Characterization of Low-Cost, Robust, Graphene-Based Amperometric Dot Microsensors for the Determination of Dopamine

Elderly individuals may develop neurological disorders such as Parkinson's and Alzheimer's. Therefore, there is a need to develop reliable, low-cost and robust amperometric microsensors for the determination of dopamine. This paper reports the evaluation of four amperometric dot microsensors based on graphene for dopamine in urine samples. The proposed designs were evaluated for cost, availability, and simplicity of construction, so that they are affordable in remote rural locations and for widespread screening. Ag, Cu, and stainless steel (SS) wires were proposed as electrical contacts and counter electrodes for the amperometric dot microsensors. The detection limits were between 1.94 x 10(-7) and 1.20 x 10(-8 )mol L-1 with sensitivities from 0.54 nA mu mol L-1 to 1.40 nA mu mol L-1. While the detection limits are comparable with the literature values, the sensitivities are higher for the proposed microsensors. Dopamine was recovered from urine in percentages exceeding 96% with relative standard deviations less than 3%.

Automated summary

This study developed graphene-based amperometric microsensors for detecting dopamine in urine samples, with high sensitivity and good recovery rate of dopamine, aiming at diagnosing neurological disorders in the elderly.