A new sensitive and selective sensor for heavy metal ions based on tannin extracted from the skin of Punica granatum L

摘要

This article presents the development of a sensor made from a gold electrode and a receiving polymeric membrane based on. tannin extracted from the skin of PLICIICCI granatUM. L (pomegranate) for real-time detection of heavy metals in a hydrous environment. The basic principle of this device is the complexing chelating) of metal ions through the adjacent hydroxyl groups contained in the chemical structures of the tannins. The electrochemical characterisation was performed by using electrochemical impedance spectroscopy and square wave voltammetry. Other morphological and structural analyses were performed by using Fourier transform infrared spectroscopy and atomic-force microcuPY. The results obtained showed the high sensitivity of the developed device (detection limits of 6.35 x 10(-9) g L-1 for Cu2+, 1.1 x 10(-8) g L-1 for Cd2+ and 2 x 10(-7) g L-1 for Pb2+) and the possibility of simultaneously detecting several heavy metals, each one in a highly selective manner with highly acceptable response time (48s).