Application of capillary electrophoresis for characterizing interactions between drugs and bile salts .1.

Capillary electrophoresis offers a new way of characterizing interactions between different bile salts and drugs. The observed interactions were characterized with modified model functions known from affinity capillary electrophoresis (ACE) and micellar electrokinetic capillary electrophoresis (MECC). The methodical background of both methods is the change of the ionic mobility of the drug caused by partition between different phases and aggregation with the bile salt molecules, respectively. This phenomenon is described by two different physicochemical models. A parameter estimation was carried out in order to obtain the partition coefficients K-P as well as constants for the aggregate formation K-A. Furthermore, an expression about the specific molar volume of the micelles and stoichiometric coefficients can be given.