CAPILLARY ELECTROPHORESIS OF PEPTIDES USING RECTANGULAR AND CYLINDRICAL GEOMETRIES - A COMPARATIVE-STUDY

A study on the use of rectangular columns in capillary zone electrophoresis (CZE) is presented. The equations controlling the hydrodynamic flow and the plate height in rectangular capillaries are deduced. Several experiments were carried out in order to test the validity of these equations. Also, the possibilities of these columns in terms of thermal dissipation, efficiency, analysis speed and sample capacity were studied and compared with those for cylindrical tubing. The results from both rectangular and cylindrical columns are compared to each other, employing the parameters mentioned above, and also with those predicted by theory. The advantages, i.e. better heat dissipation, higher speed and larger sample capacity, and drawbacks, i.e. high fragility and incompatibility with some capillary electrophoresis instruments, of employing rectangular geometries in CZE are discussed.