Unidad de excelencia María de Maeztu MdM-2015-0552

This article reports a novel electrochemical recognition platform based on a nanocomposite carbon paste electrode containing carbon nanotubes modified with gold nanoparticles carrying a thiolated catechol for the fast amperometric determination of uranyl ion (UO ) in water. Recognition of UO is accomplished by supramolecular chemistry due to the formation of an inclusion complex between catechol and UO . The amperometric device operates at -0.40 V vs. Ag/AgCl, where the reduction of UO takes place on the electrode surface, covering a linear range from 0.49 to 170 μg L UO in a 0.1 M boric acid buffer solution at pH 5.3. The developed sensing system presents good response towards UO in aqueous environmental samples, with good selectivity over other browsed cations and can be easily reset by simple polishing. This platform has demonstrated to be a potential alternative regarding to the common standard bench-top analytical techniques for the development of in-field devices for in-situ monitoring.