NEMC: Automated Preparation Solutions for PFAS Analysis in Environmental Samples

Significance of the Topic

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants of growing concern due to their resistance to degradation, widespread occurrence, and potential health risks. Reliable and efficient analytical workflows are essential to support regulatory compliance, environmental monitoring, and assessment of human exposure.

Objectives and Overview

This work presents automated sample preparation and analysis solutions for PFAS in environmental matrices. It summarizes Thermo Fisher Scientific offerings, including off-line and on-line solid-phase extraction (SPE) for water, accelerated solvent extraction (ASE) for soils, and combustion ion chromatography (CIC) for non-targeted screening. The aim is to demonstrate high-throughput, reproducible methods that meet or exceed EPA guidelines.

Methodology and Instrumentation

The following automated workflows are described:

• Off-line SPE using the AutoTrace 280 PFAS SPE instrument with PEEK tubing, positive pressure, and programmable flow for EPA Method 537.1.
• On-line SPE with the TriPlus RSH EQuan 850 autosampler coupled to LC–MS for direct preconcentration and analysis in less than 30 minutes.
• Accelerated solvent extraction of soils using the Dionex ASE 350 system operating at elevated temperature and pressure for rapid PFAS release.
• Combustion IC screening (AOF) implemented on a CIC system for total organically bound fluorine in aqueous samples.

Used Instrumentation

• AutoTrace 280 PFAS SPE instrument
• TriPlus RSH EQuan 850 autosampler
• Vanquish HPLC system with PFAS-free kit
• TSQ Quantis mass spectrometer
• Dionex ASE 350 accelerated solvent extractor
• Combustion ion chromatography platform with Dionex IonPac columns

Main Results and Discussion

AutoTrace 280 SPE achieved mean recoveries of 84–120% and RSDs below 10% for 25 PFAS at fortified levels (16–80 ng/L), meeting EPA criteria. The EQuan 850 on-line SPE–LC–MS workflow demonstrated linear response and low detection limits (sub-ng/L) across diverse water matrices with RSDs under 10% and recoveries between 84% and 128%. ASE 350 extraction of soil yielded 71–110% recoveries for target PFAS within 25 minutes per sample. CIC-based AOF screening provided a rapid cumulative fluorine parameter, detecting total organically bound fluorine in wastewater and surface water samples, complementing targeted LC-MS/MS analysis and revealing unknown PFAS load.

Benefits and Practical Application

These automated workflows offer significant advantages:

• Reduced hands-on time and labor costs due to walk-up operation and parallel processing.
• Enhanced reproducibility and data quality by maintaining constant flow and pressure.
• Faster throughput, with analysis times cut from hours to minutes for on-line SPE.
• Comprehensive screening capability through AOF for non-targeted PFAS assessment.

Future Trends and Opportunities

Emerging needs include expansion of PFAS compound libraries, integration of high-resolution mass spectrometry for non-targeted profiling, and coupling with data-driven tools for rapid identification. Miniaturized and fully integrated sample-to-result platforms, as well as broader adoption of CIC for total fluorine screening, are expected to advance environmental monitoring and regulatory compliance.

Conclusion

Automated sample preparation solutions for PFAS analysis—ranging from off-line and on-line SPE to ASE and CIC screening—provide robust, high-throughput workflows that satisfy stringent performance standards. These methods support reliable environmental surveillance, facilitate efficient laboratory operations, and enable comprehensive evaluation of PFAS contamination.

References

EPA Method 533 and 537.1
ASTM, DIN, ISO standard CIC methods
Data courtesy of John Quick, ALS Environmental, and von Abercron et al.