Theoretical studies of the preparation of packed capillary columns for chromatography

The theoretical aspects of the preparation of packed capillary columns for chromatography have been studied. The variation of the mean bulk density of the columns prepared with carbon dioxide fluids in different physical states and under different supercritical fluid conditions has been investigated. A new concept of the packing formation during the preparation of packed capillary columns with supercritical CO2 as packing fluid is described. A mathematical model for column preparation is derived that indicates the importance of the sonication effect in packing process. This studies indicate that the column performances (density and efficiency) can be controlled by varying the packing conditions. The wall effect in packed capillary columns (the effect of the packing densities on the column efficiencies) and the explanation for the production of very long columns are also discussed.