Separation of 1,4-benzodiazepine Derivates by Micellar Electrokinetic Capillary Chromatography Using Cyclodextrines as Buffer Modifiers

The applicability of micellar electrokinetic capillary chromatography (MEKC) for the separation of benzodiazepine (BZD) derivates with different structural characteristics has been studied. Efforts were first focused on the optimization of the analytical conditions, on the effects of buffer concentration, surfactant concentration and buffer pH on the separation. To manipulate selectivity of the separation βcyclodextrin (CD) was added to the buffer solution, and urea was used to improve the solubility of the CD in water. The CD-modified MEKC separation of the eight BZDs was achieved within 15 minutes using 25 mmol dm natrium tetraborate-50 mmol dm sodium dodecyl sulphate-15 mmol dm β-CD-2 mol dm urea (pH 9.3) as the running buffer. The proposed separation method was evaluated on the basis of precision, linearity and limit of detection. (doi: 10.5562/cca1763)