▎ 摘　　要

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%.