Separation of Hydrogen-Bonding Donors in Capillary Electrophoresis Using Polyethers as Matrix

Addition of poly(ethylene glycol) (PEG) as a free matrix was found to be a novel separation parameter in capillary zone electrophoresis. In the separation of substituted and unsubstituted benzoic acids used as model analytes, attractive interaction with PEG was observed for the analytes with hydroxyl, amide, or amine groups. This interaction is attributable to hydrogen bond formation. The concentration and the polymer length of PEG can control the net strength of the interaction and then the observed separation. This capillary electrophoresis using the hydrogen-bonding mode was successfully applied to the separation of nucleotides