This work reports the development of a Fabry-Perot Interferometry (FPI) based optical fibre to detect perfluorooctanoic acid (PFOA) and other perfluoroalkyl substances (PFAS) in aqueous solutions. A novel and simple sensor fabrication procedure utilizing an immersion precipitation-based phase inversion process to form a thin polyvinylidene fluoride (PVDF) coating at the end-faces of freshly cleaved optical fibres is presented. The PVDF coating was rich in the electroactive β-phase, which enhances dipole-dipole and hydrophobic interaction with PFAS at binding sites. Sensor testing with model PFOA solutions showed that the PVDF coated FPI optical fibre can detect PFOA. The change in optical path difference (OPD) with change in PFOA concentration was considered as a measure of sensitivity and it corresponded to a value of 0.9 to 5 nm/ppm for PFOA. In real PFAS solutions obtained from fire-fighting foams, this value was found to be significantly more sensitive at 178 nm/ppb.

这项工作报告了基于Fabry-Perot干涉术（FPI）的光纤的开发，该光纤可检测水溶液中的全氟辛酸（PFOA）和其他全氟烷基物质（PFAS）。提出了一种新颖且简单的传感器制造程序，该程序利用基于浸没沉淀的相转化工艺在新近切割的光纤端面上形成薄的聚偏二氟乙烯（PVDF）涂层。PVDF涂层富含电活性β相，可增强结合位点与PFAS的偶极-偶极和疏水相互作用。使用型号PFOA解决方案进行的传感器测试表明，涂有PVDF的FPI光纤可以检测到PFOA。随PFOA浓度的变化而变化的光程差（OPD）被认为是灵敏度的量度，其对应于PFOA的值为0.9至5nm / ppm。