Spectroscopic Study of the Ternary Complex of Beta-Cyclodextrin, Pyrene, and Triton X-100

Abstract

The increased fluorescence intensity of pyrene due to indirect excitation by the nonionic surfactant Triton X-100 is discussed. Sensitization is quantitatively shown to occur in mixed solutions of pyrene, Triton X-100, and β-cyclodextrin (β-CD). A ternary complex is formed below the critical micelle concentration (CMC). Above the CMC, pyrene is displaced from the β-CD cavity. This is accompanied by a subsequent incorporation of pyrene into the interior of the micelle. Evidence is given that ternary complexation occurs among pyrene, CD, and TX-100.

Room-Temperature Phosphorescence of 1-Bromonaphthalene upon Formation of Beta-Cyclodextrin Ternary Complexes with Alcohols and Surfactants: Optimization of Analytical Figures of Merit by Rigorous Equilibrium Studies

“…The CMC of TX was determined to be in the range 1.4 -4.5 3 10 2 4 M, depending on the speci c technique and temperature employed. [36][37][38] However, in the presence of excess b-CD the surfactant is included in its cavity, and the micelles are form ed at higher analytical concentrations of TX. 27 The portion of the RTP titration pro le where m icelles are absent could be explained by the formation of a 1:1:1 BrNp-CD-TX complex.…”

“…4B is subject to considerable uncertainty. [36][37][38] Therefore, an experiment analogous to method 1 was devised, keeping the CD concen- Measurem ent of the RTP signal allowed the optimal conditions of m aximum emission to be reached, which turned out to be those theoretically expected (C CD 5 0.01 M, C TX 5 5 3 10 2 3 M). These latter conditions were then selected for the construction of the calibration curve.…”

“…Since the CM C of SDS in water is 8.3 3 10 2 3 M, 40 and the incorporation of the surfactant inside the CD cavity leaves a smaller free concentrations, one would expect micellation to occur at higher analytical concentrations of SDS. 37 However, Xie et al 25 determined that in the SDSb-CD system the aggregation of the surfactant is induced by b-CD below its CMC. This critical aggregate concentration was determined to be 8 3 10 2 4 M. 25 According to our results, the aggregation would occur at a higher value (; 6 3 10 2 3 M).…”

Enantiomeric separations using polymeric L‐glutamate surfactant derivatives: Effect of increasing steric factors

“…Fluorescent probes or fluorophores have been used extensively to determine the polarity of micelles and polymeric surfactants in aqueous environments using steadystate fluorescence [27][28][29][30][31]. The emission spectra of fluorophores such as pyrene are known to be sensitive to solvent polarity.…”

Interaction and charge transfer between isolated thylakoids and multi-walled carbon nanotubes

“…7A and B), which agrees with previous reports. 42,43 To examine the charge transfer between thylakoids and TX-100, the thylakoids are incubated in the absence and presence of TX-100. In the absence of TX-100, thylakoids exhibit fluorescence emission from B660 to 690 nm with the highest fluorescence detected at B680 nm (data not shown).…”