QuEChERS-超高效液相色谱-串联质谱法测定桑叶中64种农药残留

Determination of 64 kinds of pesticide residues in mulberry leaves by QuEChERS combined with ultra performance liquid chromatography-tandem mass spectrometry

目的建立Qu ECh ERS结合超高效液相色谱-串联质谱法测定桑叶中64种农药残留的方法。方法样品经乙腈提取,应用Qu ECh ERS方法进行净化处理。使用Cortecs T3 (2.1 mm×100 mm, 2.7μm)色谱柱,用含0.1%(V/V)甲酸溶液(A)和甲醇(B)为流动相进行梯度洗脱,采用电喷雾电离(electrospray ionization,ESI)和多离子检测模式(multiple reaction monitoring, MRM)进行检测,基质外标法定量。结果 64种农药在0.001~0.050 mg/L范围内线性良好,线性相关系数均大于0.999。在1~10μg/kg添加浓度范围内,回收率为78.0%~94.9%,相对标准偏差为1.1%~5.5%。结论该方法操作简单,灵敏度高,可用于桑叶中农药残留的高通量筛查。

Objective To establish a method for the determination of 64 kinds of pesticide residues in mulberry leaves by QuEChERS combined with ultra performance liquid chromatography-tandem mass spectrometry. Methods The samples were extracted with acetonitrile, then purified by QuEChERS. The chromatographic separation was achieved by Cortecs T3(2.1 mm×100 mm, 2.7 μm) column combined with the gradient elution of 0.1%(V/V) formic acid aqueous solution(A) and methanol(B). The sample was detected by electrospray ionization(ESI) using multiple reaction monitoring(MRM), and quantified by Matrix external standard method. Results All the 64 kinds of pesticides had good linearity in the ranges of 0.001-0.050 mg/L and the correlation coefficient was greater than 0.999. The recoveries were 78.0%-94.9% and the relative standard deviations were 1.1%-5.5% in the range of 1-10 g/kg. Conclusion This method is simple and sensitive, which can be suitable used for rapid screening of pesticide residue in mulberry leaves.