Optimization of fast CE analyses of ecstasy derivatives by use of experimental designs

The separation by capillary electrophoresis of five ecstasy derivatives has been evaluated by means of experimental designs. A full-factorial design a nd a central composite design were employed to optimize the experimental co nditions for a fast separation. With a conventional capillary (62.5 cm leng th) analytes were separated in less than 8 min. When the capillary:length w as reduced the analysis time decreased substantially. Comparisons were made between different procedures (e.g. working at a constant field or at const ant voltage) and finally, a fast separation of five Ecstasy derivatives was achieved in 1 min.