Abstract :
An improved and easy electrokinetic packing procedure is presented for the production of stable capillary columns suitable for capillary electrochromatography (CEC). In pseudo-electrokinetic packing a high electric field is used in conjunction with a hydrodynamic flow. The packing of silica-based reversed-phase columns can be achieved with basic, commercially available capillary electrophoresis (CE) equipment in approximately 15 min. The procedure is robust and a high success rate is achieved. No steps which might damage the stationary phase are involved and only a minimum amount of packing material is required. Columns packed according to the developed procedure are operated at high electric field strengths during the CEC separation, without the application of a stabilising pressure. Columns are stable for at least hundred runs and were tested using mixtures of polycyclic aromatic hydrocarbons and positively charged drugs. Separations were performed in a relatively high conducting ammonium acetate buffer, with efficiencies of up to 283 000 plates/m.
