Development of an Automated Solvent Extraction Workflow, including Cleanup for PFAS Analysis of Solid Samples

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Poster Presentation

Prepared by A. Stell, B. Liu, M. Swasy
CEM Corporation, 3100 Smith Farm Rd., Matthews, NC, 28106, United States


Contact Information: [email protected]; 704-821-7015

ABSTRACT

The scientific community is very aware of the risks that per- and polyfluoroalkyl substances (PFAS) pose to human health and the environment. PFAS are notoriously resistant to biological and chemical degradation, resulting in notable environmental persistence. When combined with bioaccumulation, this has led to their presence throughout daily life, from drinking water and agricultural soils to the fish we eat. Sample preparation and detection methods have advanced more rapidly for water in comparison to solid samples. Solid matrices, including soils and tissues, require extraction and cleanup to address matrix interferences, complicating method development, standardization, and data consistency.
Significant progress has been made with solid-matrix methods such as EPA 1633A, ISO 21675, and ASTM D7968-23. Generally, these methods employ a solvent extraction followed by a separate cleanup protocol in order to isolate PFAS analytes of interest. This multi-step process can be time-consuming, inconsistent, and susceptible to human error. To address these limitations, a fully automated system was developed for integrated pressurized fluid extraction and cleanup. This work details the extraction, cleanup, and filtration of solid matrices in under fifteen minutes, enabling automated preparation followed directly by LC-MS/MS analysis.
To demonstrate system performance, soil and fish tissue samples were prepared for automated extraction coupled with in situ cleanup. LC-MS/MS analysis of the resulting extracts displayed good recoveries and reproducibility for native compounds and internal standards. Further, this approach is applicable to a wide range of solid and semi-solid matrices. These results suggest that this method enables a fast, reliable, and scalable workflow suitable for high-throughput PFAS testing laboratories.