固相萃取——气相色谱——质谱法同时测定甜瓜中11种有机磷农药残留量

Simultaneous determination of 11 organophosphorus pesticide residues in muskmelon by GC-MS with solid-phase extraction

为了建立固相萃取(SPE)气相色谱-质谱法(GC-MS),同时测定甜瓜中11种有机磷农药含量的分析方法,甜瓜样品采用乙腈提取,经Cleanert PC/NH2固相萃取小柱净化,GC-MS分析,选择离子监测模式,外标法定量.结果表明,11种有机磷农药在质量浓度0.05~2.00 mg·L^-1线性关系良好(r2>0.99),定量限在0.01~0.20 mg·kg^-1之间.3个添加水平下,11种有机磷农药的平均回收率为82.2%~103.4%,相对标准偏差(RSD)为1.1%~11.2%.该方法前处理简便,准确度、精密度和灵敏性都符合农药多残留检测的要求,结果令人满意.

To establish a method for the determination of 11 organophosphorus pesticide residues in muskmelon using solid-phase extraction(SPE) and gas chromatography- mass spectrometry(GC-MS). The pesticides were extracted with acetonitrile,and cleaned up on a Cleanert PC/NH2 SPE column,The analytes were determined by GC-MS, selective ion monitoring (SIM) model, external standard method were used for the quantification. The results showed that the linearity range of the method between 0.05-2.00 mg·L^-1 was satisfying and the limit of quantitation ( LOQ) of all pesticides were 0.01-0.20 mg·kg^-1.The results of the spiked level test showed that the average recovery of 11 organophosphorus pesticides ranged from 82.2%-103.4% with relative standard deviations(RSDs) of 1.1%-11.2% at the 3 spike levels. The pretreatment of the method was simple, the accruracy, precision and sensitivity of the method can meet the requirements of the multiple pesticide residue analysis, and the result was satisfactory.