The Study Of The Techniques About Preparation And Chromatographic Determination To The Organophosphorus Pesticides In Foods

Due to the banning of bulk organochlorine pesticides, organophosphorus pesticides (OPs) have used more frequently for its relatively low persistence. At present, more than one hundred organophosphorus pesticides have been applied. For some metabolites are more toxic than their parent pesticides, their residues in foods are of great influence to human. So the analysis of OPs residue in the food is of great significance.Because extracting and purifying the trace pesticides in complex samples has direct effect on the accuracy of analytic results, it is taken into account firstly in progress of the pesticide residue analysis. Moreover the purer sample was the premiss in the common determination methods, for example, Gas Chromatography, Liquid Chromatography and Gas Chromatography-Mass Spectrum. Otherwise the residue analyses will be interfered by the complicated matrixes and the instruments will be damaged. So sampling, conisntraction and purification are important preparation steps in the analyses of pesticides residue. In this research, the study of the techniques of preparation and determination of OPs in foods were described.This paper is consisted of four parts.The progress of the determination methods for pesticides were described in the first part.The techniques preparation and determination were summaried and the method about the chromatography with solid phase extraction was studied in this part.In the second part, the technique of solid-phase extraction was researched. The preparation method of vegintables and fruits was studied as follows:using acetonitrile as extract solvent, OPs can be enriched by solid phase extraction with florisil and the analytes were eluted by acetonitrile.The preparation method of tea was studied as follows:using actone as extract solvent with...