High-Performance Microchip Electrophoresis by Using On-Line Sample Preconcentration and Partial Filling Techniques

Microchip electrophoresis (MCE), which is based on capillary electrophoresis, is performed in a microchannel fabricated on a planner plate. MCE proxides rapid and high-resolution analyses for a small amount of analytes. In MCE, however, a low concentration sensitivity is often problematic, which interferes further progress of MCE. To improve the sensitivity, several on-line sample preconcentration techniques have been applied to MCE. However, they sometimes cause a decrease in the separation efficiency and/or an increase in the analysis time. To overcome these problems, we applied a partial filling technique to MCE, and developed an on-line sample preconcentration technique, named "transient-trapping". These novel approaches should provide a high-performance MCE analysis.