Research Of Pesticide Multiresidue Determination Technique In Allium Vegetables By Microwave Heating-gas Chromatography Tandem Mass Spectrometry Method

Allium vegetables are our preference seasoning vegetables, which play an important role in the annual production and supply. The national food safety standards and all levels of agricultural products quality and safety stamdards set strict safety guidelines, but due to its special properties, cause great difficulties for pesticide residue determination. This research on the basis of the existing literature and research results, use of advanced test equipment, establishment of allium vegetables pesticide residue determination method of agricultural products, to break the routine monitoring, green food and the pollution-free agricultural products certification testing problem, and provides ideas on determination techniques for risk assessment of allium vegetables.First of all, this paper reviews the pesticide residue sample collection and pretreatment techniques and determination methods, summarizes the national food safety standards and standards of green food, pollution-free agricultural products in Allium vegetables pesticide residue limits.Secondly, according to the test standard of national and industry standards, with the rapid method, gas chromatography, GC-MS in pesticide residue detection methods of Allium species were verified and compared, analyzed the existing technical problems and difficulties.Thirdly, the conditions of microwave heating, gas chromatography tandem mass spectrometry analysis conditions, extraction solvent, extraction method and sample purification conditions, established the microwave heating, acetonitrile homogenate, graphitized carbon black/amino double solid-phase extraction column purification, gas chromatography-three tandem quadrupole mass spectrometry (MRM) detection, internal standard method and48kinds of qualitative and quantitative detection in Allium vegetables pesticide multi residue analysis method. The25.0g sample is heated in a microwave oven25s, then add50.0mL were extracted by acetonitrile, extract nitrogen blown nearly dry, With25.0mL of acetonitrile and toluene (3+1) transfer, graphitized carbon black/amino double solid-phase extraction column purification, the nitrogen blowing nearly dry, after the constant volume gas chromatography tandem mass spectrometry determination of multiple reaction monitoring mode (MRM), internal standard method. To detect48kinds of pesticides in leek, onion, garlic and onion in a sample of residues with this method, each chemical can be well separated from other constituents, without significant interference; pesticides in leek addition experiments showed that48kinds of pesticides in the range of0.01mg/kg-1.0mg/kg, the linear correlation coefficient r in the range of0.9881-1.000, good linear relationship; in4kinds of Allium vegetables were added to0.01mg/kg,0.05mg/kg,0.10mg/kg three levels, the average recovery rate is between61.85%-111.53%, the recovery of pesticides more than90%of the ratio between70%-110%, the relative standard deviation is between1.7%-13.1%, the accuracy and precision of the method is better; qualitative detection limits (LOD) in the range of0.023-3.5μg/kg, the limits of quantification(LOQ) are lower than that of0.01mg/kg.The method is simple, fast, efficient, accurate, sensitive, quantitative and qualitative to apply48kinds of allium vegetables pesticide residues in. And it can meet the current national food standards, pollution-free and green food on the detection of pesticide residue in vegetable alliaceous detection limit requirements.