Techniques - Capillary Electrophoresis (CE)

In High Performance Liquid Chromatography (HPLC), Gas Chromatography (GC) and Thin Layer Chromatography (TLC) the separating force is the difference in affinity of the sample components to a stationary phase, and or difference in boiling point. With both techniques the most important factor is the polarity of a sample component. In Capillary Electrophoresis the separating force is the difference in charge to size ratio. Not a flow through the column, but the electric field will do the separation.

In Capillary Electrophoresis a capillary is filled with a conductive fluid at a certain pH value. This is the buffer solution in which the sample will be separated. A sample is introduced in the capillary, either by pressure injection or by electrokinetic injection. A high voltage is generated over the capillary and due to this electric field (up to more then 300 V/cm) the sample components move (migrate) through the capillary at different speeds. Positive components migrate to the negative electrode; negative components migrate to the positive electrode. When you look at the capillary at a certain place with a detector you will first see the fast components pass, and later on the slower components.

Applications of Prince Capillary Electrophoresis include:

• Beverages
• Biochemical analysis
• Chiral separations
• Clinical analysis
• DNA/RNA
• Drug screening
• Environment monitoring
• Food analysis
• Inorganic ion monitoring
• Pharmaceuticals
• Proteins
• (Waste) water analysis