Separation of plant phenolic compounds by capillary zone electrophoresis

A capillary zone electrophoretic method with on-line UV detection was used for resolving fourteen phenolic species within 13 min by using a 100 cm x 75 mu m I.D. fused-silica tube with 0.01 M sodium berate buffer (pH 9.0) as electrolyte at 18 kV. The electrophoretic behaviour of phenolic species was investigated in order to optimize their separation as a function of the running buffer pH, concentration, solute injection method and time and applied voltage. Selectivity is strongly affected by the electrolyte concentration and pH. Quantitative aspects of capillary zone electrophoresis are also discussed.