【摘要】 采用QuEChERS前处理方法和在线凝胶过滤色谱-气相色谱-质谱(GPC-GC/MS)联用法对蔬菜水果样品中的25种有机氯、菊酯和杀螨剂等农药残留进行测定。首先用QuEChERS方法进行样品前处理,即乙腈提取,提取溶液经脱水后离心,用分散性吸附剂去除离心提取液中的干扰基质(如脂肪酸和色素等),然后直接进行在线GPC-GC/MS分析。GPC-GC/MS系统中的GPC能弥补QuEChERS方法去除干扰物质不彻底的问题,从而降低了分析背景,改善了峰形,提高了分析结果的准确性和相关质谱图的匹配性。在加标0.01 mg/kg情况下,3种样品(菠菜、黄瓜和苹果)的回收率均在80%~120%之间,相对标准偏差(RSD)均小于20%。更多还原

【Abstract】 25 pesticide residues including organochlorine,pyrethroid,acaricide in vegetables and fruits were determined by online GPC-GC/MS coupled with QuEChERS method.The results show that GPC of online GPC-GC/MS system can effectively remove chromatographic interferences that QuEChERS pretreating method can not effectively removed.Compared with GC/MS,online GPC-GC/MS has the lower interfered background and better peak shape.Identification and quantization of pesticide residues with online GPC-GC/MS can be well performed.All pesticides including three spiked samples(spinach,cucumber and apple) at the level of 0.01 mg/kg have 80%—120% of the recovery and less than 20% of the coefficients of variation.更多还原