固相萃取——气相色谱法测定蔬菜中多种有机磷农药的残留量

建立了固相萃取气相色谱法测定蔬菜中多种有机磷农药残留量的方法.蔬菜样品采用乙腈提取,氯化钠盐析分层,取部分提取液使用氮气吹干,以丙酮溶解,固相萃取柱进行净化,最后用气相色谱法进行定量分析,外标法定量.3个添加水平的12种有机磷农药平均回收率(n=5)为75.1%-105.0%,相对标准偏差为1.67%-7.50%.此方法具有快速、简便、准确、灵敏、重现性好的特点,适合蔬菜中有机磷农药残留量的测定.

Determination of Organophosphorous Pesticide Residues in Vegetable by Solid-Phase Extraction-Gas Chromatography

A method for the determination of 12 organophosphorous pesticides residues in the vegetable by solid phase extraction(SPE) coupled with gas chromatography(GC) was developed and validated.The samples were extracted by acetonitrile and salted out with sodium chloride.Some eluate was blown to dryness under a stream of nitrogen(N2) and the residue was dissolved in 2ml of acetone,followed by purification using a Carbon-NH2 SPE column.A little sample solution was then injected into the GC system to quantitative analysis.The average recoveries ranged from 75.1% to 105.0% with the relative standard deviation(RSD) range of 1.67%-7.50% for the vegetables.It is concluded that this method is rapid,accurate,sensitive and reproducible for determining trace pesticides in vegetable samples.