Rough Glass Surface-Mediated Formation of Vesicles from Lauryl Sulfobetaine Micellar Solutions

Abstract

We report novel vesicles composed of the zwitterionic surfactant lauryl sulfobetaine (LSB), which is a simple single-tailed surfactant (STS). The novel vesicles spontaneously formed from LSB micellar solutions with the mediation of a rough glass surface (RGS) in the absence of any cosurfactants or additives. Importantly, the obtained STS vesicles displayed good stability upon long-term storage, exposure to high temperature, and freeze-thawing after the RGS was removed. The pH of the LSB solution (4.0-9.0) and the presence of NaCl (1.0 × 10(-5) and 1.0 × 10(-4) mol/L) in the LSB solution had no obvious influence on the formation and stability of the vesicles. The adsorption configuration of LSB on the RGS was investigated via water contact angle measurements and atomic force microscope observations. The results showed that LSB adsorption bilayers could form on the RGS, and the bilayer adsorption of LSB on the RGS and the roughness of the solid surface played a key role in the vesicle formation. A possible mechanism for the RGS-mediated formation of LSB vesicles is proposed: LSB micelles and molecules adsorb on the RGS to form curved bilayers, and the curved bilayers are then detached from the RGS and close to form vesicles. To the best of our knowledge, this is the first report of LSB alone forming vesicles. This finding extends our understanding of the nature of vesicle systems.

A Nonconventional Model of Protocell-like Vesicles: Anionic Clay Surface-Mediated Formation from a Single-Tailed Amphiphile

“…Commonly, simple STAs, such as sodium dodecyl sulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS), are considered to be unable to form vesicles in aqueous solution in the absence of cosurfactants or any other additives, even in chemical textbooks . More recently, we found an interesting phenomenon that rough glass surfaces can promote an STA spontaneously forming vesicles without any additives. , This inspired us to explore the probability of STA vesicle formation mediated by clay mineral surfaces, which played an active role in the abiotic origin of life …”

“…18 More recently, we found an interesting phenomenon that rough glass surfaces can promote an STA spontaneously forming vesicles without any additives. 19,20 This inspired us to explore the probability of STA vesicle formation mediated by clay mineral surfaces, which played an active role in the abiotic origin of life. 21 In this work, we chose two common anionic STAs, SDS and SDBS, as model constituents of early membranes rather than fatty acids, to establish a tentative model for protocell structures.…”

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.…”