Superfund Research Program
Development of a Commercial Assay for the Rapid and General Detection of PFAS in Environmental Matrices (Phase I)
Project Leader: Anuradha Singh
Grant Number: R43ES030677
Funding Period: Phase I: April 2021 - September 2021
Polyfluoro- and perfluoroalkyl substances (PFAS) are a group of highly fluorinated alkanes. Members of this family are known to be persistent and bioaccumulative. PFAS are associated with unfavorable health outcomes in human and animal models. Several public health agencies as well as scientists have published articles that indicate the presence of PFAS in human blood, serum, milk, cord blood, and tissues. Currently, detection of about a dozen of these chemicals out of more than a thousand of this class is performed using LCMS/MS. However, prior to analysis many purification steps are required to eliminate interfering species. Furthermore, the necessity of internal standards for the detection of PFAS, and the lack of pertinent internal standards dramatically reduces the scope of PFAS-detection. Currently, PFAS testing is a lengthy and costly undertaking that represents a major scientific bottleneck. Thus, there is an urgent need for a real-time detection technology that can sense a broad range of PFAS without pretreatment of sample, or expensive instrumentation. Implementation of such a product will allow better understanding of the fate of PFAS within the environment and their impact on human health. The research team's objective is to develop the pre-treatment free detection of PFAS in environmental matrices by coupling the key fluorous phase property with a highly sensitive fluorescence technology. In phase 1, the research team will apply the specific fluorous-fluorous interaction strategy to provide the adequate selectivity to preclude any associated purification steps. Fluorous tethered fluorescent dyes will be covalently immobilized on a glass surface. Initially, prior to exposure to PFAS, these fluorescent dyes will exist as excimers resulting from their close proximity to each other, the fluorescent probe turns the fluorescence on. Upon exposure to PFAS analytes, the analytes will be sequestered to the fluorous region of the probe due to specific fluorous-fluorous affinity. This will cause a physical disruption of the excimers, resulting in the fluorescence turn off of the excimer and a simultaneous turn on of the monomer emission. To achieve the proposed goal, in phase I the following specific aims will be pursued: specific aim: 1) attachment of the fluorescent dye to the fluorous molecule, 2) immobilization of fluorous-dye array on glass surface, and 3) evaluation of fluorescence on-off of fluorous-dye glass surface with PFAS-samples. Ultimately the approach developed here will lay the groundwork for the development of a product that is expected to enable a broad range of researchers to study many types of effects on human health caused by PFAS.