An Electrochemical Sensor Based on Electroreduction of Graphene Oxide on a Glassy Carbon Electrode Using Multiple Pulse Amperometry for Simultaneous Determination of L-Dopa and Benserazide

In this work, we described the development an electrochemical sensor based on electroreduction of graphene oxide (rGO) on a glassy carbon electrode (GCE) for simultaneous determination of l-Dopa and benserazide. For the elaboration of the GCE/rGO, the developed methodology was based on the electrochemical technique: multiple pulse amperometry (MPA). The MPA was more stable and efficient for the formation of rGO film, under optimum conditions (pH 6.00; concentration of rGO 2.00 mg mL; time 450 s; potentials −0.60, −0.70, −0.80, −0.90, −0.95, −1.00, −1.10, −1.20, and – 1.30 V). After the film was formed, the cyclic voltammetry was used to detect LD and BZ in real samples and optimized conditions 0.05 mol L PBS (pH 5.50). The linear range for the LD is 25–425 μmol L and the BZ of 5–80 μmol L. The limit of detection calculated was 17.10 (LD) and 2.99 (BZ) μmol L.