title: Polypyrrole and graphene quantum dots @ Prussian Blue hybrid film on graphite felt electrodes: Application for amperometric determination of l-cysteine.
abstract: A novel polypyrrole (PPy) and graphene quantum dots (GQDs) @ Prussian Blue (PB) nanocomposite has been grafted on a graphite felt (GF) substrate (PPy/GQDs@PB/GF), and has been proven to be an efficient electrochemical sensor for the determination of l-cysteine (l-cys). GQDs, which were fabricated by carbonization of citric acid and adsorbed on GF surface ultrasonically, played an important role for promoting the synthesis process of PB via a spontaneous redox reaction between Fe(3+) and [Fe(CN)6](3-). The PPy film has been electro-polymerized to improve the electrochemical stability of the PPy/GQDs@PB/GF electrode. The as-prepared electrode was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared spectroscopy (IR), X-ray diffraction (XRD) and electrochemical methods. It exhibited an excellent activity for the electrocatalytic oxidation of l-cys, with a detection sensitivity equal to 0.41 Amol(-1) L for a concentration range of 0.2-50 μmolL(-1), and equal to 0.15 Amol(-1) L for a concentration range of 50-1000 μmolL(-1). A low detection limit of 0.15 μmolL(-1), as well as a remarkable long-time stability and a negligible sensitivity to interfering analytes, were also ascertained.
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Laboratoire de Physique et Chimie de Nano-Objets, INSA, CNRS, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France.
authors.forename: Simon
authors.initials: S
authors.lastname: Tricard
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China.
authors.forename: Pengwei
authors.initials: P
authors.lastname: Yue
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China. Electronic address: zhaojihua@lzu.edu.cn.
authors.forename: Jihua
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China. Electronic address: fangj@lzu.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Fang
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China; School of Chemistry and Chemical Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Shen
mesh_terms: D003217:Conductometry / Q000295:instrumentation*; D003545:Cysteine / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005295:Ferrocyanides / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D008839:Microelectrodes; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D045663:Quantum Dots; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D005295:Ferrocyanides; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D006108:Graphite; D003545:Cysteine; C000170:ferric ferrocyanide
keywords: Biosensors; Graphene quantum dots; L-cysteine; Polypyrrole; Prussian Blue