Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China.
Anal Chim Acta. 2011 Sep 2;701(1):86-91. doi: 10.1016/j.aca.2011.04.058. Epub 2011 Jun 17.
In this work, a simple, practical and environmentally friendly sample pre-treatment method, ultrasound-assisted surfactant-enhanced emulsification microextraction coupled with high performance liquid chromatography-diode array detector/electrospray ionisation mass spectrometry, was developed to determine diethofencarb and pyrimethanil residues in water and fruit juice samples. Tween 80 was used as an emulsifier and carbon tetrachloride was chosen as the extraction solvent, and no dispersive organic solvent was needed, which is typically required in common dispersive liquid-liquid microextraction methods. Several variables, such as the type and volume of extraction solvent and surfactant, extraction temperature and ultrasound extraction time were investigated and optimised. Under optimal conditions, the enrichment factors were 265 and 253 for diethofencarb and pyrimethanil, respectively. The limits of detection (LODs), calculated as three times the signal-to-noise ratio (S/N), were 0.01 μg L(-1) for both diethofencarb and pyrimethanil. The linearity of the method was obtained in the range of 0.05-2000 μg L(-1), with correlation coefficients of 0.9994-0.9998. The water (at fortified levels of 0.1 and 1.0 μg L(-1)) and fruit juice samples (at fortified levels of 0.1 and 1.0 μg L(-1)) were successfully analysed using the proposed method, and the relative recoveries were in the range of 88-114%, 93-111%, 86-117% and 94-101%, respectively.
在这项工作中，开发了一种简单、实用且环保的样品预处理方法，即超声辅助表面活性剂增强乳化微萃取结合高效液相色谱-二极管阵列检测器/电喷雾离子化质谱法，用于测定水样和果汁中的二噻农和嘧啶胺残留。吐温 80 用作乳化剂，四氯化碳选为萃取溶剂，无需分散有机溶剂，这是常见的分散液液微萃取方法中通常需要的。考察并优化了几种变量，如萃取溶剂和表面活性剂的类型和体积、萃取温度和超声萃取时间。在最佳条件下，二噻农和嘧啶胺的富集因子分别为 265 和 253。检测限（LOD），按三倍信噪比（S/N）计算，均为 0.01 μg L(-1)。该方法在 0.05-2000 μg L(-1)范围内具有线性关系，相关系数为 0.9994-0.9998。采用所提出的方法成功分析了水样（在 0.1 和 1.0 μg L(-1)加标水平）和果汁样品（在 0.1 和 1.0 μg L(-1)加标水平），相对回收率在 88-114%、93-111%、86-117%和 94-101%之间。
