What is CE?
Capillary electrophoresis(CE) and chromatography are techniques for chemical analysis. It is generating tremendous interests in industrial labs due to their high sensitivity, high separation efficiency and rapid rate of analysis in many industrial applications. CE is able to accurately determine chemical compositions and detecting trace impurities.
Even small deviations from process specification or minute amounts of contaminants can seriously affect product quality and yield in high technology manufacturing industries, such as semiconductor manufacturing and pharmaceutical production. In other words, CE enables analysis to be accomplished fast, easily and accurately!
Background of Capillary Electrophoresis (CE)
Capillary electrophoresis (CE) is a modern variant of electrophoresis in instrumentation. Electrophoresis is a separation technique based on the differential migration of electrically charged molecules or particles in a conductive liquid-based medium under the influence of an electric field. Distinctive feature of capillary electrophoresis is the use of small capillaries which have large ratios of area-to-volume. Efficient heat dissipation allows the use of high voltage for the separation. All the capillary electrophoresis modes above can share the same instrumental setup, such as a portable CE system (Model CE-P1) or a conventional CE systems (CE-L1 with an detector).
Another format of capillary electrophoresis is performed on a microchip, namely microchip capillary electrophoresis. In addition, a lab-on-a-chip system can be used for accomplishing more complicate analytical tasks requiring highly integrated instrumentation.
Capillary electrophoresis, as an modern analytical technique, has been applied for inorganic ion analysis, environmental monitoring, water analysis, clinical analysis, food analysis, drug screening and biochemical analysis.
Why use CE?
- High Efficiency
This is due to the flat flow profile of electrically driven flows. The flat flow profile gives rise to sharp peaks which can be resolved more readily.
Many different separation mechanisms can be introduced by simply changing the buffer solution used. With CE, you can do so much!
A tiny drop(less than a microliter) of the buffer solution, a fraction of a drop (several nanoliter) of the sample solution and a capillary which is cheaper than any HPLC and GC columns, are all the things that you need for a typical CE analysis. You will save on solvent usage and the costs of columns!
What is Potential Gradient Detection?
Potential gradient detection (PGD) is based on the changes in the electric field strength between zone boundaries during electrophoresis. The electric field strength is inversely proportional to the ionic mobility. Therefore, PGD originates from the differences in mobility between migrating zones, and is applicable to all charge-carrying compounds. It is similar to conductivity detection, but it does not need alternating or direct current. To measure the potential changes, two sensing electrodes are put longitudinally along the separation capillary. When sample components pass through the region between the two sensing electrodes, the potential from the two sensing electrodes will change and the analytes can be detected.
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