QuEChERS前处理方法联合GPC-GC/MS在测定蔬菜水果农药残留中的应用

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0.01mg/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%。

Application of QuEChERS Method Coupled with Online GPC-GC/MS for Determination Pesticide Residues in Vegetables and Fruits

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.