Overoxidized poly(3,4-ethylenedioxythiophene)–gold nanoparticles–graphene-modified electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid

作者：Junqiang Pan, Mei Liu, Dandan Li, Haonan Zheng, Dongdong Zhang · 发表于：Journal of Pharmaceutical Analysis · 年份：2021 · DOI：10.1016/j.jpha.2021.09.005 · 被引用次数：38 · 研究领域：Electrochemical sensors and biosensors、Conducting polymers and applications、Electrochemical Analysis and Applications

An innovative, ternary nanocomposite composed of overoxidized poly(3,4-ethylenedioxythiophene) (OPEDOT), gold nanoparticles (AuNPs), and electrochemically reduced graphene oxide (ERGO) was prepared on a glassy carbon electrode (GCE) (OPEDOT-AuNPs-ERGO/GCE) through homogeneous chemical reactions and heterogeneous electrochemical methods. The morphology, composition, and structure of this nanocomposite were characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electrochemical properties of the OPEDOT-AuNPs-ERGO/GCE were investigated by cyclic voltammetry using potassium ferricyanide and hexaammineruthenium(III) chloride redox probe systems. This modified electrode shows excellent electro-catalytic activity for dopamine (DA) and uric acid (UA) under physiological pH conditions, but inhibits the oxidation of ascorbic acid (AA). Linear voltammetric responses were obtained when DA concentrations of approximately 4.0-100 μM and UA concentrations of approximately 20-100 μM were used. The detection limits (S/N=3) for DA and UA were 1.0 and 5.0 μM, respectively, under physiological conditions and in the presence of 1.0 mM of AA. This developed method was applied to the simultaneous detection of DA and UA in human urine, where satisfactory recoveries from 96.7% to 105.0% were observed. This work demonstrates that the developed OPEDOT-AuNPs-ERGO ternary nanocomposite, with its excellent ion-selectivit...