OPTIMIZED MICELLAR ELECTROKINETIC CHROMATOGRAPHIC-SEPARATION OF BENZODIAZEPINES

Although capillary zone electrophoresis is an inadequate method for th e separation of electrically neutral benzodiazepines, their separation can be achieved by micellar electrokinetic chromatography (MEKC). The cyclodextrin (CD)-modified MEKC separation of nine benzodiazepines wa s obtained within 24 min at 15 kV on a 470 mm x 75 mu m I.D. silica ca pillary at 30 degrees C using 50 mM borate-50 mM sodium dodecyl sulfat e-20 mM gamma-CD2 M urea (pH 9.2) containing 1% of tetrahydrofuran as the running buffer. The effects of gamma-CD concentration, urea concen tration, percentage of organic solvent and applied voltage on the reso lution were studied.