LABOREXPO: Analysis of Per and Polyfluoroalkyl Substances (PFAS) an Analytical Challenge!

Importance of the Topic

PFAS are a large class of man-made chemicals characterized by strong carbon fluorine bonds that confer resistance to water oil and degradation. Their persistence and bioaccumulation pose health and environmental risks requiring reliable detection at trace levels.

Objectives and Article Overview

This work presents a targeted analytical method for quantifying 24 per and polyfluoroalkyl substances in complex matrices with emphasis on paper based food contact materials. The goal is to achieve high sensitivity specificity and reproducibility while controlling background contamination.

Methodology and Instrumental Setup

Sample extraction employs accelerated solvent extraction with methanol followed by filtration evaporation and reconstitution in methanol water. Chromatographic separation is performed on a C18 column with a PFAS delay column to remove background interferences. The mobile phase consists of 5 mmol ammonium acetate and methanol under a 10 minute gradient at 0.4 mL per minute. Mass detection uses a triple quadrupole system in negative electrospray mode with optimized temperatures and gas flows. Key MS transitions were established for each analyte.

Main Results and Discussion

Calibration curves exhibit excellent linearity across high and low concentration ranges with R2 values above 0.97. Precision is demonstrated by RSD values below 5% for most analytes. Limits of detection reach down to 0.01 pg per microliter. Recovery studies in spiked paper samples yield an average recovery of 88.7%, confirming method accuracy. The PFAS delay column effectively reduces carry over and laboratory background levels.

Benefits and Practical Applications

The method offers rapid ten minute runs suitable for high throughput monitoring of PFAS in food packaging water and environmental samples. Sensitivity meets regulatory requirements such as the 70 ng per liter advisory threshold. Integration of a delay column improves data quality by minimizing false positives from instrument background.

Future Trends and Application Opportunities

Ongoing enhancements include lowering limits of quantification further and extending the method to additional PFAS classes and real sample matrices such as food packaging and fast food materials. Combining this targeted approach with total oxidizable precursor assays can enable more comprehensive PFAS screening strategies.

Conclusion

The validated LC MS MS protocol provides a robust efficient and sensitive tool for comprehensive PFAS quantification. Its application supports quality control regulatory compliance and environmental risk assessment for diverse sample types.