高效液相色谱-荧光法测定水中甲氨基阿维菌素苯甲酸盐

DETERMINATION OF EMAMECTIN BENZOATE RESIDUES IN WATER BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY WITH FLUORESCENCE DETECTION

建立了水样中甲氨基阿维菌素苯甲酸盐(甲维盐)残留量的柱前衍生高效液相色谱测定方法.水样经乙酸乙酯提取后,运用N-甲基咪唑-乙腈(NMIM-CAN)(1+1)、三氟乙酸酐-乙腈(TFAA-CAN)(1+1)在避光条件下进行柱前衍生化反应,反应20min后,用高效液相色谱-荧光检测器进行测定.结果表明,水中甲维盐添加浓度在0.0001—0.01mg.l-1范围,方法的回收率为78.4%—115.2%,变异系数为3.0%—11.3%,方法的最低定量限为0.0036mg.l-1,方法的灵敏度、精密度和准确度完全满足农药残留分析的要求.甲维盐在巢湖水中的残留量低于该方法的检出限,稻田水中的残留量为0.54mg.l-1.

The residue analysis method for determination of emamectin benzoate in water with HPLC-FLD after pre-column derivatization was developed.Emamectin benzoate was extracted with ethyl acetate,and the extract was derivatized with NMIM-CAN（1＋1）and TFAA-CAN（1＋1）for 20 minutes under the dark.The derivative was detected by HPLC.The results showed that,the recoveries of emamectin benzoate was 78.4%—115.2% and the method coefficient of variation was 3.0%—11.3%,for spiked water samples at the concentration of 0.0001—0.01mg·l-1 emamectin benzoate.The limit of quantification（LOQ）was 0.0036mg·l-1.The residue of emamectin benzoate in the water of Chaohu lake was below the detection limit of this method,while in the water of paddy field was 0.54mg·l-1.