Voltammetric Determination of Xanthine with a Single‐Walled Carbon Nanotube‐Ionic Liquid Paste Modified Glassy Carbon Electrode

Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
Electroanalysis (Impact Factor: 2.82). 10/2007; 20(4):361 - 366. DOI: 10.1002/elan.200704042

ABSTRACT Single-walled carbon nanotube (SWNT) and room temperature ionic liquid (i.e., 1-butyl-3-methylimidazolium hexaflourophosphate, BMIMPF6) were used to fabricate paste modified glassy electrode (GCE). It was found that the electrode showed sensitive voltammetric response to xanthine (Xt). The detection limit was 2.0×10−9 M and the linear range was 5.0×10−9 to 5.0×10−6 M. The electrode also displayed good selectivity and repeatability. In the presence of uric acid (UA) and hypoxanthine (Hx) the response of Xt kept almost unchanged. Thus this electrode could find application in the determination of Xt in some real samples. The analytical performance of the BMIMPF6-SWNT/GCE was demonstrated for the determination of Xt in human serum and urine samples.

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