Design of high-resolution analysis technique for capillary electrophoresis microchip

In this study, we develop an electrophoresis microfluidic device featuring a conventional cross-form injection system and an expansion chamber located at the inlet of the separation channel. The combined injection system/expansion chamber arrangement is designed to deliver a high-quality sample band into the separation channel such that the detection performance of the device is enhanced. The current microfluidic device is investigated using a sample of Rhodamine B dye. Also, the effects of the expansion chamber on capillary electrophoresis (CE) separation are studied by considering the separation of Hae III-digested φx-174 DNA samples. The results indicate that an expansion chamber with an expansion ratio of 2.5 and an expansion length of 500 μm delivers a sample plug with the correct shape and orientation. The microfluidic device developed in this study has an exciting potential for use in high-performance, high-throughput chemical analysis applications and in many other applications throughout the field of micro-total-analysis systems.