Foundation for Research and Technology-Hellas, Institute of Chemical Engineering Sciences, (FORTH/ICE-HT), Stadiou Str. Platani, 265 04, Patras, Greece.
Foundation for Research and Technology-Hellas, Institute of Chemical Engineering Sciences, (FORTH/ICE-HT), Stadiou Str. Platani, 265 04, Patras, Greece; Department of Physics, University of Patras, GR-26504, Patras, Greece.
Chemosphere. 2024 Sep;363:142916. doi: 10.1016/j.chemosphere.2024.142916. Epub 2024 Jul 21.
The detection of the highly toxic per- and polyfluoroalkyl substances, PFAS, constitutes a challenging task in terms of developing a generic method that could be rapid and applicable simultaneously to both long and short-chain PFAS at ppt concentration level. In the present study, the method introduced by the USA Environmental Protection Agency, EPA, to detect surfactants, using methylene blue, MB, which is identified an ideal candidate for PFAS-MB ion pairing, is extended at the lowest concentration range by a simple additional step that involves the dissociation of the ion pairs in water. In this work, Surface Enhanced Raman Scattering, SERS, is applied via Ag nanocolloidal suspensions to probe MB and indirectly either/or both short-chain (perfluorobutyric acid, PFBA) and long-chain (perfluoloctanoic acid, PFOA) PFAS downt to 5 ppt. This method, which can be further optimized to sub-ppt level via a custom-made SERS-PFAS dedicated Raman system, offers the possibility to be applied to either specific PFAS (both short and long-chain) in a targeted analysis or to total PFAS in a non-targeted analysis at very low detection limits, following any type of MB detection method in aqueous solutions and obviously with any type of SERS substrate.
检测高毒性的全氟和多氟烷基物质（PFAS），开发一种通用方法是一项具有挑战性的任务，该方法应能快速且同时适用于长链和短链 PFAS，检测浓度低至 ppt 级。在本研究中，美国环保署（EPA）用于检测表面活性剂的方法得到扩展，该方法使用亚甲蓝（MB）作为理想的 PFAS-MB 离子对候选物，通过一个简单的额外步骤，即在水中解离离子对，将其扩展到最低浓度范围。在这项工作中，通过银纳米胶体悬浮液应用表面增强拉曼散射（SERS）来探测 MB，并间接探测短链（全氟丁酸，PFBA）和长链（全氟辛酸，PFOA）PFAS 低至 5 ppt。该方法可以通过定制的 SERS-PFAS 专用拉曼系统进一步优化至亚 ppt 级，为靶向分析中特定 PFAS（长链和短链）或非靶向分析中总 PFAS 提供了可能，检测限非常低，可应用于任何类型的 MB 检测方法在水溶液中，并且显然适用于任何类型的 SERS 基底。
