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 chromato-graphic 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.%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％.
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