A Sensitive Voltammetric Sensor Based on Au Nanoparticle Decorated Graphene Nanosheets Modified Glassy Carbon Electrode for Determination of Acetylcholine in Presence of Dopamine

Abstract

In this study the electro oxidation of acetylcholine (ACh) in pH 7.0 phosphate buffer solution (PBS) was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) with the modified glassy carbon electrode (GCE) by Au nanoparticle decorated graphene nanosheets (Au NPs/GNs). DPV is a rapid and sensitive electro analytical technique for determination of acetylcholine in presence of dopamine (DA). Using DPV technique, the current was linear within a concentration range of 0.1-700.0 µM of acetylcholine. The detection limit of the method for acetylcholine is 0.04 µM (S/N=3). Diffusion coefficient, D, and charge transfer coefficients, α, have been determined for oxidizing acetylcholine at the modified surface. The applicability of the proposed method was shown by the successful analysis of acetylcholine in real sample.