Voltammetric Determination of Dopamine in the Presence of Caffeine Using a Modified Glassy Carbon Electrode

— In this work, an electrochemical sensor based on CuO nanoflowers modified glassy carbon electrode (GCE) was developed for the voltammetric determination of dopamine. The CuO nanoflowers modified GCE showed good catalytic ability for the determination of dopamine. The differential pulse voltammetry investigation showed a linear relation between the dopamine current and its concentration within the range of 0.1–800.0 μM, with a limit of detection of 0.03 ± 0.001 μM. Also, the modified electrode was used for the simultaneous determination of dopamine and caffeine. Both dopamine and caffeine exhibited non-overlapping voltammetric peaks at 235 and 1390 mV, respectively, using CuO nanoflowers/GCE. Finally, the analytical performance of the developed sensor was evaluated for the analysis of dopamine and caffeine in real samples, which showed satisfactory results.