A novel analytical method was developed for the determination of five acetanilide herbicides (alachlor,acetochlor,metolachlor,butachlor and pretilachlor) in water and green tea samples by graphenebased magnetic solid phase extraction-dispersive liquid liquid microextraction and gas chromatography with flame ionization detection (GC-FID).Some important experimental parameters that could influence both the magnetic solid phase extraction and the dispersive liquid liquid microextraction were investigated.Under the optimum conditions,as high as 3399 to 4002 fold enrichment factors were achieved.A good linearity existed in the range of O.1-50.0 μg/L for all the five herbicides with the correlation coefficients (r) varying from 0.9973 to 0.9993.The limits of detection ranged from 0.01 to 0.03 μg/L,and the relative standard deviations were between 3.8％ and 5.8％.The method was applied to the analysis of the acetanilide herbicides in environmental water and green tea samples with satisfactory result.%采用磁性石墨烯纳米复合材料作为磁性固相萃取剂进行磁性固相萃取,再进行分散液液微萃取,采用气相色谱建立了高灵敏测定环境水样和绿茶中5种酰胺类除草剂残留的方法.对影响萃取效率的诸因素进行了优化.在优化条件下,5种酰胺类除草剂的富集倍数在3399 ～ 4002之间,甲草胺、乙草胺、异丙甲草胺、丁草胺和丙草胺浓度在0.1～50μg/L范围内与峰面积呈良好的线性关系,线性相关系数在0.9973～0.9993之间,检出限在0.01 ～0.03 μg/L范围内.本方法应用于河水、自来水和绿茶样品的分析,平均加标回收率在80.2％～108.4％之间,相对标准偏差在3.8％ ～5.8％之间.本方法操作简单、灵敏、富集倍数高.
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