介孔氧化铝净化-气相色谱法同时测定蔬菜、水果及茶叶中16种有机磷农药残留

摘要

A gas chromatographic method based on solid-phase extraction was developed for the simultaneous determination of 16 organophosphorous pesticides in vegetables,fruits and tea,including cabbage,lettuce,pumpkin,onion,tomato,turnip,apple,pear and tea. The samples were extracted with ethyl acetate,and clean-up with mesoporous alumina as solid-phase extraction adsorbent. The separation of target compounds was performed on a DB-1701 capillary column,and the quantitative analysis of the organophosphorous pesticides was carried out by gas chromatography with flame photometric detection. The results showed that the cali-bration curves of the 16 organophosphorous pesticides were linear in the range of 10-2 000μg/L with good correlation coefficients(R2﹥0. 997). The recoveries of the pesticides in differ-ent samples at three spiked levels ranged from 83. 2% to 103. 8% with the relative standard devi-ations of 2. 0%-9. 9%. This method has high sensitivity,high accuracy and good repeatability, and can be applied to the determination of the organophosphorus pesticide residues in vegeta-bles,fruits and tea.%利用气相色谱检测技术，建立了能应用于白菜、生菜、南瓜、洋葱、番茄、白萝卜、苹果、梨及茶叶等不同基质中16种有机磷农药残留的检测方法。样品采用乙酸乙酯提取，经以合成的介孔氧化铝作吸附剂的固相萃取柱净化， DB-1701毛细管柱分离，气相色谱-火焰光度检测器检测。结果表明，蔬菜、水果及茶叶基质中16种有机磷农药在10~2000μg/L范围内具有良好的线性关系（ R2﹥0.997）；平均回收率为83.2％~103.8％，相对标准偏差为2.0％~9.9％。该方法灵敏度高、准确度高、重复性好，可适用于蔬菜、水果及茶叶基质中16种有机磷残留量的同时测定。