固相萃取-在线凝胶渗透色谱-气相色谱/质谱法测定板栗中44种有机磷农药残留

Determination of 44 Organophosphorous Pesticides Residual in Chestnut Using Solid Phase Extraction and On-line Gel Permeation Chromatography/Gas Chromatography-Mass Spectrometry

建立了板栗中44种有机磷农药多残留的分析方法。样品以V(乙腈)∶V((水)=4∶1为提取剂,经高速匀浆方法提取,提取液以ENVI-18固相萃取柱净化,除去样品中大部分的脂肪和甾醇等干扰基质,再经在线凝胶渗透色谱-气相色谱/质谱(GPC-GC/MS)分析,进一步除去样液中色素和脂肪等大分子干扰物质,有效地降低了样品中的复杂基质所带来的背景干扰。加标水平为0.05 mg/kg时,大部分农药的回收率为65%～120%,相对标准偏差小于15%;44种农药的检出限为0.002～0.05 mg/kg。采用外标法定量,气相色谱-质谱法(GC-MS)定性定量分析,线性关系和回收率结果均满意。实验证明,本方法是一种快速、准确、灵敏度高的同时检测板栗中有机磷农药多残留的检测方法。

An analytical method has been developed for the determination of 44 organophosphorous pesticides in chestnut. With acetonitrile-water（4： 1, V/V） as the extraction solution, the samples were extracted by means of high-speed homogenization. And the crude extract was purified by ENVI-18 solid phase extraction column to remove most fats and sterols in samples, then after on-line GPC-GC/MS analysis which further removed macromolecular interference material, such as pigment and fat, the backgroud interference brought about by the complex matrix in samples was effectively reduced. When standard addition to the samples was 0.05 mg/kg, the recovery rate for most of pesticides was from 65% to 120% , and the relative standard deviation was less then 15%. The limits of detection of 28 organophosphorous pesticides were 0. 002 - 0.05 mg/kg. With the application of external standard and gas chromatography-mass spectrometry, the linear relations and the recovery results were satisfactory. Experiments showed that the method is rapid, accurate and highly senstive, and can be used for the simultaneous detemination of organophosphorous pesticides residues in chestnut.