Selective Detection of Dopamine in the Presence of Uric Acid Using NiO Nanoparticles Decorated on Graphene Nanosheets Modified Screen-printed Electrodes

A convenient, low cost, and sensitive electrochemical method, based on a disposable graphene nanosheets (GR) and NiO nanoparticles modified carbon screen printed electrode (NiO/GR/SPE), is described for the simultaneous determination of dopamine (DA) and uric acid (UA). The modified electrode exhibited good electrocatalytic properties toward the oxidation of DA and UA. A peak potential difference of 150 mV between DA and UA was large enough to determine DA and UA individually and simultaneously. The anodic peak currents of DA were found to be linear in the concentration range of 1.0-500.0 mu M with the detection limit of 3.14 x 10(-7) M.