Comparison of three different microemulsion systems as the run buffer for the capillary electrophoretic separation of ketone test solutes

Capillary electrophoretic behavior of ketones and β-diketones was examined using anionic, nonionic and cationic oil in water (o/w) microemulsions as separation media, containing naphthalene as a fluorophore for means of indirect fluorescence detection. The migration behavior was greatly dependent on the charge type of microemulsions as well as on the composition and pH. Among the systems examined, sodium dodecyl sulfate (SDS) microemulsions were the most advantageous because of the wider separation window, the higher dissolution capacity and the rapid distribution rate. Capacity factors of the solutes in the electrophoresis employing SDS microemulsions were correlated to the distribution and interfacial adsorption parameters determined in bulk two-phase systems.