Rapid determination of liposome–water partition coefficients (Klw) using liposome electrokinetic chromatography (LEKC)

Liposome Electrokinetic Chromatography (LEKC) provides a simple and facile approach for determining liposome–water partition coefficients, Klw. LEKC is a Capillary Electrophoresis (CE) technique where liposomes are incorporated into a buffer solution and act as a pseudostationary phase providing sites of interaction for solutes. The retention factors of solutes in LEKC are directly proportional to Klw. This article describes how LEKC can be used to determine Klw for both neutral and charged solutes. The Klw values for a group of neutral aromatic compounds, β‐blockers, and other drugs are reported. In addition, the usefulness of two quantitative structure partition relationships (QSPR) for estimation of Klw is demonstrated. One is the logarithmic linear relationship between liposome water and octanol–water partition coefficients (Pow). The other is the Linear Solvation Energy Relationship (LSER). The calculated Klw values from the two QSPR agree nicely with the observed values and with one another. © 2002 Wiley‐Liss Inc. and the American Pharmaceutical Association J Pharm Sci 91:1601–1612, 2002