Spectroscopic and conductometric studies on the interactions of thionine with anionic and nonionic surfactants

Abstract

In this study, the interaction of thionine, a cationic dye, with anionic [sodium dodecyl sulphate (SDS), lithium dodecyl sulphate (LiDS), and sodium dodecylbenzene sulphonate (SDBS)], nonionic (Tween 20 and Triton X‐100), and binary mixtures of anionic and nonionic surfactants was studied by conductometric and spectrophotometric measurements. The degree of ionisation, the counterion binding parameters, and the equilibrium constants in the premicellar region were obtained from conductivity data. Binding constants of thionine to anionic, nonionic, and mixtures of anionic and nonionic micelles were determined by spectrophotometric measurements. The binding tendency of thionine to anionic micelles followed the order SDBS > SDS > LiDS. The presence of nonionic surfactants increased significantly the binding affinity of thionine to anionic micelles, and the highest binding constant was calculated in the presence of Tween 20. The results obtained from conductometric studies correlated with those obtained from spectroscopic studies. Data concerning dye–surfactant interaction are important for a fundamental understanding of the performance of single and mixed surfactants and for their industrial application.

Mixed Micellar Solubilization of Naphthol Green B Followed by Its Removal from Synthetic Effluent by Micellar-Enhanced Ultrafiltration under Optimized Conditions

“…These complexes are different from their parent moieties and display an altered absorption spectrum. The micro-environment of dye molecules also affects their absorption spectrum [ 24 , 25 ]. Scheme 1 displays the interaction of NGB with CTAB and CPC.…”

“…For the solubilization process, mixed micellization is more efficient as compared to a single surfactant system. The literature reported single micellar systems as ineffective for homogeneous dispersion of hydrophobic moieties [ 24 ]. Mixed micellization has been performed by both of the cationic surfactants individually by taking five different concentrations of, i.e., 0.09 mM, 0.11 mM, 0.13 mM, 0.15 mM, and 0.17 mM, to assess the potential of non-ionic surfactants for dye intercalation enhancement in cationic/nonionic surfactant systems.…”

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

“…Recently, the development of spectralluminescent methods initiated the systematic studies of the association phenomenon involving dyes in solutions [1][2][3][4][5][6][7][8][9][10][11][12][13]. 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].…”