To Isolation and Beyond: A New Mixed Mode Column Approach for PFAS Chromatography

Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Prepared by K. Organtini, K. Rosnack
Waters Corporation, 34 Maple St, Milford, MA, 01757, United States

Contact Information: [email protected]; 508-482-3242


Per- and polyfluorinated alkyl substances (PFAS) are one of the most commonly discussed and researched environmental contaminants. This is due in part to how widespread and impactful PFAS contamination has become, but also from increasing media awareness. Initially, most focus was on monitoring PFAS in water, mainly drinking water, but the prominence of these compounds in everyday items have expanded analysis to other matrices such as food, cosmetics, and human biofluids. As more research is focused on PFAS exposure and impacts, analytical techniques have been advancing as well to help progress research and monitoring efforts.
One of the constantly changing areas in PFAS analysis is the list of PFAS compounds that are being targeted for. One trend impacting this is the movement of manufacturers from using long chain PFAS to short chain and ultra-short chain PFAS. As the chain length shortens, chromatography can become more complicated, not only from a perspective of the analytical column the sample is separated on, but also regarding the functionality of the isolator column that is crucial to delaying PFAS interference from the LC system. These compounds require advancements in chromatographic techniques to properly detect and quantify in samples.
Faced with this challenge, a new mixed mode column (XBridge™ Premier BEH™ C18 AX Column) was evaluated as both an isolator column and an analytical column to provide better retention of short chain and ultra-short chain PFAS. This presentation will demonstrate how this column was applied in both cases to not only delay chromatographic interference, providing accurate sample quantitation, but also to extend the possible list of PFAS analyzed in a single injection to include PFAS chain lengths