Print Email Facebook Twitter Voltammetric Detection of Urea on an Ag-Modified Zeolite- Expanded Graphite-Epoxy Composite Electrode Title Voltammetric Detection of Urea on an Ag-Modified Zeolite- Expanded Graphite-Epoxy Composite Electrode Author Manea, F. Pop, A. Radovan, C. Malchev, P.G. Bebeselea, A. Burtica, G. Picken, S.J. Schoonman, J. Faculty Applied Sciences Department ChemE/Chemical Engineering Date 2008-09-22 Abstract In this paper, a modified expanded graphite composite electrode based on natural zeolitic volcanic tuff modified with silver (EG-Ag-Z-Epoxy) was developed. Cyclic voltammetry measurements revealed a reasonably fast electron transfer and a good stability of the electrode in 0.1 M NaOH supporting electrolyte. This modified electrode exhibited moderate electrocatalytic effect towards urea oxidation, allowing its determination in aqueous solution. The linear dependence of the current versus urea concentration was reached using square-wave voltammetry in the concentrations range of urea between 0.2 to 1.4 mM, with a relatively low limit of detection of 0.05 mM. A moderate enhancement of electroanalytical sensitivity for the determination of urea at EG-Ag-Z-Epoxy electrode was reached by applying a chemical preconcentration step prior to voltammetric/amperometric quantification. Subject urea determinationexpanded graphite-Ag-zeolite-epoxy composite electrodeelectrocatalytic effect To reference this document use: http://resolver.tudelft.nl/uuid:75ab7d41-fd77-4fdc-aab2-301d1a0ca59b DOI https://doi.org/10.3390/s8095806 Publisher MDPI AG ISSN 1424-8220 Source Sensors, 8 (9), 2008 Part of collection Institutional Repository Document type journal article Rights (c) 2008 The Author(s) Files PDF Malchev_2008.pdf 454.01 KB Close viewer /islandora/object/uuid:75ab7d41-fd77-4fdc-aab2-301d1a0ca59b/datastream/OBJ/view