QuEChERS-气相色谱-串联质谱法测定大米中的敌草索残留量

Determination of Chlorthal Dimethyl Residue in Rice by QuEChERS-GC-MS

建立了一种QuEChERS-气相色谱-串联质谱法检测大米中敌草索残留量的测定方法。样品采用酸化乙腈进行提取,利用QuEChERS方法净化提取液,除去色素、脂类、内源性杂质,浓缩后用气质联用法进行定量分析和定性确认。结果表明,敌草索的分离度和峰形较好,在0.02~1.00μg·mL^(-1)线性关系良好,相关系数(R2)为0.9993;方法的精密度为3.4%~8.9%,回收率为83.1%~108.8%,检测限为0.001 mg·kg^(-1),质谱定性和定量准确,可用于大米中敌草索残留量的检测。

An analytical method for the determination of chlorthal dimethyl in rice by QuEChERS-GC-MS was established.The sample was extracted with acidified acetonitrile,and the extract was purified by QuEChERS method to remove pigment,lipid and endogenous impurities.After concentration,quantitative analysis and qualitative confirmation were carried out by GC-MS.The results showed that the separation degree and peak shape were good,the linear relationship between 0.02μg·mL^(-1) and 1.00μg·mL^(-1) was good,and the correlation coefficient(R2)is 0.9993;The precision of the method is 3.4%~8.9%,the recovery rate is 83.1%~108.8%,and the detection limit is 0.001 mg·kg^(-1).Mass spectrometry is accurate in qualitative and quantitative analysis,and can be used for the determination of chlorthal dimethyl residues in rice.