Understanding the variable fluorescence quantum yield of tryptophan in proteins using QM-MM simulations. Quenching by charge transfer to the peptide backbone

2003 ◽  
Vol 369 (3-4) ◽  
pp. 409-414 ◽  
Author(s):  
Patrik R. Callis ◽  
James T. Vivian
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Variable Fluorescence ◽  
Peptide Backbone

scholarly journals Fluorescence quantum yield rationalized by the magnitude of the charge transfer in π-conjugated terpyridine derivatives

2016 ◽  
Vol 18 (42) ◽  
pp. 29387-29394 ◽  
Author(s):  
Marie Humbert-Droz ◽  
Claude Piguet ◽  
Tomasz A. Wesolowski
Keyword(s):  
Dipole Moment ◽  
Charge Transfer ◽  
Quantum Yield ◽  
Excited States ◽  
Charge Separation ◽  
Fluorescence Quantum Yield ◽  
Molecular Design ◽  
Electron Hole ◽  
Two Measures

Two measures of charge separation in ground and excited states (length of the change in dipole moment and the electron–hole distance) provide a remarkable tool for the molecular design of a fluorescent polyaromatic antenna.

Spin-Bahn-Kopplungseffekte in nicht-ebenen Biarylen / Spin-orbit Coupling Effects in Non-planar Biaryls

1977 ◽  
Vol 32 (3-4) ◽  
pp. 339-340 ◽  
Author(s):  
M. Zander
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Transition Probability ◽  
Heavy Atom ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Coupling Effects ◽  
Triplet Formation

Abstract The non-planar biaryls 2,2′-dimethyl-biphenyl, 1,1′-bi-naphthyl and 9,9′-biphenanthryl have higher phosphorescence/fluorescence quantum yield ratios than biphenyl, naphthalene and phenanthrene respectively. The increase of spin-orbit coupling in 1,1′-binaphthyl in comparison to naphthalene results in an increase of the phosphorescence transition probability while the triplet formation quantum yield is not enhanced. The much weaker effect of an external heavy atom pertuber on the spin-forbidden electronic tran­ sition rate probabilities in the case of 1,1′-binaphthyl in comparison to naphthalene is explained on the basis of a weaker charge-transfer interaction between luminescer and pertuber in the case of binaphthyl.

scholarly journals Novel turn-on fluorescent sensor for cyanide ion based on the charge transfer transition of phenothiazine/indolium compounds

2021 ◽  
Author(s):  
Yasuhiro Morikawa ◽  
Miku Hirabara ◽  
Keiji Nishiwaki ◽  
Shigeo Suzuki ◽  
Isao Nakanishi
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Fluorescent Sensor ◽  
Stokes Shift ◽  
Charge Transfer Transition ◽  
Cyanide Ion ◽  
Large Stokes Shift ◽  
Turn On

A new fluorescent sensor combining phenothiazine and indolium, which reacts specifically with the cyanide ion with a large Stokes shift and a good fluorescence quantum yield, was prepared. When CN-.

scholarly journals Binding Modes of a Phenylpyridinium Styryl Fluorescent Dye with Cucurbiturils

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5111
Author(s):  
Adrien Paudics ◽  
Dóra Hessz ◽  
Márton Bojtár ◽  
Benjámin Gyarmati ◽  
András Szilágyi ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Polyethylene Glycol ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Phenyl Ring ◽  
Intramolecular Charge Transfer ◽  
Theoretical Calculations ◽  
Binding Modes ◽  
Pyridinium Ring ◽  
Solvatochromic Dye

In order to explore how cucurbituril hosts accommodate an N-phenyl-pyridinium derivative guest, the complexation of the solvatochromic dye, 4-(4-(dimethylamino)styryl)-1-phenylpyridinium iodide (PhSt) with α,α′,δ,δ′-tetramethyl-cucurbit[6]uril (Me4CB6) and cucurbit[7]uril (CB7) was investigated by absorption spectroscopic, fluorescence and NMR experiments. In aqueous solutions, PhSt forms 1:1 complexes with both cucurbiturils, the complex with CB7 has a higher stability constant (Ka = 6.0 × 106 M−1) than the complex with Me4CB6 (Ka = 1.1 × 106 M−1). As revealed by NMR experiments and confirmed by theoretical calculations, CB7 encapsulates the whole phenylpyridinium entity of the PhSt cation guest, whereas the cavity of Me4CB6 includes only the phenyl ring, the pyridinium ring is bound to the carbonyl rim of the host. The binding of PhSt to cucurbiturils is accompanied by a strong enhancement of the fluorescence quantum yield due to the blocking of the deactivation through a twisted intramolecular charge transfer (TICT) state. The TICT mechanism in PhSt was characterized by fluorescence experiments in polyethylene glycol (PEG) solvents of different viscosities. The PhSt-CB7 system was tested as a fluorescence indicator displacement (FID) assay, and it recognized trimethyl-lysine selectively over other lysine derivatives.

THE EFFECT OF DIMETHYLSULFOXIDE ON THE FLUORESCENCE PROPERTIES OF SOME 4-HYDROXYQUINOLINES

2021 ◽  
Vol 55 (2 (255)) ◽  
pp. 112-117
Author(s):  
Karine R. Grigoryan ◽  
Hasmik A. Shilajyan ◽  
Iskuhi L. Aleksanyan ◽  
Zara L. Grigoryan ◽  
Lilit P. Hambardzumyan
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Aqueous Solutions ◽  
Electron Density ◽  
Aromatic Ring ◽  
Fluorescence Quantum Yield ◽  
Tautomeric Equilibrium ◽  
Fluorescence Properties ◽  
Fluorescence Efficiency ◽  
Dmso Concentration

Fluorescence properties of 4-hydroxy-2-methylquinoline (1) and 2-(5-mercapto-1,3,4-oxadiazol-2-yl)-6-methylquinoline-4-ol (2) were studied in dimethylsulfoxide (DMSO) aqueous solutions. The fluorescence properties of 1 and 2 exhibit substantial dependence on the DMSO concentration. The fluorescence quantum yield $(\Phi_f)$ of 1 decreases upon adding DMSO due to the shift in the keto-enol (E) tautomeric equilibrium toward E form․ On the contrary 2 demonstrates a tendency of increase of $\Phi_f$ upon adding DMSO due to intermolecular charge transfer from DMSO to the aromatic ring of quinoline, which increases the electron density on the ring and hence the fluorescence efficiency.

scholarly journals Synthesis of carbon nitride oligomer as a precursor of melon with improved fluorescence quantum yield

2021 ◽  
Vol 2 (18) ◽  
pp. 6083-6093
Author(s):  
Yuto Miyake ◽  
Goichiro Seo ◽  
Kotaro Matsuhashi ◽  
Noriyuki Takada ◽  
Kaname Kanai
Keyword(s):  
Optical Properties ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Carbon Nitride

Melem tetramer, the newly synthesized carbon nitride compound is composed of oligomers with four melem units, is stable in air, and has improved optical properties compared to melon.

scholarly journals Modulation of charge transfer by N-alkylation to control photoluminescence energy and quantum yield

2020 ◽  
Vol 11 (27) ◽  
pp. 6990-6995 ◽  
Author(s):  
Andrew T. Turley ◽  
Andrew Danos ◽  
Antonio Prlj ◽  
Andrew P. Monkman ◽  
Basile F. E. Curchod ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Excited States

A versatile N-alkylation strategy controls the presence of charge-transfer excited states and the emission colour of N-heterocyclic chromophores.

UV-Trained and Metal-Enhanced Fluorescence of Biliverdin and Biliverdin Nanoparticles

Nanoscale ◽  
2021 ◽  
Author(s):  
Parinaz Fathi ◽  
Ayman Roslend ◽  
Kritika Mehta ◽  
Parikshit Moitra ◽  
Kai Zhang ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Biomedical Imaging ◽  
Enhanced Fluorescence ◽  
Metal Enhanced Fluorescence

Increasing the fluorescence quantum yield of fluorophores is of great interest for in vitro and in vivo biomedical imaging applications. At the same time, photobleaching and photodegradation resulting from continuous...

Internal Conversion with 3,5-Dimethyl-4-(methylamino)benzonitrile in Alkane Solvents

2000 ◽  
Vol 214 (11) ◽  
Author(s):  
I. Rückert ◽  
A. Hebecker ◽  
A.B.J. Parusel ◽  
K.A. Zachariasse
Keyword(s):  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Internal Conversion ◽  
Alkane Solvents

With 3,5-dimethyl-4-(methylamino)benzonitrile (MHD) in n-hexane and n-hexadecane at 25°C, relatively small values are obtained for the fluorescence quantum yield Φ

Sign in / Sign up

Export Citation Format

Share Document