Bowl-shaped graphene oxide/Fe3O4 composites on Au-PCB electrode for electrochemical detection of dopamine

A novel bowl-shaped GO/Fe3O4 composite with large specific surface area was prepared by cold quenching. Remarkably, bowl-shaped GO/Fe3O4 composites on gold printed circuit board (Au-PCB) electrode exhibited a high electrochemical activity towards the detection of dopamine, which displayed an oxidation peak at 0.45 V due to the oxidation of dopamine to dopamine-o-quinone and a reduction peak at 0.37 V derived from the reduction of dopamine-o-quinone to dopamine. The interaction between GO/Fe3O4 composites and dopamine can be strengthened via π-π stacking forces and electrostatic interactions due to the aromatic rings of graphene oxide (GO) and H-bonding via the functional groups of dopamine. The lower limit of detection (LOD) for dopamine was found to be about 0.023 μМ. The GO/Fe3O4 composite showed excellent sensitivity in dopamine detection in the presence of ascorbic acid and uric acid. Therefore, the GO/Fe3O4 composite modified Au-PCB electrode for the detection of dopamine could be achieved in practical applications.