Facile synthesis of graphene oxide/Fe3O4 nanocomposite for electrochemical sensing on determination of dopamine

Dopamine concentration abnormalities in the body can cause various disorders and diseases such as Parkinson's, Tourette's syndrome, and depression. In this study, graphene oxide (GO) was combined with Fe3O4 to sensitively and selectively detect dopamine. The performance was evaluated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. The results of testing with CV on the solution [Fe(CN)6] showed that a modification with GO gave a maximum effective surface area value of 0.0127 cm2, proving that GO can increase the effective area and conductivity of the sensor. DPV testing shows that dopamine detection using GO/Fe3O4 has a linear range at a concentration of 1–10 μM with a detection limit of 0.48 μM and a quantification limit of 1.6 μM. GO/Fe3O4 also shows good selectivity where the peak current is separated by 0.245 V with ascorbic acid, which is the closest interference compound.