An integrated design for electrically driven separations is presented. The injector, column and detector are all located within the same cartridge, allowing for integral thermostating and short column lengths. Results on the performance of the proposed fluorescence detector are reported. Molar amounts as low as 2·10-19 mol of fluorescein (100-pl detector cell volume) can be detected. Short column lengths permit very fast separations, as is demonstrated by the separation of four laser dyes within 35 s.