Portable electrochemical sensors for per- and polyfluoroalkyl substances: Design, challenges, and opportunities for field deployment

The widespread presence of per- and polyfluoroalkyl substances (PFAS) in the environment presents a complex global challenge due to their persistence, resistance to degradation, and harmful effects. Electrochemical sensors offer the sensitivity needed to detect PFAS at regulatory limits and show promise for large-scale environmental monitoring without the need for costly laboratory equipment. This review highlights recent advances in electrochemical sensing technologies and their potential as field-deployable devices for rapid screening and on site PFAS detection. Examples include sensor platforms based on redox-active reporters, molecularly imprinted polymers (MIPs), redox dyes, metal organic frameworks (MOFs), covalent organic frameworks (COFs), nanoparticle impacts, and nanobubble and nanopore technologies, coupled with direct or indirect signal transduction strategies. We discuss promising sensor designs and detection mechanisms and outline the key challenges and future directions needed to advance their practical deployment in environmental monitoring applications.