Fast and Direct Detection of Perfluorocarboxlyic acids (PFCA) with SICRIT®-MS

Importance of the Topic

Per- and polyfluoroalkyl compounds, especially perfluorocarboxylic acids, pose a long-lasting environmental and health risk due to their widespread use and persistence. These substances can accumulate in water, soil, food, and consumer products, raising concerns over potential carcinogenic and mutagenic effects. Accurate and rapid detection of PFCAs is essential for environmental monitoring, regulatory compliance, and quality control in industry.

Objectives and Study Overview

This application note aims to demonstrate a direct, rapid, and non-targeted method to screen solid samples and coatings for PFCAs using the SICRIT ion source coupled to mass spectrometry. The study evaluates the feasibility of headspace analysis for real-life samples, including formulation powders and treated textiles, without any sample pretreatment.

Methodology and Instrumentation

Samples were presented directly in front of the SICRIT ion source, operating in negative-ion mode with plasma settings of 1.5 kV and 15 kHz. A Thermo LTQ Orbitrap XL system collected high-resolution full-scan spectra over the mass range 50 to 750 m/z at 30 000 FWHM resolution. Data processing and exact mass identification were performed with Xcalibur software, using a 5 ppm tolerance window. The setup can be adapted to triple quadrupole systems for targeted MS/MS studies and automated via PAL autosampler coupled to a GC-SPME module.

Main Results and Discussion

Direct headspace ionization enabled the detection of a homologous series of PFCAs from C3 to C9, identified as dominant [M-H]– ions with mass errors below 1.5 ppm. Most samples showed low or undetectable levels of PFOA, suggesting a shift toward shorter-chain alternatives in commercial formulations. Spectral comparison confirmed the presence of PFBA, PFPeA, PFHxA, and PFHpA in coating powders and textiles, demonstrating the method’s sensitivity and selectivity without prior extraction or chromatography.

Benefits and Practical Applications

• Eliminates laborious sample preparation and solvent use
• Provides soft ionization with minimal fragmentation for accurate mass analysis
• Enables rapid screening of solids, coatings, and textiles
• Delivers high-throughput capability through direct headspace sampling and potential automation

Future Trends and Potential Applications

Integration of SICRIT-MS with automated sampling systems and expansion to targeted MS/MS workflows can further streamline PFAS analysis. The approach can be extended to environmental matrices such as soil and water, as well as to non-targeted screening of emerging fluorinated contaminants. Development of standardized protocols may support regulatory monitoring and industrial quality control.

Conclusion

The SICRIT ion source offers a versatile and efficient platform for direct, non-targeted detection of perfluorocarboxylic acids in solid and coated samples. Its compatibility with existing LC-MS or GC-MS systems, combined with soft negative-ion ionization and high-resolution mass analysis, makes it an attractive tool for rapid PFAS screening in laboratory and industrial settings.

References

1. Larsen BS, Kaiser MA. Anal Chem. 2007;79(11):3966-3973.