Separation and determination of aromatic acids in natural water with preconcentration by capillary zone electrophoresis

A method was developed for the determination of aromatic acids by capillary zone electrophoresis (CZE) in combination with UV detection using hydrodynamic sample injection. The electrophoretic behavior of aromatic acids was investigated to optimize their separation as a function of buffer pH, buffer concentration, applied voltage and sample injection time. A good linearity was observed for all analytes over a wide concentration range (5-100 mu M) The relative standard deviation was less than 7% for all the aromatic acids tested. The method was applied to the analysis of aromatic acids in natural waters. The aromatic acids in the natural water sample were preconcentrated by means of solid-phase extraction (SPE). The recovery using the CZE in combination with the SPE procedure for the determination of aromatic acids was also investigated. (C) 1998 Elsevier Science B.V. All rights reserved.