建立了基于离子液体涡旋辅助/表面活性剂乳化-液相微萃取高效液相色谱测定牛奶中的三嗪类和苯基脲类除草剂残留分析方法。将1-己基-3-甲基咪唑六氟磷酸盐离子液体作为提取剂，离子液体在涡旋辅助作用下分散于牛奶溶液中，同时应用表面活性剂作为乳化剂，加速分析物从水相到离子液体的传质速率，防止离心时离子液体附着于管壁。使用醋酸和硫酸钠去除牛奶中的脂肪和蛋白质，减少对分析物的提取干扰。同时考查了离子液体的种类和体积，表面活性剂的种类和体积，涡旋提取时间，离子对浓度和样品pH值对萃取效率的影响。在优化实验条件下，1~400 μg/L范围内线性良好，相关系数为0.9963~0.9998；最小检出限和定量限以最小提取浓度的3倍和10倍信噪比计算分别为0.018~0.095 μg/L和0.10~0.38 μg/L。使用该方法进行了低脂牛奶、高压消毒牛奶、纯牛奶和鲜牛奶中6种分析物的检测，同时进行3个不同浓度的添加回收实验，回收率为70.34~100.02%，RSD为2.06~9.95%。

An ionic liquid vortex-assisted surfactant enhanced emulsification microextraction (IL-VASEME) procedure was developed and validated to determine the levels of triazine and phenylurea herbicides in milk using high-performance liquid chromatography (HPLC). 1-Hexyl-3-methylimidazolium hexafluorophosphate (C6MIMPF6) was used as the extraction solvent and was dispersed in the milk solution samples with a vortex. Meanwhile, a surfactant, used as the emulsifier, enhanced the speed of the mass-transfer of analytes from the aqueous phase to the IL and prevented the IL from sticking to the centrifuge tube wall. Acetic acid and Na2SO4 were used to remove proteins and fats, thus eliminating the interference with the analytes. Additionally, the effects of the type and volume of IL, type and concentration of the surfactant, vortex extraction and centrifugation time, ion pair concentration, and sample pH on the extraction efficiency were investigated. Under the optimal conditions, a good linearity was found in the range of 1–400 μg/L, and the correlation coefficients ranged from 0.9963 to 0.9998. The limit of detections (LODs) (0.018–0.095 μg/L) and limit of quantifications (LOQs) (0.10–0.38 μg/L) of the method were calculated based on the signal-to-noise ratios of three and ten of the lowest extractable concentration, respectively. The proposed method was used to determine six herbicides in low fat milk, pasteurized plain milk, pure milk, and fresh milk, and the recovery experiments were performed at three concentration levels, while the recoveries and relative standard deviations (RSDs) ranged from 70.34% to 100.02% and from 2.06% to 9.95%, respectively.

河北省自然基金（B2011405007）；国家自然基金（21177155）；河北北方学院创新人才（CXRC1301，CXTD1306）；河北省食品药品监督管理局（PT2014051）资助项目