液相色谱荧光法测定稻谷及秸秆中阿维菌素残留量

Determination of Avermectin Residue in Rice Grain and Straw with the Method of HPLC Fluorecence Detection

[目的]运用柱前衍生-高效液相色谱荧光法,建立稻米及水稻秸秆中阿维菌素残留量的测定方法。[方法]稻米样品采用乙腈-乙酸乙酯(1∶1,V∶V)提取,水稻秸秆采用乙酸乙酯提取。提取液经三氟乙酸酐和N-甲基咪唑衍生化后,高效液相色谱荧光法测定。[结果]结果表明,在0.001～0.100mg/kg的添加浓度范围内,阿维菌素在稻米中的添加回收率为80.1%～94.5%,变异系数为3.5%～6.2%;在水稻秸秆中的回收率为77.8%～82.8%,变异系数为1.1%～4.9%。该方法在稻谷中的最小检测浓度为1.000μg/kg,在秸秆中的最小检测浓度为0.500μg/kg。[结论]该方法的灵敏度与准确度符合农药残留分析要求。

[ Objective } The method of avermeetin residue in rice grain and straw was developed through the operation of HPLC fluorecence detection. [ Method ] The rice grain samples were extracted with aeetonitrile/ethyl acetate（ 1：1 , V：V） and the riee straw samples were extracted with ethyl acetate. After derived by TFAA-NMIM system without water, the eontent of avermectin in the extraets was determined with HPLCfluoresoence detector. [ Results] The results suggested that in the range of adding concentration of 0. 001 -0. 100 mg/kg, the recovery of avermeetin from riee grain was 80. 1% -94.5% ,with the variation eoefficient of 3.5% -6.2% and riee straw, 77.8% -82.8%, with the variation eoeffieient of 1.1% -4.9%. The minimum testing eoneentration with the method for rice grain was 1. 000 μg/kg and for rice straw, 0. 500 μg/kg. [ Conclusion] The sensitivity aud accuracy of the proposed method were fitted for the analysis of pesticide residue in riee.