A sol-gel method Immobilized Acetylcholinesterase biosensor for detecting Organophosphorus Pesticide Residues

摘要

In this paper, Acetylcholinesterase(AchE) employed homogenate from chicken brain home-made in laboratory. One kind of AChE immobilization method on surface of glassy carbon was studyed. The immobilization methods employed sol-gel method with tetraethoxysilane(TEOS). Chicken brain acetylcholinesterase was immobilized on ehitosan porous membrane with a filter pore size of 0.45μm. Then the enzyme membrane was fixed on the surface of glassy carbon electrode(GCE)to prepare an amperometric biosensor for the detection of organophosphorus pesticides. Immobilization chicken brain acetylcholinesterase activity was amperometric measured by the anodie oxidation of the thiocholine (TCh) produced by hydrolysis of the acetylthiocholine (ATCh) substrate in electrochemical workstation, the results of carrier materials comparation showed that the rate recovery activity of enzyme was high. Biosensor sensitivity and reproducibility were statistically evaluated for the different immobilization methods and the most suitable immobilization procedure was selected.