As an ideal electrode material with excellent physical and chemical properties, graphene has been widely concerned in electrocatalysis and electroanalytical applications. It may be limited by the great in the electrochemical application areas due to its irreversible agglomeration. However, it is well realized that graphene oxide can provide a new way to separate graphene sheets for the reason of its good hydrophilic characteristic and also that the preparation of graphene oxide usually is simple and easy. But the electron transmission capacity of the modified interface based on graphene oxide would be further decreased due to its oxygen-containing groups, which are not benefited for the eletrocatalysis and electrochemical sensors with high sensitivity. Additionally, oxygen-containing groups of graphene oxide can be reduced by using some reduction methods so as to restore a more perfect graphene structure with planar conjugated, which will further improve the conductivity and adjust the band gap of graphene oxide. Therefore the electro-catalytic properties of the resulting materials can be adapted by using such reduction methods. Electrochemical sensors based on electrochemical reduced graphene oxide (ERGO) have been widely applied in all kinds of electrcatalytic and electrochemical sensor research fields due to its unique characteristic and advantages. In this paper, the recent progress of electrochemical sensor based on ERGO materials are briefly reviewed, including the characteristics, preparation principle and methods, classification of such electrochemical sensing platform and, also its applications as electrochemical sensing in the field of environmental pollutants, the food and drug, DNA and biological analysis. In addition, the future development and application prospect of this kind of ERGO based electrochemical sensors were further discussed.

Contents
1 Introduction
2 Preparation of ERGO modified electrodes
2.1 Indirect electrochemically reduced method
2.2 Direct electrochemically reduced method
3 Classification of ERGO modified electrodes
3.1 Intrinsical ERGO modified electrodes
3.2 The composite modified electrodes based on inorganic nanoparticles and ERGO
3.3 The composite modified electrodes based on organic compounds and ERGO
3.4 The composite modified electrodes based on inorganic-organic and ERGO
4 Electrocatalytic and electrochemical applications of ERGO modified electrodes
4.1 Electrochemical analysis of small molecules
4.2 Electrochemical analysis of molecules containing aromatic structure
4.3 Electrochemical analysis of biological molecules (protein and DNA)
5 Conclusion and outlook