Time-Resolved Fluorescence Studies of Hematoporphyrin in Different Solvent Systems

Time-resolved fluorescence studies of hematoporphyrin in aqueous solution and in different organic solvents are presented. The| observation of two exponential components in the fluorescence decay in aqueous solution reveals the presence of a monomeric and aggregated (probably dimeric) form of the molecule, as confirmed by absorption and fluorescence measurements. The slow component (~ 15 ns in aqueous solution) and the fast one (~ 3.8 ns in aqueous solution) are attributed to monomers and dimers, respectively. Higher aggregated species of hematoporphyrin are also present, which are essentially devoid of fluorescence properties.

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Exploring Aqueous Solution Dynamics of an Amphiphilic Diblock Copolymer: Dielectric Relaxation and Time-Resolved Fluorescence Measurements

The Journal of Physical Chemistry B ◽

10.1021/acs.jpcb.9b00889 ◽

2019 ◽

Vol 123 (27) ◽

pp. 5892-5901 ◽

Cited By ~ 4

Author(s):

Ejaj Tarif ◽

Biswajit Saha ◽

Kallol Mukherjee ◽

Priyadarsi De ◽

Ranjit Biswas

Keyword(s):

Aqueous Solution ◽

Dielectric Relaxation ◽

Diblock Copolymer ◽

Time Resolved Fluorescence ◽

Time Resolved ◽

Amphiphilic Diblock Copolymer ◽

Fluorescence Measurements ◽

Solution Dynamics

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Time-resolved fluorescence studies of flavodoxin. Fluorescence decay and fluorescence anisotropy decay of tryptophan in Desulfovibrio flavodoxins

European Biophysics Journal ◽

10.1007/bf00185419 ◽

1990 ◽

Vol 18 (1) ◽

pp. 43-55 ◽

Cited By ~ 15

Author(s):

H. R. M. Leenders ◽

J. Vervoort ◽

A. van Hoek ◽

A. J. W. G. Visser

Keyword(s):

Fluorescence Anisotropy ◽

Fluorescence Decay ◽

Time Resolved Fluorescence ◽

Fluorescence Anisotropy Decay ◽

Time Resolved ◽

Fluorescence Studies ◽

Anisotropy Decay

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Concentration and Temperature Dependence of Laurdan Fluorescence in Glycerol

Zeitschrift für Naturforschung A ◽

10.1515/zna-2003-9-1018 ◽

2003 ◽

Vol 58 (9-10) ◽

pp. 581-588 ◽

Cited By ~ 6

Author(s):

K. A. Kozyra ◽

J. R. Heldt ◽

J. Heldt ◽

M. Engelkec ◽

H. A. Diehl

Keyword(s):

Steady State ◽

Time Distribution ◽

Emission Spectra ◽

Fluorescence Decay ◽

Time Resolved Fluorescence ◽

Time Resolved ◽

Fluorescence Measurements ◽

Fluorescence Decay Time ◽

Laurdan Fluorescence ◽

Vibrational Equilibrium

Steady-state and time-resolved fluorescence measurements have been performed on Laurdan, dissolved in viscous glycerol, as functions of temperature and concentration. The results indicate spectral heterogeneity of the Laurdan solution. The fluorescence decay time distribution is attributed to radiative deexcitation of spatial conformational forms of locally excited (LE) and charge transfer (CT) states, the S1(CT)EQ state being in thermodynamic and vibrational equilibrium. The lifetimes and contributions of the different fluorescence modes depend on concentration and temperature. The excitation and emission spectra show discontinuous changes with increase of the Laurdan concentration.We suppose that the observed changes are caused by the formation of Laurdan micelle aggregates.

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Ground and excited-state interactions of coumarin and nucleotide base

Canadian Journal of Chemistry ◽

10.1139/v88-087 ◽

1988 ◽

Vol 66 (3) ◽

pp. 513-516 ◽

Cited By ~ 17

Author(s):

Grażyna Wenska ◽

Stefan Paszyc

Keyword(s):

Organic Solvents ◽

Relative Proportion ◽

Stacking Interactions ◽

Dynamic Quenching ◽

Time Resolved Fluorescence ◽

Quenching Mechanism ◽

Time Resolved ◽

Nucleotide Base ◽

Fluorescence Measurements ◽

Total Fluorescence

Steady-state and time-resolved fluorescence measurements for a series of bichromophoric compounds containing 7-methoxy-coumarin and nucleotide base residues have been performed in water and in organic solvents. The data from these studies have been used to calculate the relative proportion of folded and extended conformations of bichromophores. Ground-state stacking interactions of coumarin and nucleotide base have been found to be limited to aqueous solution. The contribution of the dynamic quenching mechanism to the total fluorescence quenching in water has been estimated. The absence of dynamic quenching in organic solvents is.explained on the basis of the very short lifetime of the fluorophore in methanol.

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