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

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.