T B D M I C E ${{\phi{} }_{T}^{BDMICE}}$ =25.4±1.1 %;k I S C B D M I C E ${{k}_{ISC}^{BDMICE}}$ =1.95×109 s-1 andφ T I D M I C E ${{\phi{} }_{T}^{IDMICE}}$ =59.1±1.6 %;k I S C I D M I C E = ${{k}_{ISC}^{IDMICE}=}$ 1.36×1010 s-1, as monitored using transient absorption spectroscopy. Theoretical calculations based on nuclear ensemble method reveal that computed kISC and spin-orbit coupling matrix elements for eumelanin derivatives are larger for IDMICE relative to BDMICE. The halogen and π-π interactions, with distinct excitonic coupling and higher ISC rate promote phosphorescence in IDMICE molecular crystals. Accessing triplet excited states and resultant photoluminescence through structural modification of eumelanin scaffolds paves way for exploring the versatility of eumelanin-inspired molecules as bio-functional materials.
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Affiliation(s)
- Kavya Vinod
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram, 695551, Kerala, India
| | - Sohan D Jadhav
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram, 695551, Kerala, India
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER TVM), Maruthamala P.O., Vithura, Thiruvananthapuram, 695551, Kerala, India
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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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Olejnik A, Polaczek K, Szkodo M, Stanisławska A, Ryl J, Siuzdak K. Laser-Induced Graphitization of Polydopamine on Titania Nanotubes. ACS APPLIED MATERIALS & INTERFACES 2023; 15. [PMID: 37915241 PMCID: PMC10658452 DOI: 10.1021/acsami.3c11580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 11/03/2023]
Abstract
Since the discovery of laser-induced graphite/graphene, there has been a notable surge of scientific interest in advancing diverse methodologies for their synthesis and applications. This study focuses on the utilization of a pulsed Nd:YAG laser to achieve graphitization of polydopamine (PDA) deposited on the surface of titania nanotubes. The partial graphitization is corroborated through Raman and XPS spectroscopies and supported by water contact angle, nanomechanical, and electrochemical measurements. Reactive molecular dynamics simulations confirm the possibility of graphitization in the nanosecond time scale with the evolution of NH3, H2O, and CO2 gases. A thorough exploration of the lasing parameter space (wavelength, pulse energy, and number of pulses) was conducted with the aim of improving either electrochemical activity or photocurrent generation. Whereas the 532 nm laser pulses interacted mostly with the PDA coating, the 365 nm pulses were absorbed by both PDA and the substrate nanotubes, leading to a higher graphitization degree. The majority of the photocurrent and quantum efficiency enhancement is observed in the visible light between 400 and 550 nm. The proposed composite is applied as a photoelectrochemical (PEC) sensor of serotonin in nanomolar concentrations. Because of the suppressed recombination and facilitated charge transfer caused by the laser graphitization, the proposed composite exhibits significantly enhanced PEC performance. In the sensing application, it showed superior sensitivity and a limit of detection competitive with nonprecious metal materials.
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Affiliation(s)
- Adrian Olejnik
- Department
of Metrology and Optoelectronics, Faculty of Electronics, Telecommunications
and Informatics, Gdańsk University
of Technology, Narutowicza 11/12 St., Gdańsk 80-233, Poland
- Centre
for Plasma and Laser Engineering, The Szewalski
Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14 St., Gdańsk 80-231, Poland
| | - Krzysztof Polaczek
- Centre
for Plasma and Laser Engineering, The Szewalski
Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14 St., Gdańsk 80-231, Poland
- Department
of Biomedical Chemistry, Faculty of Chemistry
University of Gdansk, Wita Stwosza 63 St, Gdańsk 80-308, Poland
| | - Marek Szkodo
- Institute
of Manufacturing and Materials Technology, Faculty of Mechanical Engineering
and Ship Technology, Gdańsk University
of Technology, Narutowicza 11/12 St., Gdańsk 80-233, Poland
| | - Alicja Stanisławska
- Institute
of Manufacturing and Materials Technology, Faculty of Mechanical Engineering
and Ship Technology, Gdańsk University
of Technology, Narutowicza 11/12 St., Gdańsk 80-233, Poland
| | - Jacek Ryl
- Institute
of Nanotechnology and Materials Engineering and Advanced Materials
Center, Gdańsk University of Technology, Narutowicza 11/12, Gdańsk 80-233, Poland
| | - Katarzyna Siuzdak
- Centre
for Plasma and Laser Engineering, The Szewalski
Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14 St., Gdańsk 80-231, Poland
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Menichetti A, Mavridi-Printezi A, Mordini D, Montalti M. Polydopamine-Based Nanoprobes Application in Optical Biosensing. BIOSENSORS 2023; 13:956. [PMID: 37998131 PMCID: PMC10669744 DOI: 10.3390/bios13110956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/13/2023] [Accepted: 10/24/2023] [Indexed: 11/25/2023]
Abstract
Polydopamine (PDA), the synthetic counterpart of melanin, is a widely investigated bio-inspired material for its chemical and photophysical properties, and in the last few years, bio-application of PDA and PDA-based materials have had a dramatic increase. In this review, we described PDA application in optical biosensing, exploring its multiple roles as a nanomaterial. In optical sensing, PDA can not only be used for its intrinsic fluorescent and photoacoustic properties as a probe: in some cases, a sample optical signal can be derived by melanin generation in situ or it can be enhanced in another material thanks to PDA modification. The various possibilities of PDA use coupled with its biocompatibility will indeed widen even more its application in optical bioimaging.
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Affiliation(s)
| | | | | | - Marco Montalti
- Department of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, 40126 Bologna, Italy; (A.M.); (A.M.-P.); (D.M.)
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DeMarco M, Ballard M, Grage E, Nourigheimasi F, Getter L, Shafiee A, Ghadiri E. Enhanced photochemical activity and ultrafast photocarrier dynamics in sustainable synthetic melanin nanoparticle-based donor-acceptor inkjet-printed molecular junctions. NANOSCALE 2023; 15:14346-14364. [PMID: 37602764 DOI: 10.1039/d3nr02387g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
Melanin is a stable, widely light-absorbing, photoactive, and biocompatible material viable for energy conversion, photocatalysis, and bioelectronic applications. To achieve multifunctional nanostructures, we synthesized melanin nanoparticles of uniform size and controlled chemical composition (dopamelanin and eumelanin) and used them with titanium dioxide to fabricate donor-acceptor bilayers. Their size enhances the surface-to-volume ratio important for any surface-mediated functionality, such as photocatalysis, sensing, and drug loading and release, while controlling their chemical composition enables to control the film's functionality and reproducibility. Inkjet printing uniquely allowed us to control the deposited amount of materials with minimum ink waste suitable for reproducible materials deposition. We studied the photochemical characteristics of the donor-acceptor melanin-TiO2 nanostructured films via photocatalytic degradation of methylene blue dye under selective UV-NIR and Vis-NIR irradiation conditions. Under both irradiation conditions, they exhibited photocatalytic characteristics superior to pure melanin and, under UV-NIR irradiation, superior to TiO2 alone; TiO2 is photoactive only under UV irradiation. The enhanced photocatalytic characteristics of the melanin-TiO2 nanostructured bilayer films, particularly when excited by visible light, point to charge separation at the melanin-TiO2 interface as a possible mechanism. We performed ultrafast laser spectroscopy to investigate the photochemical characteristics of pure melanin and the melanin-TiO2 constructs and found that their time-resolved photoexcited spectral patterns differ. We performed singular value decomposition analysis to quantitatively deconvolute and compare the dynamics of photochemical processes for melanin and melanin-TiO2 heterostructures. This observation supports electronic interactions, namely, interfacial charge separation at the melanin and TiO2 interface. The excited-state relaxation in melanin-TiO2 increases markedly from 5 ps to 400 ps. The results are remarkable for the future intriguing application of melanin-based constructs for bioelectronics and energy conversion.
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Affiliation(s)
- Max DeMarco
- Chemistry Department, Wake Forest University, USA.
- Center for Functional Materials, Wake Forest University, USA
| | - Matthew Ballard
- Chemistry Department, Wake Forest University, USA.
- Center for Functional Materials, Wake Forest University, USA
| | - Elinor Grage
- Chemistry Department, Wake Forest University, USA.
- Center for Functional Materials, Wake Forest University, USA
| | - Farnoush Nourigheimasi
- Chemistry Department, Wake Forest University, USA.
- Center for Functional Materials, Wake Forest University, USA
| | - Lillian Getter
- Chemistry Department, Wake Forest University, USA.
- Center for Functional Materials, Wake Forest University, USA
| | - Ashkan Shafiee
- Wake Forest School of Medicine, Wake Forest University, USA
- Center for Functional Materials, Wake Forest University, USA
| | - Elham Ghadiri
- Chemistry Department, Wake Forest University, USA.
- Wake Forest School of Medicine, Wake Forest University, USA
- Center for Functional Materials, Wake Forest University, USA
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7
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Mavridi-Printezi A, Menichetti A, Mordini D, Amorati R, Montalti M. Recent Applications of Melanin-like Nanoparticles as Antioxidant Agents. Antioxidants (Basel) 2023; 12:antiox12040863. [PMID: 37107238 PMCID: PMC10135245 DOI: 10.3390/antiox12040863] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/24/2023] [Accepted: 03/29/2023] [Indexed: 04/05/2023] Open
Abstract
Nanosized antioxidants are highly advantageous in terms of versatility and pharmacokinetics, with respect to conventional molecular ones. Melanin-like materials, artificial species inspired by natural melanin, combine recognized antioxidant (AOX) activity with a unique versatility of preparation and modification. Due to this versatility and documented biocompatibility, artificial melanin has been incorporated into a variety of nanoparticles (NP) in order to give new platforms for nanomedicine with enhanced AOX activity. In this review article, we first discuss the chemical mechanisms behind the AOX activity of materials in the context of the inhibition of the radical chain reaction responsible for the peroxidation of biomolecules. We also focus briefly on the AOX properties of melanin-like NP, considering the effect of parameters such as size, preparation methods and surface functionalization on them. Then, we consider the most recent and relevant applications of AOX melanin-like NPs that are able to counteract ferroptosis and be involved in the treatment of important diseases that affect, e.g., the cardiovascular and nervous systems, as well as the kidneys, liver and articulations. A specific section will be dedicated to cancer treatment, since the role of melanin in this context is still very debated. Finally, we propose future strategies in AOX development for a better chemical understanding of melanin-like materials. In particular, the composition and structure of these materials are still debated, and they present a high level of variability. Thus, a better understanding of the mechanism behind the interaction of melanin-like nanostructures with different radicals and highly reactive species would be highly advantageous for the design of more effective and specific AOX nano-agents.
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Affiliation(s)
| | - 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
| | - Riccardo Amorati
- 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
- Tecnopolo di Rimini, Via Dario Campana 71, 47921 Rimini, Italy
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Surface-facilitated formation of polydopamine and its implications in melanogenesis. Colloids Surf B Biointerfaces 2023; 222:113068. [PMID: 36481509 DOI: 10.1016/j.colsurfb.2022.113068] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/25/2022] [Accepted: 11/30/2022] [Indexed: 12/02/2022]
Abstract
This manuscript examines influences of differently functionalized surfaces on the formation of solution-dispersed polydopamine (pDA). Glass vials functionalized with different functional groups provided a set of conditions with which the relationship between the area of active surface and the rate of pDA formation could be systematically studied. The results suggest that charged and polar surfaces accelerate pDA formation in solution, with the effect of -NH2 surfaces being exceptionally strong. In the vials, pDA formed as both forms of dispersions in solution and films at solid-liquid interface. Further analyses confirmed that both forms of pDA formed with -NH2 surfaces were chemically similar to conventional pDA synthesized without help of functional surfaces. Among short peptide-based amyloid fibers with defined surface functional groups, and those displaying lysines (-NH2) greatly accelerated the formation of pDA, consistent with the results of -NH2-functionalized vials. The results suggest that pDA formation may be facilitated by surface functional groups of solid-liquid interfaces, and have implications for the overlooked roles of amyloid fibers in biological melanogenesis.
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Structural Investigation of DHICA Eumelanin Using Density Functional Theory and Classical Molecular Dynamics Simulations. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238417. [PMID: 36500509 PMCID: PMC9738096 DOI: 10.3390/molecules27238417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/05/2022]
Abstract
Eumelanin is an important pigment, for example, in skin, hair, eyes, and the inner ear. It is a highly heterogeneous polymer with 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI) building blocks, of which DHICA is reported as the more abundant in natural eumelanin. The DHICA-eumelanin protomolecule consists of three building blocks, indole-2-carboxylic acid-5,6-quinone (ICAQ), DHICA and pyrrole-2,3,5-tricarboxylic acid (PTCA). Here, we focus on the self-assembly of DHICA-eumelanin using multi-microsecond molecular dynamics (MD) simulations at various concentrations in aqueous solutions. The molecule was first parameterized using density functional theory (DFT) calculations. Three types of systems were studied: (1) uncharged DHICA-eumelanin, (2) charged DHICA-eumelanin corresponding to physiological pH, and (3) a binary mixture of both of the above protomolecules. In the case of uncharged DHICA-eumelanin, spontaneous aggregation occurred and water molecules were present inside the aggregates. In the systems corresponding to physiological pH, all the carboxyl groups are negatively charged and the DHICA-eumelanin model has a net charge of -4. The effect of K+ ions as counterions was investigated. The results show high probability of binding to the deprotonated oxygens of the carboxylate anions in the PTCA moiety. Furthermore, the K+ counterions increased the solubility of DHICA-eumelanin in its charged form. A possible explanation is that the charged protomolecules favor binding to the K+ ions rather than aggregating and binding to other protomolecules. The binary mixtures show aggregation of uncharged DHICA-eumelanins; unlike the charged systems with no aggregation, a few charged DHICA-eumelanins are present on the surface of the uncharged aggregation, binding to the K+ ions.
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10
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Del Bino S, Ito S, Sok J, Wakamatsu K. 5,6-Dihydroxyindole eumelanin content in human skin with varying degrees of constitutive pigmentation. Pigment Cell Melanoma Res 2022; 35:622-626. [PMID: 35933709 PMCID: PMC9804219 DOI: 10.1111/pcmr.13062] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/21/2022] [Accepted: 08/03/2022] [Indexed: 01/05/2023]
Abstract
Human skin contains two distinct components: brown to black, insoluble eumelanin and light colored, alkaline-soluble pheomelanin. Eumelanin consists of 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) moieties, while pheomelanin consists of benzothiazine (BT) and benzothiazole (BZ) moieties. These melanin monomer units can be quantitatively analyzed through specific degradation products by high-performance liquid chromatography (HPLC). Alkaline hydrogen peroxide oxidation (AHPO) of eumelanin gives rise to pyrrole-2,3,5-tricarboxylic acid (PTCA) and pyrrole-2,3-dicarboxylic acid (PDCA) as specific degradation products of the DHICA and DHI moieties, respectively. BZ moiety in pheomelanin can be analyzed as thiazole-2,4,5-tricarboxylic acid (TTCA). By reductive hydrolysis with hydroiodic acid, BT moieties in pheomelanin can be analyzed as 4-amino-3-hydroxyphenylalanine (4-AHP). As a recently improved AHPO-HPLC method enabled a better characterization of PDCA, this prompted us to address the question of DHI to DHICA ratio in human skin samples with varying degrees of constitutive pigmentation ranging from very light to dark. Results showed for the first time the ratio of 4 moieties: DHI 35%, DHICA 41%, BZ 20%, and BT 4%. The ratio is constant regardless of the degree of pigmentation. The high content of DHICA moiety may impart an antioxidant property to the epidermis melanin.
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Affiliation(s)
| | - Shosuke Ito
- Institute for Melanin ChemistryFujita Health UniversityToyoakeJapan
| | - Juliette Sok
- L'Oreal Research and InnovationAulnay‐sous‐BoisFrance
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11
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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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12
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Aguilar-Ferrer D, Szewczyk J, Coy E. Recent developments in polydopamine-based photocatalytic nanocomposites for energy production: Physico-chemical properties and perspectives. Catal Today 2022. [DOI: 10.1016/j.cattod.2021.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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13
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Xia K, Zheng X, Wang Y, Zhong W, Dong Z, Ye Z, Zhang Z. Biomimetic Chiral Photonic Materials with Tunable Metallic Colorations Prepared from Chiral Melanin-like Nanorods for UV Shielding, Humidity Sensing, and Cosmetics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:8114-8124. [PMID: 35731984 DOI: 10.1021/acs.langmuir.2c01004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Many biological species combine the helical organization of cellulose or chitin microfibrils with broadband light absorption of black melanin to produce brilliant structural colors with metallic and glossy effects and other diverse functions. In this work, based on core-shell CNC@PDA chiral nanorods consisting of cellulose nanocrystals (CNCs) as the core and melanin-like polydopamine (PDA) as the shell that can form well-defined chiral liquid crystal phases, we report chiral photonic materials that closely mimic the unique coloration mechanisms and functionalities mastered by several biological species. The photonic films formed by such single CNC@PDA nanorods have brilliant iridescent structural colors originating from selective reflection of circularly polarized lights by the helical organization of CNC@PDAs across the films. Furthermore, the colors of such films have background-independent brightness, high visibility, and metallic effects that arise from the light absorption of the PDA component. Especially, the color ranges and metallic effects of the films can be conveniently tuned by varying the thickness of the PDA shell. In addition, the UV absorption and hygroscopic properties of PDA endow these CNC@PDA films with efficient broadband UV shielding and sensitive humidity-induced dynamic color changes. Due to the mussel-like superior adhesion of PDA, CNC@PDA-based photonic coatings can be formed conformably onto diverse kinds of substrates. A shiny eye shadow with viewing angle-dependent colorful patterns was used to demonstrate the potential applications. With combinations of multiple unique properties in one photonic material fabricated from a single building block, these CNC@PDA-based films are expected to have potential applications in cosmetics, UV protection, anticounterfeiting, chiral reflectors, etc.
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Affiliation(s)
- Ke Xia
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Xiaonan Zheng
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Yuhan Wang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Weiting Zhong
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Ziyue Dong
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Zihan Ye
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Zhenkun Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
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14
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Chang XP, Yu L, Zhang TS, Cui G. Quantum mechanics/molecular mechanics studies on the mechanistic photophysics of sunscreen oxybenzone in methanol solution. Phys Chem Chem Phys 2022; 24:13293-13304. [PMID: 35607908 DOI: 10.1039/d2cp01263d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, we have employed the QM(CASPT2//CASSCF)/MM method to explore the photophysical and photochemical mechanism of oxybenzone (OB) in methanol solution. Based on the optimized minima, conical intersections and crossing points, and minimum-energy reaction paths related to excited-state intramolecular proton transfer (ESIPT) and excited-state decay paths in the 1ππ*, 1nπ*, 3ππ*, 3nπ*, and S0 states, we have identified several feasible excited-state relaxation pathways for the initially populated S2(1ππ*) state to decay to the initial enol isomer' S0 state. The major one is the singlet-mediated and stretch-torsion coupled ESIPT pathway, in which the system first undergoes an essentially barrierless 1ππ* ESIPT process to generate the 1ππ* keto species, and finally realizes its ground state recovery through the subsequent carbonyl stretch-torsion facilitating S1 → S0 internal conversion (IC) and the reverse ground-state intramolecular proton transfer (GSIPT) process. The minor ones are related to intersystem crossing (ISC) processes. At the S2(1ππ*) minimum, an S2(1ππ*)/S1(1nπ*)/T2(3nπ*) three-state intersection region helps the S2 system branch into the T1 state through a S2 → S1 → T1 or S2 → T2 → T1 process. Once it has reached the T1 state, the system may relax to the S0 state via direct ISC or via subsequent nearly barrierless 3ππ* ESIPT to yield the T1 keto tautomer and ISC. The resultant S0 keto species significantly undergoes reverse GSIPT and only a small fraction yields the trans-keto form that relaxes back more slowly. However, due to small spin-orbit couplings at T1/S0 crossing points, the ISC to S0 state occurs very slowly. The present work rationalizes not only the ultrafast excited-state decay dynamics of OB but also its phosphorescence emission at low temperature.
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Affiliation(s)
- Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Li Yu
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
| | - Teng-Shuo Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, 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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15
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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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16
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Marcovici I, Coricovac D, Pinzaru I, Macasoi IG, Popescu R, Chioibas R, Zupko I, Dehelean CA. Melanin and Melanin-Functionalized Nanoparticles as Promising Tools in Cancer Research-A Review. Cancers (Basel) 2022; 14:1838. [PMID: 35406610 PMCID: PMC8998143 DOI: 10.3390/cancers14071838] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/24/2022] [Accepted: 04/01/2022] [Indexed: 12/25/2022] Open
Abstract
Cancer poses an ongoing global challenge, despite the substantial progress made in the prevention, diagnosis, and treatment of the disease. The existing therapeutic methods remain limited by undesirable outcomes such as systemic toxicity and lack of specificity or long-term efficacy, although innovative alternatives are being continuously investigated. By offering a means for the targeted delivery of therapeutics, nanotechnology (NT) has emerged as a state-of-the-art solution for augmenting the efficiency of currently available cancer therapies while combating their drawbacks. Melanin, a polymeric pigment of natural origin that is widely spread among many living organisms, became a promising candidate for NT-based cancer treatment owing to its unique physicochemical properties (e.g., high biocompatibility, redox behavior, light absorption, chelating ability) and innate antioxidant, photoprotective, anti-inflammatory, and antitumor effects. The latest research on melanin and melanin-like nanoparticles has extended considerably on many fronts, allowing not only efficient cancer treatments via both traditional and modern methods, but also early disease detection and diagnosis. The current paper provides an updated insight into the applicability of melanin in cancer therapy as antitumor agent, molecular target, and delivery nanoplatform.
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Affiliation(s)
- Iasmina Marcovici
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Dorina Coricovac
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Iulia Pinzaru
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Ioana Gabriela Macasoi
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Roxana Popescu
- Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (R.P.); (R.C.)
- Research Center ANAPATMOL, Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Raul Chioibas
- Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (R.P.); (R.C.)
| | - Istvan Zupko
- Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary;
| | - Cristina Adriana Dehelean
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
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17
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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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18
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Ding Y, Yang L, Shen J, Wei Y, Wang C. A novel fluorescent off–on probe based on 4-methylumbelliferone for highly sensitive determination of tyrosinase. NEW J CHEM 2022. [DOI: 10.1039/d2nj00799a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel fluorescent probe for high-sensitivity determination of tyrosinase, with 4-methylumbelliferone as the fluorophore and 3-hydroxybenzyl as the recognition group.
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Affiliation(s)
- Yu Ding
- College of Chemistry and Materials Science, Northwest University, 1 Xue Fu Avenue, Chang’an District, Xi’an 710127, P. R. China
| | - Lihong Yang
- College of Chemistry and Materials Science, Northwest University, 1 Xue Fu Avenue, Chang’an District, Xi’an 710127, P. R. China
| | - Jiwei Shen
- College of Chemistry and Materials Science, Northwest University, 1 Xue Fu Avenue, Chang’an District, Xi’an 710127, P. R. China
| | - Yinmao Wei
- College of Chemistry and Materials Science, Northwest University, 1 Xue Fu Avenue, Chang’an District, Xi’an 710127, P. R. China
| | - Chaozhan Wang
- College of Chemistry and Materials Science, Northwest University, 1 Xue Fu Avenue, Chang’an District, Xi’an 710127, P. R. China
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19
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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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20
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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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21
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Fast-response fluorescent probe with favorable water solubility for highly sensitive imaging of endogenous tyrosinase in living cells and zebrafish model. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2020.12.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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22
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Chang XP, Zhang TS, Fang YG, Cui G. Quantum Mechanics/Molecular Mechanics Studies on the Photophysical Mechanism of Methyl Salicylate. J Phys Chem A 2021; 125:1880-1891. [PMID: 33645980 DOI: 10.1021/acs.jpca.0c10589] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methyl salicylate (MS) as a subunit of larger salicylates found in commercial sunscreens has been shown to exhibit keto-enol tautomerization and dual fluorescence emission via excited-state intramolecular proton transfer (ESIPT) after the absorption of ultraviolet (UV) radiation. However, its excited-state relaxation mechanism is unclear. Herein, we have employed the quantum mechanics(CASPT2//CASSCF)/molecular mechanics method to explore the ESIPT and excited-state relaxation mechanism of MS in the lowest three electronic states, that is, S0, S1, and T1 states, in a methanol solution. Based on the optimized geometric and electronic structures, conical intersections and crossing points, and minimum-energy paths combined with the computed linearly interpolated Cartesian coordinate paths, the photophysical mechanism of MS has been proposed. The S1 state is a spectroscopically bright 1ππ* state in the Franck-Condon region. From the initially populated S1 state, there exist three nonradiative relaxation paths to repopulate the S0 state. In the first one, the S1 system (i.e., ketoB form) first undergoes an ESIPT path to generate an S1 tautomer (i.e., enol form) that exhibits a large Stokes shift in experiments. The generated S1 enol tautomer further evolves toward the nearby S1/S0 conical intersection and then hops to the S0 state, followed by the backward ground-state intramolecular proton transfer (GSIPT) to the initial ketoB form S0 state. In the second one, the S1 system first hops through the S1 → T1 intersystem crossing (ISC) to the T1 state, which then further decays to the S0 state via T1 → S0 ISC at the T1/S0 crossing point. In the third path, the T1 system that stems from the S1 → T1 ISC process via the S1/T1 crossing point first takes place a T1 ESIPT to generate a T1 enol tautomer, which can further decay to the S0 state via T1-to-S0 ISC. Finally, the GSIPT occurs to back the system to the initial ketoB form S0 state. Our present work could contribute to understanding the photophysics of MS and its derivatives.
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Affiliation(s)
- Xue-Ping Chang
- College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, P. R. China
| | - Teng-Shuo Zhang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Ye-Guang Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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23
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Cao W, Zhou X, McCallum NC, Hu Z, Ni QZ, Kapoor U, Heil CM, Cay KS, Zand T, Mantanona AJ, Jayaraman A, Dhinojwala A, Deheyn DD, Shawkey MD, Burkart MD, Rinehart JD, Gianneschi NC. Unraveling the Structure and Function of Melanin through Synthesis. J Am Chem Soc 2021; 143:2622-2637. [PMID: 33560127 DOI: 10.1021/jacs.0c12322] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Melanin is ubiquitous in living organisms across different biological kingdoms of life, making it an important, natural biomaterial. Its presence in nature from microorganisms to higher animals and plants is attributed to the many functions of melanin, including pigmentation, radical scavenging, radiation protection, and thermal regulation. Generally, melanin is classified into five types-eumelanin, pheomelanin, neuromelanin, allomelanin, and pyomelanin-based on the various chemical precursors used in their biosynthesis. Despite its long history of study, the exact chemical makeup of melanin remains unclear, and it moreover has an inherent diversity and complexity of chemical structure, likely including many functions and properties that remain to be identified. Synthetic mimics have begun to play a broader role in unraveling structure and function relationships of natural melanins. In the past decade, polydopamine, which has served as the conventional form of synthetic eumelanin, has dominated the literature on melanin-based materials, while the synthetic analogues of other melanins have received far less attention. In this perspective, we will discuss the synthesis of melanin materials with a special focus beyond polydopamine. We will emphasize efforts to elucidate biosynthetic pathways and structural characterization approaches that can be harnessed to interrogate specific structure-function relationships, including electron paramagnetic resonance (EPR) and solid-state nuclear magnetic resonance (ssNMR) spectroscopy. We believe that this timely Perspective will introduce this class of biopolymer to the broader chemistry community, where we hope to stimulate new opportunities in novel, melanin-based poly-functional synthetic materials.
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Affiliation(s)
| | | | | | | | - Qing Zhe Ni
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Utkarsh Kapoor
- Department of Chemical and Biomolecular Engineering, Colburn Laboratory, University of Delaware, Newark, Delaware 19716, United States
| | - Christian M Heil
- Department of Chemical and Biomolecular Engineering, Colburn Laboratory, University of Delaware, Newark, Delaware 19716, United States
| | - Kristine S Cay
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Tara Zand
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Alex J Mantanona
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Arthi Jayaraman
- Department of Chemical and Biomolecular Engineering, Colburn Laboratory, Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Dimitri D Deheyn
- Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, California 92093-0202, United States
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, The University of Ghent, 9000 Ghent, Belgium
| | - Michael D Burkart
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Jeffrey D Rinehart
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Nathan C Gianneschi
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
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24
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Ghosh P, Ghosh D. Effect of Dimerization on the Nonradiative Processes of Eumelanin Monomer. J Phys Chem B 2021; 125:547-556. [PMID: 33410319 DOI: 10.1021/acs.jpcb.0c10555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Eumelanin is a polymeric structure made of dihydroxyindole (DHI) as the basic motif. Since the oxidative polymerization of DHI forms the core of eumelanin, understanding the effect of polymerization on its optical and photoprotective properties is crucial to elucidate the structure-function relationship of eumelanin. In this work, we investigate the effect of dimerization of DHI on the photoprocesses of eumelanin. We observe that there are several low-energy conical intersections and energetically favorable pathways for deactivation of photoexcited dimeric DHI species. While the original deactivation modes of the monomers are still important, in dimers the intermonomer dihedral angles seem to play a central role.
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Affiliation(s)
- Paulami Ghosh
- 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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25
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Ghosh D. Computational aspects towards understanding the photoprocesses in eumelanin. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2020. [DOI: 10.1002/wcms.1505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Debashree Ghosh
- School of Chemical Sciences Indian Association for the Cultivation of Science Kolkata India
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26
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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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27
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Shin JH, Le NTK, Jang H, Lee T, Kang K. Supramolecular Regulation of Polydopamine Formation by Amyloid Fibers. Chemistry 2020; 26:5500-5507. [PMID: 32092201 DOI: 10.1002/chem.202000437] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/19/2020] [Indexed: 11/10/2022]
Abstract
Polydopamine (PD) and melanin species are chemically complex systems, the formation and properties of which are incompletely understood. Inspired by the role of functional amyloids in melanin biosynthesis, this paper examines the influences of the supramolecular structure of amyloids on oxidative polymerization of dopamine. Kinetic analyses on the formation of PD species in the presence of hen egg white lysozyme (HEWL) fibers or soluble HEWL revealed that both forms gave rise to the total quantity of PD species, but the rate of their formation could be accelerated only by the amyloid form. PD species formed with HEWL fibers showed a morphology of bundled fibers, whereas those with soluble HEWL had a mesh-like structure. Amyloid fibers of recombinant Pmel17 had properties similar to those of HEWL fibers in modulating PD formation. The results presented here suggest how nature designs functionality with an amyloid structure and can help understand and engineer chemistries of other functional amyloids.
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Affiliation(s)
- J H Shin
- Department of Applied Chemistry, Kyung Hee University, 1732 Deogyoung-daero, Yongin, Gyeonggi, 17104, Republic of Korea
| | - Nghia T K Le
- Department of Applied Chemistry, Kyung Hee University, 1732 Deogyoung-daero, Yongin, Gyeonggi, 17104, Republic of Korea
| | - Hongje Jang
- Department of Chemistry, Kwangwoon University, 20 Gwangwoon-ro, Nowon-gu, Seoul, 01897, Republic of Korea
| | - Taehoon Lee
- Department of Applied Chemistry, Kyung Hee University, 1732 Deogyoung-daero, Yongin, Gyeonggi, 17104, Republic of Korea
| | - Kyungtae Kang
- Department of Applied Chemistry, Kyung Hee University, 1732 Deogyoung-daero, Yongin, Gyeonggi, 17104, Republic of Korea
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CuO/Cu2O nanowire array photoelectrochemical biosensor for ultrasensitive detection of tyrosinase. Sci China Chem 2020. [DOI: 10.1007/s11426-020-9717-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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29
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Chen Y. Advances in fluorescent probes for detection and imaging of endogenous tyrosinase activity. Anal Biochem 2020; 594:113614. [DOI: 10.1016/j.ab.2020.113614] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 01/31/2020] [Accepted: 02/03/2020] [Indexed: 12/20/2022]
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30
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Norell J, Odelius M, Vacher M. Ultrafast dynamics of photo-excited 2-thiopyridone: Theoretical insights into triplet state population and proton transfer pathways. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:024101. [PMID: 32206689 PMCID: PMC7078009 DOI: 10.1063/1.5143228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/29/2020] [Indexed: 06/10/2023]
Abstract
Ultrafast non-adiabatic dynamics of the small heteroaromatic compound 2-thiopyridone has been studied with surface hopping simulations based on multi-configurational quantum chemistry. Initial excitation of the bright S 2 ( π , π * ) state is found to promptly relax to S 1 ( n , π * ) through in-plane motion. The subsequent dynamics are oppositely driven by out-of-plane motion, which results in both complex population transfers among all the available states and intersystem crossing predominantly through the "El-Sayed forbidden" S 1 ( n , π * ) to T 2 ( n , π * ) channel, through significant mixing of electronic excitation characters. Despite this complexity, the femto- to picosecond triplet population, expected from several spectroscopic measurements, is well described as a simple exponential decay of the singlet state manifold. No proton transfer is found in the reported trajectories, but two mechanisms for its possible mediation in previously reported experiments are proposed based on the observed structural dynamics: (i) ultrafast intra-molecular transfer driven by the initially coherent in-plane motion and (ii) inter-molecular solvent-mediated transfer driven by the out-of-plane modes that dominate the later motion.
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Affiliation(s)
- Jesper Norell
- Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Michael Odelius
- Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden
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31
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Grieco C, Empey JM, Kohl FR, Kohler B. Probing eumelanin photoprotection using a catechol:quinone heterodimer model system. Faraday Discuss 2019; 216:520-537. [PMID: 31012874 DOI: 10.1039/c8fd00231b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Eumelanin is a natural pigment with photoprotective and radical scavenging characteristics, which are vital for a multitude of living organisms. However, the molecular mechanisms behind these functions remain obscure, in part because eumelanin is a heterogeneous polymer composed of a complex assortment of structural and chemical domains. Despite uncertainty about its precise structure, the functional units of eumelanin are thought to include quinones in various oxidation states. Here, we investigate the photochemistry of a catechol : o-quinone heterodimer as a model system for uncovering the photoprotective roots of eumelanin. Ultrafast transient absorption measurements in the UV to near-IR spectral regions are used to identify the photochemical processes that follow selective excitation of the o-quinone in the heterodimer using 395 nm light. We find that both singlet and triplet o-quinone excited states induce hydrogen atom transfer from the catechol, forming semiquinone radical pairs that persist beyond 2.5 ns, which is the upper time limit accessible by our instrument. Furthermore, the hydrogen atom transfer reaction was found to occur 1000 times faster via the singlet channel. Excited state pathways such as these may be important in eumelanin, where similar hydrogen-bonded interfaces are believed to exist between catechol and o-quinone functional groups.
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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.
| | - Jennifer M Empey
- 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.
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
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Kohl FR, Grieco C, Kohler B. Ultrafast spectral hole burning reveals the distinct chromophores in eumelanin and their common photoresponse. Chem Sci 2019; 11:1248-1259. [PMID: 34123249 PMCID: PMC8148383 DOI: 10.1039/c9sc04527a] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Eumelanin, the brown-black pigment found in organisms from bacteria to humans, dissipates solar energy and prevents photochemical damage. While the structure of eumelanin is unclear, it is thought to consist of an extremely heterogeneous collection of chromophores that absorb from the UV to the infrared, additively producing its remarkably broad absorption spectrum. However, the chromophores responsible for absorption by eumelanin and their excited state decay pathways remain highly uncertain. Using femtosecond broadband transient absorption spectroscopy, we address the excited state behavior of chromophore subsets that make up a synthetic eumelanin, DOPA melanin, and probe the heterogeneity of its chromophores. Tuning the excitation light over more than an octave from the UV to the visible and probing with the broadest spectral window used to study any form of melanin to date enable the detection of spectral holes with a linewidth of 0.6 eV that track the excitation wavelength. Transient spectral hole burning is a manifestation of extreme chemical heterogeneity, yet exciting these diverse chromophores unexpectedly produces a common photoinduced absorption spectrum and similar kinetics. This common photoresponse is assigned to the ultrafast formation of immobile charge transfer excitons that decay locally and that are formed among graphene-like chromophores in less than 200 fs. Raman spectroscopy reveals that chromophore heterogeneity in DOPA melanin arises from different sized domains of sp2-hybridized carbon and nitrogen atoms. Furthermore, we identify for the first time striking parallels between the excited state dynamics of eumelanin and disordered carbon nanomaterials, suggesting that they share common structural attributes. Seeing the colors in black: ultrafast transient hole burning spectroscopy reveals the absorption properties of discrete chromophores and their interactions in the skin pigment eumelanin.![]()
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Affiliation(s)
- Forrest R Kohl
- Department of Chemistry and Biochemistry, The Ohio State University 100 West 18th Avenue Columbus Ohio 43210 USA +1-614-688-2635
| | - Christopher Grieco
- Department of Chemistry and Biochemistry, The Ohio State University 100 West 18th Avenue Columbus Ohio 43210 USA +1-614-688-2635
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University 100 West 18th Avenue Columbus Ohio 43210 USA +1-614-688-2635
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Li W, Wang Z, Xiao M, Miyoshi T, Yang X, Hu Z, Liu C, Chuang SSC, Shawkey MD, Gianneschi NC, Dhinojwala A. Mechanism of UVA Degradation of Synthetic Eumelanin. Biomacromolecules 2019; 20:4593-4601. [DOI: 10.1021/acs.biomac.9b01433] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Weiyao Li
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Zhao Wang
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Toshikazu Miyoshi
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Xiaozhou Yang
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | | | - Cheng Liu
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Steven S. C. Chuang
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Matthew D. Shawkey
- Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, Ledeganckstraat 35, Ghent 9000, Belgium
| | - Nathan C. Gianneschi
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
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Chang XP, Fang YG, Cui G. QM/MM Studies on the Photophysical Mechanism of a Truncated Octocrylene Model. J Phys Chem A 2019; 123:8823-8831. [PMID: 31550143 DOI: 10.1021/acs.jpca.9b07280] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Methyl 2-cyano-3,3-diphenylacrylate (MCDPA) shares the same molecular skeleton with octocrylene (OCR) that is one of the most common molecules used in commercially available sunscreens. However, its excited-state relaxation mechanism is unclear. Herein, we have used the QM(CASPT2//CASSCF)/MM method to explore spectroscopic properties, geometric and electronic structures, relevant conical intersections and crossing points, and excited-state relaxation paths of MCDPA in methanol solution. We found that in the Franck-Condon (FC) region, the V(1ππ*) state is energetically lower than the V'(1ππ*) state only by 2.8 kcal/mol and is assigned to experimentally observed maximum absorption band. From these two initially populated singlet states, there exist three nonradiative relaxation paths to repopulate the S0 state. In the first one, when the V(1ππ*) state is populated in the FC region, the system diabatically evolves along the V(1ππ*) state into its minimum where the internal conversion to S0 occurs. In the second one, the V'(1ππ*) state is populated in the FC region and the system adiabatically overcomes a barrier of ca. 3.0 kcal/mol to approach the V(1ππ*) minimum eventually leading to a V(1ππ*)-to-S0 internal conversion. In the third one, the V'(1ππ*) state first hops via the intersystem crossing to the T2 state, which then decays through the internal conversion to the T1 state. The T1 state is finally converted to the S0 state via the T1/S0 crossing point. Our present work contributes to understanding the photophysics of OCR and its variants.
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Affiliation(s)
- Xue-Ping Chang
- College of Chemistry and Chemical Engineering , Xinyang Normal University , Xinyang 464000 , P. R. China
| | - Ye-Guang Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , P. R. China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , P. R. China
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35
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Grieco C, Hanes AT, Blancafort L, Kohler B. Effects of Intra- and Intermolecular Hydrogen Bonding on O-H Bond Photodissociation Pathways of a Catechol Derivative. J Phys Chem A 2019; 123:5356-5366. [PMID: 31242734 DOI: 10.1021/acs.jpca.9b04573] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The catechol functional motif is thought to play both a structural and photochemical role in the ubiquitous natural pigment, eumelanin. Intramolecular and intermolecular hydrogen bonding interactions lead to a variety of geometries involving the two O-H groups in catechol, but its photophysical behavior in these situations has not been comprehensively characterized. Toward this end, we monitor the UV-induced O-H bond photodissociation reaction in an exemplar catechol derivative, 4- tert-butylcatechol, possessing different intramolecular and intermolecular hydrogen bonding geometries using femtosecond transient absorption spectroscopy measurements in the UV-visible and mid-infrared regions following 265 nm photoexcitation. Three different hydrogen bonding arrangements are obtained by tuning solution complexation equilibria of the catechol with the hydrogen bond acceptor, diethyl ether (Et2O), and are verified computationally. We find that intermolecular hydrogen bonding to the free O-H group in catechol increases its first excited singlet state (S1) lifetime by 2 orders of magnitude (i.e., ∼ 16 to 1410 ps), and that O-H bond dissociation is prevented because Et2O is a poor hydrogen atom acceptor. Complexation of both O-H groups with multiple Et2O molecules further elongates the S1 lifetime to 1670 ps due to shifting of the solution equilibria that describe complex formation. Weakening of the characteristic, intramolecular hydrogen bond of the catechol derivative by intermolecular hydrogen bonding to one or more Et2O molecules does not enhance the rate of O-H bond dissociation.
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Affiliation(s)
- Christopher Grieco
- Department of Chemistry and Biochemistry , The Ohio State University , 100 West 18th Avenue , Columbus , Ohio 43210 , United States
| | - Alex T Hanes
- Department of Chemistry and Biochemistry , The Ohio State University , 100 West 18th Avenue , Columbus , Ohio 43210 , United States
| | - Lluís Blancafort
- Institut de Química Computacional i Catàlisi and Departament de Química, Facultat de Ciències , Universitat de Girona , C/M.A. Capmany 69 , 17003 Girona , Spain
| | - Bern Kohler
- Department of Chemistry and Biochemistry , The Ohio State University , 100 West 18th Avenue , Columbus , Ohio 43210 , United States
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36
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Xiao M, Chen W, Li W, Zhao J, Hong YL, Nishiyama Y, Miyoshi T, Shawkey MD, Dhinojwala A. Elucidation of the hierarchical structure of natural eumelanins. J R Soc Interface 2019. [PMID: 29514988 DOI: 10.1098/rsif.2018.0045] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Eumelanin is one of the most ubiquitous pigments in living organisms and plays an important role in coloration and UV protection. Because eumelanin is highly cross-linked and insoluble in solvents, the chemical structure is still not completely known. In this study, we used atomic force microscopy, X-ray photoelectron spectroscopy and solid-state nuclear magnetic resonance (NMR) to compare intact eumelanosomes (pigment granules mostly made of eumelanin) from four phylogentically distant species: cuttlefish (Sepia officinalis) inks, black fish crow (Corvus ossifragus) feathers, iridescent wild turkey (Melleagris gallopavo) feathers and black human hair. We found that eumelanosomes from all four species are composed of subunit nanoparticles with a length of 10-60 nm, consistent with earlier observations in eumelanosomes from the sepia ink and human hair. The solid-state NMR results indicate the presence of quinone methide tautomers in all four eumelanins. We also found clear differences in the UV absorbance, the ratio of 5,6-dihydroxyindole-2-carboxylic acid/5,6-dihydroxyindole and protonated aryl carbon ratios in sepia eumelanin relative to the other three. This comparison of natural eumelanin across a phylogenetically broad group of organisms provides insights into the change in the eumelanin structure over the evolutionary history and enables the production of synthetic eumelanin with properties that are similar to natural eumelanin.
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Affiliation(s)
- Ming Xiao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Wei Chen
- State Key Lab of Pollution Control and Resource Reuse Study, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Weiyao Li
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Jiuzhou Zhao
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - You-Lee Hong
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.,RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama 230-0045, Japan
| | - Yusuke Nishiyama
- RIKEN CLST-JEOL Collaboration Center, RIKEN, Yokohama 230-0045, Japan.,JEOL RESONANCE Inc., Tokyo 196-8558, Japan
| | - Toshikazu Miyoshi
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent, Ghent 9000, Belgium
| | - Ali Dhinojwala
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA
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37
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Silver-nanoparticles as plasmon-resonant enhancers for eumelanin's photoacoustic signal in a self-structured hybrid nanoprobe. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 102:788-797. [PMID: 31147051 DOI: 10.1016/j.msec.2019.04.066] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/03/2019] [Accepted: 04/21/2019] [Indexed: 11/20/2022]
Abstract
Developing safe and high efficiency contrast tools is an urgent need to allow in vivo applications of photoacoustics (PA), an emerging biomolecular imaging methodology, with poor invasiveness, deep penetration, high spatial resolution and excellent endogenous contrast. Eumelanins hold huge promise as biocompatible, endogenous photoacoustic contrast agents. However, their huge potential is still unexplored due to the difficulty to achieve at the same time poor aggregation in physiologic environment and high PA contrast. This study addresses both issues through the design of a biocompatible photoacoustic nanoprobe, named MelaSil_Ag-NPs, relying on silica-templated eumelanin formation as well as eumelanins redox and metal chelating properties to reduce Ag+ ions and control the growth of generated metal nanoparticles. This strategy allowed self-structuring of the system into a core-shell architecture, where the Ag core was found to boost PA signal, despite the poor eumelanin content. Obtained hybrid nanoplatforms, showed stable photoacoustic properties even under long irradiation. Furthermore, conjugation with rhodamine isothiocyanate allowed particles detection through fluorescent imaging proving their multifunctional potentialities. In addition, they were stable towards aggregation and efficiently endocytosed by human pancreatic cancer cells (BxPC3 and Panc-1) displaying no significant cytotoxicity. Such numerous features prove huge potential of those nanoparticles as a multifunctional platform for biomedical applications.
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38
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Crane SW, Ghafur O, Cowie TY, Lindsay AG, Thompson JOF, Greenwood JB, Bebbington MWP, Townsend D. Dynamics of electronically excited states in the eumelanin building block 5,6-dihydroxyindole. Phys Chem Chem Phys 2019; 21:8152-8160. [PMID: 30933211 DOI: 10.1039/c9cp00620f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the first excited state dynamics study of gas-phase 5,6-dihydroxyindole (5,6-DHI), a key building block of eumelanin pigments that are found throughout nature and serve as important photo-protective compounds. Time-resolved ion-yield measurements over the 241-296 nm ultraviolet photoexcitation region revealed non-adiabatic processes occurring on up to three distinct timescales. These reflect ultrafast (i.e. sub-picosecond) internal conversion within the excited state singlet manifold, and much longer-lived processes ranging from 10 ps to in excess of 1 ns. Our investigation paves the way for precisely targeted future studies of 5,6-DHI that exploit more differential measurement techniques. The work was facilitated by the use of soft laser-based thermal desorption to introduce 5,6-DHI samples into the gas phase. This approach, based on low-cost, readily available diode lasers, is straightforward, easily controllable and potentially applicable to a wide range of non-volatile molecular species.
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Affiliation(s)
- Stuart W Crane
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
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De Marchi F, Galeotti G, Simenas M, Ji P, Chi L, Tornau EE, Pezzella A, MacLeod J, Ebrahimi M, Rosei F. Self-assembly of 5,6-dihydroxyindole-2-carboxylic acid: polymorphism of a eumelanin building block on Au(111). NANOSCALE 2019; 11:5422-5428. [PMID: 30855042 DOI: 10.1039/c8nr09810g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Investigating two-dimensional (2D) self-assembled structures of biological monomers governed by intermolecular interactions is a prerequisite to understand the self-assembly of more complex biomolecular systems. 5,6-Dihydroxyindole carboxylic acid (DHICA) is one of the building blocks of eumelanin - an irregular heteropolymer and the most common form of melanin which has potential applications in organic electronics and bioelectronics. By means of scanning tunneling microscopy, density functional theory and Monte Carlo calculations, we investigate DHICA molecular configurations and interactions underlying the multiple 2D patterns formed on Au(111). While DHICA self-assembled molecular networks (SAMNs) are dominated by the hydrogen bonding of carboxylic acid dimers, a variety of 2D architectures are formed due to the multiple weak interactions of the catechol group. The hydroxyl group also allows for redox reactions, caused by oxidation via O2 exposure, resulting in molecular rearrangement. The susceptibility of the molecules to oxidation is affected by their SAMNs architectures, giving insights on the reactivity of indoles as well as highlighting non-covalent assembly as an approach to guide selective oxidation reactions.
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Affiliation(s)
- F De Marchi
- Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC, Canada J3X 1S2.
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40
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Intermolecular association of some selected melanin monomers and their optical absorption. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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41
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D'Alba L, Shawkey MD. Melanosomes: Biogenesis, Properties, and Evolution of an Ancient Organelle. Physiol Rev 2019; 99:1-19. [PMID: 30255724 DOI: 10.1152/physrev.00059.2017] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Melanosomes are organelles that produce and store melanin, a widespread biological pigment with a unique suite of properties including high refractive index, semiconducting capabilities, material stiffness, and high fossilization potential. They are involved in numerous critical biological functions in organisms across the tree of life. Individual components such as melanin chemistry and melanosome development have recently been addressed, but a broad synthesis is needed. Here, we review the hierarchical structure, development, functions, and evolution of melanosomes. We highlight variation in melanin chemistry and melanosome morphology and how these may relate to function. For example, we review what is known of the chemical differences between different melanin types (eumelanin, pheomelanin, allomelanin) and whether/how melanosome morphology relates to chemistry and color. We integrate the distribution of melanin across living organisms with what is known from the fossil record and produce hypotheses on its evolution. We suggest that melanin was present in life forms early in evolutionary history and that melanosomes evolved at the origin of organelles. Throughout, we discuss the (sometimes gaping) holes in our knowledge and suggest areas that need particular attention as we move forward in our understanding of these still-mysterious organelles and the materials that they contain.
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Affiliation(s)
- Liliana D'Alba
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent , Ghent , Belgium
| | - Matthew D Shawkey
- Evolution and Optics of Nanostructures Group, Department of Biology, University of Ghent , Ghent , Belgium
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42
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Le NTK, Kang K. Functional Amyloid as a Potential Encoder of Melanin Pigments. B KOREAN CHEM SOC 2019. [DOI: 10.1002/bkcs.11652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nghia T. K. Le
- Department of Applied ChemistryKyung Hee University Yongin 17104 South Korea
| | - Kyungtae Kang
- Department of Applied ChemistryKyung Hee University Yongin 17104 South Korea
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43
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Eckert S, Norell J, Jay RM, Fondell M, Mitzner R, Odelius M, Föhlisch A. T 1 Population as the Driver of Excited-State Proton-Transfer in 2-Thiopyridone. Chemistry 2019; 25:1733-1739. [PMID: 30452789 PMCID: PMC6470867 DOI: 10.1002/chem.201804166] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Indexed: 01/02/2023]
Abstract
Excited-state proton transfer (ESPT) is a fundamental process in biomolecular photochemistry, but its underlying mediators often evade direct observation. We identify a distinct pathway for ESPT in aqueous 2-thiopyridone, by employing transient N 1s X-ray absorption spectroscopy and multi-configurational spectrum simulations. Photoexcitations to the singlet S2 and S4 states both relax promptly through intersystem crossing to the triplet T1 state. The T1 state, through its rapid population and near nanosecond lifetime, mediates nitrogen site deprotonation by ESPT in a secondary intersystem crossing to the S0 potential energy surface. This conclusively establishes a dominant ESPT pathway for the system in aqueous solution, which is also compatible with previous measurements in acetonitrile. Thereby, the hitherto open questions of the pathway for ESPT in the compound, including its possible dependence on excitation wavelength and choice of solvent, are resolved.
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Affiliation(s)
- Sebastian Eckert
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Straße 24/25, 14476, Potsdam, Germany
| | - Jesper Norell
- Department of Physics, Stockholm University, AlbaNova University Centre, 10691, Stockholm, Sweden
| | - Raphael M Jay
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Straße 24/25, 14476, Potsdam, Germany
| | - Mattis Fondell
- Institute for Methods and Instrumentation for, Synchrotron Radiation Research, Helmholtz-Zentrum für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Rolf Mitzner
- Institute for Methods and Instrumentation for, Synchrotron Radiation Research, Helmholtz-Zentrum für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Michael Odelius
- Department of Physics, Stockholm University, AlbaNova University Centre, 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 für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489, Berlin, Germany
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44
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Zhang P, Li S, Fu C, Zhang Q, Xiao Y, Ding C. A colorimetric and near -infrared ratiometric fluorescent probe for the determination of endogenous tyrosinase activity based on cyanine aggregation. Analyst 2019; 144:5472-5478. [DOI: 10.1039/c9an01045a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A ratiometric fluorescent probe for TYR activity with high sensitivity was developed based on the H-aggregation of a cyanine dye.
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Affiliation(s)
- Peng Zhang
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
| | - Shasha Li
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
| | - Caixia Fu
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
| | - Qian Zhang
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
| | - Yuzhe Xiao
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
| | - Caifeng Ding
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science
- MOE; Shandong Key Laboratory of Biochemical Analysis; Key Laboratory of Analytical Chemistry for Life Science in Universities of Shandong; College of Chemistry and Molecular Engineering. Qingdao University of Science and Technology
- Qingdao 266042
- PR China
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45
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Ghosh P, Ghosh D. Non-radiative decay of an eumelanin monomer: to be or not to be planar. Phys Chem Chem Phys 2019; 21:6635-6642. [DOI: 10.1039/c9cp00246d] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The planar and nonplanar non-radiative decay channels of eumelanin monomer.
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Affiliation(s)
- Paulami Ghosh
- School of Mathematical and Computational Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Debashree Ghosh
- School of Mathematical and Computational Sciences
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
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46
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Grieco C, Kohl FR, Zhang Y, Natarajan S, Blancafort L, Kohler B. Intermolecular Hydrogen Bonding Modulates O-H Photodissociation in Molecular Aggregates of a Catechol Derivative. Photochem Photobiol 2018; 95:163-175. [PMID: 30317633 DOI: 10.1111/php.13035] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 10/01/2018] [Indexed: 01/15/2023]
Abstract
The catechol functional group plays a major role in the chemistry of a wide variety of molecules important in biology and technology. In eumelanin, intermolecular hydrogen bonding between these functional groups is thought to contribute to UV photoprotective and radical buffering properties, but the mechanisms are poorly understood. Here, aggregates of 4-t-butylcatechol are used as model systems to study how intermolecular hydrogen bonding influences photochemical pathways that may occur in eumelanin. Ultrafast UV-visible and mid-IR transient absorption measurements are used to identify the photochemical processes of 4-t-butylcatechol monomers and their hydrogen-bonded aggregates in cyclohexane solution. Monomer photoexcitation results in hydrogen atom ejection to the solvent via homolytic O-H bond dissociation with a time constant of 12 ps, producing a neutral semiquinone radical with a lifetime greater than 1 ns. In contrast, intermolecular hydrogen bonding interactions within aggregates retard O-H bond photodissociation by over an order of magnitude in time. Excited state structural relaxation is proposed to slow O-H dissociation, allowing internal conversion to the ground state to occur in hundreds of picoseconds in competition with this channel. The semiquinone radicals formed in the aggregates exhibit spectral broadening of both their electronic and vibrational transitions.
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Affiliation(s)
- Christopher Grieco
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH
| | - Forrest R Kohl
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH
| | - Yuyuan Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH
| | - Sangeetha Natarajan
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH
| | - Lluís Blancafort
- Institut de Química Computacional i Catàlisi and Departament de Química, Facultat de Ciències, Universitat de Girona, Girona, Spain
| | - Bern Kohler
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH
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47
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De Marchi F, Galeotti G, Simenas M, Tornau EE, Pezzella A, MacLeod J, Ebrahimi M, Rosei F. Room-temperature surface-assisted reactivity of a melanin precursor: silver metal-organic coordination versus covalent dimerization on gold. NANOSCALE 2018; 10:16721-16729. [PMID: 30156253 DOI: 10.1039/c8nr04002h] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The ability of catecholamines to undergo oxidative self-polymerization provides an attractive route for preparation of coatings for biotechnology and biomedicine applications. However, efforts toward developing a complete understanding of the mechanism that underpins polymerization have been hindered by the multiple catechol crosslinking reaction pathways that occur during the reaction. Scanning tunneling microscopy allows the investigation of small molecules in a reduced-complexity environment, providing important insight into how the intermolecular forces drive the formation of supramolecular assemblies in a controlled setting. Capitalizing on this approach, we studied the self-assembly of 5,6-dihydroxy-indole (DHI) on Au(111) and Ag(111) to investigate the interactions that affect the two-dimensional growth mechanism and to elucidate the behavior of the catechol group on these two surfaces. X-ray photoelectron spectroscopy, together with density functional theory and Monte Carlo modeling, helps unravel the differences between the two systems. The molecules form large ordered domains, yet with completely different architectures. Our data reveal that some of the DHI molecules deposited on Ag are in a modified redox state, with their catechol group oxidized into quinone. On Ag(111), the molecules are deposited in long-range lamellar patterns stabilized by metal-organic coordination, while covalent dimer pairs are observed on Au(111). We also show that the oxidation susceptibility is affected by the substrate, with the DHI/Au remaining inert even after being exposed to O2 gas.
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Affiliation(s)
- F De Marchi
- Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Boulevard Lionel-Boulet, Varennes, QC, Canada J3X 1S2.
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48
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Bergtold C, Hauser D, Chaumont A, El Yakhlifi S, Mateescu M, Meyer F, Metz-Boutigue MH, Frisch B, Schaaf P, Ihiawakrim D, Ersen O, Monnier CA, Petri-Fink A, Rothen-Rutishauser B, Ball V. Mimicking the Chemistry of Natural Eumelanin Synthesis: The KE Sequence in Polypeptides and in Proteins Allows for a Specific Control of Nanosized Functional Polydopamine Formation. Biomacromolecules 2018; 19:3693-3704. [DOI: 10.1021/acs.biomac.8b00818] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Camille Bergtold
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
- Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - Daniel Hauser
- Adolphe Merkle Institute, University of Fribourg, 4 Chemin des Verdiers, CH-1700 Fribourg, Switzerland
| | - Alain Chaumont
- Faculté de Chimie, Chimie de la Matière Complexe, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7140, 4 rue Blaise Pascal, 67081, Strasbourg, France
| | - Salima El Yakhlifi
- Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - Mihaela Mateescu
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
| | - Florent Meyer
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
- Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - Marie-Hélène Metz-Boutigue
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
- Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France
| | - Benoît Frisch
- Université de Strasbourg, Faculté de Pharmacie, Laboratoire de Conception et application de molécules bioactives, 74 Route du Rhin, 67400 Illkirch-Graffenstaden, France
| | - Pierre Schaaf
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
- Centre National de la Recherche Scientifique, Institut Charles Sadron, Unité Propre 22, 23 rue du Loess, 67034 Strasbourg, France
| | - Dris Ihiawakrim
- Centre National de la Recherche Scientifique, Institut de Physique et de Chimie des Matériaux, Unité Mixte de Recherche 7504, 23 rue du Loess, 67034, Strasbourg, Cedex 2, France
| | - Ovidiu Ersen
- Centre National de la Recherche Scientifique, Institut de Physique et de Chimie des Matériaux, Unité Mixte de Recherche 7504, 23 rue du Loess, 67034, Strasbourg, Cedex 2, France
| | - Christophe A. Monnier
- Adolphe Merkle Institute, University of Fribourg, 4 Chemin des Verdiers, CH-1700 Fribourg, Switzerland
| | - Alke Petri-Fink
- Adolphe Merkle Institute, University of Fribourg, 4 Chemin des Verdiers, CH-1700 Fribourg, Switzerland
| | | | - Vincent Ball
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg France
- Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche 1121, 11 rue Humann, 67085 Strasbourg Cedex, France
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49
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Peng M, Wang Y, Fu Q, Sun F, Na N, Ouyang J. Melanosome-Targeting Near-Infrared Fluorescent Probe with Large Stokes Shift for in Situ Quantification of Tyrosinase Activity and Assessing Drug Effects on Differently Invasive Melanoma Cells. Anal Chem 2018; 90:6206-6213. [PMID: 29696968 DOI: 10.1021/acs.analchem.8b00734] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tyrosinase (TYR) plays a vital role in melanin biosynthesis and is widely regarded as a relatively specific marker for melanocytic lesions which involve vitiligo, malignant cutaneous melanoma, Parkinson's disease (PD), etc. However, the detection of TYR in living cells with fluorescent probes is usually interfered by diverse endogenous reactive oxygen species (ROS) and reactive nitrogen species (RNS). Herein, we synthesized a melanosome-targeting near-infrared (NIR) fluorescent probe (HB-NP) with a large Stokes shift (195 nm), achieving a highly sensitive and selective in situ detection for intracellular TYR, by incorporating a m-hydroxybenzyl moiety that recognizes TYR specifically and the morpholine unit which facilitates the probe accumulating in the melanosome into a salicyladazine skeleton. When treated with TYR, the probe itself with weak fluorescence is lit up via an inhibited photoinduced electron-transfer (PET) effect and HB-NP shows a strong fluorescence signal (nearly 48-fold enhancement) with a low detection limit of 0.5 U mL-1. HB-NP has been successfully applied in visualizing and in situ quantification of the intracellular TYR activity. Moreover, owing to the different expression levels of TYR, two human uveal melanoma cells with different invasive behaviors are distinguished by means of bioimaging and the effects of the inhibitor, kojic acid, and the up-regulating treatment, psoralen/ultraviolet A, on TYR activity of the two melanoma cells are evaluated. HB-NP is expected to be a useful tool to monitor diseases associated with the abnormal level of melanin and screen medicines for TYR disorder more effectively.
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Affiliation(s)
- Manshu Peng
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
| | - Yan Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
| | - Qiang Fu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
| | - Feifei Sun
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
| | - Na Na
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
| | - Jin Ouyang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry , Beijing Normal University , Beijing 100875 , China
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50
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Baker LA, Marchetti B, Karsili TNV, Stavros VG, Ashfold MNR. Photoprotection: extending lessons learned from studying natural sunscreens to the design of artificial sunscreen constituents. Chem Soc Rev 2018; 46:3770-3791. [PMID: 28580469 DOI: 10.1039/c7cs00102a] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Evolution has ensured that plants and animals have developed effective protection mechanisms against the potentially harmful effects of incident ultraviolet radiation (UVR). Tanning is one such mechanism in humans, but tanning only occurs post-exposure to UVR. Hence, there is ever growing use of commercial sunscreens to pre-empt overexposure to UVR. Key requirements for any chemical filter molecule used in such a photoprotective capacity include a large absorption cross-section in the UV-A and UV-B spectral regions and the availability of one or more mechanisms whereby the absorbed photon energy can be dissipated without loss of the molecular integrity of the chemical filter. Here we summarise recent experimental (mostly ultrafast pump-probe spectroscopy studies) and computational progress towards unravelling various excited state decay mechanisms that afford the necessary photostability in chemical filters found in nature and those used in commercial sunscreens. We also outline ways in which a better understanding of the photophysics and photochemistry of sunscreen molecules selected by nature could aid the design of new and improved commercial sunscreen formulations.
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Affiliation(s)
- Lewis A Baker
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Barbara Marchetti
- Department of Chemistry, University of Pennsylvania, Philadelphia, USA
| | | | - Vasilios G Stavros
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
| | - Michael N R Ashfold
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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