Vesicles hydrotropes

Self-aggregating amphiphiles can broadly be divided into hydrotropes and surfactants. The main difference between hydrotropes and surfactants lies in the fact that hydrotropes are typically not sufficiently hydrophobic to cooperatively self-aggregate and form organized structures, whereas surfactants form distinct aggregates such as micelles and vesicles above their critical aggregation concentrations. 

Aqueous solutions of hydrotropes have proven to be powerful systems for preparing vesicles. In this case, the vesicle-forming compound has been mixed with water and the hydrotrope, and dilution with water resulting in the vesicles (33). Vesicles formed by the nonionic surfactant Laureth 4 (Brij 30) from an aqueous solution of sodium xylene sulfonate (SXS) were more stable and smaller than vesicles prepared from the suspension of the lamellar liquid crystal in water. 

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