1
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Ye F, Chen W, Deng Z, Chen SL, Dong Z, Dang L, Li MD. Ultrafast excited-state energy dissipation pathway of diethylamino hydroxybenzoyl hexyl benzoate (DHHB) via the nanoparticles. Photochem Photobiol Sci 2023; 22:2133-2142. [PMID: 37195390 DOI: 10.1007/s43630-023-00435-z] [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: 12/17/2022] [Accepted: 05/03/2023] [Indexed: 05/18/2023]
Abstract
The organic UVA filter is popularized in sunscreen cosmetics due to the advantages of excellent light stability and high molar extinction coefficient. However, the poor water solubility of organic UV filters has been a common problem. Given that nanoparticles (NPs) can significantly improve the water solubility of organic chemicals. Meanwhile, the excited-state relaxation pathways of NPs might differ from their solution. Here, the NPs of diethylamino hydroxybenzoyl hexyl benzoate (DHHB), a popular organic UVA filter, were prepared by an advanced ultrasonic micro-flow reactor. The surfactant (sodium dodecyl sulfate) was selected as an effective stabilizer to prevent the self-aggregation of the NPs for DHHB. Femtosecond transient ultrafast spectroscopy (fs-TA) and theoretical calculations were utilized to trace and explain the excited-state evolution of DHHB in NPs suspension and its solution. The results reveal that the surfactant-stabilized NPs of DHHB reserve a similarly good performance of ultrafast excited-state relaxation. The stability characterization experiments demonstrate that the strategy of surfactant-stabilized NPs for sunscreen chemicals can maintain its stability and enhance the water solubility of DHHB compared with that of the solution phase. Therefore, the surfactant-stabilized NPs of organic UV filters are an effective method to improve water solubility and keep the stability from aggregation and photoexcitation.
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Affiliation(s)
- Fanwei Ye
- College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, No 243, University Road, Shantou, 515063, China
| | - Wenbin Chen
- College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, No 243, University Road, Shantou, 515063, China
| | - Ziqi Deng
- Department of Chemistry, the University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Shun-Li Chen
- College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, No 243, University Road, Shantou, 515063, China
| | - Zhengya Dong
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China
| | - Li Dang
- College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, No 243, University Road, Shantou, 515063, China.
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China.
| | - Ming-De Li
- College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, No 243, University Road, Shantou, 515063, China.
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou, 515031, China.
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2
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Cowden AM, Whittock AL, Holt EL, Stavros VG, Wills M. Synthesis and characterisation of novel composite sunscreens containing both avobenzone and octocrylene motifs. RSC Adv 2023; 13:17017-17027. [PMID: 37293474 PMCID: PMC10245224 DOI: 10.1039/d3ra02252h] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/29/2023] [Indexed: 06/10/2023] Open
Abstract
Avobenzone and octocrylene are popular sunscreen active ingredients. Experiments that probe the stability of avobenzone in binary mixtures with octocrylene are presented, together with the synthesis of a class of novel composite sunscreens that were designed by covalently linking avobenzone and octocrylene groups. Spectroscopy, both steady-state and time-resolved, of the fused molecules was performed to investigate the stability of the new molecules and their potential function as ultraviolet filters. Computational results are detailed for truncated versions of a subset of the molecules to reveal the energy states underlying the absorption processes of this new class of sunscreen. The results indicate that the combination of elements of the two sunscreen molecules into one molecule creates a derivative with good stability to UV light in ethanol and in which the main degradation pathway of the avobenzone component in acetonitrile is reduced. Derivatives containing p-chloro substituents are particularly stable to UV light.
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Affiliation(s)
- Adam M Cowden
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Molecular Analytical Science Centre for Doctoral Training, Senate House, University of Warwick Coventry CV4 7AL UK
| | - Abigail L Whittock
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
- Analytical Science Centre for Doctoral Training, Senate House, University of Warwick Coventry CV4 7AL UK
| | - Emily L Holt
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | | | - Martin Wills
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
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3
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Li Y, He Y, Lam CH, Nah T. Environmental photochemistry of organic UV filter butyl methoxydibenzoylmethane: Implications for photochemical fate in surface waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 839:156145. [PMID: 35613640 DOI: 10.1016/j.scitotenv.2022.156145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 05/16/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
With the widespread use of sunscreen and other personal care products, organic ultraviolet filters (OUVFs) have become widely detected in the aquatic environment. Direct and indirect photolysis are important transformation pathways of OUVFs in aquatic environments, so their transformation products (TPs) are also chemicals of concern. Butyl methoxydibenzoylmethane (BMDBM) is one of the most commonly used OUVFs worldwide due to its ability to absorb ultraviolet light across a wide range of wavelengths, and it is ubiquitously detected in aquatic environments. In this study, we investigated the photodegradation of BMDBM through direct photolysis and hydroxyl radical (•OH) photooxidation. TPs were identified using ultrahigh performance liquid chromatography-high resolution mass spectrometry, and reaction mechanisms were proposed. Our results showed that the photodegradation rates for both enol and keto tautomer forms of BMDBM during direct photolysis and •OH photooxidation were similar. The formation of TPs resulted from α-cleavage and decarbonylation reactions involving the keto form of BMDBM. Comparisons of the kinetic data and TPs revealed that the direct photolysis mechanism was a significant sink for BMDBM even during •OH photooxidation. Evaluations of environmental properties based on the predicted physicochemical properties of BMDBM and TPs suggests that some of the TPs will have higher mobility than BMDBM. The quantitative structure-activity relationship (QSAR) approach was used to evaluate the ecotoxicity of BMDBM and the identified TPs. Most TPs were found to be less ecotoxic than BMDBM; however, TPs that had a diphenyl ring structure could be more ecotoxic than BMDBM. Overall, this study provides new insights into the photochemical behavior and ecotoxicity of BMDBM and its TPs, which are important for assessing the fate, persistence, accumulation, and adverse impacts of these compounds in aquatic environments.
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Affiliation(s)
- Yitao Li
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
| | - Yuhe He
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
| | - Chun Ho Lam
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
| | - Theodora Nah
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
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4
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Moi S, Shekh S, Reddy KKA, Dhurjad P, Sonti R, Gowd KH. Peptide Cysteine Thiols Act as Photostabilizer of Avobenzone through Stabilising the Transition State of Keto-enol Tautomerization. Photochem Photobiol 2022; 99:911-919. [PMID: 35975619 DOI: 10.1111/php.13691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/13/2022] [Indexed: 11/28/2022]
Abstract
Photostabilizers have been used to impart stability to an FDA-approved chemical UV-A filter avobenzone against the UV-A radiations and sunlight. The thiol group of glutathione plays a critical role in imparting the photostabilization activity of glutathione on avobenzone. The current report aims to evaluate the photostabilization activity of multiple thiols containing cysteine peptides on avobenzone. Cysteine-tripeptide and cysteine-pentapeptide were chemically synthesized and characterized using mass spectrometry. Synthetic peptides were assessed for their photostabilization activity on the enolic-form of the avobenzone under natural sunlight using UV-spectroscopy in both protic and aprotic solvents. Unlike glutathione which has pronounced activity in protic solvents, cysteine-pentapeptide exhibits similar photoprotection activity in both protic and aprotic solvents. Computational calculations using DFT suggest that peptide cysteine thiols may assist in the reversal of the photoketonization process of avobenzone thereby exhibiting the photoprotection activity to the enolic-form of avobenzone. Peptide cysteine thiols lower the activation energy barrier of keto-to-enol tautomerization of avobenzone by 30 kcal/mol by assisting the proton shuttle through a six-membered transition state. The current report emphasizes the applications of peptide thiols in cosmetics and may help in the development of peptides as aesthetic medicines.
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Affiliation(s)
- Smriti Moi
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, 585367, Karnataka, India
| | - Shamasoddin Shekh
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, 585367, Karnataka, India
| | - K Kasi Amarnath Reddy
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, 585367, Karnataka, India
| | - Pooja Dhurjad
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500037, Telangana, India
| | - Rajesh Sonti
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500037, Telangana, India
| | - Konkallu Hanumae Gowd
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, 585367, Karnataka, India
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5
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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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6
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Fan J, Finazzi L, Jan Buma W. Elucidating the photoprotective properties of natural UV screening agents: ZEKE-PFI spectroscopy of methyl sinapate. Phys Chem Chem Phys 2022; 24:3984-3993. [PMID: 35099484 DOI: 10.1039/d1cp05958k] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
As a prominent derivative of a natural sunscreen, methyl sinapate is an ideal candidate to provide fundamental insight into strategies on how to come to a rational design of artificial sunscreen filters with improved photoprotective properties. Here, static and time-resolved Zero Kinetic Energy-Pulsed Field Ionization (ZEKE-PFI) photoelectron spectroscopy has been used to study the spectroscopy and decay pathways of its electronically excited states. We find that different conformers are subject to distinct structural changes upon electronic excitation, and trace the structural changes that occur upon excitation back to the character of the LUMO. Ionization efficiency spectra in combination with pump-probe ZEKE-PFI spectra are consistent with the conclusion that the long-lived electronically excited state observed in the decay of the lowest excited singlet state is the lowest excited triplet state. Concurrently with providing information on the electronically excited states, the studies allow for a detailed characterization of the spectroscopic properties of the ground state of the radical ion, which is important in the context of the use of cinnamates in nature as antioxidants. Our studies determine the adiabatic ionization energies of the syn/cis, anti/cis and anti/trans conformers as 60 291.1 ± 0.5, 60 366.9 ± 0.5 and 60 503.9 ± 1.0 cm-1, respectively, and provide accurate vibrational fequencies of low-frequency modes of the molecular ion in its electronic ground state. Finally, the studies emphasize the important role of vibrational and electronic autoionization processes that start to dominate the ionization dynamics in non-rigid molecules of the present size.
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Affiliation(s)
- Jiayun Fan
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
| | - Laura Finazzi
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
| | - Wybren Jan Buma
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands. .,Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7c, 6525 ED Nijmegen, The Netherlands
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7
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Chang XP, Zhang TS, Cui G. Theoretical Studies on the Excited-State Decay Mechanism of Homomenthyl Salicylate in a Gas Phase and an Acetonitrile Solution. J Phys Chem A 2021; 126:16-28. [PMID: 34963284 DOI: 10.1021/acs.jpca.1c07108] [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
Here, we employ the CASPT2//CASSCF and QM(CASPT2//CASSCF)/MM approaches to explore the photochemical mechanism of homomenthyl salicylate (HMS) in vacuum and an acetonitrile solution. The results show that in both cases, the excited-state relaxation mainly involves a spectroscopically "bright" S1(1ππ*) state and the lower-lying T1 and T2 states. In the major relaxation pathway, the photoexcited S1 keto system first undergoes an essentially barrierless excited-state intramolecular proton transfer (ESIPT) to generate the S1 enol minimum, near which a favorable S1/S0 conical intersection decays the system to the S0 state followed by a reverse ground-state intramolecular proton transfer (GSIPT) to repopulate the initial S0 keto species. In the minor one, an S1/T2/T1 three-state intersection in the keto region makes the T1 state populated via direct and T2-mediated intersystem crossing (ISC) processes. In the T1 state, an ESIPT occurs, which is followed by ISC near a T1/S0 crossing point in the enol region to the S0 state and finally back to the S0 keto species. In addition, a T1/S0 crossing point near the T1 keto minimum can also help the system decay to the S0 keto species. However, small spin-orbit couplings between T1 and S0 at these T1/S0 crossing points make ISC to the S0 state very slow and make the system trapped in the T1 state for a while. The present work rationalizes not only the ultrafast excited-state decay dynamics of HMS but also its low quantum yield of phosphorescence at 77 K.
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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
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, 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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8
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Holt EL, Rodrigues NDN, Cebrián J, Stavros VG. Determining the photostability of avobenzone in sunscreen formulation models using ultrafast spectroscopy. Phys Chem Chem Phys 2021; 23:24439-24448. [PMID: 34694312 DOI: 10.1039/d1cp03610f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Avobenzone is an ultraviolet (UV) filter that is often included in sunscreen formulations despite its lack of photostability. Its inclusion is necessary due to few existing alternatives for photoprotection in the UVA region (320-400 nm). To better understand and predict the photostability of avobenzone, ultrafast transient electronic absorption spectroscopy (TEAS) has been used to study the effects of solvent (including emollients), concentration and skin surface temperature on its excited-state relaxation mechanism, following photoexcitation with UVA radiation (∼350 nm). Subtle differences between the excited-state lifetimes were found between the systems, but the TEAS spectral features were qualitatively the same for all solution and temperature combinations. Alongside TEAS measurements, UV filter/emollient blends containing avobenzone were irradiated using simulated solar light and their degradation tracked using steady-state UV-visible spectroscopy. Sun protection factor (SPF) and UVA protection factor (UVA-PF) assessments were also carried out on representative oil phases (higher concentration blends), which could be used to formulate oil-in-water sunscreens. It was found that there was an apparent concentration dependence on the long-term photoprotective efficacy of these mixtures, which could be linked to the ultrafast photodynamics by the presence of a ground-state bleach offset. This combination of techniques shows potential for correlating long-term behaviours (minutes to hours) of avobenzone with its ultrafast photophysics (femtoseconds to nanoseconds), bridging the gap between fundamental photophysics/photochemistry and commercial sunscreen design.
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Affiliation(s)
- Emily L Holt
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK. .,Molecular Analytical Science Centre for Doctoral Training, Senate House, University of Warwick, Coventry, CV4 7AL, UK
| | - Natércia D N Rodrigues
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK. .,Lubrizol Life Science Beauty, Calle Isaac Peral, 17 Pol. Ind. Camí Ral, 08850 Barcelona, Spain
| | - Juan Cebrián
- Lubrizol Life Science Beauty, Calle Isaac Peral, 17 Pol. Ind. Camí Ral, 08850 Barcelona, Spain
| | - Vasilios G Stavros
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
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9
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Moi S, Hosamani B, Kumar K, Gunaga S, Raghothama S, Gowd KH. Photochemical studies of new synthetic derivatives of avobenzone under sunlight using UV-spectroscopy. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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10
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Herzog B, Giesinger J, Settels V. Insights into the stabilization of photolabile UV-absorbers in sunscreens. Photochem Photobiol Sci 2020; 19:1636-1649. [PMID: 33300922 DOI: 10.1039/d0pp00335b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Sunscreens are used to protect human skin against harmful UV radiation. Today there is a trend towards high sun protection factors (SPF) and good UVA protection. Methods for the assessment of SPF and UVA protection involve irradiation of the product, and the photostability properties of the sunscreen have an influence on its performance. Sunscreens often contain more than one UV filter. Some photolabile UV absorbers may be stabilized by the presence of other photostable UV-absorbers. Stabilization can be achieved just by a certain optical density due to the presence of such UV-filter substances. However, photostabilization may also be caused by quenching mechanisms, such as singlet-singlet or triplet-triplet energy transfer. Investigation of butyl methoxy dibenzoylmethane and ethylhexyl methoxycinnamate as photolabile sunscreens in the presence of either octocrylene or bis ethylhexyloxyphenol methoxyphenyl triazine showed that both mechanisms may apply. With the systems butyl methoxy dibenzoylmethane plus octocrylene and ethylhexyl methoxycinnamate plus bis ethylhexyloxyphenol methoxyphenyl triazine the quenching mechanism appears to be predominant.
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Affiliation(s)
- Bernd Herzog
- BASF Grenzach GmbH, Koechlinstrasse 1, 79639 Grenzach-Wyhlen, Germany.
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11
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Cao CN, Liu CF, Zhao L, Rao GW. New insight into the photoinduced wavelength dependent decay mechanisms of the ferulic acid system on the excited states. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 240:118565. [PMID: 32554260 DOI: 10.1016/j.saa.2020.118565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
The ferulic acid (FA) is a kind of phenolic acid widely exists in nature plants. Apart from its medicinal values, the FA is also widely applied in cosmetic industry. Recently, it was found to have potential applications in commercial sunscreens for its strong photostability and photoprotection property from harmful UV rays. Such excellent property lies in the ultrafast decay process of the FA system when exposure to the UV light, but the underlying detailed relaxation pathway is still less clear-cut. In the current work, high-level ab initio electronic structure calculations and on-the-fly surface hopping dynamics simulations were employed to explore the photoinduced decay mechanism of the FA system both on the S1 and S3 states in the gas phase. The results provide a reasonable explanation for the wavelength dependent decay patterns of FA system. The S1 state decay pathway is driven by a re-emission process to dissipate excess energy. While for the S3 state deactivation process, the pathway is dominated by a non-adiabatic process driven by the internal conversion process through the conical intersection regions. A S3-S1-S0 two step decay pattern is proposed, and the pathways are mainly driven by a puckering distortion motion of the aromatic ring and a twisting motion around the bridging double bond. The calculation results contribute to a better understanding of detailed dynamics behavior of the FA deactivation process, and provide theoretical guidance for further design of efficient and environmentally friendly sunscreens.
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Affiliation(s)
- Cong-Neng Cao
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, PR China; Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hangzhou 310014, PR China
| | - Cheng-Fu Liu
- School of Pharmaceutical Sciences, Gannan Medical University, Ganzhou 341000, PR China
| | - Li Zhao
- School of Science, China University of Petroleum (East China), Qingdao 266580, Shandong, PR China
| | - Guo-Wu Rao
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, PR China; Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hangzhou 310014, PR China.
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12
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Berenbeim JA, Wong NGK, Cockett MCR, Berden G, Oomens J, Rijs AM, Dessent CEH. Unravelling the Keto-Enol Tautomer Dependent Photochemistry and Degradation Pathways of the Protonated UVA Filter Avobenzone. J Phys Chem A 2020; 124:2919-2930. [PMID: 32208697 PMCID: PMC7168606 DOI: 10.1021/acs.jpca.0c01295] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
Avobenzone (AB) is
a widely used UVA filter known to undergo irreversible
photodegradation. Here, we investigate the detailed pathways by which
AB photodegrades by applying UV laser-interfaced mass spectrometry
to protonated AB ions. Gas-phase infrared multiple-photon dissociation
(IRMPD) spectra obtained with the free electron laser for infrared
experiments, FELIX, (600–1800 cm–1) are also
presented to confirm the geometric structures. The UV gas-phase absorption
spectrum (2.5–5 eV) of protonated AB contains bands that correspond
to selective excitation of either the enol or diketo forms, allowing
us to probe the resulting, tautomer-dependent photochemistry. Numerous
photofragments (i.e., photodegradants) are directly identified for
the first time, with m/z 135 and
161 dominating, and m/z 146 and
177 also appearing prominently. Analysis of the production spectra
of these photofragments reveals that that strong enol to keto photoisomerism
is occurring, and that protonation significantly disrupts the stability
of the enol (UVA active) tautomer. Close comparison of fragment ion
yields with the TD-DFT-calculated absorption spectra give detailed
information on the location and identity of the dissociative excited
state surfaces, and thus provide new insight into the photodegradation
pathways of avobenzone, and photoisomerization of the wider class
of β-diketone containing molecules.
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Affiliation(s)
- Jacob A Berenbeim
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Natalie G K Wong
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Martin C R Cockett
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Giel Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen, 6500 HC, The Netherlands
| | - Jos Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen, 6500 HC, The Netherlands
| | - Anouk M Rijs
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen, 6500 HC, The Netherlands
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13
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Chan CTL, Ma C, Chan RCT, Ou HM, Xie HX, Wong AKW, Wang ML, Kwok WM. A long lasting sunscreen controversy of 4-aminobenzoic acid and 4-dimethylaminobenzaldehyde derivatives resolved by ultrafast spectroscopy combined with density functional theoretical study. Phys Chem Chem Phys 2020; 22:8006-8020. [PMID: 32239002 DOI: 10.1039/c9cp07014a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
4-Aminobenzoic acid (PABA) is one of the earliest patented and most commonly used sunscreen components. There is however a long-lasting controversy on its photo-protective efficacy owing to the lack of information on its protolytic equilibrium and photo-dynamics after absorption of ultraviolet radiation in physiologically relevant aqueous solution. The excitation dynamics in water also remains largely unknown for analogs of PABA such as 4-dimethylaminoacetophenone (DMAAP) and 4-dimethylaminobenzaldehyde (DMABA) which are recognized as prototypes for photo-induced twisted intramolecular charge transfer (TICT). Herein we report a combined application of femtosecond broadband time-resolved fluorescence and transient absorption coupled with density functional theoretical study for PABA, DMAAP, and DMABA under several solvent conditions with representative properties in terms of the pH, polarity and hydrogen bonding capacity. The results we gained demonstrate that, in a neutral aqueous solution, PABA taking the deprotonated anion form in the ground state undergoes rapid protonation after excitation, producing excited state species in the neutral form that may shift effectively by intersystem crossing (ISC) to the long-lasting triplet state capable of damaging nucleic acids. This provides evidence at the molecular level for the detrimental effect of PABA if used as a sunscreen ingredient. In contrast, our investigation on DMAAP and DMABA unveils an unusual solvent controlled deactivation dynamics rendered by the participation of the carbonyl oxygen associated nOπ* state featuring energy and structure strongly responsive to solvent properties. In particular, these molecules in water exhibit solute-solvent hydrogen bonding at the sites of the carbonyl oxygen and the amino nitrogen which is, respectively, weakened and strengthened after the excitation, leading to state reversal and formation of a nOπ* state with a peculiar non-planar structure. This quenches strongly the excitation, eliminates the TICT, suppresses the ISC and opens up the otherwise inaccessible internal conversion (IC) to account for ∼80% of the entire deactivation. The IC, observed to proceed at a rate of ∼2.5 ps, allows the effective recovery of the ground state, providing substantial protection against ultraviolet irradiation. Moreover, the revelation of highly solvent sensitive fluorescence emission from DMABA and DMAAP implies the potential application of these molecules as the functional element in the design of sensory materials for probing the polarity and hydrogen bonding character of the surrounding environment.
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Affiliation(s)
- Chris Tsz-Leung Chan
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Chensheng Ma
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Ruth Chau-Ting Chan
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Hui-Min Ou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Han-Xin Xie
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Allen Ka-Wa Wong
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China.
| | - Ming-Liang Wang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
| | - Wai-Ming Kwok
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P. R. China.
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14
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Bacardit A, Cartoixà X. Revisiting the Role of Irradiance in the Determination of Sunscreens' Sun Protection Factor. J Phys Chem Lett 2020; 11:1209-1214. [PMID: 32075378 DOI: 10.1021/acs.jpclett.9b03437] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The efficacy of a sunscreen tends to be associated with its sun protection factor (SPF) value, a figure determined in a test that relies on the independence of the SPF value to both UV radiation dose and irradiance. We probe these assumptions when photoinduced product degradation is present, and we estimate that the theoretical limit for their validity is when the sunfilter active molecule relaxation time is faster than ∼10 ns. While such threshold relaxation time should be compatible with the expected ultrafast relaxation mechanisms of sunfilter molecules (picoseconds), recent research on sunfilter photodynamics has identified the existence of much longer-lived molecular states. Such long lifetimes could compromise sunscreen performance and make the SPF value very different in natural sun irradiance conditions than in the solar simulated conditions typically used in SPF determination tests.
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Affiliation(s)
| | - Xavier Cartoixà
- Departament d'Enginyeria Electrònica , Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès , Spain
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15
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Dao DQ, Phan TTT, Nguyen TLA, Trinh PTH, Tran TTV, Lee JS, Shin HJ, Choi BK. Insight into Antioxidant and Photoprotective Properties of Natural Compounds from Marine Fungus. J Chem Inf Model 2020; 60:1329-1351. [DOI: 10.1021/acs.jcim.9b00964] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Duy Quang Dao
- Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang 550000, Vietnam
| | - Thi Thu Trang Phan
- Faculty of Pharmacy, Duy Tan University, 03 Quang Trung, Da Nang 550000, Vietnam
| | - Thi Le Anh Nguyen
- Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang 550000, Vietnam
| | - Phan Thi Hoai Trinh
- Nha Trang Institute of Technology Research and Application, Vietnam Academy of Science and Technology (VAST), 02 Hung Vuong, Nha Trang 650000, Vietnam
| | - Thi Thanh Van Tran
- Nha Trang Institute of Technology Research and Application, Vietnam Academy of Science and Technology (VAST), 02 Hung Vuong, Nha Trang 650000, Vietnam
| | - Jong Seok Lee
- Korea Institute of Ocean Science and Technology, 385, Haeyang-ro, Yeongdo-gu, Busan Metropolitan City 49111, Korea
| | - Hee Jae Shin
- Korea Institute of Ocean Science and Technology, 385, Haeyang-ro, Yeongdo-gu, Busan Metropolitan City 49111, Korea
| | - Byeoung-Kyu Choi
- Korea Institute of Ocean Science and Technology, 385, Haeyang-ro, Yeongdo-gu, Busan Metropolitan City 49111, Korea
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16
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Hanson KM, Cutuli M, Rivas T, Antuna M, Saoub J, Tierce NT, Bardeen CJ. Effects of solvent and micellar encapsulation on the photostability of avobenzone. Photochem Photobiol Sci 2020; 19:390-398. [DOI: 10.1039/c9pp00483a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Avobenzone, the only UVA-absorbing molecule approved for use in sunscreens by the FDA, degrades to its diketone structure under UV light. We found that this photoisomerization is effectively prevented when avobenzone is sequestered in micelles.
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Affiliation(s)
- Kerry M. Hanson
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
| | - Miles Cutuli
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
| | - Tiffany Rivas
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
| | - Miranda Antuna
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
| | - Jessica Saoub
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
| | - Nathan T. Tierce
- Department of Chemistry
- University of California
- Riverside
- Riverside
- USA
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17
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Wang J, Lei Y, Guo Y, Wang J, Ma J. Investigation of different photochemical reactions of avobenzone derivatives by ultrafast transient absorption spectroscopy. Photochem Photobiol Sci 2019; 18:3000-3007. [PMID: 31763661 DOI: 10.1039/c9pp00333a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Avobenzone (AB) is one of the most widely used UVA sunscreens, and it is viewed as a model compound for studying the photoisomerization process. In recent years, Miranda and co-workers studied photophysical and photochemical reactions of several AB derivatives. However, there is still a gap in the data of these compounds in the ultrafast time region. To get a better understanding of the photophysical and photochemical reaction mechanisms, selected AB derivatives of AB-Me, AB-Pr, AB-Br and AB-Cl were studied using ultrafast transient absorption spectroscopy and density functional theory calculations in the present study. It is unravelled that alkylated substituted AB compounds of AB-Me and AB-Pr exhibit an efficient intersystem crossing with the generation of the corresponding triplet state species, which further leads to the Norrish type II reaction for AB-Pr. On the other hand, AB-Br and AB-Cl prefer photochemical reactions via the singlet state surface. Based on the DFT calculations, the spin-orbit coupling constant between the singlet and triplet states, the energy difference between the singlet and triplet states and the natural transition orbital separations of the studied AB compounds were found to be the leading reasons accounting for their corresponding photochemical activities via singlet and triplet states.
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Affiliation(s)
- Jialin Wang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
| | - Yibo Lei
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
| | - Yan Guo
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
| | - Junxiao Wang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
| | - Jiani Ma
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
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18
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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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19
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Ma C, Chan CTL, Chan RCT, Wong AKW, Chung BPY, Kwok WM. Photoprotection or photodamage: a direct observation of nonradiative dynamics from 2-ethylhexyl 4-dimethylaminobenzoate sunscreen agent. Phys Chem Chem Phys 2018; 20:24796-24806. [PMID: 30229763 DOI: 10.1039/c8cp04447c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Apart from being an analogue of the prototype for photoinduced intramolecular charge transfer (ICT), 2-ethylhexyl 4-dimethylaminobenzoate (EHDMABA) is also one of the earliest patented and most commonly used sunscreen components. There is, however, little documented information about the photophysics and factors affecting the photophysics of this molecule. Such information is of importance for both the understanding of the ICT reaction and assessing the underlying process of photoprotection, especially in view of the "sunscreen controversy" that has arisen from the contrasting in vivo vs. in vitro photobiological results on this and related UV filters. We report herein a femtosecond broadband time-resolved fluorescence (fs-TRF), complemented by transient absorption (fs-TA) to allow a full probe of the excited state cascades for EHDMABA and two of its derivatives in solvents of varied properties. The results provide direct evidence for a nearly solvent independent inner sphere ICT reaction occurring on the sub-picosecond time scale, and an ensuing solvent dictated deactivation of the ICT state. The ICT state in the aprotic solvent acetonitrile decayed solely through the intrinsic intersystem crossing (ISC) to produce a potentially harmful triplet excited state. In the protic solvent, the solvation and formation of ICT-induced solute-solvent hydrogen (H)-bonding opened the originally inaccessible internal conversion (IC) channel of the ICT state, leading to the rapid reformation of the ground state molecule with a unitary efficiency in the aqueous solution. This H-bonding-mediated IC restrained or eliminated the intrinsic ISC, providing a mechanism at the molecular level for the benign dissipation of the electronic excitation. The precise rate of IC was observed to vary with the alkoxy substituent and its efficiency was affected by the H-bonding capacity of the solvent. The findings of this work demonstrate the pivotal role of the microenvironment and the direct participation of solvent molecules through H-bonding in drastically altering the nonradiative dynamics and promoting or inhibiting photostability and photoprotection. This may assist in developing next-generation UV filters and help in improving formulation design for the optimal efficacy of sunscreen products. The pronounced H-bonding-induced fluorescence quenching and variation in the fluorescence wavelength imply that these molecules may also serve as a sensitive fluorescence probe for the H-bonding properties of the microenvironment.
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Affiliation(s)
- Chensheng Ma
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, P. R. China.
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20
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Inclusion complexes and photostability of UV filters and curcumin with beta-cyclodextrin polymers: effect on cross-linkers. J INCL PHENOM MACRO 2018. [DOI: 10.1007/s10847-018-0796-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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21
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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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22
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Abstract
Despite the pivotal role of ultraviolet (UV) radiation in sustaining life on Earth, overexposure to this type of radiation can have catastrophic effects, such as skin cancer. Sunscreens, the most common form of artificial protection against such harmful effects, absorb UV radiation before it reaches vulnerable skin cells. Absorption of UV radiation prompts ultrafast molecular events in sunscreen molecules which, ideally, would allow for fast and safe dissipation of the excess energy. However, our knowledge of these mechanisms remains limited. In this article, we will review recent advances in the field of ultrafast photodynamics (light induced molecular processes occurring within femtoseconds, fs, 10-15 s to picoseconds, ps, 10-12 s) of sunscreens. We follow a bottom-up approach to common sunscreen active ingredients, analysing any emerging trends from the current literature on the subject. Moreover, we will identify the main questions that remain unanswered, pinpoint some of the main challenges and finally comment on the outlook of this exciting field of research.
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23
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Ma C, Ou YQ, Chan CTL, Wong AKW, Chan RCT, Chung BPY, Jiang C, Wang ML, Kwok WM. Nonradiative dynamics determined by charge transfer induced hydrogen bonding: a combined femtosecond time-resolved fluorescence and density functional theoretical study of methyl dimethylaminobenzoate in water. Phys Chem Chem Phys 2018; 20:1240-1251. [DOI: 10.1039/c7cp05140a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrogen bonding with water alters nonradiative pathway of a twisted charge transfer state in methyl dimethylaminobenzoate.
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Affiliation(s)
- Chensheng Ma
- College of Chemistry and Environmental Engineering
- Shenzhen University
- Shenzhen
- P. R. China
| | - Yue-Qun Ou
- College of Chemistry and Environmental Engineering
- Shenzhen University
- Shenzhen
- P. R. China
| | - Chris Tsz-Leung Chan
- College of Chemistry and Environmental Engineering
- Shenzhen University
- Shenzhen
- P. R. China
| | - Allen Ka-Wa Wong
- Department of Applied Biology and Chemical Technology
- The Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Ruth Chau-Ting Chan
- Department of Applied Biology and Chemical Technology
- The Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Bowie Po-Yee Chung
- Department of Applied Biology and Chemical Technology
- The Hong Kong Polytechnic University
- Kowloon
- P. R. China
| | - Chao Jiang
- College of Chemistry and Environmental Engineering
- Shenzhen University
- Shenzhen
- P. R. China
| | - Ming-Liang Wang
- College of Chemistry and Environmental Engineering
- Shenzhen University
- Shenzhen
- P. R. China
| | - Wai-Ming Kwok
- Department of Applied Biology and Chemical Technology
- The Hong Kong Polytechnic University
- Kowloon
- P. R. China
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24
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Gezegen H, Hepokur C, Tutar U, Ceylan M. Synthesis and Biological Evaluation of Novel 1-(4-(Hydroxy(1-oxo-1,3-dihydro-2H
-inden-2-ylidene)methyl)phenyl)-3-phenylurea Derivatives. Chem Biodivers 2017; 14. [DOI: 10.1002/cbdv.201700223] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/27/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Hayreddin Gezegen
- Department of Nutrition and Dietetics; Faculty of Health Sciences; Cumhuriyet University; 58140 Sivas Turkey
| | - Ceylan Hepokur
- Department of Biochemistry; Faculty of Pharmacy; Cumhuriyet University; 58140 Sivas Turkey
| | - Uğur Tutar
- Department of Nutrition and Dietetics; Faculty of Health Sciences; Cumhuriyet University; 58140 Sivas Turkey
| | - Mustafa Ceylan
- Department of Chemistry; Faculty of Arts and Sciences; Gaziosmanpasa University; 60250 Tokat Turkey
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25
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Matsumoto S, Kumasaka R, Yagi M, Kikuchi A. Triplet–triplet energy transfer between UV absorbers in solutions at room temperature. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.06.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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26
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Wang C, Bavcon Kralj M, Košmrlj B, Yao J, Košenina S, Polyakova OV, Artaev VB, Lebedev AT, Trebše P. Stability and removal of selected avobenzone's chlorination products. CHEMOSPHERE 2017; 182:238-244. [PMID: 28500968 DOI: 10.1016/j.chemosphere.2017.04.125] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 04/13/2017] [Accepted: 04/18/2017] [Indexed: 06/07/2023]
Abstract
Stability studies of two avobenzone transformation products: chloro-avobenzone [2-chloro-1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)-1,3-propanedione] and dichloro-avobenzone [2,2-dichloro-1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)-1,3-propanedione] have been performed at different pHs values as well as under UV A light and compared with the stability of avobenzone, one of the mostly used UV A filter present in sunscreens. We have additionally investigated the possibility of application of TiO2 photocatalysis as a method for the removal of them. Results have shown the differences in pH stability of all three studied compounds with much slower degradation rate under neutral conditions in comparison to the acidic ones for all three studied compounds. In the case of photolytic experiment, performed under UV A light, dichloro-avobenzone exhibited the lowest UVA stability (half-life 22.4 ± 0.7 min), while avobenzone and chloro-avobenzone are much more stable and have shown quite similar degradation pattern (half-lives 126 ± 16 min and 128 ± 25 min). Under the photocatalytic conditions the less stable was dichloro-avobenzone (half-life 14.1 ± 0.6 min), while chloro-avobenzone and avobenzone were much more stable (half-lives 41 ± 3 min and 79 ± 13 min). Dichloroavobenzone is significantly more reactive than avobenzone and its monochloro-derivative. On the basis of the formation of various stable degradation products, including substituted acetophenones, benzoic acids and phenols, identified by GC-MS, the degradation pathway has been proposed.
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Affiliation(s)
- Cheng Wang
- Faculty of Energy, Environmental Science and Engineering, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing, China
| | - Mojca Bavcon Kralj
- Faculty of Health Sciences, University of Ljubljana, Zdravstvena pot 5, 1000 Ljubljana, Slovenia
| | - Berta Košmrlj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Jun Yao
- Faculty of Energy, Environmental Science and Engineering, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing, China
| | - Suzana Košenina
- Faculty of Health Sciences, University of Ljubljana, Zdravstvena pot 5, 1000 Ljubljana, Slovenia
| | - Olga V Polyakova
- Organic Chemistry Department, M.V.Lomonosov Moscow State University, Moscow 119991, Russia
| | | | - Albert T Lebedev
- Organic Chemistry Department, M.V.Lomonosov Moscow State University, Moscow 119991, Russia.
| | - Polonca Trebše
- Faculty of Health Sciences, University of Ljubljana, Zdravstvena pot 5, 1000 Ljubljana, Slovenia.
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27
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Shamoto Y, Yagi M, Oguchi-Fujiyama N, Miyazawa K, Kikuchi A. Photophysical properties of hexyl diethylaminohydroxybenzoylbenzoate (Uvinul A Plus), a UV-A absorber. Photochem Photobiol Sci 2017; 16:1449-1457. [DOI: 10.1039/c7pp00164a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
DHHB (photostable UV-A absorber) may act as a triplet energy donor for OMC (the most widely used UV-B absorber) because the T1energy of DHHB is higher than that of OMC.
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Affiliation(s)
- Yuta Shamoto
- Department of Chemistry
- Graduate School of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
| | - Mikio Yagi
- Department of Chemistry
- Graduate School of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
| | | | | | - Azusa Kikuchi
- Department of Chemistry
- Graduate School of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
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28
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Binks BP, Fletcher PD, Johnson AJ, Marinopoulos I, Crowther J, Thompson MA. How the sun protection factor (SPF) of sunscreen films change during solar irradiation. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2016.10.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Baker LA, Greenough SE, Stavros VG. A Perspective on the Ultrafast Photochemistry of Solution-Phase Sunscreen Molecules. J Phys Chem Lett 2016; 7:4655-4665. [PMID: 27791379 DOI: 10.1021/acs.jpclett.6b02104] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sunscreens are one of the most common ways of providing on-demand additional photoprotection to the skin. Ultrafast transient absorption spectroscopy has recently proven to be an invaluable tool in understanding how the components of commercial sunscreen products display efficient photoprotection. Important examples of how this technique has unravelled the photodynamics of common components are given in this Perspective, and some of the remaining unanswered questions are discussed.
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Affiliation(s)
- Lewis A Baker
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Simon E Greenough
- Department of Chemistry, University of Sheffield , Sheffield S3 7HF, United Kingdom
| | - Vasilios G Stavros
- Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
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30
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Suwa Y, Yamaji M. Steady state and laser photolysis studies of keto-enol tautomerizations in 2-alkyl-1,3-diketones having five-membered rings in acetonitrile: Temporal UV-A sunscreen. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2015.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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31
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Kojić M, Petković M, Etinski M. A new insight into the photochemistry of avobenzone in gas phase and acetonitrile from ab initio calculations. Phys Chem Chem Phys 2016; 18:22168-78. [DOI: 10.1039/c6cp03533g] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coupled cluster based calculations on the ground and excited states of avobenzone provide mechanistic understanding of formation of transient tautomers upon photoexcitation of the chelated enol form.
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Affiliation(s)
- Marko Kojić
- Faculty of Physical Chemistry
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Milena Petković
- Faculty of Physical Chemistry
- University of Belgrade
- 11000 Belgrade
- Serbia
| | - Mihajlo Etinski
- Faculty of Physical Chemistry
- University of Belgrade
- 11000 Belgrade
- Serbia
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32
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Photostability of water-soluble inclusion complexes of UV-filters and curcumin with gamma-cyclodextrin polymer. J INCL PHENOM MACRO 2015. [DOI: 10.1007/s10847-015-0589-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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33
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Trossini GHG, Maltarollo VG, Garcia RD, Pinto CASO, Velasco MVR, Honorio KM, Baby AR. Theoretical study of tautomers and photoisomers of avobenzone by DFT methods. J Mol Model 2015; 21:319. [DOI: 10.1007/s00894-015-2863-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 11/15/2015] [Indexed: 10/22/2022]
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34
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Mandal S, Bera R, Das S, Nayak SK, Pramanik A, Patra A. Photon Harvesting in Sunscreen-Based Functional Nanoparticles. Chemphyschem 2015; 16:3618-24. [PMID: 26419334 DOI: 10.1002/cphc.201500780] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Indexed: 11/12/2022]
Abstract
The ultraviolet light component in the solar spectrum is known to cause several harmful effects, such as allergy, skin ageing, and skin cancer. Thus, current research attention has been paid to the design and fundamental understanding of sunscreen-based materials. One of the most abundantly used sunscreen molecules is Avobenzone (AB), which exhibits two tautomers. Here, we highlight the preparation of spherically shaped nanoparticles from the sunscreen molecule AB as well as from sunscreen-molecule-encapsulated polymer nanoparticles in aqueous media and study their fundamental photophysical properties by steady-state and time-resolved spectroscopy. Steady-state studies confirm that the AB molecule is in the keto and enol forms in tetrahydrofuran, whereas the enol form is stable in the case of both AB nanoparticles and AB-encapsulated poly(methyl methacrylate) (PMMA) nanoparticles. Thus, the keto-enol transformation of AB molecules is restricted to a nanoenvironment. An enhancement of photostability in both the nanoparticle and PMMA-encapsulated forms under UV light irradiation is observed. The efficient excited energy transfer (60 %) from AB to porphyrin molecules opens up further prospects in potential applications as light-harvesting systems.
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Affiliation(s)
- Sadananda Mandal
- Department of Materials Science, Indian Association for the Cultivation of Science, Kolkata, 700 032, India.,Department of Chemistry, Vivekananda Mahavidyalaya, Burdwan, Sripally, Burdwan-, 713103, West Bengal, India
| | - Rajesh Bera
- Department of Materials Science, Indian Association for the Cultivation of Science, Kolkata, 700 032, India
| | - Somnath Das
- Unilever R & D Bangalore, 64, Main Road, Whitefield, Bangalore, 560066, India
| | - Sandip K Nayak
- Bio-organic Division, Bhabha Atomic Research Centre, Mumbai-, 400 085, India
| | - Amitava Pramanik
- Unilever R & D Bangalore, 64, Main Road, Whitefield, Bangalore, 560066, India.
| | - Amitava Patra
- Department of Materials Science, Indian Association for the Cultivation of Science, Kolkata, 700 032, India.
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35
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Chisholm MH, Gustafson TL, Kender WT, Spilker TF, Young PJ. Electronic and spectroscopic properties of avobenzone derivatives attached to ditungsten quadruple bonds. Inorg Chem 2015; 54:9438-46. [PMID: 26389702 DOI: 10.1021/acs.inorgchem.5b01221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
From the reactions between W2(T(i)PB)4, where T(i)PB is 2,4,6-triisopropylbenzoate, and 2 equiv of acid, 4-formylbenzoic acid, HBzald, 4-(3-oxo-3-phenylpropanoyl)benzoic acid, HAvo, or 4-(2,2-difluoro-6-phenyl-2H-1λ(3),3,2λ(4)-dioxaborinin-4-yl)benzoic acid, HAvoBF2, three new compounds W2(T(i)PB)2(Bzald)2, I, W2(T(i)PB)2(Avo)2, II, and W2(T(i)PB)2(AvoBF2)2, III, have been prepared. As solid compounds I and II are blue while compound III is green. Characterization of these compounds has been carried out by means of (1)H NMR, MALDI-TOF MS, steady-state absorption and emission spectroscopies, and femtosecond and nanosecond transient absorption and time-resolved infrared spectroscopies. Compounds I and II have strong metal to ligand charge transfer, MLCT, transitions in the visible region of their spectra while compound III exhibits MLCT absorption in the near-infrared (λmax = 1017 nm). All three have S1 states that have corresponding lifetimes of ∼3-30 ps and are (1)MLCT in character. The triplet states are (3)MLCT with lifetimes in the range 3-10 ns. Density functional theory and time-dependent density functional theory were employed to perform electronic structure calculations in order to aid in the interpretation of these data. The spectroscopic properties of I and II are similar while the planarity of the ligand in III greatly lowers the energy of the MLCT state. The W2 unit enables direct observation of intersystem crossing from the (1)MLCT state to (3)MLCT state via the use of ultrafast spectroscopy.
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Affiliation(s)
- Malcolm H Chisholm
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Terry L Gustafson
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - William T Kender
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Thomas F Spilker
- Department of Macromolecular Science and Engineering, Case Western Reserve University , 2080 Adelbert Road, Cleveland, Ohio 44106, United States
| | - Philip J Young
- Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States
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Dunkelberger AD, Kieda RD, Marsh BM, Crim FF. Picosecond Dynamics of Avobenzone in Solution. J Phys Chem A 2015; 119:6155-61. [DOI: 10.1021/acs.jpca.5b01641] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Adam D. Dunkelberger
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Ryan D. Kieda
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Brett M. Marsh
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - F. Fleming Crim
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
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37
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Chisholm MH, Durr CB, Gustafson TL, Kender WT, Spilker TF, Young PJ. Electronic and Spectroscopic Properties of Avobenzone Derivatives Attached to Mo2 Quadruple Bonds: Suppression of the Photochemical Enol-to-Keto Transformation. J Am Chem Soc 2015; 137:5155-62. [PMID: 25856290 DOI: 10.1021/jacs.5b01495] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Malcolm H. Chisholm
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Christopher B. Durr
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Terry L. Gustafson
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - William T. Kender
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Thomas F. Spilker
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Philip J. Young
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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38
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Ekebergh A, Sandin P, Mårtensson J. On the photostability of scytonemin, analogues thereof and their monomeric counterparts. Photochem Photobiol Sci 2015; 14:2179-86. [DOI: 10.1039/c5pp00215j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Observation of unexpectedly rapid photodegradation of the cyanobacterial UV-screener scytoneminin vitro.
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Affiliation(s)
- Andreas Ekebergh
- Department of Chemistry and Chemical Engineering/Organic and Physical Chemistry
- Chalmers University of Technology
- SE-412 96 Gothenburg
- Sweden
| | - Peter Sandin
- Department of Chemistry and Chemical Engineering/Organic and Physical Chemistry
- Chalmers University of Technology
- SE-412 96 Gothenburg
- Sweden
| | - Jerker Mårtensson
- Department of Chemistry and Chemical Engineering/Organic and Physical Chemistry
- Chalmers University of Technology
- SE-412 96 Gothenburg
- Sweden
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39
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Yamaji M, Suwa Y, Shimokawa R, Paris C, Miranda MÁ. Photochemical reactions of halogenated aromatic 1,3-diketones in solution studied by steady state, one- and two-color laser flash photolyses. Photochem Photobiol Sci 2015; 14:1673-84. [DOI: 10.1039/c5pp00211g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoreactions of 1,3-diketones having halogen atoms at the C2 position are investigated by steady state, one- and two-color laser photolyses and DFT calculation.
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Affiliation(s)
- Minoru Yamaji
- Division of Molecular Science
- Graduate School of Science and Engineering
- Gunma University
- Kiryu
- Japan
| | - Yurie Suwa
- Education Program of Materials and Bioscience
- Graduate School of Science and Engineering
- Gunma University
- Kiryu
- Japan
| | - Rieko Shimokawa
- Education Program of Materials and Bioscience
- Graduate School of Science and Engineering
- Gunma University
- Kiryu
- Japan
| | - Cecilia Paris
- Instituto de Tecnologia Química UPV-CSIC
- Universidad Politécnica de Valencia
- Valencia
- Spain
| | - Miguel Ángel Miranda
- Instituto de Tecnologia Química UPV-CSIC
- Universidad Politécnica de Valencia
- Valencia
- Spain
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40
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Kumasaka R, Kikuchi A, Yagi M. Photoexcited states of UV absorbers, benzophenone derivatives. Photochem Photobiol 2014; 90:727-33. [PMID: 24571426 DOI: 10.1111/php.12257] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/10/2014] [Indexed: 12/31/2022]
Abstract
The UV absorption, phosphorescence and phosphorescence-excitation spectra of benzophenone (BP) derivatives used as organic UV absorbers have been observed in rigid solutions at 77 K. The triplet-triplet absorption spectra have been observed in acetonitrile at room temperature. The BP derivatives studied are 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone (BP-6), 5-chloro-2-hydroxybenzophenone (BP-7) and 2-hydroxy-4-n-octyloxybenzophenone (BP-12). The energy levels and lifetimes of the lowest excited triplet (T1 ) states of these BP derivatives were determined from the first peak of phosphorescence. The time-resolved near-IR emission spectrum of singlet oxygen generated by photosensitization with BP-7 was observed in acetonitrile at room temperature. BP-2, BP-3, BP-6 and BP-12 show photoinduced phosphorescence enhancement in ethanol at 77 K. The possible mechanism of the observed phosphorescence enhancement is discussed. The T1 states of 2-hydroxy-5-methylbenzophenone, 4-methoxybenzophenone and 2,4'-dimethoxybenzophenone have been studied for comparison.
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Affiliation(s)
- Ryo Kumasaka
- Department of Chemistry, Graduate School of Engineering, Yokohama National University, Tokiwadai, Hodogaya-ku, Yokohama, Japan
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41
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Kikuchi A, Oguchi-Fujiyama N, Miyazawa K, Yagi M. Triplet-Triplet Energy Transfer from a UV-A Absorber Butylmethoxydibenzoylmethane to UV-B Absorbers. Photochem Photobiol 2014; 90:511-6. [DOI: 10.1111/php.12222] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/04/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Azusa Kikuchi
- Department of Chemistry; Graduate School of Engineering; Yokohama National University; Hodogaya-ku Yokohama Japan
| | | | | | - Mikio Yagi
- Department of Chemistry; Graduate School of Engineering; Yokohama National University; Hodogaya-ku Yokohama Japan
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