Rough Glass Surface-Mediated Transition of Micelle-to-Vesicle in Sodium Dodecylbenzenesulfonate Solutions

Abstract

In this paper, we report a micelle-to-vesicle transition in aqueous solution of the anionic single-tailed surfactant (STS) sodium dodecylbenzenesulfonate (SDBS), with the mediation of a rough glass surface (RGS) in the absence of cosurfactants or additives. This transition produced a mixed solution of vesicles and micelles. Interestingly, the obtained SDBS vesicles in the solution displayed good stability during a long-term storage (at least 6 months at room temperature), exposure to high temperature (80 °C for 2 h), and freeze-thawing (-20 or -196 °C for 2 h to approximately 25 °C) after the RGS was removed. Our results confirmed that SDBS could adsorb on the RGS to form bilayers, in which the molecular packing parameter of SDBS was in the range of 1/2-1. The bilayer adsorption and the roughness of the solid surface played an important role in the vesicle formation. In addition, we propose a possible mechanism for the RGS-mediated transition of micelle-to-vesicle in SDBS solutions: SDBS micelles and molecules adsorb on the RGS to form curved bilayers; the curved bilayers detach from the RGS, and then close to form vesicles.

Surfactant and Cyclodextrin Induced Vesicle to Micelle to Vesicle Transformation in Aqueous Medium

“…Conversion of micelles to vesicles was previously done using bile salts or by adding organic compounds, heating, and on a rough glass surface. − However, these conversions appear more rigorous and complicated. Dai et al reported transformation of micelles to vesicles of catanionic surfactants using β-CD in aqueous medium .…”

“…In an early study, the micelle to vesicle transition of lipids and detergents was reported in the presence of a membrane protein where the high concentrations of the participating species induced crystallization . Micelle to vesicle transition could also be achieved using bile salt mixtures. , Heat and organic solvent additives can induce such transformation but deform the aggregate. − There are reports on ionic liquid and rough glass surface mediated transformation of micelles to vesicles as well. , Micelles to vesicles and vesicles to micelles conversion had been achieved by using catanionic surfactants where the mechanism was greatly dependent on the different headgroup charges. − …”

Vesicle formation of single-tailed amphiphilic alkyltrimethylammonium bromides in water induced by dehydration–rehydration

“…Furthermore, no obvious change in the appearance of vesiclesolutions was observed before and after heating at 80 1C for 2 h. These results indicate the remarkable stability of C n TAB vesicles, similar to our previous results on the vesicles of STAs. [25][26][27][28][29][30]33 3.4 Possible mechanism for DHRH-induced micelle-to-vesicle transition Based on the above results, it can be concluded that, using a DHRH process, the micelle-to-vesicle transition occurs for C n TABs in their single-component solutions (without any additives). For TTAB and CTAB, a complete transition from micelles…”

“…to vesicles can be achieved, forming pure vesicle systems, while for DTAB, only a partial transition occurs, forming a vesicle/ micelle coexisting system. In our previous reports, 25,26,28,30 it was demonstrated that RGSs can in situ mediate the micelle-to-vesicle transition for STAs in water, but smooth glass plates cannot. A possible mechanism for the RGS-mediated micelle-to-vesicle transition was proposed: 25 STA micelles and molecules adsorb on the RGSs to form curved bilayers, which are closed to form vesicles when detached from the RGSs.…”

“…However, we recently found that, under the mediation of solid surfaces (such as rough glass surfaces, RGSs), simple STAs can form vesicles from their respective micelle solutions without any additives. [25][26][27][28][29][30] The so-obtained STA vesicles coexist with micelles, and all such vesiclecontaining systems are transparent, [25][26][27][28][29][30] in contrast to the turbid appearance of conventional vesicle systems. 20,31,32 This is because the population and/or size of STA vesicles are small in the vesiclecontaining systems obtained by the solid surface in situ mediation.…”