From Unregulated to Unavoidable: High-Throughput LC–MS/MS Analysis of Ultra-Short and Short Chain PFAS in Drinking Water with Automated Sample Preparation

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Prepared by O. Shrestha1, R. Suzuki2, T. Anderson3, E. Wang4, T. Liden1, L. Miller1
1 - Shimadzu Scientific Instruments, 7102, Riverwood, Dr, MD, Columbia, United States
2 - Shimadzu Scientific instrument, 7102, Riverwood, Dr, MD, Columbia, United States
3 - ePrep, , , United States
4 - Shimadzu Scientific instrument, , , United States


Contact Information: [email protected]; 469-371-5175

ABSTRACT

Ultra-short and short chain per- and polyfluoroalkyl substances (PFAS; C1–C4 ) are highly polar, low-molecular-weight compounds that remain largely uncharacterized in drinking water despite potential health and environmental concerns. Their analysis is challenging due to poor chromatographic retention, low molecular weight, and susceptibility to background contamination.
We developed a high-throughput LC–MS/MS workflow with automated sample preparation for targeted quantification of C1–C4 PFAS. Target analytes included TFA, TFMS, PFPrA, PFEtS, PFBA, PFPrS, and PFBS, using ¹³C-labeled TFA as an internal standard. Samples were prepared using an automated ePrep ONE sample preparation workstation equipped with PFAS-free tubing, glass syringes, and PFAS-grade solvents. Chromatographic separation was achieved in 8 minutes on a polar-embedded IBD column with a delay column, and analysis was performed on a Shimadzu LC–MS/MS 8065 XE triple quadrupole system operated in multiple reaction monitoring mode. Drinking water from multiple local tap sources was spiked at three concentration levels with ≥7 replicates to assess recovery and method robustness.
Calibration curves were linear over 10-1000 ng/L (R² > 0.99), with recoveries of 70–130% and %RSDs below 20%. Background TFA was observed during method development in pipette tips, HPLC vials, acetic acid, and solvents; each source was systematically evaluated and mitigated. TFA was detected in five of seven local tap water sources at concentrations of 500-1000 ng/L , confirmed by standard addition experiments.
This workflow enables sensitive, selective, and high-throughput quantification of ultra-short and short-chain PFAS at low-ppt levels and demonstrates robustness and suitability for routine monitoring of highly mobile and persistent C1–C4 PFAS in drinking water. We will present the detailed outcomes from the method validation and background mitigation strategies.