You are here:
Analysis of per- and polyfluorinated alkyl substances (PFAS) of sub-sampled water matrices with online solid phase extraction/isotope dilution tandem mass spectrometry
Citation:
Sanan, T. AND M. Magnuson. Analysis of per- and polyfluorinated alkyl substances (PFAS) of sub-sampled water matrices with online solid phase extraction/isotope dilution tandem mass spectrometry. JOURNAL OF CHROMATOGRAPHY A. Elsevier Science Ltd, New York, NY, 1626:461324, (2020). https://doi.org/10.1016/j.chroma.2020.461324
Impact/Purpose:
This study describes development and validation of an analytical method to quantify perfluoroalkyl substances (PFAS) in water matrices intended to support high throughput treatment study efforts in-house. It is intended to also describe methodological improvements in study of PFAS which may improve data quality and reduce analytical errors.
Description:
In the laboratory analysis of aqueous samples of per- and poly- fluoroalkyl substances (PFAS), sorption of PFAS onto surfaces of laboratory materials has been frequently reported. Due to the often complex and poorly understood nature of such sorption, workarounds have often included use of whole samples only, along with sample vessel rinsing to desorb active surfaces. The resulting methods tend to require considerable sample preparation times and preclude typical activities such as aliquoting and dilution of samples. This manuscript reports an approach for PFAS analysis which tolerates subsampling from vessels including centrifuge tubes and autosampler vials. By optimizing the use of solvent to avoid PFAS retention on subsampling vessels, the infrequently reported technique of online solid phase extraction (SPE) is used to concentrate a 5 mL sample to improve sensitivity and allow for removal of matrix interferences. In conjunction with UPLC to separate out the suite of PFAS target analytes for measurement via tandem mass spectrometry, isotope dilution is used to help quantify the aggregate effects of analyte sorption to sample containers, recovery through the SPE sorbent, and ionization effects in the mass spectrometer interface. Statistically based method detection limits ranged from sub ng/L to single digit ng/L for carboxylate, sulfonate, and sulfonamide PFAS analytes from C4 to C12 in length, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and HFPO-DA. Linear responses were studied from 0.25 to 4000 ng/L. Sample holding times were established as 14 days for all analytes. Matrix effects relevant for drinking water treatment studies, such as cations, organic carbon, and competing PFAS compounds, were found to not impact method performance within QC criteria consistent with study data quality objectives.
URLs/Downloads:
DOI: Analysis of per- and polyfluorinated alkyl substances (PFAS) of sub-sampled water matrices with online solid phase extraction/isotope dilution tandem mass spectrometry
Free access through PubMed Central