加速溶剂萃取-气相色谱-串联质谱法同时测定贝类中64种农药残留

建立了加速溶剂同步萃取净化-气相色谱-串联质谱(GC-MS/MS)同时测定贝类中64种农药残留的方法。加速溶剂萃取的萃取溶剂为90%(v/v)乙腈水溶液,萃取温度为85℃、冲洗体积60%萃取池体积、循环次数1次,同时使用0.8 g N-丙基乙二胺(PSA)和0.8 g石墨化炭黑(GCB)在线净化,提取液浓缩定容后,在多反应监测(MRM)模式下测定,外标法定量。结果表明,64种农药在10.0～1 000μg/L范围内呈现良好的线性关系,决定系数(r²)均大于0.989,方法的定量限为2.0～10.0μg/kg;对文蛤空白基质进行加标回收试验,添加水平为5.0、10.0和100μg/kg以及定量限水平,得到的平均回收率为69.4%～129.7%,精密度为0.7%～16.0%(n=6)。该方法提取和净化同步完成,操作简单,重复性好,灵敏度高,能够满足于贝类水产品中多种农药残留的同时筛查。

Simultaneous determination of 64 pesticide residues in shellfish by accelerated solvent extraction coupled with gas chromatography-tandem mass spectrometry

A method was established for the determination of 64 pesticide residues in shellfish using accelerated solvent simultaneous extraction and purification coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). The target compounds were extracted from shellfish using 90% (v/v) acetonitrile aqueous solution with 60% of the pool volume at 85℃ via a single cycle of accelerated solvent extraction. The extracts were synchronously purified with primary secondary amine (PSA) and graphitized carbon black (GCB) added to the extracting cell. After concentration, the target compounds were detected by GC-MS/MS in the multiple reaction monitoring (MRM) mode, and quantified by using the external standard method. Under the optimized conditions, good linearities were obtained for the 64 pesticides in the range of 10.0-1000 μg/L, with coefficients of determination greater than 0.989. The limits of quantification for the method were between 2.0 μg/kg and 10.0 μg/kg. At four spiked levels (5.0, 10.0, 100 μg/kg, and the LOQ level) in clam, the recoveries of all the pesticides were between 69.4% and 129.7%, with the relative standard deviations varying from 0.7% to 16.0% (n=6). The method is simple, repeatable and sensitive, and it is suitable for the screening of various pesticide residues in shellfish products.