Two-in-one platform based on conjugated polymer for ultrasensitive ratiometric detection and efficient removal of perfluoroalkyl substances from environmental water

Continuous emergence of persistent organic pollutants perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in various water bodies around the world poses a serious threat to the global ecosystem. The exploration of advanced detection/removal techniques to monitor/treat such type of toxicants is urgently required. Herein, we un -veiled a donor-acceptor type conjugated polymer PF-DBT-Im as a first-of-its-kind ratiometric fluorescent probe for vi-sual, amplified, and specific monitoring of PFOA and PFOS with ultra-low detection limits of 6.12 nM (PFOA) and 14.3 nM (PFOS), respectively. PF-DBT-Im undergoes strong aggregation after binding with PFOA/PFOS as evident by trans-mission electron microscopy, zeta potential measurements, and dynamic light scattering studies. This promotes inter-chain Forster resonance energy transfer process to endorse an obvious emission color change from blue-to-magenta under ultraviolet lamp excitation. Consequently, a smartphone-integrated portable device is fabricated for realizing rapid and on-site detection of PFOA/PFOS. Besides, a new class of magnetic adsorbent Fe3O4@NH2&F13 is also pre-pared and used in combination with PF-DBT-Im to remove PFOA/PFOS from the environmental water effectively and rapidly as confirmed by liquid chromatography-mass spectrometry analysis. Thus, utilizing the excellent signal amplification property of PF-DBT-Im and the remarkable magnetic separation capability of Fe3O4@NH2&F13, a mul-tifunctional system is developed for step-wise recognition and separation of PFOA/PFOS from the environmental water proficiently and rapidly.

Automated summary

The continuous emergence of PFOA and PFOS, persistent organic pollutants, in water bodies worldwide poses a serious threat to the global ecosystem. To effectively monitor and treat these toxicants, a ratiometric fluorescent probe called PF-DBT-Im was developed. This polymer demonstrates low detection limits and undergoes aggregation upon binding with PFOA/PFOS, allowing for easy visualization. Additionally, a smartphone-integrated device and a magnetic adsorbent, Fe3O4@NH2&F13, were utilized for rapid and efficient detection and removal of PFOA/PFOS from environmental water.