A new electrochemical sensor based on a screen-printed electrode modified with an ion-imprinted PEDOT for the detection and the quantification of Cd(II)

In this study, an electrochemical sensor was developed using an ion imprinting technique to create a film, facilitating rapid, sensitive, cost-effective and multiplexed determination of cadmium ions in nature. Indeed, pollution by this substance is of great concern due to its toxic health risks and its cumulative and persistent nature in living organisms. The sensor was functionalized with cyclic voltammetry by directly electropolymerizing ethylenedioxythiophene (EDOT) in the presence of Cd(II) as a template on screen-printed platinum electrodes. After electropolymerization, the structure and the morphology of the sensor ion imprinted polyethylendioxythiophene (IIP-PEDOT/SPPtE) were characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and scanning electron microscopy (SEM/EDX). The electrochemical properties of the sensor were studied by cyclic voltammetry and electrochemical impedance spectroscopy. All experimental parameters were optimized by square wave voltammetry. IIP-PEDOT/SPPtE exhibited a linear concentration range of 0.5 to 75 µg/L, a detection limit of 0.07 µg/L and a quantification limit of 0.21 µg/L. Furthermore, the proposed sensor revealed good reproducibility, high stability and high selectivity for cadmium over several potential interferents. The developed device was successfully applied to the Cd(II) detection in industrial water samples via the standard addition method. The results were compared to analyzes of the same samples by ICP-MS. A high recovery rate of around 90–102.2 % and an RSD equal to 5.8 % and 2.5 % were observed.