Voltammetric Microsystem for Trace Elements Monitoring

Abstract

The development of a voltammetric microsystem for monitoring and speciation studies of trace elements in natural waters is presented. This system was designed to provide an efficient coupling of the square-wave anodic stripping voltammetry (SWASV) detection with the permeation liquid membrane (PLM) technique. It consists of a voltammetric microcell, based on a gel-integrated Ir(Hg) micro-disk array, a PLM and two micromachined channels for the sample and strip solutions respectively. The analytical performance of the microsystem was first assessed for Pb(II) and Cd(II) and then the simultaneous accumulation and detection of Cd(II), Pb(II) and Cu(II) from a synthetic sample solution was performed. The estimated detection limit of the free metal ion is 2 pM for Pb(II) and 75 pM for Cd(II) using 5 min as deposition time.

Numerical simulations of linear scan anodic stripping voltammetry at a modified square array of hemispherical microelectrodes located in a thin-layer cell

“…1). It has been shown that such a gel not only protects the electrode against unspecific interferences, but it may also be chemically modified in order to obtain specific properties beneficial for voltammetric measurements [8][9][10]. Such GIME or analogous systems are thus very promising for analysis in complicated media.…”

“…Recently, we developed a microcell coupling the permeation liquid membrane (PLM) technique with voltammetric detection for trace metal speciation [10][11][12]. Briefly, the metals are transported from an aqueous test solution through the PLM by carrier-aided transport, to finally become chemically accumulated into a so-called strip solution [12,13].…”

Recent Developments in Stripping Analysis on Microelectrodes

“…Some selected applications to detect Zn, Pb, Cd, Cu and Tl(I) in aquatic systems are reported in refs. [142][143][144][145][146][147][148].…”

Microelectrode Arrays and Microfabricated Devices in Electrochemical Stripping Analysis

“…Microanalytical systems can be defined as systems where the sample preparation and detection are integrated in a single device. Buffle's group has been heavily involved in this area [48,86,87].…”