固相萃取-气质联用技术快速测定蔬菜多组分农药残留

Rapid determination of pesticide residues in vegetables by solid phase extraction and GC-MS

目的建立同时测定蔬菜中29种农药残留的检测方法。方法样品使用乙腈萃取,Carb/NH2固相萃取柱(SPE)除杂,丙酮定容。采用HP-5MS分析柱,程序升温分离,以选择离子监测方式(SIM)监测目标化合物的特征离子进行定性定量分析。对提取条件、固相萃取模式、选择淋洗溶剂、色谱条件、质谱采集方式等进行优化,并对实际样品进行分析。结果 29种农药残留的加标回收率范围在72.7%~106.6%,相对标准偏差(RSD)为4.4%~11.6%,检出限(LOD)范围0.001~0.020 mg/kg,定量限(LOQ)范围0.003~0.060 mg/kg。结论本方法有效消除色素等复杂基质的干扰,实现一次进样多组分同时分析,准确度和灵敏度好,可满足蔬菜中多组分农药残留的同时测定。

Objective To establish a method for simultaneous determination of 29 kinds of pesticide residues in vegetables. Methods Extracted by using acetonitrile, the samples were cleaned by Carb/NH2 solid phase extraction（SPE） and volumed with acetone. 29 kinds of pesticide residues in vegetables were separated with HP - 5MS capillary column with temperature programming. The qualitative and quantitative analysis were achieved by monitoring the characteristic ions of the target compounds with selected ion monitoring mode（S1M）. Extraction conditions, solid phase extraction mode, selec- tion of rinse solvent, separation conditions and mass spectrum acquisition were all discussed systematically, and actual sam- ples were analyzed. Results The spiked recoveries about 29 kinds of pesticide residues were in the range of 72.7% - 106.60% , the relative standard deviation （RSD） was 4.4% - 11.6% , the detection limit （LOD） ranged from 0.001 to O. 020 mg/kg, the limit of quantitation （LOQ） ranged from 0. 003 to 0. 060 mg/kg. Conclusion This method effectively eliminates interference in pigments and other complex matrices. To achieve a simultaneous analysis of multi - component in- jection, accuracy and sensitivity, and can meet the simultaneous determination of multi - component pesticide residues in vegetables.