ELECTROCHEMICAL DETERMINATION OF DOPAMINE WITH GRAPHENE-MODIFIED GLASSY CARBON ELECTRODES

Two new glassy carbon modified electrodes were prepared by drop casting of chemically reduced graphene oxide (rGO) or graphene oxide (GO) on glassy carbon (GC) and then protected with a polymeric layer of Nafion or chitosan (Chit) (GC/Chit/rGO/Chit and GC/GO/Nafion). Their investigation by cyclic- and square-wave voltammetry for dopamine (DA) oxidation was aiming to estimate the analytical parameters that have the best values for GC/Chit/rGO/Chit electrode (i.e., the highest sensitivity of 1.002 +/- 0.025 mu A/mu M, a detection limit of 2.67 mu M mu M, for a linear domain from 4 to 18 mu M DA). The modified GC/Chit/rGO/Chit electrode was also used for the detection of dopamine in injection vials using the standard addition method with a recovery of 99.42%.