Design and application of new stationary phases for (pressurized) capillary electrochromatography (China) (BWS07/03)

In last years, some attention was paid to capillary electrochromatography (CEC) due to the need for rapid method development in life sciences, environmental sciences and pharmaceutical analysis. CEC can be viewed as a hybrid between capillary electrophoresis (CE) and microcolumn liquid chromatography (micro-LC): its separation mechanism is mainly chromatographic for neutral species, while the mobile phase transport is mediated through the electroosmotic action. For charged species, the separation mechanism is based on both chromatographic partition and electrophoretic mobility. CEC is carried out in fused-silica capillaries of 50 to 320 µm I.D. packed with small (typically 3-5 µm) silica based particles. The mobile phase moves through the capillary column by the electroosmotic flow (EOF) generated in the column under an applied electric field across the length of the capillary. In CEC, the stationary phase is the heart of the technique and a variety of bonded phases have been used. These include modified silica gel, ion-exchange materials, mixed-mode phases, organic polymer monoliths and silica sol-gel monoliths. The stationary phases now used in CEC separation process are about 68% based on C18-modified silica gel and are primarily designed for Liquid Chromatography (LC). Compared with the role of the stationary phases used in LC we know that they play a dual role in the CEC separation process: provide the interaction sites for the solutes and generate the EOF to push the mobile phase through the chromatographic bed. So, in order to get even higher separation efficiencies in CEC or to fit for the even more challenging bio-compounds separation using the CEC technique there is a need to develop new types of stationary phases specifically designed for CEC. The development of some new stationary phases and the optimisation of some applications are the goals of the project.

Keywords:New stationary phases, Stationary phase development, (Pressurised) capillary electrochromatography, Application development

Disciplines:(Bio)chemical engineering, Chemical sciences, Materials engineering, Pharmaceutical sciences