不同基质效应对蔬菜中有机磷农药残留检测的影响

Influence of different matrix effects on determination of organophosphorus pesticide residues in vegetables

目的探讨不同蔬菜基质对有机磷农药测定的影响以及不同有机磷农药在不同质量浓度水平下产生的基质效应。方法以茄子、豇豆、番茄、黄瓜4种蔬菜为试样,采用气相色谱-火焰光度检测器检测并对峰面积响应值进行比较,分析4种蔬菜基质对8种有机磷农药在0.05、0.1、1.0 mg/L 3个质量浓度水平下产生的基质效应。结果 4种蔬菜对8种有机磷农药的测定均存在不同程度的基质增强或基质减弱效应,其基质效应为0.755~2.442。基质效应的强弱与有机磷农药及蔬菜的种类有关,与有机磷农药的浓度没有明显的关联性。结论在蔬菜有机磷农药残留检测中,建议采用基质配制的标准品进行定量检测,从而保证检测结果的准确性。

Objective To explore the effects of different vegetable matrices on the determination of organophosphorus pesticides and the matrix effects of different organophosphorus pesticides at different concentration levels. Methods The pesticides in 4 kinds of vegetables including eggplant, cowpea, tomato and cucumber were detected by gas chromatography-flame photometric detector （GC-FPD） and the response values of peak area were compared. The matrix effects produced by the 4 kinds of vegetable matrices on the determination of 8 kinds of organophosphorus pesticides at concentrations of 0.05, 0.1, 1.0 mg/L were analyzed. Results Matrix effects of enhancement or inhibition to different contents were produced by the 4 vegetable samples. The matrix effects were 0.755-2.442. Magnitude of the matrix effect was found to be related to the kinds of organophosphorus pesticides and the kinds of vegetable samples, but not to the concentrations of the pesticides. Conclusion It is recommendable to apply the matrix-matched external standard method on the determination of organophosphorus pesticides in real samples, so as to ensure the accuracy of the detection results.