Immobilized enzyme has an important impact on sensitivity and stability of organophosphorus hydrolase biosensor

which is a new kind of detection device for detecting organophosphorus pesticide residues in agricultural products.The impact of carrier-bound type

pore size as well as enzyme immobilized methods/ways and means on the diversification capacity of pH are studied.The results show that the diversification capacity of pH caused by 0.45 μm nitrocellulose membrane is better than other carrier-bound types;immersion ways is greater than titration;the immobility ability of bovine serum albumin-glutaraldehyde cross-linking method is better than both simple physical adsorption and bovine serum albumin（BSA）immobilization method

and the best result is got when the volume fraction of glutaraldehyde and BSA is 2.5 % and 10 % respectively.