Simultaneous Analysis of Ultrashort-Chain to Long-Chain (C1 to C10) and Alternative PFAS in Human Plasma and Serum

Importance of the Topic

Per- and polyfluoroalkyl substances (PFAS) span a broad range of chain lengths and polarities, with ultrashort-chain compounds (C1–C3) posing analytical challenges due to their high polarity and low chromatographic retention. Monitoring PFAS exposure in human plasma and serum is critical for assessing health risks, regulatory compliance, and advancing our understanding of these ubiquitous contaminants.

Study Aims and Overview

This study aimed to develop and validate a streamlined LC-MS/MS workflow for the simultaneous quantification of PFAS ranging from C1 to C10 carboxylic and sulfonic acids, plus four alternative PFAS, in human plasma and serum. A key objective was to integrate ultrashort-chain analytes into a single analytical protocol without lengthy sample preparation.

Methodology and Used Instrumentation

Sample preparation consisted of one-step protein precipitation of plasma or serum followed by direct LC-MS/MS analysis. A polar-embedded Ultra IBD column coupled with a PFAS delay column achieved satisfactory retention of ultrashort-chain PFAS under reversed-phase conditions. The optimized mobile phases were 5 mM ammonium formate with 0.1% formic acid (A) and acetonitrile (B) with a gradient from 20% to 95% B. The analysis was performed on a Waters Xevo TQ-S triple-quadrupole mass spectrometer interfaced with an Acquity UPLC system, using scheduled MRM in negative ESI mode.

Main Results and Discussion

Linearity for all target analytes was excellent (r2 > 0.995) across 0.05–40 ng/mL. Accuracy and precision evaluated in fortified fetal bovine serum yielded recoveries of 82.3–115% and RSDs below 11.3%. Analysis of NIST SRM 1950 plasma and SRM 1957 serum confirmed method validity, with most measured concentrations within 20% of reference values. Notably, the ultrashort-chain analyte TFA was retained effectively, reducing matrix interference and improving quantification reliability.

Benefits and Practical Applications

• Rapid sample processing: single-step precipitation reduces labor and potential losses.
• Comprehensive coverage: simultaneous measurement of C1–C10 and alternative PFAS.
• High robustness: suitable for routine biomonitoring, clinical studies, and QA/QC laboratories.

Future Trends and Application Opportunities

Emerging directions include expanding the analyte panel to novel PFAS, applying high-throughput automation, and adapting the protocol for other biological matrices (e.g., urine, tissues). Integration with exposomics and population-wide surveillance will further elucidate PFAS exposure pathways and health outcomes.

Conclusion

A reliable and user-friendly LC-MS/MS workflow was established for ultrashort- to long-chain PFAS in human plasma and serum. The method demonstrates excellent linearity, accuracy, and precision, offering a valuable tool for exposure assessment and research on PFAS health effects.

References

• No specific literature references were provided in the source text.