Electroanalysis of Trace Inorganic Arsenic with Gold Nanoelectrode Ensembles

Abstract

The results of a study on the determination of trace levels of arsenic with nanoelectrode ensembles (NEEs) are reported. In order to lower the detection limit and to increase the number of performable analysis for each NEE, the right choice of the supporting electrolyte concentration and electroanalytical parameters were optimized. The electrochemical behavior of As(III) at NEEs was studied at first by cyclic voltammetry, while trace concentrations of As(III) were determined by anodic stripping square wave voltammetry. The method is characterized by a detection limit as low as 5 ng/L (65 pM) after 3 min preconcentration at À0.4 V. Finally, NEEs were applied to trace As analysis in real samples such as certified seawater samples.

Arrays of copper nanowire electrodes: Preparation, characterization and application as nitrate sensor

“…The largest part of these studies was developed using ensembles of gold nanoelectrodes (NEEs) prepared via electroless deposition. From an analytical viewpoint, metals different from Au were seldom studied, with few exceptions such as for instance, Bi modified NEEs [8], applied for ultratrace lead (II) analyses. Recently, a simple and effective electrodeposition method for obtaining copper NEEs was proposed [9], where copper is an interesting electrode material suitable for the detection of analytes electroactive at negative potential values.…”

Electrochemical determination of inorganic mercury and arsenic—A review

“…compared GNEE on basal-plane graphite modified electrode with GNEE on glassy carbon and macro gold electrode and found that the former had higher sensitivity(Dai and Compton 2005) Mardegan et al, (2012). reported a detection limit of 0.005µg/L with gold nano electrode ensemble (Au-NEE)(Mardegan et al 2012) Kamenev et al, (2001). reported graphite electrodes modified with gold and copper with detection limit of 17µg/L and 47µg/L respectively(Kamenev et al 2001), whereas a better detection limit (7µg/L) was obtained with gold-graphite electrode(Kamenev et al 2005) Beinrohr (2001)(Beinrohr 2001).…”

“…compared GNEE on basal-plane graphite modified electrode with GNEE on glassy carbon and macro gold electrode and found that the former had higher sensitivity(Dai and Compton 2005) Mardegan et al, (2012). reported a detection limit of 0.005µg/L with gold nano electrode ensemble (Au-NEE)(Mardegan et al 2012) Kamenev et al, (2001).…”

Inorganic arsenic speciation by electroanalysis. From laboratory to field conditions: A mini-review

“…For example, LODs in the range 0.01-0.05 ppb are presented in [26,[36][37][38][39][40][41][42] and LOD lower than 0.005 ppb in [43][44][45][46][47][48]. A number of different approaches have been used to improve the sensitivity of detection:…”