In the present study, a highly selective fluorous affinity-based dispersive liquid–liquid microextraction (DLLME) technique was developed for the extraction and analysis of per- and polyfluoroalkyl substances (PFASs) followed by high performance liquid chromatography tandem–mass spectrometry. Perfluoro-tert-butanol with multiple C-F bonds was chosen as the extraction solvent, which was injected into the aqueous samples with a dispersive solvent (acetonitrile) in a 120:800 (μL, v/v) mixture for PFASs enrichment. The fluorous affinity-based extraction mechanism was confirmed by the significantly higher extraction recoveries for PFASs containing multiple fluorine atoms than those for compounds with fewer or no fluorine atoms. The extraction recoveries of medium and long-chain PFASs (CF₂ > 5) exceeded 70%, except perfluoroheptanoic acid, while those of short-chain PFASs were lower than 50%, implying that the proposed DLLME may not be suitable for their extraction due to weak fluorous affinity. This highly fluoroselective DLLME technique can greatly decrease the matrix effect that occurs in mass spectrometry detection when applied to the analysis of urine samples. Under the optimum conditions, the relative recoveries of PFASs with CF₂ > 5 ranged from 80.6-121.4% for tap water, river water and urine samples spiked with concentrations of 10, 50 and 100 ng/L. The method limits of quantification for PFASs in water and urine samples were in the range of 0.6–8.7 ng/L. Furthermore, comparable concentrations of PFASs were obtained via DLLME and solid-phase extraction, confirming that the developed DLLME technique is a promising method for the extraction of PFASs in real samples.

在本研究中，开发了一种高度选择性的基于氟亲和力的分散液-液微萃取（DLLME）技术，用于萃取和分析全氟烷基物质和多氟烷基物质（PFAS），然后进行高效液相色谱串联质谱分析。选择具有多个CF键的全氟叔丁醇作为萃取溶剂，将其与分散溶剂（乙腈）以120：800（μL，v / v）的混合物注入水性样品中，以富集PFAS。基于氟亲和力的萃取机理得到了证实，与含较少或不含氟原子的化合物相比，含多个氟原子的PFAS的萃取回收率明显更高。中长链PFAS（CF ₂ > 5）超过70％（全氟庚酸除外），而短链PFAS的含量低于50％，这表明由于弱的氟亲和力，建议的DLLME可能不适合其提取。当应用于尿液样品分析时，这种高度氟选择性的DLLME技术可以大大降低质谱检测中发生的基质效应。在最佳条件下，CF ₂与PFAS的相对回收率 对于自来水，河水和尿液样品加标浓度分别为10、50和100 ng / L的> 5，其范围为80.6-121.4％。水和尿液样品中全氟辛烷磺酸的定量方法极限为0.6–8.7 ng / L。此外，通过DLLME和固相萃取获得了相当浓度的PFAS，证实了开发的DLLME技术是一种在实际样品中萃取PFAS的有前途的方法。