QuEChERS-超高效液相色谱串联质谱法测定大米中30种农药残留

QuEChERS-Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of 30 Pesticide Residues in Rice

采用QuEChERS前处理技术,结合超高效液相色谱串联质谱联用仪,建立大米中30种农药残留的测定方法。优化样品的提取溶剂、净化方式、液相色谱的分离条件和质谱参数等技术指标,采用优化后的条件,大米样品经体积分数1%乙酸乙腈提取,QuEChERS法净化后,用体积分数0.1%甲酸水(含2 mmol/L甲酸铵)和甲醇为流动相,经Eclipse Plus C18(2.1 mm×50.0 mm,1.8μm)分离,采用电喷雾电离(ESI)和多离子检测模式(MRM)进行检测,基质外标法定量。30种农药的质量浓度在0.001~0.050 mg/L内与峰响应呈线性关系,线性相关系数均大于0.995,定量限(10S/N)在0.02~2.98μg/kg,在3~30μg/kg添加浓度范围内,平均回收率在70.3%~109.8%,相对标准偏差在1.1%~11.4%。

The determination method of 30 pesticide residues in rice was established by use of QuEChERS preparation technique and combination of ultra-high-performance liquid chromatography-tandem mass spectrometry.The technical indexes,including extraction solvent,purification method,chromatographic separation conditions and mass spectrometry parameters,etc.were optimized.Under the optimized conditions,rice samples were extracted by 1%acetic acid acetonitrile,purified by QuEChERS method,and with 0.1%formic acid water(containing 2 mmol/L ammonium formate)and methanol as mobile phases.Chromatographic separation was achieved by use of Eclipse Plus C18(2.1 mm×50.0 mm,1.8μm).Detection was performed by use of electrospray ionization(ESI)and multiple reaction monitoring(MRM)mode,and matrix-matched calibration was used for quantification.The calibration curves of the 30 pesticides indicated good linearity over the concentration range of 0.001-0.050 mg/L,with correlation coefficients greater than 0.995.The limits of quantification(LOQs)were between 1μg/kg and 10μg/kg,and the recoveries ranged from 70.3%to 109.8%with relative standard deviations(n=6)of 1.1%~11.4%in the range of 3-30μg/kg.