| Full text | |
| Author(s): |
Arguello, Jacqueline
[1]
;
Leidens, Victor L.
[1]
;
Magosso, Herica A.
[1]
;
Ramos, Rodrigo R.
[1]
;
Gushikem, Yoshitaka
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Estadual Campinas, Inst Quim, BR-13084971 Campinas, SP - Brazil
Total Affiliations: 1
|
| Document type: | Journal article |
| Source: | Electrochimica Acta; v. 54, n. 2, p. 560-565, DEC 30 2008. |
| Web of Science Citations: | 76 |
| Abstract | |
This paper describes the preparation, characterization and application of a composite electrode based on methylene blue adsorption to phosphorylated zirconia-silica mixed oxide particles prepared by a sol-gel process. This electrode electrocatalytically oxidizes ascorbic acid (AA), dopamine (DA) and uric acid (UA), allowing their simultaneous voltammetric detection. Well-defined and -separated oxidation peaks were observed by differential pulse voltammetry in a 0.35 mol l(-1) Tris-HCl buffer solution (pH 7.4) containing 0.5 mol l(-1) KCl. The anodic peak currents observed at -74, 94 and 181 mV increased with increasing concentrations of AA, DA and UA, respectively. Linear calibration plots were obtained over the range of 100-1600 mu mol l(-1) for ascorbic acid, 6-100 mu mol l(-1) for dopamine and 22-350 mu mol l(-1) for uric acid with detection limits of 8.3 +/- 0.1, 1.7 +/- 0.1 and 3.7 +/- 0.2 mu mol l(-1), respectively. DA and UA concentrations could also be determined under conditions of excess AA (1 mmol l(-1)). (c) 2008 Elsevier Ltd. All rights reserved. (AU) | |
| FAPESP's process: | 00/11103-5 - Porous materials: preparation, properties and applications |
| Grantee: | Yoshitaka Gushikem |
| Support Opportunities: | Research Projects - Thematic Grants |