Capillary electrophoresis microchip detecting system based on embedded optical fiber

Microchip capillary electrophoresis(CE) has been recognized as a powerful tool for biochemical analyses due to its smaller size, faster separation and lower sample requirement. According to the principle of laser-induced fluorescence, the detecting system of CE microchip embedded optical fiber is discussed in this paper as well as its small volume and simple detection optical circuit. The system was composed with semiconductor laser (532nm), high voltage control system, photon counter, PC and CE chip embedded optical fibers. With the constructed detection system, different samples and different concentrations were detected, including Rhodamine B, Rhodamine 6G, and mingling solution of Rhodamine B and Rhodamine 6G. The lowest detected concentration is 1 x 10(-6) mol/L for Rhodamine B, and 1 x 10(-5) mol/L for Rhodamine 6G, respectively. The separation of the mingling solution of Rhodamine B and Rhodamine 6G was completed, whose concentration were both about 1 x 10(-4) mol/L. The results show that the constructed detection system possesses some advantages, such as compact structure, higher sensitivity and repetition, which are beneficial to the development of microminiaturization and integration of micro CE chip.