QuEchERS-超高效液相色谱-串联质谱法测定草莓中8种常见农药残留

Determination of 8 pesticide residues in strawberry by QuEchERS combined with ultra-high performance liquid chromatography-tandem mass spectrometry

目的 建立一种采用QuEchERS结合超高效液相色谱-串联质谱法检测草莓中多菌灵、吡虫啉、咪鲜胺、啶虫脒、戊唑醇、苯醚甲环唑、吡唑醚菌酯和嘧霉胺等8种常见农药残留的分析方法。方法 试样用乙腈提取后,经净化材料PSA+MgSO4净化,在ACQUITY UPLC?HSS T3色谱柱上,以乙腈-5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,采用电喷雾正离子模式下多反应动态监测模式(DMRM)进行测定,基质匹配标准溶液外标法定量。结果 结果表明,在最佳实验条件下,8种农药在0.5μg/L~200μg/L浓度内呈现良好的线性关系,线性相关系数(r)>0.995,方法检出限为0.10μg/kg~0.30μg/kg。低(5μg/kg)、中(10μg/kg)、高(100μg/kg)3个添加水平下,8种农药的平均回收率为82.8%~108%,相对标准偏差为0.37%~6.9%。结论 此方法操作简便,准确可靠,灵敏度和精密度均能满足农药残留检测技术的要求,适用于草莓中农药残留的常规检测。

Objective A method for the determination of eight common pesticide residues in strawberries, including carbendazim, imidacloprid, imidacloprid, acetamiprid, tebuconazole, difenoconazole, pyraclostrobin and pyrimethanil, was established using QuEchERS combined with ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC/MS-MS). Methods The samples were extracted with acetonitrile, then cleaned up by the purification material PSA+MgSO4, and eluted on an ACQUITY UPLC? HSS T3 column with a gradient of acetonitrile-5 mmol/L ammonium acetate aqueous solution as the mobile phase. The determination was performed by multiple reaction dynamic monitoring mode(DMRM) in electrospray positive ionization mode, and quantified by external standard method using matrix-matched standard solutions. Results The results showed that the eight pesticides showed good linearity in the concentration range of 0.5 μg/L-200 μg/L under the optimal experimental conditions, with the linear correlation coefficients(r) greater than 0.995 and the method detection limits of 0.10 μg/kg-0.30 μg/kg. The mean recoveries of the eight pesticides at the three spiked levels at low(5 μg/kg), medium(10 μg/kg) and high(100 μg/kg) ranged from 82.8% to 108%, with the relative standard deviations(RSD) of 0.37%-6.9%. Conclusion The method is simple, accurate and reliable, its sensitivity and precision can meet the requirements of pesticide residue detection technology, and it is suitable for daily regulatory testing of pesticide residues in strawberries.