Among these methods, ETs based on enzyme-based biosensors have attracted growing interests due to their high-sensitivity,portability, low cost and short analytical time. Although various kinds of biosensors for H2O2 detection have been developed based on electrocatalytic reduction of H2O2 using horseradish peroxidase (HRP) , it is still very necessary to fabricate the sensitive H2O2 biosensor exhibiting long-term stability. Usually,