The Contribution of Polyaniline and Gold Nanoparticles for Enhancing Signals of Streptavidin Based Immunosensor

Abstract

The presence of streptavidin has been found to serve as an electrically insulating layer. This could reduce the initial current response of an electrochemical immunosensor, reducing its performance for detecting the analyte of interest. The work aimed to investigate the current response of the streptavidin based electrochemical immunosensor at polyaniline and gold nanoparticle modified screen-printed electrodes and compare to without gold nanoparticle addition. The result of the streptavidin modified gold nanoparticles - polyaniline sensor exhibited a three-times higher current response than that of the streptavidin modified polyaniline sensor (without gold nanoparticle). Additionally, antibody immobilization (EpCAM as a model) on the modified electrode showed high performances for use further in antigen target detection. The high conductivity of the developed immunosensor could become a promising candidate for immunosensor development with high sensitivity in the future.