Microchip electrophoresis was used to resolve a binary mixture in 0.8 ms using a separation field strength of 53 kV cm(-1) and a separation length of 200 mu m. The microchip design permitted an electric field strength of 6.1 V cm(-1) in the separation channel per volt applied to the microchip. Concurrently, the spatial extent of the injection plug and the detector observation region were minimized to increase separation efficiency.