Spectroscopic Studies on the Interaction of Dye and Surface Active Ionic Liquid

Abstract

The interaction of both cationic dye Safranine T (ST) and anionic dye Congo red (CR) with anionic and cationic surface active ionic liquid 1-butyl-3-methyl imidazolium octyl sulfate ([BMIM][OS]) and 1-decyl-3-methyl imidazolium chloride ([DMIM][Cl]) was investigated by absorbance and emission spectroscopy, time-resolved fluorescence study, and anisotropy methods at premicellar and postmicellar regions. The interaction of dye with both of the ionic liquids occurred electrostatically as well as hydrophobically. In the case of ST, initially absorbance decreases up to a certain concentration without any shift of λ max , and then it increases with red shift of λ max . Absorption spectra of CR gave red-shifted wavelength with addition of [BMIM][OS], but at a higher concentration of surface active ionic liquid (SAIL), no shifting was observed. Again, blue-shifted λ max was found in lower range of [DMIM][Cl]; but at higher concentration, it was further red-shifted. Emission intensity increases in both dye−SAIL systems; for ST in both SAIL media, blue-shifted spectra were observed, but there was no shift of emission maxima in case of CR in those media. Dye−IL binding ratio, binding sites, and binding constants were also calculated from fluorescence measurements. Anisotropy measurement showed that movement of dye in pre-and postmicellar regions was different in different SAIL systems. Time-resolved fluorescence lifetime confirmed microenvironment of dye−SAIL systems.

Exploring Physicochemical Interactions of Different Salts with Sodium N-Dodecanoyl Sarcosinate in Aqueous Solution

“…The G factor denotes the ratio of the sensitivities of the detection system between vertically and horizontally polarized light with fluorescence polarization anisotropy. 64,65…”

How Does Nanoconfinement within a Reverse Micelle Influence the Interaction of Phenazinium-Based Photosensitizers with DNA?

“…These results are found to be in good agreement with a large volume of literature reports. 23−26,28−30,51−57 The occurrence of drug:DNA interaction is indicated by the decrease in absorbance and significant red-shift of the absorption profile following interaction with DNA (Figure 1). 21,22 In this context, it is intriguing to note the varying extents of red-shift for the drugs at the respective saturation levels of interaction, Δλ ∼ 17 nm for PSF and Δλ ∼ 13 nm, for SO which readily suggests that the microenvironment in the vicinity of the drug molecules within the DNA scaffolds is not precisely the same (Figure 1).…”

“…The photophysical properties of the dyes PSF and SO in bulk homogeneous solvents have been extensively characterized in the literature. − ,− ,− In bulk aqueous medium PSF and SO show the lowest energy absorption band at ∼520 nm and a broad unstructured fluorescence band at ∼585 nm arising from charge transfer emission. The characteristic absorption and fluorescence profiles of the dyes are known to be sensitive to solvent polarity, the presence of external additives, and specific interactions with microheterogeneous assemblies. − ,− As a result, these dyes have been extensively used as extrinsic molecular probes for a variety of organized media and microheterogeneous assemblies. − ,− …”

“…The present study demonstrates the application of AOT reverse micelle as a condensing media to exploit the effect of nanoconfinement on the binding interaction of two phenazinium-based DNA intercalator drugs, namely, phenosafranin (PSF, 3,7-diamino-5-phenyl phenazinium chloride) and safranin-O (SO, 3,7-diamino-2,8-dimethyl-5-phenyl phenazinium chloride) (Scheme ). The photophysics of PSF and SO in various organized media is extensively studied. − The cationic drug molecules PSF and SO are reported to bind to DNA principally by an intercalative mode of binding. , The major focus of the present investigation aims at exploring how the binding interaction of the drugs (PSF and SO) is influenced within the nanoconfinements of reverse micelles. The variation of the binding constant values and polarity surrounding the drug microenvironment as a function of w 0 within the reverse micelle unveils the modification of the curvature of DNA within the nanocage of the reverse micelles with increasing hydration (that is, w 0 ) conveying the stabilization of the intercalative binding interaction of the drugs with DNA .…”

Studies of the Association of Dyes with Surfactants in Aqueous Solutions: Spectrophotometry and Computer Simulation

“…Such association is instrumentally fixed at relatively low molar concentrations of particles (from of 10 -7 to 10 -5 M) [1, 3-5, 10, 13, 14]. concentrations, CMC [16][17][18]), pharmaceutical chemistry and biochemistry (DNA modification, chemical analysis of drug components [19][20][21][22][23]).…”