EPA 533 and 537.1 with the Novel LCMS-8050RX: Demonstration of Instrument and Method Performance to meet PFAS regulatory levels

Význam tématu

Per- and polyfluoroalkyl substances (PFAS) persist in the environment and pose serious health risks even at ultra-trace concentrations. Regulatory agencies such as the U.S. EPA have established stringent maximum contaminant levels for PFAS in drinking water, driving the need for highly sensitive, accurate, and rapid analytical methods.

Cíle a přehled studie

This study evaluates the performance of the Shimadzu LCMS-8050RX combined with a Nexera LC system for EPA Methods 533 and 537.1 (EPAM533 and EPAM537.1). Key objectives include assessing instrument detection limits, linearity, accuracy, precision, and runtime reduction while maintaining robust PFAS separation and quantitation.

Použitá metodika a instrumentace

• Liquid chromatography: Shimadzu Nexera LC with gradient elution (5–95% acetonitrile) and PFAS delay column
• Mass spectrometry: Shimadzu LCMS-8050RX equipped with novel RX probe for improved nebulization and heat distribution
• Analytical columns: Shim-pack GIST C18 (2.1×50 mm, 3 µm) for EPA 533; Shim-pack Velox SP-C18 (2.1×50 mm, 2.7 µm) for EPA 537.1
• Mobile phases: 2 mM ammonium acetate in water (A) and LC-MS grade acetonitrile (B)
• Run times: 15 minutes for EPAM533, 18 minutes for EPAM537.1
• Calibration: Isotope-dilution standards analyzed in prescribed solvent composition; replicate injections (n=20) for detection limit determination

Hlavní výsledky a diskuse

• Linearity: Correlation coefficients (R²) ≥ 0.996 across target analyte ranges (ppt to ppb).
• Instrument detection limits (IDL) after 250× concentration achieved low-ppt to sub-ppt (ppq) levels, meeting or exceeding EPA criteria.
• Accuracy at LOQ ranged from 70 % to 140 %, with most analytes within 80 %–120 %; precision (%RSD) was generally below 15 %.
• Run time reduction: Combined methods required ~19 minutes less instrument time without compromising chromatographic resolution or sensitivity.
• RX probe benefits: Enhanced heat distribution and nebulization improved signal stability and reduced variability in replicate analyses.

Přínosy a praktické využití metody

This optimized workflow enables high‐throughput, reliable PFAS monitoring in drinking and source water laboratories. Its robust performance supports regulatory compliance, routine quality assurance/quality control (QA/QC), and rapid response to emerging environmental contamination concerns.

Budoucí trendy a možnosti využití

Future developments may include integration of automated sample preparation, expansion of PFAS target lists and non-target screening using high-resolution mass spectrometry, adaptation to complex matrices (soil, biota), and implementation of AI-driven data processing to accelerate decision-making in environmental monitoring.

Závěr

The Shimadzu LCMS-8050RX with RX probe demonstrates exceptional sensitivity, reproducibility, and reduced runtime for EPA Methods 533 and 537.1. This analytical blueprint surpasses current detection requirements, offering a powerful solution for routine PFAS analysis in environmental and drinking water laboratories.

Reference

• Rosenblum L & Wendelken S. Method 533: Determination of Per- and Polyfluoroalkyl Substances in Drinking Water by Isotope-Dilution Anion Exchange Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry. U.S. Environmental Protection Agency, Washington, DC, 2019.
• Shoemaker J & Tettenhorst D. Method 537.1: Determination of Selected Per- and Polyfluorinated Alkyl Substances in Drinking Water by Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS). U.S. Environmental Protection Agency, Washington, DC, 2020.