气相色谱-飞行时间质谱联用快速筛查桃中的25种农药残留

Rapid Screening of 25 Pesticide Residues in Peach by Gas Chromatography-time of Flight Mass Spectrometry

应用分散固相萃取（DSPE）与分散液液微萃取（DLLME）相结合的样品前处理技术,与气相色谱-飞行时间质谱（GC-TOF/MS）联用,建立了同时快速筛查桃中25种农药残留的分析方法,实验考察了2种萃取方法中影响净化和萃取效率的各个因素,并建立了飞行时间质谱农药筛查数据库。结果表明：在优化的实验条件下,25种农药在一定的浓度范围内线性良好,相关系数（r）均大于0.98;桃空白基质在10、30、50μg/kg 3个不同的添加浓度下,农药的平均回收率为64.9%~119.8%,相对标准偏差（RSD）为3.5%~22.1%,方法的检出限（LOD,S/N≥3）和定量限（LOQ,S/N≥10）范围分别为0.01~12.30μg/kg和0.1~36.7μg/kg。

In the article, a simple and efficient method for rapidly screening of 25 pesticide residues simultaneously in peach was developed by using dispersive solid phase extraction（DSPE）and dispersive liquid-liquid microextraction（DLLME） coupled with gas chromatography-time of flight（GC-TOF/MS）. Parameters affecting purification and extraction efficiency in both procedures were investigated and optimized to achieve the best extraction efficiency. Database of GC-TOF-MS for the screening of pesticides was also established. In the optimum conditions, the results showed that all the 25 pesticides had good linearity in a certain range and the correlation coefficient（r） was higher than 0.98. The average recoveries for the most of the pesticides in peach matrices were in the range of 64.9%-119.8% at three spiked levels of 10 μg/kg, 30 μg/kg, 50 μg/kg, with RSDs of 3.2%-22.1%. The limits of detection（LOD, S/N≥3）and LOQ（S/N≥10） of the method were 0.01-12.30 μg/kg and 0.1-36.7 μg/kg respectively.