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

Abstract

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 10⁻⁸mol L⁻¹ with sensitivities from 0.54 nA µmol L⁻¹ to 1.40 nA µmol 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%.

Keywords:

• Amperometric dot microsensor
• dopamine
• graphene

Additional information

Funding

This work was supported by UEFISCDI, PNII Program Ideas 2012-2014, Contract nr. 100/27.10.2011.