微波辅助提取-分散固相萃取-高效液相色谱-串联质谱法测定果蔬中20种农药的残留

Determination of 20 kinds of pesticides residues in fruits and vegetables by microwave–assisted extraction-dispersive solid-phase extraction-high performance liquid chromatography-tandem mass spectrometry

中文关键词:  农药残留  高效液相色谱-串联质谱法  微波辅助提取  分散固相萃取  杀虫剂  杀菌剂

英文关键词:pesticide residue  high performance liquid chromatography-tandem mass spectrometry  microwave-assisted extraction  dispersive solid-phase extraction  insecticides  bactericides

中文摘要:

      目的 建立微波辅助提取-分散固相萃取-高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry, HPLC-MS/MS)测定果蔬中20种杀虫剂、杀菌剂类农药残留量的方法。方法 样品用乙腈萃取, 微波辅助提取后,经分散固相萃取净化, 采用Waters Atlantis T3(3 μm, 150 mm×2.1 mm)色谱柱分离, 以0.1%甲酸水(A)和0.1%甲酸-乙腈(B)进行梯度洗脱,采用多反应监测(multi-reaction monitoring, MRM)正离子模式进行检测, 以基质校准曲线外标法定量。结果 20种农药在0.5~50 μg/L质量浓度范围内线性良好, 相关系数(r2)均大于0.99。方法的检出限(limits of detection, LODs) (S/N=3)和定量限(limits of quantification, LOQs) (S/N=10)分别为0.2~4.9 μg/kg和0.7~15.0 μg/kg。同时考察了苹果、西红柿、大白菜、马铃薯四种基质中定量限、20和50 μg/kg 3个添加水平的回收率, 均在64.5%~121.0%之间, 相对标准偏差在1.1%~7.2%之间(n=6)。结论 该方法采用微波辅助提取与分散固相萃取相结合, 具有前处理简单、灵敏度高等特点,适合果蔬中20种杀虫剂及杀菌剂类农药残留的检测。

英文摘要:

      Objective To establish a method for determination of 20 kinds of insecticides and bactericides residues in fruits and vegetables by microwave–assisted extraction-dispersive solid-phase extraction coupled with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS). Methods The samples were extracted with acetonitrile, microwave–assisted extraction, and purified by dispersive solid-phase extraction, then were separated on Waters Atlantis T3 column (3 μm, 150 mm×2.1 mm) and eluted with acetonitrile(0.1% formic acid)-water(0.1% formic acid) gradient. The pesticides were detected under the multi-reaction monitoring (MRM) positive ion mode, and the corresponding quantification was performed by employing the method of external standards with matrix calibration curve. Results Under the optimized experimental conditions, the 20 kinds of pesticides were linear in the mass concentration range of 0.5?50 μg/L, and the correlation coefficients(r2) were all greater than 0.99, The limits of detection (LODs) (S/N=3) and limits of quantification (LOQs) (S/N=10) were found to be in the ranges of (0.2?4.9) μg/kg and (0.7?15.0) μg/kg, respectively. Furthermore, the average recoveries of 20 pesticides ranged from 64.5% to 121.0% at three spiked levels of LOQs, 20 and 50 μg/kg in four matrices of apple, tomato, cabbage, potato with a relative standard deviation (RSD) range of 1.1%?7.2% (n=6). Conclusion This method combined with microwave assisted extraction and dispersive solid-phase extraction has the advantages of simple pretreatment, complete purification and high sensitivity, which is suitable for the determination of 20 kinds of insecticides and bactericides in fruits and vegetables.