4.4.3 Capillary Electro-Chromatography (CEC)

Capillary electro-chromatography is miniaturized liquid chromatography. An applied electric field pumps liquid through a packed capillary column. The silica capillaries are packed with silica-based reversed-phase particles of 1-5µm diameter. The migration times of different solutes vary as a function of their partitioning between the mobile and stationary phases. If the packed phase is charged, there is also an electrophoretic component to the partitioning. On average, there are 100,000 theoretical plates per peak in a CEC system.

As the only difference in a CEC setup is the capillary tubing used, CZE systems can be easily set up for CEC analysis.

Figure 4.9. CEC Setup