The formation and stability of sodium dodecylsulfate vesicles mediated by rough glass surface

Abstract

Under the mediation of a rough glass surface (RGS), formation of vesicles was realized from a micellar solution of only a simple anionic single-tailed surfactant (STS), sodium dodecylsulfate (SDS), to form a mixed solution of micelles and vesicles. Interestingly, the SDS vesicles formed in the solution displayed good stability upon long-term storage, exposure to high temperature, freeze–thawing, and high salinity after the RGS removal. Adsorption and water contact angle measurements demonstrated that SDS could adsorb on the RGS to form bilayers in which the molecular packing parameter of SDS was in the range of 1/2–1. The bilayer adsorption and the roughness of the solid surface played an important role in vesicle formation. AFM observations suggested that the alkyl tails of SDS in the vesicular bilayer membranes were partially interdigitated, and molecular dynamics simulations revealed that the partially interdigitated bilayer structure is crucial for the formation and stability of the SDS vesicles. This work contributes to the understanding of the nature of vesicle systems.