Abstract: The invention provides fittings for the ends of electrochromatography cols. Each fitting includes an annular electrode surrounding one end of the passage electrical fields to be applied. The fitting also contains a passageway for eluant flowing into or out of the column, an annular chamber for the electrode and a membrane separating the passageway from the annular electrode chamber. The membrane prevents gases and electrolytic products from entering the column eluent going through the chromatographic column. The membrane also isolate the electrodes from the compounds such as proteins and macromolecules being separated. A buffer solution was pumped through the electrode chamber to remove the gases and electrode products. The buffer flow through the electrode chamber maintains a constant pH and conductivity so that the electrical field applied by each electrode is constant. The buffer flow also serves to remove the heat generated in the electrode chamber.