I have read many papers where they use HRP with Gold Nanoparticles for detecting Hydrogen peroxide in amperometric sensing systems. Both HRP and Gold Nanoparticles can detect Hydrogen peroxide. In those papers they said, HRP reacts with H2O2, and Gold Nanoparticles are used to enhance the catalytic activity. They proved their explanation through cyclic Voltammetry results. I want to know the explanation behind this theory. Why Gold Nanoparticles did not react with H2O2 in the presence of HRP?