气相色谱-串联质谱法测定水果中50种农药残留

Determination of 50 pesticide residues in fruits by gas chromatography-tandem mass spectrometry

建立了气相色谱-串联质谱测定水果中50种农药残留的分析方法。考察了无缓冲盐体系、乙酸盐缓冲体系和柠檬酸盐缓冲体系提取水果中50种农药的有效性,并对比了乙二胺-N-丙基硅烷(PSA)吸附剂净化和SinChERSNano柱净化两种净化方法。结果表明,存在缓冲盐体系的QuEChERS方法提取效果更好且两种缓冲盐体系无明显差别,最后选择乙酸盐缓冲体系;通过比较净化效果和总离子流色谱图,发现SinChERS-Nano柱净化的效果更好。对50种农药进行加标回收试验,发现甲胺磷、乙酰甲胺磷、氧化乐果、三氯杀螨醇、百菌清这5种农药回收率为71.2~129.2%,其他45种农药的回收率为79.1~122.3%。方法的检出限(LOD)为0.3~3.0μg/kg;定量限(LOQ)为1.0~10.0μg/kg。该方法适用于柑橘、葡萄等水果中50种农药残留的快速筛查分析。

A method for the determination of 50 pesticides in fruits by gas chromatography-tandem mass spectrometry(GC-MS/MS)was developed.The three QuEChERS methods(the original one without buffer,the one with acetate buffer and the one with citrate buffer)were compared.The purification effects of primary secondary amine(PSA)and SinChERS-Nano column were also investigated.The results showed that the acetate buffer and the citrate buffer had positive influence on the extraction compared to the original method without buffer,and there was no significant difference between the two methods using buffers.Finally,the QuEChERS method using acetate buffer was chosen as the extraction method.By comparing the purification effect images and the total ion current(TIC)chromatograms,SinChERS-Nano column was revealed to have a better cleaning effect,and was chosen for cleanup.The recoveries of methamidophos,acephate,omethoate,chlorothalonil and dicofol were in ranged of 71.2%-129.2%,the other 45 pesticides were ranged from 79.1%to 122.3%.The limits of detection(LODs)were 0.3-3.0μg/kg and the limits of quantification(LOQs)were 1.0-10.0μg/kg.The method is rapid and suitable for the screening of the 50 pesticide residues in citrus,grapes and other fruit samples.