蔬菜农药残留检测中基质效应影响因素分析

为了提高农药检测的准确率,试验选择气相色谱(7890A、1310)与气相串联质谱(GCMS-MS)3种不同仪器,结球白菜、结球甘蓝、黄瓜、辣椒4种蔬菜样品及其基质标准溶液和正己烷溶剂标准溶液,对4种不同蔬菜中分别添加腐霉利、甲氰菊酯、氯氰菊酯、溴氰菊酯4种农药并进行回收校正,比较不同的校正溶液、不同仪器以及不同的样品类型对蔬菜农药残留检测中的基质效应的影响。结果显示:按不同基质标准溶液和溶剂标准溶液校正的检测结果分类,不同蔬菜、不同的标准校正溶液对于农药残留检测中的基质效应表现出多样性和复杂性的特点。但采用与本底一致的基质标准溶液校正样品可有效消除基质效应。按不同仪器检测结果分类,气相色谱(7890A、1310)与气相串联质谱(GC-MS-MS)基质效应的影响存在一定的差异,GC-MS-MS存在较为明显的基质增强效应;而同类仪器(7890A、1310)之间基质效应的影响较小。

Analysis of Infl uencing Factors of Matrix Effect in Vegetable Pesticide Residues Detection

Abstract: In order to improve the accuracy of pesticide detection, gas chromatography (7890A, 1310) and gas-phase tandem mass spectrometry (GC-MS-MS) were used to determine four kinds of vegetable samples which included chinese cabbage, heading cabbage, cucumber and pepper and their matrix standard solution and n-hexane solvent standard solution. Procynidone, fenpropathrin, cypermethrin and deltamethrin were added to four kinds of vegetables respectively. Four kinds of ester pesticides were recovered and calibrated. The matrix effects of different calibration solutions, different instruments and different sample types on the detection of pesticide residues in vegetables were compared. The results showed that the matrix effects of different vegetable and standard calibration solutions for pesticide residues detection showed diversity and complexity according to the calibration results of different matrix standard solutions and solvent standard solutions. However, the matrix effect could be effectively eliminated by calibrating the sample with a matrix standard solution consistent with the background. According to the results of different instruments, there were some differences in matrix effect between gas chromatography (7890A, 1310) and gas-phase tandem mass spectrometry (GC-MS-MS). GC-MS-MS had obvious matrix enhancement effect, while similar instruments (7890A, 1310) had less matrix effect.