SENSITIVE AND SELECTIVE METHOD FOR THE SEPARATION OF ORGANIC-ACIDS BY CAPILLARY ZONE ELECTROPHORESIS

A simple and rapid method was developed for the separation and determination of a large number of organic acids by using capillary zone electrophoresis, with hydrostatic injection for 30 s and UV detection at 254 nm. Electropherograms were obtained with 4-hydroxybenzoate buffer (5 mM) adjusted to pH 4.75 at 25 degrees C. The electroosmotic flow modifier (commercial solution) was added to the buffer at a concentration of 25 ml l(-1). Co-migration problems could be solved by modifying the pH of the electrophoresis buffer or by addition of Ca2+ to the buffer.