| Organophosphorus pesticides are wildly used in agriculture, industry, medicine etc and lead to a series of problems of environmental pollution and food contamination. The major organophosphorus pesticides have strong toxicity. Contacting with organophosphorus pesticides and absorbing by skin, respiratory system and gastrointestinal tract lead to severe disease. One of the most important preventive measures in this case is to rapidly and accurately determine the residues of organophosphorus pesticides in real samples. In recent years, there were some reports about the fast determination to organophosphorus residue. This article was based on enzyme inhibition principle and used biosensors technique and spectrophotometry to determine organophosphorus residue. It was devided into four sections below: 1. The methods of determination to organophosphorus residue were reviewed. The major methods were: spectrum, chromatograph, enzyme inhibition, immunology and biological chip etc. Spectrum and chromatograph were the major methods to determine organosphorus pesticides, enzyme inhibition was better for the grass-root unit to use, immunology and biological chips represent the developing derection of the study field. 2. Acetylcholinesterase was cross-linked on an acellulose acetate membrance and assembled to biosensors. The determination conditions were optimized such as immobilization amount of enzyme, substrate concentration and buffer solution acidity. It was found that, when in the concentration range of 3.43×10-10～3.43×10-5 mol/L, inhibition percentage versus logarithm of parathion concentration were linear and detection limit was 2.45×10-10 mol/L. The method presented in this paper had been applied in the determination of parathion in vegetables with satisfactory results. 3. Acetylcholinesterase was extracted from chicken brain by a simple, effective method. The activity of enzyme was tested by national standard method and got a...
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