Original scientific paper

https://doi.org/10.5562/cca1976

Electrochemical Behaviors and Sensitive Determination of Guanosine-5’-monophosphate on Ionic Liquid Modified Carbon Paste Electrode

Wei Sun orcid.org/0000-0002-9923-7328 ; College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, P. R. China
Li Xu ; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China
Jun Liu ; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China
Xiuzhen Wang ; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China
Song Hu ; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
Jun Xiang ; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China

Abstract

A new electrochemical sensor was fabricated by using ionic liquid (IL) 1-octyl-3-methylimid- azolium hexafluorophosphate (OMIMPF6) modified carbon paste electrode (denoted as IL-CPE). The electrode was characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. Due to the presence of high conductive IL in the carbon paste electrode, IL-CPE exhibited excellent electrocatalytic ability to the oxidation of guanosine-5’-monophosphate (GMP) with the increase of the oxidation peak current. A single well-defined irreversible oxidation peak appeared at +1.14 V in a B-R buffer of pH=5.0 with adsorption-controlled process. The electrochemical reaction parameters of GMP oxidation were calculated with the electron transfer coefficient (α) as 0.32, the apparent heterogeneous electron transfer rate constant, ks=9.14×10–5s–1 and the surface coverage, ГT=2.34×10–9 molcm–2. Under the selected conditions the oxidation peak current was proportional to GMP concentration over the range from 1.0 to 1000.0 μmol dm–3 with the detection limit as 0.16 μmol dm–3 (3σ) by differential pulse voltammetry. The proposed method was further applied to determine the GMP contents in artificial samples and chicken powder samples with satisfactory results. (doi: 10.5562/cca1976)

Keywords

carbon ionic liquid electrode; guanosine-5’-monophosphate; cyclic voltammetry; differential pulse voltammetry; 1-octyl-3-methylimidazolium hexafluorophosphate

Hrčak ID:

105036

URI

https://hrcak.srce.hr/105036

Publication date:

1.7.2013.

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