Polymerizable monomer for selective PFAS capture via fluorophilic interaction and cavity recognition: Rational design and applications in removal and sensing

The environmental and health risks associated with per- and polyfluoroalkyl substances (PFAS) have attracted increasing regulatory scrutiny in recent years. However, efficient remediation and detection of PFAS remain challenging due to the absence of highly selective recognition mechanisms and suitable adsorbents. Herein, we synthesized a fluorophilic and hydrophobic monomer, 3-[2-(perfluorooctyl)-ethoxycarbonyl]pyrrole (F-pyrrole), and demonstrated its application in the recognition, removal, and sensing of PFAS. The pyrrole moiety imparts excellent film-forming capabilities, allowing electrodeposition on conductive substrates to construct non-imprinted and imprinted polymer films for distinct applications. For remediation, the F-pyrrole-based film enabled the potential-driven, directional removal of PFAS with varying chain lengths (primarily relying on hydrophobic and fluorophilic interactions), achieving a removal efficiency >92%. For sensing, by synergizing fluorophilic affinity with specific imprinted cavities, the polymer was extended to the development of a portable, cost-effective sensor for rapid PFAS detection (detection limit for perfluorononanoic acid = 19 ng/L), demonstrating enhanced selectivity for the target PFAS against structural analogues. Analysis of water samples collected from major rivers in southwest China yielded results comparable to those obtained by HPLC-MS/MS, highlighting the sensor's potential for large-scale PFAS screening. This study provides a novel strategy for developing a multi-functional fluorophilic monomer for selective PFAS removal and specific PFAS sensing.