Analysis of Perfluorooctane Sulfonamidoethanols (FOSEs) and Fluorotelomer Alcohols (FTOHs) in Textiles by LC/MS/MS

Importance of the Topic

Perfluorinated compounds (PFCs) are widely used in textiles and consumer products for their water- and oil-repellent properties. Among them, fluorotelomer alcohols (FTOHs) and perfluorooctane sulfonamidoethanols (FOSEs) can degrade into regulated perfluoroalkyl acids. Sensitive and selective monitoring of these less-polar PFCs in textiles is essential for environmental and health compliance.

Objectives and Study Overview

This study presents the development of a targeted LC/MS/MS method on a Shimadzu LCMS-8050 triple quadrupole system to quantify four FTOHs (4:2, 6:2, 8:2, 10:2) and two FOSEs (N-MeFOSE, N-EtFOSE) in textile matrices. The goal is to achieve rapid separation, high sensitivity, and robust performance for routine testing.

Methodology

• Preparation of mixed calibration standards in acetonitrile/water covering 1–50 ng/mL for FTOHs and 0.02–1 ng/mL for FOSEs.
• Sample extraction: 1 g textile, 20 mL methanol, 30 min ultrasonic agitaton, centrifugation, and 0.22 µm filtration. Concentrated under nitrogen and reconstituted in 50:50 ACN/water.
• Chromatography on Shim-pack GIST C18 (2.1 × 100 mm, 2 µm) at 0.3 mL/min, 40 °C. Mobile phase A: 5 mM ammonium acetate in water; B: acetonitrile; gradient from 30% to 95% B over 18.5 min.
• ESI in negative mode; MRM quantifier transition [M+CH₃COO]⁻→CH₃COO⁻, qualifier transition precursor→precursor. Optimized collision energies via LabSolutions automated method.

Used Instrumentation

The analytical platform comprised a Shimadzu LCMS-8050 triple quadrupole mass spectrometer with heated ESI interface (250 °C), argon CID gas, nitrogen nebulizing/drying gases, and zero-air heating gas. Separation employed a Shim-pack GIST C18 column integrated with the LabSolutions data system.

Main Results and Discussion

• Chromatographic separation yielded sharp, baseline-resolved peaks for all six analytes within 14 min.
• Calibration curves were linear (R² > 0.999) over the tested ranges. LOQs for FTOHs were 0.5–3.7 ng/mL; LODs 0.2–1.2 ng/mL. FOSEs exhibited LOQs of 0.002–0.005 ng/mL and LODs of 0.001–0.002 ng/mL.
• Repeatability (n=6) showed peak area RSDs < 10% at low and high spiking levels.
• Matrix effects in methanolic textile extracts caused ion suppression between 30.5% and 95.7%, most pronounced for 10:2 FTOH. Clean-up improvements (e.g., SPE) are recommended.
• Extraction recoveries ranged from 62.8% to 107.6% for FTOHs and 98.2% to 142.9% for FOSEs, demonstrating adequate sample preparation efficiency.

Benefits and Practical Applications

• This LC/MS/MS workflow provides a direct, derivatization-free alternative to GC/MS methods and achieves high sensitivity for less-polar PFCs.
• The rapid analysis and robust quantitation support quality control, regulatory compliance, and routine monitoring of PFAS in textile and consumer product laboratories.

Future Trends and Applications

Method extension to additional per- and polyfluoroalkyl substances, integration of high-resolution mass spectrometry for non-target screening, and adoption of improved sample clean-up protocols will further enhance detection capability and broaden the scope of textile PFAS analysis.

Conclusion

A sensitive and reliable LC/MS/MS method was established for quantifying four FTOHs and two FOSEs in textile matrices, delivering excellent linearity, low detection limits, and good precision. Addressing matrix suppression via advanced cleanup will optimize performance for trace-level monitoring.

References

1. Renner R. Perfluorinated Sources Outside and Inside. Environ. Sci. Technol. 2004;38(5):80A.
2. Lee JX, Sun Z, Xing J, Tan JY, Zhan Z. A fast LC/MS/MS method for high sensitivity determination of 26 perfluorocompounds in textiles. ASMS 2016; Poster TP485.
3. Lahey CM, Ting GWE, Yeong HXC, et al. Fast and accurate analysis of fluorotelomer alcohols and acrylates using triple quadrupole GC-MS/MS. ASMS 2016; Poster ThP156.
4. Yeong HX, Olivia S, Lahey CM, Ting GWE, Loo LC. Fast screening and quantitation of perfluorinated sources from textiles using CI GC-MS. ASMS 2017; Poster TP295.