Microfluidic chip-based capillary electrophoresis (CE), as a main area of development of microfluidic chips, has undergone rapid development in recent years.Chip-based CE systems provide outstanding advantages including extremely fast separations, low sample/reagent consumption, and potential for achieving high-throughput separations in multi-channel array.However, hitherto, in most chip-based CE systems, a discrete and manual approach to sample changing using on-chip reservoirs or split-flow interface has still been adopted, which lowers the overall throughput and counteracts their advantage of achieving fast separations.