Laboratory Made Electrochemical Sensors for Adsorptive Stripping Voltammetry

A novel method of adsorptive stripping voltammetry with a medium exchange preconcentration for the analytical detection of ferrocene in a small sample is presented. A laboratory prepared carbon paste electrode or a clay modified carbon paste electrode (referred to as a sensor) is used as a working electrode. The method consists of two principal steps: (1) nonelectrolytic preconcentration of the analyte of interest by adsorption /extraction from ethanolic solution, (2) quantitation of the surface confined analyte via anodic stripping differential pulse voltammetry in a conventional three electrode electrochemical cell with aqueous electrolyte solution. A visible enhancement of the voltammetric response of ferrocene and 100-fold increase in sensitivity is observed at the sensor, compared to the conventional carbon paste electrode. A possibility of electrode saturation is addressed.