MONITORING OF HAPTEN-PROTEIN COUPLING REACTIONS BY CAPILLARY ZONE ELECTROPHORESIS - IMPROVEMENT OF ABSCISIC ACID-BOVINE SERUM-ALBUMIN COUPLING AND DETERMINATION OF MOLAR COUPLING RATIOS

The utility of capillary zone electrophoresis (CZE) was investigated f or the analysis of the coupling reaction of abscisic acid (ABA) - a pl ant hormone - on bovine serum albumin (BSA), a model hapten-protein co upling reaction. Through two different coupling reactions using the C1 carboxyl group or the C4' carbonyl group of ABA, we demonstrate a cor relation between the ABA/BSA molar coupling ratio and the modification of the electrophoretic mobility of BSA in CZE, in order to develop a rapid and efficient tool for coupling ratio determination. In addition , preliminary ABA activation steps were analysed by CZE to specify the stoechiometric and kinetic conditions of these reactions. These resul ts show that CZE is an effective and fast technique for the monitoring of hapten-protein coupling reactions.