Electrodeposition of gold nanoclusters on overoxidized polypyrrole film modified glassy carbon electrode and its application for the simultaneous determination of epinephrine and uric acid under coexistence of ascorbic acid

• Published in: Analytica chimica acta Vol. 596; no. 2; pp. 222 - 230
• Main Authors: Li, Jing, Lin, Xiang-Qin
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 23.07.2007; Elsevier
• Subjects: Analytical chemistry; Animals; Ascorbic Acid - analysis; Biological and medical sciences; Biosensors; Biotechnology; Carbon - chemistry; Cattle; Chemistry; Electrochemical deposition; Electrochemical methods; Electrodes; Electroplating - methods; Epinephrine; Epinephrine - analysis; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Gold - chemistry; Gold nanoclusters; Humans; Metal Nanoparticles - chemistry; Methods. Procedures. Technologies; Overoxidized polypyrrole; Oxidants - chemistry; Polymers - chemistry; Pyrroles - chemistry; Spectrometric and optical methods; Uric acid; Uric Acid - analysis; Various methods and equipments; Electrochemical deposition; Epinephrine; Gold nanoclusters; Uric acid; Overoxidized polypyrrole; Ascorbic acid; Electrochemical method; Voltammetry; X ray; Selectivity; Powder; Hydrochlorides; Detection limit; Electrodeposition; Photoelectron spectrometry; Nanocomposite; Oxidation; Ultrathin films; Urine; Scanning electron microscopy; Gold; Catalytic reaction; Stability; Differential impulse voltamperometry; Carbon electrode; X ray spectrometry; X ray diffraction; Sensitivity; Biosensor; Thin layer electrode; Simultaneous measurement; Pyrrole polymer
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2007.05.057

A novel biosensor was fabricated by electrochemical deposition of gold nanoclusters on ultrathin overoxidized polypyrrole (PPyox) film, formed a nano-Au/PPyox composite on glassy carbon electrode (nano-Au/PPyox/GCE). The properties of the nanocomposite have been characterized by field emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD) and electrochemical investigations. The nano-Au/PPyox/GCE had strongly catalytic activity toward the oxidation of epinephrine (EP), uric acid (UA) and ascorbic acid (AA), and resolved the overlapping voltammetric response of EP, UA and AA into three well-defined peaks with a large anodic peak difference. The catalytic peak currents obtained from differential pulse voltammetry increased linearly with increasing EP and UA concentrations in the range of 3.0 × 10 −7 to 2.1 × 10 −5 M and 5.0 × 10 −8 to 2.8 × 10 −5 M with a detection limit of 3.0 × 10 −8 and 1.2 × 10 −8 M ( s/n = 3), respectively. The results showed that the modified electrode can selectively determine EP and UA in the coexistence of a large amount of AA. In addition, the sensor exhibited excellent sensitivity, selectivity and stability. The nano-Au/PPyox/GCE has been applied to determination of EP in epinephrine hydrochloride injection and UA in urine samples with satisfactory results.