A ppt level PFOS (perfluorooctanesulfonic acid) Sensor based on an Eco-Friendly Chitosan Biopolymer

Per- and poly-fluoroalkyl substances (PFAS) are persistent environmental pollutants used globally in various industries. In this work, we have demonstrated a novel chitosan based PFOS (perfluorooctanesulfonic acid, one of the most harmful PFAS) sensor by taking advantage of electrostatic interactions between the amino groups of chitosan biopolymer and the anionic PFOS. As a proof-of-concept device, a flexible three-electrode electrochemical sensor was designed and fabricated. The sensor demonstrated rapid parts-per-trillion (ppt) level PFOS detection relevant to environmental regulations along with other advantages such as its low cost, facile, and eco-friendly fabrication method.