Electrochemical behavior of dopamine at the poly (isonicotinic acid) modified glassy carbon electrode / 药学学报

ABSTRACT

<p><b>AIM</b>To study the determination of dopamine (DA) in the presence of ascorbic acid (AA) using poly (isonicotinic acid) film modified electrode.</p><p><b>METHODS</b>The cyclic voltammetry and differential pulse voltammetry were used to study the electrochemical behavior of DA at the poly (isonicotinic acid) film modified electrode.</p><p><b>RESULTS</b>The poly (isonicotinic acid) film modified electrode showed an electrocatalytic effect on DA, and shifted the oxidation of AA to negative potential. The difference between the oxidation potentials of DA and AA was 204 mV, thus, AA did not interfere with the determination of DA. The linear range between the anodic currents and DA concentration was: 1.0 x 10(-7)-2.0 x 10(-5) and 2.0 x 10(-5)-1.0 x 10(-4) mol.L-1. The detection limit was 8.0 x 10(-9) mol.L-1.</p><p><b>CONCLUSION</b>The useful life period of the modified electrode is three weeks at least. The modified electrode can be used to the determination of DA in the sample.</p>