Only 15 minutes to detect PFAS in aqueous samples
PFAS (poly- and perfluorinated alkyl substances) are considered forever chemicals because they are hardly degradable in water and soil, but also in the human body. Many of the roughly 10,000 PFAS are now classified as harmful to health, which is why an EU-wide restriction under REACH is currently being prepared. For rapid and reliable monitoring, a new development from BAM offers a promising alternative to complex laboratory analyses: a microfluidic sensor system for on-site detection of PFAS within 15 minutes.
The results achievable with the new method were published in December 2025 in Nature Communications and selected for the “Editor’s Highlights” section as one of the most important articles in the field of materials science and chemistry.
“PFAS are a global problem. With our technology, we are laying the foundation for rapid on-site analyses that help authorities and companies monitor and remediate contaminated sites,” says Knut Rurack, an expert in chemical and optical sensing at BAM.
Core-shell nanoparticles in a microfluidic system
PFAS detection is based on a newly developed fluorescent indicator, a boron-dipyrromethene dye with guanidine as receptor molecule. The PFAS molecule to be detected is bound to this via a protonation-induced, ion-pairing-assisted hydrogen bond, and this binding triggers fluorescence.
This indicator substance is embedded in a molecularly imprinted polymer (MIP), which forms the outer shell of the nanoparticle. The core consists of a silicon oxide nanoparticle that contains another fluorescent dye as a reference. These core–shell nanoparticles are integrated into a microfluidic system in which the fluorescence is excited with a laser diode and detected using USB spectrometry.
Successful tests with PFOA
The article in Nature Communications describes the details of the production of the nanoparticles and the microfluidic system and shows, using perfluorooctanoic acid (PFOA), that a detection accuracy of 11 µM PFOA in water can be achieved with the new indicator substance.
“Our goal was a robust, user-friendly and scalable system. The combination of materials science and microfluidics opens up new avenues for monitoring cleaning and remediation processes in environmental management – not only for PFAS, but also for other pollutants,” explains Knut Rurack.
Link to the publication
Image source: photo by Photorama/Pixabay, processed.