Novel electrochemical sensing platform based on ion imprinted polymer with nanoporous gold for ultrasensitive and selective determination of As3.

Ma, Wuwei; Chang, Qigang; Zhao, Jinhu; Ye, Bang-Ce

An electrochemical sensor has been developed based on ion imprinted polymer (IIP) and nanoporous gold (NPG) modified gold electrode (IIP/NPG/GE) for determination of arsenic ion (As3+) in different kinds of water. NPG with high conductivity, large specific surface area, and high biocompatibility was prepared by a green electrodeposition method. Then a layer of IIP was synthesized in situ on NPG surface by electropolymerization, in which As3+ was used as template ion and o-phenylenediamine as functional monomer. We used potassium ferricyanide and potassium ferrocyanide chelates as electrochemical probes to generate signals. The electrochemical behavior of IIP/NPG/GE (vs. Ag/AgCl) was studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The linear range for As3+ was 2.0 × 10-11 to 9.0 × 10-9 M, and the lower detection limit was 7.1 × 10-12 M (S/N = 3). This newly developed sensor has good stability and selectivity, and has been successfully applied to the As3+ determination of four kinds of water quality.