离子液体均相液液微萃取-高效液相色谱法测定婴儿奶粉中5种三嗪类除草剂

建立了婴儿配方奶粉中三嗪类除草剂的均相液液微萃取-高效液相色谱分析方法。以离子液体为液液微萃取溶剂,Eclipse XDB-C18为色谱柱,乙腈和水为流动相梯度洗脱分离。详细研究了液液微萃取条件对实验结果的影响。在最优实验条件下,三嗪类除草剂的标准曲线呈良好的线性(r≥0.9992),草净津、敌草净、特丁通、特丁津和异戊乙净的检出限分别是12.1、13.8、11.8、14.6和13.7 μg/kg;婴儿配方奶粉中的加标回收率为92.2%~103.2%,相对标准偏差低于6%。该方法灵敏度高、操作简单,适用于奶粉样品中三嗪类除草剂残留的检测。

Determination of five triazine herbicides in infant milk powder by high performance liquid chromatography coupled with ionic liquid-based homogeneous liquid-liquid microextraction

A high performance liquid chromatography coupled with homogeneous liquid-liquid microextraction was developed for the determination of five triazine herbicides in infant milk powders. The ionic liquid was used as microextraction solvent. The separation of the herbicides was performed on an Eclipse XDB-C18 column using acetonitrile and water as mobile phases in gradient mode. The effects of homogeneous liquid-liquid extraction conditions on the experimental results were investigated in detail. Under the optimized experimental conditions, the calibration curves for determining the analytes were linear and the correlation coefficients were ≥0.9992. The limits of detection for cyanazine, desmetryn, terbumeton, terbuthylazine and dimethametryn were 12.1, 13.8, 11.8, 14.6 and 13.7 μg/kg, respectively. The recoveries of the analytes spiked in four infant milk powders ranged from 92.2% to 103.2% and the relative standard deviations were lower than 6%. This method is sensitive, simple, and suitable for the determination of triazine herbicides in milk powder samples.