Electrocatalytic oxidation of dopamine at the polyglycine chemically modified carbon fiber bundle electrode and its voltammetric resolution with uric acid

A polyglycine chemically modified electrode shows substantial catalytic ability towards dopamine (DA). The calibration graph obtained by linear sweep voltammetry for DA is linear in the range 2.0 x 10(-8) similar to 4.4 x 10(-6) mol/L and the detection limit is ca. 5.0 x 10(-9) mol/L. The catalytic ability towards DA results in the voltammetric resolution of DA and uric acid (UA) in the same solution, which is impossible at the unmodified electrode. Uric acid in less than 120-fold excess does not interfere with the determination of DA.