Elena von Hoff¹, Silan Toy¹, Thomas Waitz¹, Ingo Mey^2,

Formation of supramolecular aggregates such as micelles and vesicles is governed by hydrophobic and hydrophilic interaction as well as the geometric shapes of the aggregating molecules. Here we present an experiment for upper secondary chemistry class to show how structural properties of molecules such as fatty acids govern the shapes of aggregates. For fatty acids, the pH value controls whether micelles or vesicles are formed. Using a size exclusion column and the possibility to encase fluorescing dye molecules in vesicles, the properties of micelles and vesicles are explored and compared to typical micelle building surfactants from dish detergent and the vesicle building lecithin.

self-aggregation, size exclusion column, surfactants, lipids, vesicles, micelles