Abstract: Embodiments of a device and method are described which provide for control over the distortion of a sample zone upon exiting an electrophoresis separation channel. According to the teachings herein (i) the downstream regions of the channels, near the outlet ends, and/or (ii) the detection chamber, is/are configured so that distortion of one or more sample zones passing from the channels into and across the detection chamber can be controlled (e.g., reduced) in a fashion affording enhanced detectability. In certain embodiments, the lumens along the end regions of the separation channels progressively expand.