Development of carbon paste electrode modified with cadmium ion-imprinted polymer for selective voltammetric determination of Cd2+

A simple and fast voltammetric method based on a new electrode composed of carbon paste electrode/bifunctional hybrid ion imprinted polymer (CPE/IIP) was developed for the quantification of Cd2+ in water samples. The voltammetric measurements by Differential Pulse Voltammetry were performed by using CPE containing 11.0 mg of IIP under phosphate buffer solution at concentration 0.1 mol L-1 and pH 6.5. The electrochemical method was carried out by Cd2+ preconcentration at-1.2 V during 210 s, followed by anodic stripping. The performance of IIP towards Cd2+ determination was evaluated by comparison to non-imprinted polymer, whose detectability of IIP was much higher (45%). The sensitivity of the sensor was found to be 0.0105 mu A/mu g L-1. The limits of detection and limits of quantification were found to be 4.95 mu g L-1 and 16.4 mu g L-1, respectively. The developed method was successfully applied to Cd2+ determination in mineral, tap and lake water samples, whose results are in agreement with thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) used as reference analytical technique. According to achieved results, the developed method can be used for routine analysis of quality control of water samples from different sources.