The Study On The Analytical Methods Of Pesticide Multiresidues In Foodstuff

This thesis consists of two chapters.In CHAPTER ONE, literature review. Summarized actuality and progress on analyticaltechnologies of pesticide residues in food. Firstly, introduced the actuality and progress oftechnologies for sample pretreatment in detail. Secondly, summarized the existingtechnologies for determing pesticide residues. Finally, showed some examples to introducehow to analyze pesticide residues in common food.In CHAPTER TWO, used corn and rice as samples to study the analytical methods ofpesticide multiresidues in foodstuff. A new analytical method has been developed todetermine pesticide multiresidues in foodstuff using gas chromatography mass spectrometry,including organophosphorus, organochlorine, carbamate and pyrethroid.This method is based on an extraction of pesticides with solvents and a further clean-upprocedure by solid-phase extraction (SPE). Dichloromethane was selected as the solvent usedin extraction by the results of experiment; Florisil was selected as the SPE sorbent. Then theeluent and the conditions of clean-up were confirmed.The parameters of Gas chromatography and Mass spectrometry were confirmed.Selected-ion monitoring (SIM) was performed. All pesticides were identified by retentiontime and the proportion of selection ions, and quantified by extra-standard. Then, the resultsof accuracy, precision, linearity and the limits of detection (LOD) was shown that the methodwas validated.This method can analyzed nearly 40 kinds of pesticide residues simultaneity, and hashigh accuracy, good precision and linearity, The LOD of this method is lower than MRLswhich was regulated by Europe Union (EU) and Codex Alimentarius Commission (CAC).