中文摘要：

建立了基于分散液-液微萃取的气相色谱-质谱（GC—MS）联用对白菜汁、橙汁中11种痕量农药的富集和检测方法．实验优化了各种分散液-液微萃取的影响因素，最终选择萃取剂为20μL四氯化碳，分散剂为1．5mL乙腈．在最佳条件下各农药检出限低于0．25μg·L-1，富集因子最高为636倍．除氟硅唑和稻丰散回收率偏低外，大部分农药在白菜汁中的中、高浓度平均加标回收率在62．8％-119．7％，RSD在2．66％-15．62％（n=3）；在橙汁样品中的中、高浓度平均加标回收率在67．6％～112．8％，RSD在6．64％-15．98％（n=3）．实验结果表明，分散液-液微萃取技术具有操作简单、快捷、富集因子高、精密度高等特点，与GC—MS联用是检测蔬菜及水果汁中痕量农药残留的-种方便、高效的方法．

英文摘要：

Based on the sample preparation method of dispersive liquid- liquid microextraction （DLLME） and gas chromatography/mass spectrometry （GC -MS）, a method to determine trace a- mount of pesticide residues in the orange juice and cabbage juice was established. Several factors were optimized by DLLME experiments. Carbon tetrachloride （20 μL） was selected as extraction solvent, and acetonitrile（ 1.5 mL） was selected as dispersive solvent. Under the optimized conditions, the line- ar regression equations of the pesticide residues in the deionized water were described, and the limits of detection were below than 0.25 μg . L-1. The enrichment factors were between 231 and 636. The method was used for the pesticide residues in the orange juice （diluted） and cabbage juice（diluted）. Except for phenthoate and flusilazole, the average recoveries of pesticide residues in cabbage juice were between 62.8% ~ 119.7%, the RSDs were between 2.66% -15.62% （n =3） ; the average recoveries of pesticide residues in orange juice were between 67.6% - 112.8% , the RSDs were 6.64% - 15.98% （ n = 3 ）. The results show that DLLME method has the advantages of simple and fast operation, high accumulation rate and high degree of acccuraey. This technique combined with GC -MS would be a convenient and effective method to analyze and determine trace amount of pesti- cide residues in juices of orange and cabbage.