Poly(aniline-co-o-anisidine)/graphene oxide Au nanocomposites for dopamine electrochemical sensing application

Abstract

We describe here the manufacture of poly(aniline-co-o-anisidine)/graphene oxide nanocomposites, with the common abbreviation [PANI-co-PoAN/GO1−5], by the well-known in situ oxidative polymerization method with ultrasonic assistance. FE-SEM and TEM micrographs were utilized to examine the morphological characteristics of the composite materials. Moreover, FT-IR, XRD, TGA, and electrical conductivity measurements were used to investigate their complete performance. All the composites had almost equal final copolymer decomposition temperatures, which were in the range of 609.3–663.8 °C. Our essential objective is to study the electro selective application using gold nanoparticles (AuNPs) as a coating. Dopamine (DA) electrochemical sensor based on [AuNPs/PANI-co-PoAN/GO] nanocomposite covalently modified gold electrode was modified by an electroabsorption technique. The electrochemical behavior of the modified electrode towards the oxidation of DA was studied by square wave voltammetry (SWV) and cyclic voltammetry (CV) in pH 5.0 phosphate buffer solution. The sensor developed a current response to the oxidation of DA. Using SWV, the electrochemical sensor gave a linear relationship to DA in the concentration range of 5–100 µM with a limit of detection of 0.0334 µM. The modified electrode was highly stable, sensitive, and selective.