Characterization of micelles by capillary electrophoresis

A practical approach for the characterization of pure micelles, and binary or ternary mixed micelles by capillary electrophoretic methods is presented. Interest is focused on the determination of mobility and composition of the micelles. The investigations are performed with bile salts, phosphatidylcholines and fatty acids. Pure bile salt micelles are characterized with the help of marking and displacement methods. Binary bile salt/phospholipid and ternary bile salt/phospholipid/fatty acid micelles are analyzed using capillary electrophoresis (CE) techniques with standard and improved UV detection, laser-induced fluorescence and electrospray ionization-mass spectrometry (ESI-MS). For both the binary and the ternary systems, only one stable mixed micellar phase is found with a high negative mobility.