Development of An Eco-Friendly and Cost-Effective Electrochemical Sensor for the Simultaneous Detection of Dopamine and Serotonin

An electrochemical sensor based on eco-friendly green synthesized silver nanoparticles decorated reduced graphene oxide (AgNPs-rGO) modified screen-printed carbon electrode (SPCE) for the simultaneous detection of serotonin (5-HT) and dopamine (DA) is reported for the first time. The experimental parameters affecting the sensor performance were optimized in terms of AgNPs-rGO coating amount, scan rate and electrolyte pH (6-8). Under optimal conditions, the AgNPs-rGO/SPCE was employed to individually determine both analytes using DPV technique. The sensor was also efficient in the simultaneous detection of these species and reported well-resolved oxidation peaks with a linear range of 10-100 μM and detection limits of 7 µM and 7.41 µM, respectively. The developed device showed good selectivity, reproducibility, and repeatability. Furthermore, it was successfully applied to the determination of both biomolecules in artificial urine samples with good recovery. The main advantages of the designed sensor are its simplicity, portability, and low cost.