Effect of solvents, solvent mixture and silver nanoparticles on photophysical properties of a ketocyanine dye

Abstract

The effect of solvents of varying polarity and hydrogen bonding ability, solvent mixture and silver nanoparticles on the photophysical properties of a ketocyanine dye, 2,5-di[(E)-1-(4-diethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DEAPMC), is investigated at room temperature. Solvent effect is analyzed using Lippert-Mataga bulk polarity function, Reichardt's microscopic solvent polarity parameter, and Kamlet's and Catalan's multiple linear regression approaches. The spectral properties better follow Reichardt's microscopic solvent polarity parameter than the Lippert-Mataga bulk polarity function. This indicates that both general and specific solute-solvent interactions are operative. Kamlet's and Catalan's multiple linear regression approaches indicate that polarizability/dipolarity solvent influences are greater than hydrogen bond donor and hydrogen bond acceptor solvent influences. The solvatochromic correlations are used to estimate excited state dipole moment using the experimentally determined ground state dipole moment. The excited state dipole moment of the dye is found to be larger than its corresponding ground state dipole moment and ground and excited state dipole moments are not parallel, but subtend an angle of 77°. The absorption and emission spectra are modulated in the presence silver nanoparticles. The fluorescence of 2,5-DEAPMC is quenched by silver nanoparticles. The possible fluorescence quenching mechanisms are discussed. Copyright © 2016 John Wiley & Sons, Ltd.

Investigation of the Fluorescence Turn-off Mechanism, Genome, Molecular Docking In Silico and In Vitro Studies of 2-Acetyl-3H-benzo[f]chromen-3-one

“…In the present case, the S-V plot in the steady state shows the concave upward curve in all ACN + DXN solvent mixtures . The presence of static quenching may be the reason for the presence of static quenching.…”

“…In the present case, the S-V plot in the steady state shows the concave upward curve in all ACN + DXN solvent mixtures. 36 The presence of static quenching may be the reason for the presence of static quenching. By comparing Figures 5 and 6 , we can say that both types of quenching, static and dynamic quenching, are present.…”

Effect of TiO2nanoparticles on some photophysical characteristics of ketocyanine dyes

“…Some ketocyanine dyes have been used as laser dyes or photosensitizers and have also found several industrial applications . Recently, we have investigated the influence of silver NPs on the absorption and fluorescence characteristics of two ketocyanine dyes 2,5‐di[(E)‐1‐(4‐dimethylaminophenyl) methylidine]‐1‐cyclopentanone (2,5‐DMAPMC) and 2,5‐di[(E)‐1‐(4‐diethylaminophenyl) methylidine]‐1‐cyclopentanone (2,5‐DEAPMC) . It has been found that spectral properties of these two dyes are sensitive to silver NPs.…”

“…[19][20][21] Recently, we have investigated the influence of silver NPs on the absorption and fluorescence characteristics of two ketocyanine dyes 2,5-di[(E)-1-(4-dimethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DMAPMC) and 2,5-di[(E)-1-(4diethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DEAPMC). [22,23] It has been found that spectral properties of these two dyes are sensitive to silver NPs. The sensitivity of these dyes to biological systems and the excellent capacity of TiO 2 NPs to carry chemical/biological species in therapeutic applications motivated us to carry out the present investigation.…”

“…[19][20][21] Recently, we have investigated the influence of silver NPs on the absorption and fluorescence charac- methylidine]-1-cyclopentanone (2,5-DEAPMC). [22,23] It has been found that spectral properties of these two dyes are sensitive to silver NPs. The sensitivity of these dyes to Abbreviations: FESEM, field effect scanning electron microscope; IRF, instrument response function; TCSPC, time-correlated single photon counting.…”