THE DETERMINATION OF CATECHOLS IN THE PRESENCE OF ASCORBIC-ACID AND URIC-ACID BY FLOW-INJECTION ANALYSIS EMPLOYING A POTENTIOMETRIC DIBENZO-18-CROWN-6 ELECTRODE DETECTOR
A polished platinum disc was modified by electropolymerization of dibenzo-18-crown-6 (DB-18-C-6) onto the surface. This DB-18-C-6 electrode has been used as a detector for catechol and catecholamines in a potentiometric-flow injection mode. The potentiometric-flow injection response of the DB-18-C-6 modified electrode exhibited a linear response for catechol and catecholamine concentrations from 10(-2)-10(-6) M achieving detection limits as low as 0.5 x 10(-6) M. An interference study was carried out with ascorbic acid and uric acid which are serious interferents using amperometric detectors. No significant interference was observed for the presence of either of these two or mixture of these two common interferents until they were in greater than a 10-fold excess.