1
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Liu XY, Wang SR, Fang WH, Cui G. Nuclear Quantum Effects on Nonadiabatic Dynamics of a Green Fluorescent Protein Chromophore Analogue: Ring-Polymer Surface-Hopping Simulation. J Chem Theory Comput 2024; 20:3426-3439. [PMID: 38656202 DOI: 10.1021/acs.jctc.4c00068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Herein, we have used the "on-the-fly" ring-polymer surface-hopping simulation method with the centroid approximation (RPSH-CA), in combination with the multireference OM2/MRCI electronic structure calculations to study the photoinduced dynamics of a green fluorescent protein (GFP) chromophore analogue in the gas phase, i.e., o-HBI, at 50, 100, and 300 K with 1, 5, 10, and 15 beads (3600 1 ps trajectories). The electronic structure calculations identified five new minimum-energy conical intersection (MECI) structures, which, together with the previous one, play crucial roles in the excited-state decay dynamics of o-HBI. It is also found that the excited-state intramolecular proton transfer (ESIPT) occurs in an ultrafast manner and is completed within 20 fs in all the simulation conditions because there is no barrier associated with this ESIPT process in the S1 state. However, the other excited-state dynamical results are strongly related to the number of beads. At 50 and 100 K, the nuclear quantum effects (NQEs) are very important; therefore, the excited-state dynamical results change significantly with the bead number. For example, the S1 decay time deduced from time-dependent state populations becomes longer as the bead number increases. Nevertheless, an essentially convergent trend is observed when the bead number is close to 10. In contrast, at 300 K, the NQEs become weaker and the above dynamical results converge very quickly even with 1 bead. Most importantly, the NQEs seriously affect the excited-state decay mechanism of o-HBI. At 50 and 100 K, most trajectories decay to the S0 state via perpendicular keto MECIs, whereas, at 300 K, only twisted keto MECIs are responsible for the excited-state decay. The present work not only comprehensively explores the temperature-dependent photoinduced dynamics of o-HBI, but also demonstrates the importance and necessity of NQEs in nonadiabatic dynamics simulations, especially at relatively low temperatures.
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Affiliation(s)
- Xiang-Yang Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China
| | - Sheng-Rui Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, 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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2
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Tang X, Zhang Y, Sun C. Effect of external electric fields on the ESDPT process and photophysical properties of 1,8-dihydroxy-2-naphthaldehyde. Phys Chem Chem Phys 2024; 26:10439-10448. [PMID: 38502564 DOI: 10.1039/d3cp06175b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
In this work, by capitalizing on the density functional theory (DFT) and the time-dependent density functional theory (TD-DFT) methods, it has been systematically studied that the excited state double intramolecular proton transfer (ESDPT) process and the photophysical properties of 1,8-dihydroxy-2-naphthaldehyde (DHNA) are affected by the distinct external electric fields (EEFs). The obtained intramolecular hydrogen bond (IHB) parameters containing bond lengths and angles, as well as infrared (IR) vibrational spectra demonstrate that IHB strength changes in the distinct EEFs. Moreover, not only do the potential energy surfaces (PESs) indicate that the ESDPT process of DHNA is stepwise, but also increasing the positive EEF results in a decrease in the energy barrier accordingly, while vice versa. The absorption and fluorescence spectra also undergo a corresponding red or blue shift in the EEF; for instance, when the EEF changes from +10 × 10-4 a.u. to +20 × 10-4 a.u., the fluorescence peak undergoes a blue shift from 602 nm to 513 nm in the keto2 form. In a nutshell, the ESDPT process of DHNA can be influenced by the EEF, which will serve as a reference in regulating and controlling proton transfer that causes luminescence.
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Affiliation(s)
- Xingzhu Tang
- College of Science, Northeast Forestry University, Harbin 150040, Heilongjiang, China.
| | - Yajie Zhang
- College of Science, Northeast Forestry University, Harbin 150040, Heilongjiang, China.
| | - Chaofan Sun
- College of Science, Northeast Forestry University, Harbin 150040, Heilongjiang, China.
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3
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Lin Z, Liu S, Weng W, Wang C, Guo J. Photostimulated Covalent Linkage Transformation Isomerizing Covalent Organic Frameworks for Improved Photocatalytic Performances. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2307138. [PMID: 37875766 DOI: 10.1002/smll.202307138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/05/2023] [Indexed: 10/26/2023]
Abstract
Covalent organic frameworks (COFs) offer a desirable platform to explore multichoromophoric arrays for photocatalytic conversion. Symmetric arrangement of choromophoric modules over π-extended frameworks enhances exciton delocalization while impairing excitation density and accordingly photochemical reactivity. Herein, a photoisomerization-driven strategy is proposed to break the excited-state symmetry of ketoenamine-linked COFs with multichoromophoric arrays. Incorporating electron-withdrawing benzothiadiazole facilitates the ultrafast excited-state intramolecular proton transfer (ESIPT) from enamine to keto within 140 fs, resulting in partially enolized COF isomers. The hybrid linkages containing imine and enamine bonds at the node of framework alter the symmetry of electronic structure and enforce the photoinduced charge separation. Increasing the imine-to-enamine ratio further promotes the electron transferred number in a long range, thereby affording the optimum photocatalytic hydrogen evolution rate. This work put forward an ESIPT-induced photoisomerization to build a symmetry-breaking COF with weakened exciton effect and enhanced photochemical reactivity.
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Affiliation(s)
- Zheng Lin
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China
| | - Shujing Liu
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China
| | - Weijun Weng
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China
| | - Changchun Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China
| | - Jia Guo
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438, China
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4
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Wang JK, Wang CH, Wu CC, Chang KH, Wang CH, Liu YH, Chen CT, Chou PT. Hydrogen-Bonded Thiol Undergoes Unconventional Excited-State Intramolecular Proton-Transfer Reactions. J Am Chem Soc 2024; 146:3125-3135. [PMID: 38288596 PMCID: PMC10859960 DOI: 10.1021/jacs.3c10405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/06/2024] [Accepted: 01/08/2024] [Indexed: 02/08/2024]
Abstract
The chapter on the thiol-related hydrogen bond (H-bond) and its excited-state intramolecular proton-transfer (ESIPT) reaction was recently opened where compound 4'-diethylamino-3-mercaptoflavone (3NTF) undergoes ESIPT in both cyclohexane solution and solid, giving a 710 nm tautomer emission with an anomalously large Stokes shift of 12,230 cm-1. Considering the thiol H-bond to be unconventional compared to the conventional Pauling-type -OH or -NH H-bond, it is thus essential and timely to probe its fundamental difference between their ESIPT. However, thiol-associated ESIPT tends to be nonemissive due to the dominant nπ* character of the tautomeric lowest excited state. Herein, based on the 3-mercaptoflavone scaffold and π-elongation concept, a new series of 4'-substituted-7-diethylamino-3-mercaptoflavones, NTFs, was designed and synthesized with varied H-bond strength and 690-720 nm tautomeric emission upon ultraviolet (UV) excitation in cyclohexane. The order of their H-bonding strength was experimentally determined to be N-NTF < O-NTF < H-NTF < F-NTF, while the rate of -SH ESIPT measured by fluorescence upconversion was F-NTF (398 fs)-1 < H-NTF (232 fs)-1 < O-NTF (123 fs)-1 < N-NTF (101 fs)-1 in toluene. Unexpectedly, the strongest H-bonded F-NTF gives the slowest ESIPT, which does not conform to the traditional ESIPT model. The results are rationalized by the trend of carbonyl oxygen basicity rather than -SH acidity. Namely, the thiol acidity relevant to the H-bond strength plays a minor role in the driving force of ESIPT. Instead, the proton-accepting strength governs ESIPT. That is to say, the noncanonical thiol H-bonding system undergoes an unconventional type of ESIPT.
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Affiliation(s)
- Jian-Kai Wang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Chih-Hsing Wang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Chi-Chi Wu
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Kai-Hsin Chang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Chun-Hsiang Wang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Yi-Hung Liu
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
| | - Chao-Tsen Chen
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
- Center
for Emerging Material and Advanced Devices, National Taiwan University, Taipei 10617, Taiwan, Republic of China
| | - Pi-Tai Chou
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan, Republic of
China
- Center
for Emerging Material and Advanced Devices, National Taiwan University, Taipei 10617, Taiwan, Republic of China
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5
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Chen L, He H, Huang X, Xu H, Yu Y. Control of the fluorescence molecule 2-(2'-hydroxyphenyl) benzothiazole derivatives by introducing electron-donating and withdrawing substituents groups. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 296:122666. [PMID: 37043917 DOI: 10.1016/j.saa.2023.122666] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 03/19/2023] [Accepted: 03/23/2023] [Indexed: 06/19/2023]
Abstract
Using density functional theory (DFT) and time-dependent density functional theory (TDDFT), we investigate the fluorescence mechanism of (E)-4-(3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methylstyryl)-1-methylpyridin-1-ium (HBTMY) and the excited-state intramolecular proton transfer process (ESIPT) of hydroxyphenyl. Herein, we introduce two electron-donating (amino and methoxy) and two electron-withdrawing (hydrogen and cyano) groups into HBTMY to study their effects on the fluorescence and the ESIPT process. Structural parameters, infrared vibration frequency, vertical excitation and emission energies as well as frontier molecular orbitals show that the substituents have different impacts on intramolecular hydrogen bonding behavior. The result shows that the fluorescence wavelength of molecules with the amino group could reach the near-infrared area, which favors using this fluorescence in the living cell. As the ability of electron-absorbing groups increases, the forward energy barrier in the potential energy curves decreases sharply making the ESIPT process more familiar to take place. Thus, this work offers a guide for cell imaging and provides strategies to adjust and control fluorescence by introducing substituents.
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Affiliation(s)
- Lu Chen
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China
| | - Haixiang He
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China; Guangxi Key Laboratory of Electrochemical Energy Materials, Nanning 530004, PR China; Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China.
| | - Xindi Huang
- Guangxi Institute of Metrology and Test, Nanning 530004, PR China
| | - Honghong Xu
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China
| | - Yan Yu
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China
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6
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Feng Y, Huang X, Lv M, Yu Y, Jiang G, He H, Liu J. The two-pronged approach of heteroatoms and substituents to achieve a synergistic regulation of the ESIPT process in amino 2-(2'-hydroxyphenyl)benzoxazole derivatives. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 291:122318. [PMID: 36623347 DOI: 10.1016/j.saa.2023.122318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/28/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Amino 2-(2'-hydroxyphenyl)benzazole derivatives are a class of molecules with excellent photophysical properties. Most of them can be applied as a fluorescent probe via the excited-state intramolecular proton transfer (ESIPT) process. In this work, we focus on the effects of heteroatoms (O, S) and substituents (acetylacetone, hydrogen) in the derivatives. Using DFT/TDDFT methods with the B3LYP-D3BJ functionals, the absorption and emission peaks are in good agreement with the experimental data. Results of optimized structures, infrared vibrational spectra, and reduced density gradient present the existence of the ESIPT process in the S1 state in these molecules, it also indirectly shows that the heteroatom S is more than O, and the substituent acetylacetone is more than hydrogen has stronger hydrogen bonds. The proton transfer (PT) potential energy curves (PECs) qualitatively show that it is easier for the heteroatom S to induce ESIPT than that of O. The same for the substituent acetylacetone than that of hydrogen. Under the joint influence of the simultaneous stacking of heteroatom S and acetylacetone substituent, the energy barrier of the PT process can be effectively lowered, realizing a synergistic strategy, which can provide some guidance for the design of fluorescent materials.
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Affiliation(s)
- Yu Feng
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China; State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China
| | - Xindi Huang
- Guangxi Institute of Metrology and Test, Nanning 530004, PR China
| | - Meiheng Lv
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China; College of Science, Shenyang University of Chemical Technology, Shenyang 110142, PR China
| | - Yan Yu
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China
| | - Gaoshang Jiang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Haixiang He
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China; Guangxi Key Laboratory of Electrochemical Energy Materials, Nanning 530004, PR China.
| | - Jianyong Liu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China.
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7
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Demchenko AP. Proton transfer reactions: from photochemistry to biochemistry and bioenergetics. BBA ADVANCES 2023. [DOI: 10.1016/j.bbadva.2023.100085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
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8
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Pinheiro M, Zhang S, Dral PO, Barbatti M. WS22 database, Wigner Sampling and geometry interpolation for configurationally diverse molecular datasets. Sci Data 2023; 10:95. [PMID: 36792601 PMCID: PMC9931705 DOI: 10.1038/s41597-023-01998-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 02/01/2023] [Indexed: 02/17/2023] Open
Abstract
Multidimensional surfaces of quantum chemical properties, such as potential energies and dipole moments, are common targets for machine learning, requiring the development of robust and diverse databases extensively exploring molecular configurational spaces. Here we composed the WS22 database covering several quantum mechanical (QM) properties (including potential energies, forces, dipole moments, polarizabilities, HOMO, and LUMO energies) for ten flexible organic molecules of increasing complexity and with up to 22 atoms. This database consists of 1.18 million equilibrium and non-equilibrium geometries carefully sampled from Wigner distributions centered at different equilibrium conformations (either at the ground or excited electronic states) and further augmented with interpolated structures. The diversity of our datasets is demonstrated by visualizing the geometries distribution with dimensionality reduction as well as via comparison of statistical features of the QM properties with those available in existing datasets. Our sampling targets broader quantum mechanical distribution of the configurational space than provided by commonly used sampling through classical molecular dynamics, upping the challenge for machine learning models.
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Affiliation(s)
- Max Pinheiro
- Aix Marseille University, CNRS, ICR, Marseille, France.
| | - Shuang Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Department of Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
| | - Pavlo O Dral
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Department of Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
| | - Mario Barbatti
- Aix Marseille University, CNRS, ICR, Marseille, France.
- Institut Universitaire de France, 75231, Paris, France.
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9
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Lee J, Shin P, Chou PT, Joo T. Excited State Intramolecular Proton Transfer Dynamics of Derivatives of the Green Fluorescent Protein Chromophore. Int J Mol Sci 2023; 24:ijms24043448. [PMID: 36834871 PMCID: PMC9962057 DOI: 10.3390/ijms24043448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/04/2023] [Accepted: 02/04/2023] [Indexed: 02/11/2023] Open
Abstract
Excited state intramolecular proton transfer (ESIPT) dynamics of the o-hydroxy analogs of the green fluorescent protein (GFP) chromophore have been investigated by time-resolved spectroscopies and theoretical calculations. These molecules comprise an excellent system to investigate the effect of electronic properties on the energetics and dynamics of ESIPT and to realize applications in photonics. Time-resolved fluorescence with high enough resolution was employed to record the dynamics and the nuclear wave packets in the excited product state exclusively in conjunction with quantum chemical methods. The ESIPT are ultrafast occurring in 30 fs for the compounds employed in this work. Although the ESIPT rates are not affected by the electronic properties of the substituents suggesting barrierless reaction, the energetics, their structures, subsequent dynamics following ESIPT, and possibly the product species are distinct. The results attest that fine tuning of the electronic properties of the compounds may modify the molecular dynamics of ESIPT and subsequent structural relaxation to achieve brighter emitters with broad tuning capabilities.
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Affiliation(s)
- Junghwa Lee
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Pyoungsik Shin
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan, China
- Correspondence: (P.-T.C.); (T.J.)
| | - Taiha Joo
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Correspondence: (P.-T.C.); (T.J.)
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10
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Lama B, Sarma M. Unraveling the Mechanistic Pathway for the Dual Fluorescence in Green Fluorescent Protein (GFP) Chromophore Analogue: A Detailed Theoretical Investigation. J Phys Chem B 2022; 126:9930-9944. [PMID: 36354358 DOI: 10.1021/acs.jpcb.2c03842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The photophysical properties of the para-sulfonamide (p-TsABDI) analogue of the green fluorescent protein (GFP) chromophore with both proton donating and accepting sites have been exploited in polar solvents to understand the origin of the unusual dual fluorescence nature of the chromophore. In the polar solvents, the compound undergoes structural rearrangement upon photoexcitation, leading to the ultrafast excited-state intermolecular proton transfer (ESIPT) phenomenon at the S1 surface. In this work, we employed both the static electronic structure calculations and on-the-fly molecular dynamics simulation to unravel the underlying reason for this peculiar behavior of the p-TsABDI analogue in polar solvents. To represent this adequately and provide extensive information on the ESIPT mechanism mediated by the solvent molecules, we considered explicit solvent molecules using the integral equation formalism variant of polarizable continuum (IEFPCM) model. From the static calculation analysis, we can conclude that the dual emissive behavior of the compound is ascribed to the proton transfer (PT) phenomena in the excited-state. However, based on the static calculation exclusively, it is hard to ascertain the mechanistic pathway of the PT phenomena. Hence, to investigate the dynamics and reaction mechanism for the ESIPT process, we performed the on-the-fly dynamics simulation for p-TsABDI in solvent clusters. Dynamics simulation results reveal that, based on the time lag between all the proton transfer processes, the ESIPT mechanism occurs in a stepwise manner from the benzylidene moiety of the chromophore to its imidazolinone moiety. However, the nonexistence of crossings between the S1- and S0-states confirms the PT characteristics of the reactions.
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Affiliation(s)
- Bittu Lama
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam781039, India
| | - Manabendra Sarma
- Department of Chemistry, Indian Institute of Technology, Guwahati, Assam781039, India
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11
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Boulanger SA, Chen C, Myasnyanko IN, Baranov MS, Fang C. Fluorescence Modulation of ortho-Green Fluorescent Protein Chromophores Following Ultrafast Proton Transfer in Solution. J Phys Chem B 2022; 126:5081-5093. [PMID: 35786966 DOI: 10.1021/acs.jpcb.2c03812] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photophysical and photochemical properties of the green fluorescent protein (GFP) chromophore and derivatives underlie their bioimaging applications. To date, ultrafast spectroscopic tools represent the key for unraveling fluorescence mechanisms toward rational design of this powerful biomimetic framework. To correlate the excited-state intramolecular proton transfer (ESIPT) with chromophore emission properties, we implement experimental and computational tool sets to elucidate real-time electronic and structural dynamics of two archetypal ortho-GFP chromophores (o-HBDI and o-LHBDI) possessing an intramolecular hydrogen bond to undergo efficient ESIPT, only differing in a bridge-bond constraint. Using excited-state femtosecond stimulated Raman spectroscopy (FSRS), a low-frequency phenolic (P)-ring-deformation mode (∼562 cm-1) was uncovered to accompany ESIPT. The tautomerized chromophore undergoes either rapid P-ring isomerization to reach the ground state with essentially no fluorescence for o-HBDI or enhanced (up to an impressive 180-fold in acetonitrile) and solvent-polarity-dependent fluorescence by P-ring locking in o-LHBDI. The significant dependence of the fluorescence enhancement ratio on solvent viscosity confirms P-ring isomerization as the dominant nonradiative decay pathway for o-HBDI. This work provides crucial insights into the dynamic solute-solvent electrostatic and steric interactions, enabling the application-specific improvement of ESIPT-capable molecules as versatile fluorescence-based sensors and imaging agents from large Stokes shift emission to brighter probes in physiological environments.
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Affiliation(s)
- Sean A Boulanger
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
| | - Cheng Chen
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
| | - Ivan N Myasnyanko
- Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow 117997, Russia.,Pirogov Russian National Research Medical University, Ostrovitianov 1, Moscow 117997, Russia
| | - Mikhail S Baranov
- Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow 117997, Russia.,Pirogov Russian National Research Medical University, Ostrovitianov 1, Moscow 117997, Russia
| | - Chong Fang
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331, United States
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12
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Time-resolved infrared absorption spectroscopy applied to photoinduced reactions: how and why. Photochem Photobiol Sci 2022; 21:557-584. [DOI: 10.1007/s43630-022-00180-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 01/28/2022] [Indexed: 10/19/2022]
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13
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Uriarte LM, Vitale R, Niziński S, Hadjidemetriou K, Zala N, Lukacs A, Greetham GM, Sazanovich IV, Weik M, Ruckebusch C, Meech SR, Sliwa M. Structural Information about the trans-to- cis Isomerization Mechanism of the Photoswitchable Fluorescent Protein rsEGFP2 Revealed by Multiscale Infrared Transient Absorption. J Phys Chem Lett 2022; 13:1194-1202. [PMID: 35085441 DOI: 10.1021/acs.jpclett.1c02920] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
RsEGFP2 is a reversibly photoswitchable fluorescent protein used in super-resolved optical microscopies, which can be toggled between a fluorescent On state and a nonfluorescent Off state. Previous time-resolved ultraviolet-visible spectroscopic studies have shown that the Off-to-On photoactivation extends over the femto- to millisecond time scale and involves two picosecond lifetime excited states and four ground state intermediates, reflecting a trans-to-cis excited state isomerization, a millisecond deprotonation, and protein structural reorganizations. Femto- to millisecond time-resolved multiple-probe infrared spectroscopy (TRMPS-IR) can reveal structural aspects of intermediate species. Here we apply TRMPS-IR to rsEGFP2 and implement a Savitzky-Golay derivative analysis to correct for baseline drift. The results reveal that a subpicosecond twisted excited state precursor controls the trans-to-cis isomerization and the chromophore reaches its final position in the protein pocket within 100 ps. A new step with a time constant of 42 ns is reported and assigned to structural relaxation of the protein that occurs prior to the deprotonation of the chromophore on the millisecond time scale.
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Affiliation(s)
- Lucas M Uriarte
- Univ. Lille, CNRS, UMR 8516, LASIRE, Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France
| | - Raffaele Vitale
- Univ. Lille, CNRS, UMR 8516, LASIRE, Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France
| | - Stanisław Niziński
- Univ. Lille, CNRS, UMR 8516, LASIRE, Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France
- Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, Poznan 61-614, Poland
| | | | - Ninon Zala
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Andras Lukacs
- Department of Biophysics, Medical School, University of Pecs, Szigeti ut 12, 7624 Pecs, Hungary
| | - Gregory M Greetham
- Central Laser Facility, Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Igor V Sazanovich
- Central Laser Facility, Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Martin Weik
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Cyril Ruckebusch
- Univ. Lille, CNRS, UMR 8516, LASIRE, Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France
| | - Stephen R Meech
- School of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Michel Sliwa
- Univ. Lille, CNRS, UMR 8516, LASIRE, Laboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France
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14
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Li Y, Bai X, Liang R, Zhang X, Nguyen YH, VanVeller B, Du L, Phillips DL. Investigation of a Series of 2-(2'-Hydroxyaryl)benzazole Derivatives: Photophysical Properties, Excited-State Intramolecular Proton-Transfer Reactions, and Observation of Long-Lived Triplet Excited States. J Phys Chem B 2021; 125:12981-12989. [PMID: 34797676 DOI: 10.1021/acs.jpcb.1c05798] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Excited state intramolecular proton transfer (ESIPT) has drawn much attention for its important applications in a variety of areas. Here, the steady-state and time-resolved absorption spectroscopic experiments as well as DFT/TD-DFT calculations are employed to study the photophysical properties and photochemical reaction mechanisms of 2-(2'-hydroxyphenyl) benzoxazole (HBO) and selected derivatives (compounds 1-3). Because of their larger π-conjugation framework, compounds 1-3 display red-shifted absorbance but blue-shifted fluorescence compared with HBO. A fast ESIPT process is observed directly for HBO while compound 3 has an enol/keto equilibrium type of ESIPT that exhibits dual emission. Interestingly, only the emission of the enol form is observed for compounds 1 and 2 which suggests that the ESIPT process is strongly inhibited. These results indicate the decoration with electron-withdrawing groups such as thiadiazol and pyrazine on the hydroxyphenyl ring (compounds 1 and 2) apparently suppresses the proton-transfer processes in their excited states. Whereas the ESIPT process is rarely increased for compound 3 that modified with the phenanthrol ring, because the effective conjugation is reduced for compound 3 compared with HBO. The work here provides fundamental insights that may be useful for designing novel ESIPT molecules in the future.
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Affiliation(s)
- Yuanchun Li
- School of Life Sciences, Jiangsu University, Zhenjiang 212013, P.R. China.,Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
| | - Xueqin Bai
- Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
| | - Runhui Liang
- Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
| | - Xiting Zhang
- Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
| | - Yen H Nguyen
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Brett VanVeller
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Lili Du
- School of Life Sciences, Jiangsu University, Zhenjiang 212013, P.R. China.,Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong, Hong Kong, Hong Kong, S.A.R., P.R. China
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15
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Liu YH, Yu SB, Peng YJ, Wang CW, Zhu C, Lin SH. Excited-state intramolecular proton transfer with and without the assistance of vibronic-transition-induced skeletal deformation in phenol-quinoline. RSC Adv 2021; 11:37299-37306. [PMID: 35496430 PMCID: PMC9043822 DOI: 10.1039/d1ra07042h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/05/2021] [Indexed: 11/27/2022] Open
Abstract
The excited-state intramolecular proton transfer (ESIPT) reaction of two phenol-quinoline molecules (namely PQ-1 and PQ-2) were investigated using time-dependent density functional theory. The five-(six-) membered-ring carbocycle between the phenol and quinolone moieties in PQ-1 (PQ-2) actually causes a relatively loose (tight) hydrogen bond, which results in a small-barrier (barrier-less) on an excited-state potential energy surface with a slow (fast) ESIPT process with (without) involving the skeletal deformation motion up to the electronic excitation. The skeletal deformation motion that is induced from the largest vibronic excitation with low frequency can assist in decreasing the donor-acceptor distance and lowering the reaction barrier in the excited-state potential energy surface, and thus effectively enhance the ESIPT reaction for PQ-1. The Franck-Condon simulation indicated that the low-frequency mode with vibronic excitation 0 → 1' is an original source of the skeletal deformation vibration. The present simulation presents physical insights for phenol-quinoline molecules in which relatively tight or loose hydrogen bonds can influence the ESIPT reaction process with and without the assistance of the skeletal deformation motion.
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Affiliation(s)
- Yu-Hui Liu
- College of Physical Science and Technology, Bohai University Jinzhou 121013 China
| | - Shi-Bo Yu
- College of Physical Science and Technology, Bohai University Jinzhou 121013 China
| | - Ya-Jing Peng
- College of Physical Science and Technology, Bohai University Jinzhou 121013 China
| | - Chen-Wen Wang
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao-Tung University Hsinchu 30010 Taiwan
| | - Chaoyuan Zhu
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao-Tung University Hsinchu 30010 Taiwan
- Department of Applied Chemistry and Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University Hsinchu 30010 Taiwan
| | - Sheng-Hsien Lin
- Department of Applied Chemistry and Institute of Molecular Science, National Chiao-Tung University Hsinchu 30010 Taiwan
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16
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Kovács E, Cseri L, Jancsó A, Terényi F, Fülöp A, Rózsa B, Galbács G, Mucsi Z. Synthesis and Fluorescence Mechanism of the Aminoimidazolone Analogues of the Green Fluorescent Protein: Towards Advanced Dyes with Enhanced Stokes Shift, Quantum Yield and Two‐Photon Absorption. European J Org Chem 2021. [DOI: 10.1002/ejoc.202101173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Ervin Kovács
- Department of Chemistry Femtonics Inc. Tűzoltó u. 58 1094 Budapest Hungary
- Institute of Materials and Environmental Chemistry Research Centre for Natural Sciences Magyar tudósok körútja 2 1117 Budapest Hungary
| | - Levente Cseri
- Department of Chemistry Femtonics Inc. Tűzoltó u. 58 1094 Budapest Hungary
- Department of Chemical Engineering & Analytical Science The University of Manchester The Mill, Sackville Street Manchester M1 3BB United Kingdom
| | - Attila Jancsó
- Department of Inorganic and Analytical Chemistry University of Szeged Dóm tér 8 Szeged 6720 Hungary
| | - Ferenc Terényi
- Department of Inorganic and Analytical Chemistry University of Szeged Dóm tér 8 Szeged 6720 Hungary
| | - Anna Fülöp
- Department of Chemistry Femtonics Inc. Tűzoltó u. 58 1094 Budapest Hungary
| | - Balázs Rózsa
- Two-Photon Measurement Technology Research Group The Faculty of Information Technology Pázmány Péter Catholic University Práter u. 50/A Budapest 1083 Hungary
- Laboratory of 3D Functional Imaging of Neuronal Networks and Dendritic Integration Institute of Experimental Medicine Szigony utca 43 Budapest 1083 Hungary
| | - Gábor Galbács
- Department of Inorganic and Analytical Chemistry University of Szeged Dóm tér 8 Szeged 6720 Hungary
| | - Zoltán Mucsi
- Department of Chemistry Femtonics Inc. Tűzoltó u. 58 1094 Budapest Hungary
- Institute of Chemistry Faculty of Materials Science and Engineering University of Miskolc Egyetem út 1 Miskolc 3515 Hungary
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17
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Tao M, Wen L, Huo D, Kuang Z, Song D, Wan Y, Zhao H, Yan J, Xia A. Solvent Effect on Excited-State Intramolecular Proton-Coupled Charge Transfer Reaction in Two Seven-Membered Ring Pyrrole-Indole Hydrogen Bond Systems. J Phys Chem B 2021; 125:11275-11284. [PMID: 34587453 DOI: 10.1021/acs.jpcb.1c07438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the past decades, tremendous efforts have been invested into organic molecules involved in the excited-state intramolecular proton transfer (ESIPT) reaction due to their enormously Stokes-shifted fluorescence and distinctive photophysical properties. The alterations of the environmental medium can effectively adjust the luminous performance of ESIPT molecules, which inspires us to unravel the solvent effect on the ESIPT mechanism. Here, we report the solvent-dependent excited-state properties of two new seven-membered ring pyrrole-indole ESIPT molecules, g-PPDBI and e-PPDBI, by steady-state spectra, picosecond transient fluorescence spectra, femtosecond transient absorption spectra, and theoretical calculations. The bathochromic-shifted normal fluorescence and the negligibly shifted tautomer fluorescence suggest the occurrence of an excited-state intramolecular proton-coupled charge transfer reaction. Thus, the solvent effect plays a vital role in stabilizing the intramolecular charge transferred state, resulting in a higher ESIPT reaction barrier in more polar solvents. Additionally, the observation of the slight dynamic difference between PPDBIs with different π-conjugation positions provides a new strategy to adjust the performance of ESIPT molecules.
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Affiliation(s)
- Min Tao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Liu Wen
- College of Materials and Chemical Engineering, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, China Three Gorges University, Yichang 443002, Hubei, P. R. China
| | - Dayujia Huo
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Zhuoran Kuang
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Di Song
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Yan Wan
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Hongmei Zhao
- State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Jiaying Yan
- College of Materials and Chemical Engineering, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, China Three Gorges University, Yichang 443002, Hubei, P. R. China
| | - Andong Xia
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China.,State Key Laboratory of Information Photonic and Optical Communications, School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
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18
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Woodhouse JL, Henley A, Lewin R, Ward JM, Hailes HC, Bochenkova AV, Fielding HH. A photoelectron imaging study of the deprotonated GFP chromophore anion and RNA fluorescent tags. Phys Chem Chem Phys 2021; 23:19911-19922. [PMID: 34474467 DOI: 10.1039/d1cp01901e] [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
Green fluorescent protein (GFP), together with its family of variants, is the most widely used fluorescent protein for in vivo imaging. Numerous spectroscopic studies of the isolated GFP chromophore have been aimed at understanding the electronic properties of GFP. Here, we build on earlier work [A. V. Bochenkova, C. Mooney, M. A. Parkes, J. Woodhouse, L. Zhang, R. Lewin, J. M. Ward, H. Hailes, L. H. Andersen and H. H. Fielding, Chem. Sci., 2017, 8, 3154] investigating the impact of fluorine and methoxy substituents that have been employed to tune the electronic structure of the GFP chromophore for use as fluorescent RNA tags. We present photoelectron spectra following photoexcitation over a broad range of wavelengths (364-230 nm) together with photoelectron angular distributions following photoexcitation at 364 nm, which are interpreted with the aid of quantum chemistry calculations. The results support the earlier high-level quantum chemistry calculations that predicted how fluorine and methoxy substituents tune the electronic structure and we find evidence to suggest that the methoxy substituents enhance internal conversion, most likely from the 2ππ* state which has predominantly Feshbach resonance character, to the 1ππ* state.
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Affiliation(s)
- Joanne L Woodhouse
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Alice Henley
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Ross Lewin
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | - John M Ward
- The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Gower Street, London WC1E 6BT, UK
| | - Helen C Hailes
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
| | | | - Helen H Fielding
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
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19
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Jankowska J, Sobolewski AL. Modern Theoretical Approaches to Modeling the Excited-State Intramolecular Proton Transfer: An Overview. Molecules 2021; 26:molecules26175140. [PMID: 34500574 PMCID: PMC8434569 DOI: 10.3390/molecules26175140] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/20/2021] [Accepted: 08/23/2021] [Indexed: 02/02/2023] Open
Abstract
The excited-state intramolecular proton transfer (ESIPT) phenomenon is nowadays widely acknowledged to play a crucial role in many photobiological and photochemical processes. It is an extremely fast transformation, often taking place at sub-100 fs timescales. While its experimental characterization can be highly challenging, a rich manifold of theoretical approaches at different levels is nowadays available to support and guide experimental investigations. In this perspective, we summarize the state-of-the-art quantum-chemical methods, as well as molecular- and quantum-dynamics tools successfully applied in ESIPT process studies, focusing on a critical comparison of their specific properties.
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Affiliation(s)
- Joanna Jankowska
- Faculty of Chemistry, University of Warsaw, 02-093 Warsaw, Poland
- Correspondence:
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20
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Wang CH, Liu ZY, Huang CH, Chen CT, Meng FY, Liao YC, Liu YH, Chang CC, Li EY, Chou PT. Chapter Open for the Excited-State Intramolecular Thiol Proton Transfer in the Room-Temperature Solution. J Am Chem Soc 2021; 143:12715-12724. [PMID: 34355563 DOI: 10.1021/jacs.1c05602] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We report here, for the first time, the experimental observation on the excited-state intramolecular proton transfer (ESIPT) reaction of the thiol proton in room-temperature solution. This phenomenon is demonstrated by a derivative of 3-thiolflavone (3TF), namely, 2-(4-(diethylamino)phenyl)-3-mercapto-4H-chromen-4-one (3NTF), which possesses an -S-H···O═ intramolecular H-bond (denoted by the dashed line) and has an S1 absorption at 383 nm. Upon photoexcitation, 3NTF exhibits a distinctly red emission maximized at 710 nm in cyclohexane with an anomalously large Stokes shift of 12 230 cm-1. Upon methylation on the thiol group, 3MeNTF, lacking the thiol proton, exhibits a normal Stokes-shifted emission at 472 nm. These, in combination with the computational approaches, lead to the conclusion of thiol-type ESIPT unambiguously. Further time-resolved study renders an unresolvable (<180 fs) ESIPT rate for 3NTF, followed by a tautomer emission lifetime of 120 ps. In sharp contrast to 3NTF, both 3TF and 3-mercapto-2-(4-(trifluoromethyl)phenyl)-4H-chromen-4-one (3FTF) are non-emissive. Detailed computational approaches indicate that all studied thiols undergo thermally favorable ESIPT. However, once forming the proton-transferred tautomer, the lone-pair electrons on the sulfur atom brings non-negligible nπ* contribution to the S1' state (prime indicates the proton-transferred tautomer), for which the relaxation is dominated by the non-radiative deactivation. For 3NTF, the extension of π-electron delocalization by the diethylamino electron-donating group endows the S1' state primarily in the ππ* configuration, exhibiting the prominent tautomer emission. The results open a new chapter in the field of ESIPT, covering the non-canonical sulfur intramolecular H-bond and its associated ESIPT at ambient temperature.
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Affiliation(s)
- Chun-Hsiang Wang
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Zong-Ying Liu
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Chun-Hao Huang
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan (R.O.C.)
| | - Chao-Tsen Chen
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Fan-Yi Meng
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Yu-Chan Liao
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Yi-Hung Liu
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Chao-Che Chang
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
| | - Elise Y Li
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan (R.O.C.)
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.)
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21
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Liu ZY, Wei YC, Chou PT. Correlation between Kinetics and Thermodynamics for Excited-State Intramolecular Proton Transfer Reactions. J Phys Chem A 2021; 125:6611-6620. [PMID: 34308634 DOI: 10.1021/acs.jpca.1c04192] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Finding the relation between thermodynamics and kinetics for a reaction is of fundamental importance. Here, the thermodynamics and kinetics correlation of excited-state intramolecular proton transfer (ESIPT) was investigated by the TD-DFT calculation under the CAM-B3LYP/6-311+G** level. We choose the family 2-(2'-aminophyenyl)benzothiazole and its amino derivatives as paradigms, which all possess the NH-type intramolecular hydrogen bond (H-bond), and investigate the corresponding ESIPT reaction. The H-bond strength can be systematically tuned, so both activation energy ΔG‡ and free energy difference between proton transfer tautomer (T*, product) and normal species (N*, reactant) ΔGT*-N* can be varied. To minimize the environmental interference such as solvent external H-bond and polarity perturbation, a nonpolar solvent such as cyclohexane is chosen as a bath with a polarizable continuum solvation model for the calculation. As a result, the comprehensive computational approach reveals a linear relationship between ΔGT*-N* and ΔG‡, which can be expressed as ΔG‡ = ΔG0 + αΔGT*-N*. The fundamental insight is reminiscent of the Bell-Evans-Polanyi (BEP) principle where α represents the character of the position of the transition state along the proton motion coordinate. In other words, the more exergonic the ESIPT reaction is, the faster the proton transfer rate can be observed. To verify that such a correlation is not a sporadic event, another ESIPT family with an -OH proton, 1-hydroxy-11H-benzo[b]fluoren-11-one and its derivatives, was also investigated and proved to follow the BEP principle as well. Unlike the quantum mechanics description of proton transfer where either proton tunneling is dominant or solute/solvent is coupled in ESIPT, this work demonstrates that reaction kinetics and thermodynamics are strongly correlated within the same class of ESIPT molecules with an intrinsic barrier free from solvent perturbation, being faster with the more exergonic reaction.
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Affiliation(s)
- Zong-Ying Liu
- Department of Chemistry, National Taiwan University, Taipei, 10617 Taiwan, R.O.C
| | - Yu-Chen Wei
- Department of Chemistry, National Taiwan University, Taipei, 10617 Taiwan, R.O.C
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei, 10617 Taiwan, R.O.C
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22
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Zhang H, Li W, Wang Y, Tao Y, Wang Y, Yang F, Gao Z. Solvation effect on the ESIPT mechanism of nitrile-substituted ortho-hydroxy-2-phenyl-oxazolines. RSC Adv 2021; 11:25795-25800. [PMID: 35478890 PMCID: PMC9037208 DOI: 10.1039/d1ra04033b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 06/30/2021] [Indexed: 12/22/2022] Open
Abstract
In this study, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to unveil the solvation effects on the excited-state intramolecular proton transfer (ESIPT) of nitrile-substituted ortho-hydroxy-2-phenyl-oxazoline (NOHPO) molecules in three different solvents. According to the functional analysis of the reduced density gradient, hydrogen bond in low-polar solvents is stronger compared to that in high-polar solvents, indicating that proton transfer (PT) can be influenced by the polarity of the solvent. Moreover, the geometric parameters and infrared vibration spectrum of NOHPO in different types of solvents in the S0 and S1 state were compared, which confirmed the above results. By analyzing electronic spectra and frontier molecular orbitals, it was found that the spectral properties were affected by different polar solvents. Molecular electrostatic potential surface calculations proved that PT took place between the H2 atom and N3 atom, and the natural population analysis and Hirshfeld charge reveal the charge distribution after photoexcitation. To investigate the ESIPT progress intensively, the potential energy curves of NOHPO in three types of solvents were established. The findings revealed that NOHPO could transform from enol to keto form in the S1 state spontaneously, and ESIPT progress was promoted with the decrease in polarity.
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Affiliation(s)
- Hengwei Zhang
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
| | - Wenzhi Li
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
| | - Yuxi Wang
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
| | - Yaping Tao
- College of Physics and Electronic Information, Luoyang Normal University Luoyang 471022 P. R. China
| | - Yi Wang
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
| | - Fan Yang
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
| | - Ziqing Gao
- School of Biological Engineering, Dalian Polytechnic University Dalian 116034 P. R. China +86 0411 86323646 +86 0411 86323646
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23
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Luminescent excited-state intramolecular proton-transfer dyes based on 4-functionalized 6,6'-dimethyl-3,3'-dihydroxy-2,2'-bipyridine (BP(OH)2-Rs); DFT simulation study. J Mol Graph Model 2021; 107:107948. [PMID: 34082341 DOI: 10.1016/j.jmgm.2021.107948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/04/2021] [Accepted: 05/20/2021] [Indexed: 01/28/2023]
Abstract
The 4-functionalized 6,6'-dimethyl-3,3'-dihydroxy-2,2'-bipyridine dyes (BP(OH)2-Rs) have exhibited dienol and diketo emissions. The optimum geometrical structures for ground, singlet and triplet excited states are computed by DFT/B3LYP/6-31++G that showed the planarity of BP(OH)2-Rs structure. The emission spectra of the molecules are determined in the gas-phase at singlet and triplet excited states using CIS/6-31++G. The theoretical calculations are carried out for BP(OH)2-Rs to understand the impact of different substituents (R = -H (I), -Br (II), -TMS (III), -C2H (IV), -terpyridine (V) and -bodipy (diazaboraindacene) (VI)) on excited-state intramolecular proton transfer (ESIPT) in singlet and triplet excited states. Based on the calculations, the concerted diproton transfer proceeds in the triplet excited state, in which nπ* state has a significant participation in ESIPT. The spectral variation at ESIPT emission of BP(OH)2-Rs is influenced by the electron-acceptor ability of the substituents. The compound V revealed a higher spectral intensity compared to the others. From the comparison with the experimental data, the molecule V is almost planar agreed with the X-ray structure and trend variation of wavelengths. The molecule VI contains bodipy chromophore that excitation energy transfers completely from BP(OH)2 core to a bodipy substituent, leading to emission from the lowest-lying bodipy substituent, and consequently, ESIPT does not occur for this dye.
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24
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Cao B, Li Y, Zhou Q, Li B, Su X, Yin H, Shi Y. Synergistically improving myricetin ESIPT and antioxidant activity via dexterously trimming atomic electronegativity. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.115272] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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25
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Kong J, Wang Y, Qi W, Huang M, Su R, He Z. Green fluorescent protein inspired fluorophores. Adv Colloid Interface Sci 2020; 285:102286. [PMID: 33164780 DOI: 10.1016/j.cis.2020.102286] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 10/11/2020] [Accepted: 10/12/2020] [Indexed: 12/20/2022]
Abstract
Green fluorescence proteins (GFP) are appealing to a variety of biomedical and biotechnology applications, such as protein fusion, subcellular localizations, cell visualization, protein-protein interaction, and genetically encoded sensors. To mimic the fluorescence of GFP, various compounds, such as GFP chromophores analogs, hydrogen bond-rich proteins, and aromatic peptidyl nanostructures that preclude free rotation of the aryl-alkene bond, have been developed to adapt them for a fantastic range of applications. Herein, we firstly summarize the structure and luminescent mechanism of GFP. Based on this, the design strategy, fluorescent properties, and the advanced applications of GFP-inspired fluorophores are then carefully discussed. The diverse advantages of bioinspired fluorophores, such as biocompatibility, structural simplicity, and capacity to form a variety of functional nanostructures, endow them potential candidates as the next-generation bio-organic optical materials.
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26
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Liu ZY, Hu JW, Huang TH, Chen KY, Chou PT. Excited-state intramolecular proton transfer in the kinetic-control regime. Phys Chem Chem Phys 2020; 22:22271-22278. [PMID: 33001109 DOI: 10.1039/d0cp03408h] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A new series of molecules bearing a 2,11-dihydro-1H-cyclopenta[de]indeno[1,2-b]quinoline (CPIQ) chromophore with the N-HN type of intramolecular hydrogen bond are strategically designed and synthesized, among which CPIQ-OH, CPIQ-NHAc and CPIQ-NHTs in solution exhibit a single emission band with an anomalously large Stokes shift, whereas CPIQ-NH2 and CPIQ-NHMe show apparent dual-emission property. This, in combination with time-resolved spectroscopy and the computational approach, leads us to conclude that CPIQ-OH, CPIQ-NHAc and CPIQ-NHTs undergo ultrafast, highly exergonic excited-state intramolecular proton transfer (ESIPT), while a finite rate of ESIPT is observed for CPIQ-NH2 and CPIQ-NHMe with a time constant of 117 ps and 39 ps, respectively, in acetonitrile at room-temperature. Further temperature-dependent studies deduce an appreciable ESIPT barrier for CPIQ-NH2 and CPIQ-NHMe. Different from most of the barrier associated ESIPT molecules that are commonly in the thermodynamic-control regime, i.e. found in the thermal pre-equilibrium between excited normal and proton-transfer tautomer states, CPIQ-NH2 and CPIQ-NHMe cases are in the kinetic-control regime where ESIPT is irreversible with a significant barrier. The barrier is able to be tuned by the electronic properties of the -R group in the NR-H proton donor site, resulting in ratiometric fluorescence for normal versus tautomer emission.
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Affiliation(s)
- Zong-Ying Liu
- Department of Chemistry, National Taiwan University, Taipei, 10617 Taiwan, Republic of China.
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Skillfully tuning 1-hydroxy-9H-fluoren-9-one forward-backward ESIPT processes by introducing electron-withdrawing groups: A theoretical exploration. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112627] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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28
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Sensing mechanism of a ratiometric near-infrared fluorescent chemosensor for cysteine hydropersulfide: Intramolecular charge transfer. Sci Rep 2020; 10:711. [PMID: 31959854 PMCID: PMC6971067 DOI: 10.1038/s41598-020-57631-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 12/21/2019] [Indexed: 11/09/2022] Open
Abstract
Previous studies have shown that the cysteine hydropersulfide (Cys-SSH) as the sulfur donor is crucial to sulfur-containing cofactors synthesis. Recently, a selective and sensitive near-infrared ratiometric fluorescent chemosensor Cy-DiSe has been designed and synthesized to detect Cys-SSH spontaneously. Herein, by means of the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) approaches, the sensing mechanism has been thoroughly explored. According to our calculations, the experimental data have been reproduced. The results indicate the intramolecular charge transfer (ICT) is the reason for changes in fluorescence wavelengths. Compared with the chemosensor Cy-DiSe, the larger energy gap of Cy induced by ICT mechanism leads to the blue-shift of the absorption and emission spectra, which guarantees that Cy-DiSe can become a ratiometric fluorescent chemosensor to detect Cys-SSH.
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29
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Chatterjee S, Ahire K, Karuso P. Room-Temperature Dual Fluorescence of a Locked Green Fluorescent Protein Chromophore Analogue. J Am Chem Soc 2019; 142:738-749. [PMID: 31846319 DOI: 10.1021/jacs.9b05096] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A structurally locked green fluorescent protein (GFP) chromophore with a phenyl group at C(2) of the imidazolone has been synthesized. Rotation around the exocyclic double bond is hindered, resulting in room-temperature fluorescence. The quantum yield in water is 500 times greater than that of unlocked analogues. Unlike the methyl-substituted analogue, the phenyl analogue exhibits a dual emission (cyan and red) that can be used for ultrasensitive ratiometric measurements and fluorescence microscopy. To explain this dual emission, DFT calculations were carried out along with fluorescence upconversion experiments. The Z-isomer was found to be emissive, while the origin of the dual emission was dependent on the phenyl group in the Z-isomer, which stabilizes the Franck-Condon state, resulting in a cyan fluorescence, while the zwitterionic tautomer fluoresces red. These results bring important new insights into the photophysics of the GFP chromophore and provide a new scaffold capable of dual emission with utility in biotechnology.
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Affiliation(s)
- Soumit Chatterjee
- Department of Molecular Sciences , Macquarie University , Sydney , NSW 2109 , Australia
| | - Ketan Ahire
- Department of Molecular Sciences , Macquarie University , Sydney , NSW 2109 , Australia
| | - Peter Karuso
- Department of Molecular Sciences , Macquarie University , Sydney , NSW 2109 , Australia
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30
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Zhang N, Wen L, Yan J, Liu G, Zhang T, Wang Y, Liu X. A facile synthesis of seven-membered N, O-ligands and their optical properties. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.07.108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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31
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Ni M, Su S, Fang H. Excited state intramolecular proton transfer via different size of hydrogen bond ring: a theoretical insight. Theor Chem Acc 2019. [DOI: 10.1007/s00214-019-2512-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Yu B, Liu D, Zhang J, Li Z, Zhang YM, Li M, Zhang SXA. Emissions and the application of a series of twisted fluorophores with intramolecular weak hydrogen bonds. RSC Adv 2019; 9:13214-13219. [PMID: 35520777 PMCID: PMC9063768 DOI: 10.1039/c9ra01244c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/15/2019] [Indexed: 01/30/2023] Open
Abstract
A series of twisted fluorophores of CEOCH (((2,5-dimethoxy-1,4-phenylene)bis(ethene-2,1,1-triyl))-tetra-benzene) derivatives with intramolecular weak hydrogen bonds (IMWHBs) were synthesized to investigate how different substituents on outer benzenes influence their emissive properties. Because of the twisted structure and weak intermolecular interactions, the emissions of the CEOCH derivatives were intense in the aggregated state but as the flexibility and electronic effect of the substituents changed, their quantum yields (QYs) changed from over 40% to 1% in solution. Based on the adjustable QYs of CEOCHs with different substituents in solutions, a fluorescent sensor for hydrazine with an extremely strong light and dark contrast was obtained via the conversion of dicyanovinyl groups to hydrazone groups.
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Affiliation(s)
- Binhong Yu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 PR China .,College of Chemistry, Jilin University Changchun 130012 PR China
| | - Danyang Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 PR China .,College of Chemistry, Jilin University Changchun 130012 PR China
| | - Jinyan Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 PR China .,College of Chemistry, Jilin University Changchun 130012 PR China
| | - Zhize Li
- College of Chemistry, Jilin University Changchun 130012 PR China
| | - Yu-Mo Zhang
- College of Chemistry, Jilin University Changchun 130012 PR China
| | - Minjie Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 PR China .,College of Chemistry, Jilin University Changchun 130012 PR China
| | - Sean Xiao-An Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 PR China .,College of Chemistry, Jilin University Changchun 130012 PR China
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Singh A, Samanta D, Boro M, Maji TK. Gfp chromophore integrated conjugated microporous polymers: topological and ESPT effects on emission properties. Chem Commun (Camb) 2019; 55:2837-2840. [PMID: 30768086 DOI: 10.1039/c9cc00357f] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A metal free topological approach is demonstrated to mimic the photophysical properties of natural gfp by synthesizing two gfp chromophore integrated conjugated microporous polymers (o-HBDI-TEB-CMP and o-MBDI-TEB-CMP). Interestingly, owing to the structural rigidity, the emission (λem = 515 nm) and excited state lifetime (4.1 ns) of hydroxy substituted o-HBDI-TEB-CMP are found to be similar to the natural gfp. The crucial role of the -OH group for the green emission is further supported by -OMe substituted o-MBDI-TEB-CMP (λem = 440 nm) and also validated theoretically.
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Affiliation(s)
- Ashish Singh
- Molecular Materials Laboratory, Chemistry and Physics of Materials Unit, School of Advanced Materials (SAMat), Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore-560064, India.
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Lei YQ, Xi JY, Guo H, Jia R. DFT/TDDFT methods analysis of ESIPT process in a series of 7-hydroxy-1-indanone derivates and new dyad design. JOURNAL OF SAUDI CHEMICAL SOCIETY 2018. [DOI: 10.1016/j.jscs.2017.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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35
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Yu B, Liu D, Wang Y, Zhang T, Zhang YM, Li M, Zhang SXA. Strong and insusceptible photo-emissions from an intramolecular weak hydrogen bond strengthened twisted fluorophore. Phys Chem Chem Phys 2018; 20:23851-23855. [PMID: 30211408 DOI: 10.1039/c8cp04242j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Intramolecular weak hydrogen bonds of CHO and CH/Pi were introduced into a twisted fluorophore backbone of 1,4-bis(2,2-diphenylvinyl)benzene, which enables the fluorophore to emit violently and stably in both solubilized and aggregated states, and be inert to solvent environments and preserve over 10% quantum yield at temperature as high as 90 °C in solution.
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Affiliation(s)
- Binhong Yu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry Jilin University, Changchun 130012, P. R. China.
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36
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Kuang Z, Guo Q, Wang X, Song H, Maroncelli M, Xia A. Ultrafast Ground-State Intramolecular Proton Transfer in Diethylaminohydroxyflavone Resolved with Pump-Dump-Probe Spectroscopy. J Phys Chem Lett 2018; 9:4174-4181. [PMID: 29991264 DOI: 10.1021/acs.jpclett.8b01826] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
4'- N, N-Diethylamino-3-hydroxyflavone (DEAHF), due to excited-state intramolecular proton transfer (ESIPT) reaction, exhibits two solvent-dependent emission bands. Because of the slow formation and fast decay of the ground-state tautomer, its population does not accumulate enough for its detection during the normal photocycle. As a result, the details of the ground-state intramolecular proton-transfer (GSIPT) reaction have remained unknown. The present work uses femtosecond pump-dump-probe spectroscopy to prepare the short-lived ground-state tautomer and track this GSIPT process in solution. By simultaneously measuring femtosecond pump-probe and pump-dump-probe spectra, ultrafast kinetics of the ESIPT and GSIPT reactions are obtained. The GSIPT reaction is shown to be a solvent-dependent irreversible two-state process in two solvents, with estimated time constants of 1.7 ps in toluene and 10 ps in the more polar tetrahydrofuran. These results are of great value in both fully describing the photocycle of this four-level proton transfer molecule and for providing a deeper understanding of dynamical solvent effects on tautomerization.
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Affiliation(s)
- Zhuoran Kuang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Qianjin Guo
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China
| | - Xian Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Hongwei Song
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Mark Maroncelli
- Department of Chemistry , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - Andong Xia
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
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37
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38
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Chen YH, Sung R, Sung K. Insights into Excited State Intramolecular Proton Transfer: An Alternative Model for Excited State Proton Transfer of Green Fluorescence Protein. J Phys Chem A 2018; 122:5931-5944. [DOI: 10.1021/acs.jpca.8b01799] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Yi-Hui Chen
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - Robert Sung
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
| | - Kuangsen Sung
- Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
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39
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Wu K, Zhang T, Wang Z, Wang L, Zhan L, Gong S, Zhong C, Lu ZH, Zhang S, Yang C. De Novo Design of Excited-State Intramolecular Proton Transfer Emitters via a Thermally Activated Delayed Fluorescence Channel. J Am Chem Soc 2018; 140:8877-8886. [DOI: 10.1021/jacs.8b04795] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Kailong Wu
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
- Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, People’s Republic of China
| | - Tao Zhang
- Department of Physics, Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091, People’s Republic of China
| | - Zian Wang
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Lian Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People’s Republic of China
| | - Lisi Zhan
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Shaolong Gong
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Cheng Zhong
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Zheng-Hong Lu
- Department of Physics, Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming 650091, People’s Republic of China
| | - Song Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People’s Republic of China
| | - Chuluo Yang
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, People’s Republic of China
- Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, People’s Republic of China
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40
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A Theoretical Investigation About the Excited State Dynamical Mechanism for Doxorubicin Sensor. J CLUST SCI 2018. [DOI: 10.1007/s10876-018-1388-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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41
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Singh A, Badi-Uz-Zama K, Ramanathan G. Protonation of the imino nitrogen deactivates the excited state of imidazolin-5-one in the solid state. J CHEM SCI 2018. [DOI: 10.1007/s12039-018-1429-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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42
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Yuan H, Feng S, Wen K, Guo X, Zhang J. The excited-state intramolecular proton transfer in NH-type dye molecules with a seven-membered-ring intramolecular hydrogen bond: A theoretical insight. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 191:421-426. [PMID: 29069638 DOI: 10.1016/j.saa.2017.10.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/09/2017] [Accepted: 10/15/2017] [Indexed: 06/07/2023]
Abstract
Excited-state intramolecular proton transfer (ESIPT) reactions of a series of N(R)H⋯N-type seven-membered-ring hydrogen-bonding compounds were explored by employing density functional theory/time-dependent density functional theory calculations with the PBE0 functional. Our results indicate that the absorption and emission spectra predicted theoretically match very well the experimental findings. Additionally, as the electron-withdrawing strength of R increases, the intramolecular H-bond of the NS1 form gradually enhances, and the forward energy barrier along the ESIPT reaction gradually decreases. For compound 4, its ESIPT reaction is found to be a barrierless process due to the involvement of a strong electron-withdrawing COCF3 group. It is therefore a reasonable presumption that the ESIPT efficiency of these N(R)H⋯N-type seven-membered-ring H-bonding systems can be improved when a strong electron-withdrawing group in R is introduced.
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Affiliation(s)
- Huijuan Yuan
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, PR China
| | - Songyan Feng
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, PR China
| | - Keke Wen
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, PR China
| | - Xugeng Guo
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, PR China.
| | - Jinglai Zhang
- College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, PR China.
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Gao A, Li J, Wang D, Ma X, Wang M. Nonadiabatic dynamics simulation of photoisomerization mechanism of the second stablest isomer of N-salicilydenemethylfurylamine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 191:315-324. [PMID: 29055276 DOI: 10.1016/j.saa.2017.10.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/07/2017] [Accepted: 10/12/2017] [Indexed: 06/07/2023]
Abstract
The photoisomerization processes of the second stablest isomer in the aromatic Schiff base, N-salicilydenemethylfurylamine, in the gas phase have been studied by static electronic structure calculations and surface-hopping dynamics simulations based on the Zhu-Nakamura theory. Various stable structures are obtained in the optimization because of different orientations of methyl-furyl part with respect to the salicylaldimine part and different orientations of hydroxy group with respect to the benzene ring. Upon photoexcitation into the first excited state, bond isomerization in the salicylaldimine part is completely suppressed until the strong excited-state hydrogen bond is broken. The decay pathway involves two excited-state minima, one in cis-enol form and the other in cis-keto form. After the excited-state proton transfer, twists of bonds lead to a conical intersection between the ground and excited states. After internal conversion around a conical intersection, the molecule is stabilized in cis- or trans-keto form. If the reverse hydrogen transfer process occurs in the ground state, the molecule will finally end up in the cis-enol region. The cis-keto and trans-keto isomers are observed as photoproducts. According to our full-dimensional nonadiabatic dynamics simulations, we find the excited-state intramolecular proton transfer and torsions of three single bonds in the chain to be responsible for photoisomerization of the second stablest isomer of N-salicilydenemethylfurylamine.
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Affiliation(s)
- Aihua Gao
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China.
| | - Jianpeng Li
- Technical Test Center, Shengli Oil-field, Sinopec, Dongying 257000, China
| | - Dehua Wang
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China
| | - Xiaoguang Ma
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China
| | - Meishan Wang
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China.
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Dommett M, Crespo-Otero R. Excited state proton transfer in 2'-hydroxychalcone derivatives. Phys Chem Chem Phys 2018; 19:2409-2416. [PMID: 28058421 DOI: 10.1039/c6cp07541j] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fluorophores exhibiting excited-state intramolecular proton transfer (ESIPT) are promising candidates for applications ranging from imaging and probing to laser dyes, optoelectronic devices and molecular logic gates. Recently, ESIPT-active solid-state emitters based on 2'-hydroxychalcone have been synthesized. The compounds are almost non-emissive in solution but emit in the deep red/NIR region when crystalline. Herein, we present a comprehensive theoretical investigation of the gas-phase excited state relaxation pathways in five 2'-hydroxychalcone systems, using a combination of static and non-adiabatic simulations. We identify two competing non-radiative relaxation channels, driven by intramolecular rotation in the enol and keto excited states. Both mechanisms are accessible for the five compounds studied and their relative population depends on the nature of the substituent. The addition of electron-donating substituents greatly increases the propensity of the ESIPT pathway versus rotation in the enol state. The identification of the fundamental relaxation mechanisms is the first step towards understanding the aggregated emission phonomena of these compounds.
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Affiliation(s)
- Michael Dommett
- School of Biological and Chemical Sciences, Materials Research Institute, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| | - Rachel Crespo-Otero
- School of Biological and Chemical Sciences, Materials Research Institute, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
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45
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Wineman-Fisher V, Simkovich R, Huppert D, Trujillo K, Remington SJ, Miller Y. Mutagenic induction of an ultra-fast water-chain proton wire. Phys Chem Chem Phys 2018; 18:23089-95. [PMID: 27492977 DOI: 10.1039/c6cp05071a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Replacement of the hydroxyl group of a hydrophilic sidechain by an H atom in the proton wire of GFP induces formation of a water-chain proton wire. Surprisingly, this "non-native" water chain functions as a proton wire with response times within 10 ps of the wild type protein. This remarkable rate retention is understood as a natural consequence of the well-known Grotthuss mechanism of proton transfer in water.
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Affiliation(s)
- Vered Wineman-Fisher
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel. and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beér-Sheva 84105, Israel
| | - Ron Simkovich
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel
| | - Dan Huppert
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel
| | - Kristina Trujillo
- Department of Physics and Institute of Molecular Biology, University of Oregon, Eugene, USA
| | - S James Remington
- Department of Physics and Institute of Molecular Biology, University of Oregon, Eugene, USA
| | - Yifat Miller
- Department of Chemistry, Ben-Gurion University of the Negev, P.O. Box 653, Be'er Sheva 84105, Israel. and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beér-Sheva 84105, Israel
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46
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Guo WW, Fang YG, Fang Q, Cui GL. Mechanistic Insights into the Photophysics of Ortho-hydroxyl GFP Core Chromophores. CHINESE J CHEM PHYS 2017. [DOI: 10.1063/1674-0068/30/cjcp1709179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Wei-wei Guo
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Ye-guang Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Qiu Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Gang-long Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
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47
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Meng FY, Hsu YH, Zhang Z, Wu PJ, Chen YT, Chen YA, Chen CL, Chao CM, Liu KM, Chou PT. The Quest of Excited-State Intramolecular Proton Transfer via Eight-Membered Ring π-Conjugated Hydrogen Bonding System. Chem Asian J 2017; 12:3010-3015. [PMID: 28980416 DOI: 10.1002/asia.201701057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/02/2017] [Indexed: 11/05/2022]
Abstract
Searching for eight-membered ring π-conjugated hydrogen bonding (8-MR H-bonding) systems with excited-state intramolecular proton transfer (ESIPT) property is seminal and synthetically challenging. In this work, a series of π-conjugated molecules (8-HB-1, 8-HB-L1 and 8-HB-2) potentially possessing 8-MR H-bonding are strategically designed, synthesized and characterized. The configurations of these three potential molecules are checked by their X-ray structures, among which 8-HB-L1 (a structurally locked 8-HB-1 core chromophore) is proved to be an 8-MR H-bonding system, whereas 8-HB-1 and 8-HB-2 are too sterically hindered to form the 8-MR intramolecular H-bond. The ESIPT property of 8-HB-L1 is confirmed by the dual fluorescence consisting of normal and proton-transfer tautomer emissions. The insight into the ESIPT process of 8-HB-L1 is provided by femtosecond fluorescence upconversion measurements together with computational simulation. The results demonstrate for the first time a successful synthetic route to attain the 8-MR H-bonding molecule 8-HB-L1 with ESIPT property.
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Affiliation(s)
- Fan-Yi Meng
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Yen-Hao Hsu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Zhiyun Zhang
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Pei-Jhen Wu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Yi-Ting Chen
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Yi-An Chen
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Chi-Lin Chen
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
| | - Chi-Min Chao
- Department of Medical Applied Chemistry, Department of Medical Education, Chung Shan Medical University, Taichung, 40201, Taiwan, R.O.C
| | - Kuan-Miao Liu
- Department of Medical Applied Chemistry, Department of Medical Education, Chung Shan Medical University, Taichung, 40201, Taiwan, R.O.C
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, R.O.C
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48
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Tsai MS, Ou CL, Tsai CJ, Huang YC, Cheng YC, Sun SS, Yang JS. Fluorescence Enhancement of Unconstrained GFP Chromophore Analogues Based on the Push–Pull Substituent Effect. J Org Chem 2017; 82:8031-8039. [DOI: 10.1021/acs.joc.7b01260] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Meng-Shiue Tsai
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
- Institute
of Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Chun-Lin Ou
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Chi-Jui Tsai
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Yen-Chin Huang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Yuan-Chung Cheng
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Shih-Sheng Sun
- Institute
of Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Jye-Shane Yang
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
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49
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Lee G, Kim J, Kim SY, Kim DE, Joo T. Vibrational Spectrum of an Excited State and Huang-Rhys Factors by Coherent Wave Packets in Time-Resolved Fluorescence Spectroscopy. Chemphyschem 2017; 18:670-676. [DOI: 10.1002/cphc.201601295] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/05/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Gyeongjin Lee
- Department of Chemistry; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
| | - Junwoo Kim
- Department of Chemistry; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
| | - So Young Kim
- Department of Chemistry; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
| | - Dong Eon Kim
- Physics Department, Center for Attosecond Science and Technology, and Max Planck Center for Attosecond Science; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
| | - Taiha Joo
- Department of Chemistry; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
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50
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McLaughlin C, Assmann M, Parkes MA, Woodhouse JL, Lewin R, Hailes HC, Worth GA, Fielding HH. ortho and para chromophores of green fluorescent protein: controlling electron emission and internal conversion. Chem Sci 2017; 8:1621-1630. [PMID: 29780449 PMCID: PMC5933426 DOI: 10.1039/c6sc03833f] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 11/05/2016] [Indexed: 12/22/2022] Open
Abstract
Green fluorescent protein (GFP) continues to play an important role in the biological and biochemical sciences as an efficient fluorescent probe and is also known to undergo light-induced redox transformations. Here, we employ photoelectron spectroscopy and quantum chemistry calculations to investigate how the phenoxide moiety controls the competition between electron emission and internal conversion in the isolated GFP chromophore anion, following photoexcitation with ultraviolet light in the range 400-230 nm. We find that moving the phenoxide group from the para position to the ortho position enhances internal conversion back to the ground electronic state but that adding an additional OH group to the para chromophore, at the ortho position, impedes internal conversion. Guided by quantum chemistry calculations, we interpret these observations in terms of torsions around the C-C-C bridge being enhanced by electrostatic repulsions or impeded by the formation of a hydrogen-bonded seven-membered ring. We also find that moving the phenoxide group from the para position to the ortho position reduces the energy required for detachment processes, whereas adding an additional OH group to the para chromophore at the ortho position increases the energy required for detachment processes. These results have potential applications in tuning light-induced redox processes of this biologically and technologically important fluorescent protein.
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Affiliation(s)
- Conor McLaughlin
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Mariana Assmann
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Michael A Parkes
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Joanne L Woodhouse
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Ross Lewin
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Helen C Hailes
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Graham A Worth
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
| | - Helen H Fielding
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , UK .
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