[Separation of 1,4-benzodiazepine derivates by micellar elektrokinetic capillary chromatography].

Our aim was to develop a capillary electrophoresis method for the separation of 1,4-benzodiazepine derivates. Benzodiazepines are hydrophobic substances, neutral from electrophoretic point of view, consequently the best method for their separation proved to be micellar elektrokinetic capillary chromatography (MECC). A fast and reliable method has been developed, for the 8 of the most frequently used benzodiazepine derivates, using a separation buffer composed of sodium tetraborate 25 mM (pH 9.3), SDS (50 mM) and methanol (at least 12%) as an organic modifier. Beside the separation we also studied the analytical condition for the separation (i.e. the effects of buffer concentration, modifier concentration and buffer pH on the separation).