气相色谱法测定蔬菜中有机磷类农药的基质效应分析

Matrix effects analysis in the detection of organophosphorate pesticides in vegetables by gas chromatography

采用气相色谱法分析了4种蔬菜基质效应对7类有机磷农药残留检测的影响。结果表明,空白基质稀释后的农药标样回收率均在70%～120%的标准范围内。生菜、番茄、茄子、黄瓜中基质效应最强的农药分别为氧乐果(1.33)、久效磷(1.93)、氧乐果(2.19)、氧乐果(2.73),基质效应最弱的农药分别为对硫磷(1.01)、三唑磷(1.18)、三唑磷(1.02)、敌敌畏(1.25)。研究结果还表明,基质效应与农药结构和蔬菜类型有关,在单个样品检测时可采用基质校准法,日常检测时可采用通用基质法。本研究的结果为日常检测提供了依据,并为提高检测结果的准确性积累资料。

This research studied the matrix effects of four vegetables on the detection of seven organophosphorate pesticide residues by gas chromatography.The results showed that the recoveries of pesticides which were diluted by blank matrix were within the standard range of 70%-120%.In lettuce,tomato,eggplant and cucumber,the strongest matrix effects among seven pesticides are omethoate（1.33）,moncrotophos（1.93）,omethoate（2.19）,omethoate（2.73）,the weakest matrix effects among seven pesticides are parathion（1.01）,phentriazophos（1.18）,phentriazophos（1.02）,dichlorvos（1.25）,respectively.The results also showed that matrix effects are affected by the structure of pesticide and the type of vegetable.Matrix calibration can be used in single sample test and universal matrix can be used in routine analysis.The results provided the basis for daily testing and accumulated the data for enhancing the accuracy of testing results.