Synergic Effect of Graphene Quantum Dots and Room Temperature Ionic Liquid for the Fabrication of Highly Sensitive Voltammetric Sensor for Levodopa Determination in the Presence of Serotonin Publisher



Sanati AL¹ ; Faridbod F¹ ; Ganjali MR^{1, 2} Show Affiliations
Source: Journal of Molecular Liquids Published:2017

Abstract

Levodopa, one of the prescribed medications in Parkinson disease, is electrochemically determined here. A room temperature ionic liquid/graphene quantum dots (GQDs) modified carbon paste electrode (RTIL-GQDs/CPE) was used for the electrochemical determination of levodopa. The electro-oxidation mechanism of levodopa at RTIL-GQDs/CPE was also studied. The obtained data showed that the electro-oxidation of levodopa at the RTIL-GQDs/CPE is greatly facilitated, which is attributed to high electrical conductivity of GQDs and RTIL. The electrochemical oxidation of levodopa at the RTIL-GQDs/CPE is a two proton–two electron process. The RTIL-GQDs/CPE showed a good electron mediating behavior followed by well separated oxidation signals of levodopa and serotonin. Square wave voltammetric peak current shows a linear relationship corresponds to the concentrations of levodopa in a linear range of 0.05 to 250.0 μM with detection limit of 10.0 nM. The RTIL-GQDs/CPE shows excellent ability to determination of levodopa in real samples. © 2017 Elsevier B.V.