fabricated by a layer-by-layer assembly immobilizing the GO nanosheets onto capillary wall.The characterization on the colomn was carried out by measuring the electro osmotic flow(EOF) and Raman spectrum,etc.Based on this,an about 1 cm length of capillary electrochromatography trypsin micro-reactor was prepared by immobilizing the trypsin on end of capillary column through ion bonding.The performance of this technique was investigated.Results showed that the introduction of GO to the capillary column not only improved its separation efficiency on sample,but also promoted its enzyme catalytic performance.The separation degree of the GO-coated capillary on a mixture of N-benzuyl-L-arginine ethyl ester hydrochloride(BAEE) and N-benzuyl-L-arginine(BA) was increased from 3.70 to 4.71 compared with that of bare capillary.Meanwhile,the enzyme activity of immobilized enzyme with GO as carrier(Michaelis constant Km=1.10 mmol/L,the maximum reaction rate Vmax=0.32 mmol?L-1?s-1) was also enhanced significantly compared with that of the immobilized enzyme on unmodified capillary(Km=109.77 mmol/L,Vmax=0.000 46 mmol?L-1?s-1.The prepared trypsin micro-reactor was finally employed as a model for the screening of enzyme inhibitors from ten kinds of herbs in the crude extracts.Results showed that the Pseudo-ginseng and the Rheum officinale both contained trypsin inhibitor activity,which indicated that the prepared enzyme immobilized micro-reactor is a potential tool for rapid inhibitor screening.