title: Mercury(II) trace detection by a gold nanoparticle-modified glassy carbon electrode using square-wave anodic stripping voltammetry including a chloride desorption step.
abstract: Gold nanoparticles (AuNPs) were deposited on a glassy carbon (GC) substrate by constant potential electrolysis and characterized by cyclic voltammetry in H2SO4 and field emission gun scanning electron microscopy (FEG-SEM). The modified AuNPs-GC electrode was used for low Hg(II) concentration detection using a Square Wave Anodic Stripping Voltammetry (SWASV) procedure which included a chloride desorption step. The comparison of the obtained results with our previous work in which no desorption step was used showed that this latter step significantly improved the analytical performances, providing a three time higher sensitivity and a limit of detection of 80pM for 300s preconcentration, as well as a lower average standard deviation. The influence of chloride concentration on the AuNPs-GC electrode response to Hg(II) trace amounts was also studied and its optimal value confirmed to be in the 10(-2)M range. Finally, the AuNPs-GC electrode was used for the determination of Hg(II) in a natural groundwater sample from south of France. By using a preconcentration time of 3000s, a Hg(II) concentration of 19±3pM was found, which compared well with the result obtained by cold vapor atomic fluorescence spectroscopy (22±2pM).
authors.affiliation: Université de Toulouse, UPS, INPT, Laboratoire de Génie Chimique, 118 route de Narbonne, F-31062 Toulouse, France; CNRS, Laboratoire de Génie Chimique, F-31062 Toulouse, France; Université de Toulouse, INPT, LCA (Laboratoire de Chimie Agro-industrielle), UMR 1010, ENSIACET, 4 allée Emile Monso, F-31030 Toulouse CEDEX 4, France; INRA, LCA (Laboratoire de Chimie Agro-industrielle), F-31030 Toulouse, France; FCS RTRA "Sciences et Technologies pour l'Aéronautique et l'Espace", 23 avenue Edouard Belin, F-31400 Toulouse, France.
authors.forename: Laure
authors.initials: L
authors.lastname: Laffont
authors.affiliation: Université de Toulouse, UPS, INPT, Laboratoire de Génie Chimique, 118 route de Narbonne, F-31062 Toulouse, France; CNRS, Laboratoire de Génie Chimique, F-31062 Toulouse, France.
authors.forename: Teddy
authors.initials: T
authors.lastname: Hezard
authors.affiliation: Université de Toulouse, UPS, INPT, Laboratoire de Génie Chimique, 118 route de Narbonne, F-31062 Toulouse, France; CNRS, Laboratoire de Génie Chimique, F-31062 Toulouse, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Gros
authors.affiliation: Université de Toulouse, UPS, Géosciences Environnement Toulouse, 14, avenue Edouard Belin, F-31400 Toulouse, France; CNRS, Géosciences Environnement Toulouse, F-31400 Toulouse, France.
authors.forename: Lars-Eric
authors.initials: LE
authors.lastname: Heimbürger
authors.affiliation: Université de Toulouse, UPS, Géosciences Environnement Toulouse, 14, avenue Edouard Belin, F-31400 Toulouse, France; CNRS, Géosciences Environnement Toulouse, F-31400 Toulouse, France.
authors.forename: Jeroen E
authors.initials: JE
authors.lastname: Sonke
authors.affiliation: Université de Toulouse, INPT, LCA (Laboratoire de Chimie Agro-industrielle), UMR 1010, ENSIACET, 4 allée Emile Monso, F-31030 Toulouse CEDEX 4, France; INRA, LCA (Laboratoire de Chimie Agro-industrielle), F-31030 Toulouse, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Behra
authors.affiliation: Université de Toulouse, UPS, INPT, Laboratoire de Génie Chimique, 118 route de Narbonne, F-31062 Toulouse, France; CNRS, Laboratoire de Génie Chimique, F-31062 Toulouse, France. Electronic address: evrard@chimie.ups-tlse.fr.
authors.forename: David
authors.initials: D
authors.lastname: Evrard
mesh_terms: D002244:Carbon / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D004867:Equipment Design; D005602:France; D006046:Gold; D060587:Groundwater / Q000032:analysis; D008628:Mercury / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002712:Chlorides; D014874:Water Pollutants, Chemical; D002244:Carbon; D006046:Gold; D008628:Mercury
keywords: Chloride desorption step; Gold nanoparticles; Hg(II) sensor; Natural water; Stripping voltammetry