Liposomes are spherical bilayer aggregates formed in aqueous solution by phospholipids; they are characterized by an interfacial region formed by the head groups of the constituent molecules, a fluid organic region formed by the fatty tails of the lipids, another interfacial region of head groups, and an inner aqueous pool. Due to their structural similarities to biological membranes, liposomes are often used to model cells.

In the first part of this presentation, the usefulness of Liposome Electrokinetic Chromatography (LEKC) for rapid and high throughput screening of drug – membrane interactions as well as for modeling of cell membrane permeability and oral absorption of a series of drugs will be demonstrated. In a related project, the colorimetric shifts in vesicles were utilized for studying membrane partitioning of solutes that lack a UV chromophore.

Finally, the use of CE-LIF as a sensitive and efficient method to study encapsulation efficiency and membrane permeability behaviors of large unilamellar vesicles (LUV) will be discussed.