The enzymatic probe based on nano-bioconjugate have been studied extensively for many years for their novel electronic, photonic and electrochemical properties. This review summarizes major advances in the gold nanoparticles(GNPs) biocongjugate probes to detect enzyme activity. This is followed by a discussion of the assays in colorimetric, fluorescence and other assays. Throughout the review, a detailed explanation of the unique designs will be presented, and the benefits and shortcomings of these approaches will be highlighted. The review concludes with a brief perspective on future research directions, and remaining barriers that must be overcome for the successful application of these technologies.

Contents
1 Introduction
2 Principle of enzyme activity detection based on GNPs
2.1 Colorimetric assays
2.2 FRET-based assays
2.3 Other assays
3 Neglected enzymes in the field of sensors
4 Conclusion