Electrocatalytic behavior of poly(2,6-pyridinedicarboxlic acid)/multi-walled carbon nanotube modified electrode

A poly (2, 6-pyridinedicarboxlic acid/multi-walled carbon nanotube composite( PPDA/MCNT) modified electrode was fabricated by electropolymerization of 2, 6-pyridinedicarboxlic acid on glassy carbon electrode with multi-wall carbon nanotube as dopant in neutral KCl solution. The modified electrode exhibited strong electrocatalytic behavior to the oxidation of dopamine (DA). Compared with carbon nanotube modified electrode, at PPDA/MCNT modified electrode, the oxidation peak potential of DA induced about 30 mV in phosphate buffer solution (pH 7.2). The oxidation peak current increased linearly with the concentration of DA in the range of 9.0 x 10(-8) - 8.0 x 10(-6) mol/L. The detection limit was 5.0 X 10(-8) mol/L. Furthermore, ascorbic acid and uric acid didn't affect the determination of DA.