Dong Bingqi, Wu Jing, Zhuang Yiru, Wang Fan, Zhang Yueling, Zhang Xiaona, Zheng Hui, Yang Lixin, Peng Lin
The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, PR China.
Institute of Transport Energy and Environment, Beijing Jiaotong University, Beijing 100044, China.
Anal Chem. 2023 Jan 17;95(2):695-702. doi: 10.1021/acs.analchem.2c02436. Epub 2023 Jan 4.
As the usage of long-chain perfluoroalkyl and polyfluoroalkyl substances (PFASs) may be gradually restricted, short-chain and even ultra-short-chain PFASs have been widely produced and used, which has put forward new requirements for the simultaneous analysis of the above substances. Using solid phase extraction two-fraction elution and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), an experimental method was established for the simultaneous analysis of ultrashort-chain, short-chain, and long-chain PFASs and the precursor perfluorohexanesulfonamide (FHxSA) in low-concentration water, such as tap water and bottled water. By optimizing the volume of methanol in the first-fraction elution, the concentration of ammonia in the second-fraction elution, and the concentration of ammonium acetate in the mobile phase, the high recovery and low detection limit (0.01-3 ng/L) were obtained. In addition, this method was used to measure nine tap water samples and six bottled water samples for validation, and the results showed that the concentration of PFASs in bottled water was lower than that in tap water. This study first reported the trifluoroacetic acid concentration in bottled water (6.61 ± 9.60 ng/L), which was lower than that in tap water (1712 ± 174 ng/L). The main substances in tap water and bottled water are both ultrashort-chain PFASs (C2-C3), accounting for more than 50%. There are few reports on the simultaneous analysis of ultrashort-chain, short-chain, and long-chain PFASs (C2-C18) and the precursor FHxSA in low-concentration water samples, and the new method can be further developed for different environmental media.
由于长链全氟烷基和多氟烷基物质（PFASs）的使用可能会逐渐受到限制，短链甚至超短链PFASs已被广泛生产和使用，这对上述物质的同时分析提出了新的要求。采用固相萃取二组分洗脱和超高效液相色谱串联质谱法（UPLC-MS/MS），建立了一种同时分析低浓度水（如自来水和瓶装水）中超短链、短链和长链PFASs以及前体全氟己烷磺酰胺（FHxSA）的实验方法。通过优化第一组分洗脱中甲醇的体积、第二组分洗脱中氨的浓度以及流动相中乙酸铵的浓度，获得了高回收率和低检测限（0.01 - 3 ng/L）。此外，该方法用于测定9个自来水样品和6个瓶装水样品进行验证，结果表明瓶装水中PFASs的浓度低于自来水中的浓度。本研究首次报道了瓶装水中三氟乙酸的浓度（6.61±9.60 ng/L），低于自来水中的浓度（1712±174 ng/L）。自来水和瓶装水中的主要物质均为超短链PFASs（C2 - C3），占比超过50%。关于低浓度水样中超短链、短链和长链PFASs（C2 - C18）以及前体FHxSA的同时分析报道较少，该新方法可针对不同环境介质进一步拓展。
