Infrared fiber-optic sensors for PFAS detection and analysis in complex water matrices

Max-IR Labs develops advanced infrared sensor platforms for environmental and industrial monitoring, with detection of per- and polyfluoroalkyl substances (PFAS) in water and reverse osmosis (RO) brine presented as a representative application. PFAS, often referred to as “forever chemicals,” persist in the environment and bioaccumulate in ecosystems and humans, driving increasing regulatory scrutiny and remediation efforts. During water treatment, PFAS can become concentrated in RO brine, making monitoring of brine streams critical for disposal and compliance. However, RO brine presents a particularly challenging sensing matrix due to high salinity and elevated concentrations of organic and inorganic species, including carbonate, nitrate, sulfate, ammonium, and total dissolved solids, which interfere with conventional analytical approaches. Max-IR Labs has developed the Ion-Selective Mid-InfraRed (ISMIRTM) field sensing platform validated against standard laboratory analytical techniques showing good agreement at concentrations near 1 ppb in complex municipal reverse osmosis (RO) concentrate. These results demonstrate that ISMIR™ provides a practical alternative to laboratory-dependent PFAS analysis, enabling continuous monitoring, treatment optimization, and informed decision-making for remediation and industrial water management.