ION-EXCHANGE VOLTAMMETRY OF CATIONIC SPECIES AT MEMBRANE CLAY-MODIFIED ELECTRODES

Membrane glassy carbon electrodes modified with clay (laponite, montmo rillonite, beidellite under a commercial drug form) suspensions. entra pped between a dialysis membrane and the carbon surface, were used in the ion-exchange voltalmmetry of methylviologen MV2+ and cationic comp lex Cu/NH3)(4)(2+). Various parameters (concentration of the clay susp ension, pH, stability, limit of detection) were investigated. This stu dy has been extended to other metal cations of environmental interest. The feasibility of such suspension-modified electrodes for an approac h to the analytical investigation of delaminated clays is underlined.