Electrochemical Sensor Based on Reduced Graphene Oxide Incorporated with Magnetite and Silver Nanoparticles Composite Electrode for Determination of Dopamine

Dopamine determination has become crucial as the abnormal levels of dopamine can potentially cause psychological disorders as well as Parkinson's disease. Herein, a novel electrochemical sensing platform based on magnetite (Fe3O4), silver nanoparticles (AgNPs) and reduced graphene oxide (rGO) composite, denoted as rGO-Fe3O4/AgNPs was facilely synthesized using a modified Hummer's two-step synthesis and co-precipitation approach without the use of any other oxidants or stabilizers. This composite was designed as an electrochemical sensor for exceptionally sensitive DA detection in human urine samples. The microscopic study of the composite revealed that the Fe3O4 and AgNPs were extensively decorated onto the rGO surface. The optimized scan rate of 100 mV s(-1) and neutral pH of the supporting electrolyte for the composite-modified electrode was further used to determine dopamine (DA) in human urine samples. DA displayed an anodic peak at 0.20 V vs Ag/AgCl (3.0 mol l(-1) KCl) utilizing differential pulse voltammetry technique. With detection limits of 3.98 nM, the analytical curves obtain a wide range of linear from 0.015 mu M to 100 mu M. The designed sensor had several advantages, including ease of preparation, low cost of nanomaterials utilized, and rapid response.

Automated summary

A novel electrochemical sensing platform based on Fe3O4, silver nanoparticles (AgNPs), and reduced graphene oxide (rGO) composite was synthesized for sensitive dopamine (DA) detection in human urine samples. The optimized composite-modified electrode showed anodic peak of DA at 0.20 V vs Ag/AgCl and detection limits of 3.98 nM, with a linear range from 0.015 μM to 100 μM. The sensor offers advantages such as ease of preparation, low cost, and rapid response.