QuEChERS-超高效液相色谱-串联质谱技术同时测定大蒜中10种农药残留

建立了快速、准确测定大蒜中10种农药多残留的QuEChERS-超高效液相色谱-串联质谱检测技术。样品经酸化乙腈提取,无水硫酸镁(500 mg)除水后,用N-丙基乙二胺(PSA,500 mg)和十八烷基键合硅胶(C₁₈,500 mg)净化,以乙腈和0.1%甲酸水溶液为流动相进行梯度洗脱,Waters C₁₈色谱柱分离,采用正离子多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。10种农药的检出限在0.020~0.800 μg·kg^-1,定量限在0.067~2.670 μg·kg^-1。线性范围内相关系数均大于0.99。加标回收率在73.4%~109.0%,相对标准偏差在1.2%~9.8%。结果表明,该方法简便、快速、灵敏度高、重现性好,可同时测定大蒜中10种农药。

Determination of 10 pesticide residues in garlic by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry

A method for rapid and accurate determination of 10 pesticide residues in garlic by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry was developed. Samples were extracted by acidified acetonitrile, dehydrated with anhydrous magnesium sulfate (500 mg) and cleaned up by primary secondary amine (PSA, 500 mg) and octadecyl bonded silica gel (C₁₈, 500 mg). The target samples were separated by Waters C₁₈ column with gradient elution using acetonitrile and 0.1% formic acid aqueous solution as mobile phases. The positive ion mode and multiple reaction monitoring (MRM) mode were used in the analysis, and the analytes were quantified by external standard method using matrix-matched calibration curves. The limits of detection of the 10 pesticides were in the range of 0.020 to 0.800 μg·kg^-1 and the limits of quantitation were in the range of 0.067 to 2.670 μg·kg^-1. The correlation coefficients in the linear range were more than 0.99. Average recoveries were from 73.4% to 109.0% and the relative standard deviations (RSD) were from 1.2% to 9.8%. The method is simple, easy, sensitive, reproducible and applicable to the simultaneous determination of 10 pesticide residues in garlic.