Effect of ionic strength on perfusive flow in capillary electrochromatography columns packed with wide-pore stationary phases

The use of wide-pore stationary phases in capillary electrochromatography has shown exceptional increases in separation efficiency in conjunction with high electroosmotic flow. These effects are due to the perfusive flow mechanism which is primarily controlled by the ionic strength of the mobile phase. Good correlation between calculated values of electrochemical double-layer thickness and efficiency data have also been obtained. Reduced plate height values of <0.5 have been observed with pore sizes of 4000 A. In addition, electroosmotic flow mobility twice that of 3 μm Spherisorb ODS-1 has been obtained.