INFLUENCE OF BUFFER ELECTROLYTE PH ON THE MIGRATION BEHAVIOR OF PHENOLIC-COMPOUNDS IN CO-ELECTROOSMOTIC CAPILLARY ELECTROPHORESIS

The separation behavior of phenolic compounds with various substituent s was investigated with co-electroosmotic capillary electrophoresis (m igration of the analytes in the same direction as the electroosmotic f low). Co-electroosmotic flow conditions were set up when the electroos motic how direction was reversed by adding either a cationic surfactan t (cetyltrimethylammonium bromide) or a polycation (1,5-dimethyl-1,5-d iazaundecamethylene polymethobromide) to the buffer. An alkaline buffe r electrolyte was chosen to ensure complete dissociation of the phenol s (pH 10-12). It was shown that a separation of the chosen phenols was possible under co-electroosmotic conditions by optimizing the buffer pH.