Collaborative Research: Probe PFAS Using Polymer Substrates Through Interfacial Interactions

Per- and poly-fluoroalkyl substances (PFAS) have raised significant public health concerns due to their possible toxicity. They are often called "forever chemicals" because they persist for long periods in the environment. PFAS can contaminate groundwater supplies. Recent reports suggest that PFAS is present in the drinking water of 200 million Americans. The problem is especially severe in communities that lack municipal water supplies and rely on groundwater. Large-scale PFAS monitoring is expensive. This project will advance a new PFAS-detection technology that is faster, cheaper, and more sensitive than current detection methods. The project will also raise awareness of PFAS risks and mitigation strategies. Additional benefits include research opportunities for undergraduate students and undergraduate coursework in entrepreneurship. The project will advance a new method called Molecule-Probed Raman Spectroscopy (MPRS) for pollutant detection. MPRS relies on molecular probes that are attached to a polymer surface. This is different from state-of-the-art Raman methods which detect C-F bonds in PFAS directly, without using molecular probes. In MPRS, when the -CF group of the PFAS interacts with the molecular probe, there is a change in the Raman signal of the molecular probe. By monitoring this change in signal, MPRS can detect even low levels of PFAS rapidly. The project will integrate experiments with density functional theory and molecular dynamics simulations to discover the interactions between PFAS and polymers in aquatic environments. The key objectives of this research are to: (1) understand fundamental mechanisms of how interactions between PFAS and molecular probes amplify Raman signals and therefore discover new probes for PFAS detection, (2) investigate factors that influence the PFAS adsorption, and (3) explore how salts impact molecular interactions and PFAS detection. This project will create a portable sensor for ultra-sensitive, rapid quantification of PFAS from a variety of water sources such as groundwater, brackish water, and blood. The team will develop a new interactive seminar on PFAS targeting K-12 students, their parents, and the general public. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.