Amperometric Quantification of Dopamine Using Different Carbon Electrodes Modified with a Melanin-Type Polymer.

M. D. RUBIANES, G. A. RIVAS

ANALYTICAL LETTERS

Marcel Dekker

Lugar: Cork, Irelend; Año: 2003 vol. 36 p. 329 - 329

0003-2719

he analitycal performance of different carbon materials (glassy carbon, glassy carbon paste, graphite, graphite paste, carbon fiber and screen printed electrodes) modified with melanic polymer is evaluated in connection with the quantification of dopamine. The electropolymerization was performed from 3.0 x 10-3 M L-dopa solution (in a 0.050 M phosphate buffer pH 7.40) by applying 1.00 V for 60 min. The response of the polymer-modified carbon electrodes demonstrated to be very dependent on the nature of the carbon material, glassy carbon being the best. By using 1.0 x 10-3 M AA in the measurement solution, detection limits of 5.0 and 10.0 nM were obtained with a melanin-type polymer modified glassy carbon and carbon fiber electrodes, respectively. The interference of 5.0 x 10-4 M ascorbic acid and 5.0 x 10-5 M dopac at the melanin-type polymermodified glassy carbon electrode, was 7.0 and 3.0 %, respectively. A comparison between a glassy carbon electrode modified with a comm