The Importance of Sorbent Mass to Sample Volume for the Extraction of PFAS from Drinking Water Using Weak Anion Exchange SPE

Polyfluoroalkyl Substances (PFAS) in the Environment (Session 3)
Oral Presentation

Prepared by M. Giardina
Agilent Technologies, 2850 Centerville Rd, Wilmington, DE, 19808, United States


Contact Information: matthew_giardina@agilent.com; 302-636-8211


ABSTRACT

Regulated methods for the extraction of PFAS from drinking water using solid phase extraction specify a sorbent mass to sample volume ratio. This is to ensure the extraction of a sufficient mass of PFAS target compounds to achieve sufficient instrument detectability and to minimize the potential of solute breakthrough during sample loading and cartridge rinsing. In methods specifying weak anion exchange resin, it is typical to use 500 mg sorbent for 250 mL water samples. However, there are some drawbacks to using a large bed mass for extractions. Generally, larger bed masses require greater eluent volumes to quantitatively elute the solutes from the sorbent. In turn, greater eluent volumes require more time and energy to evaporate the eluate to dryness before reconstitution in the analysis solvent. When properly optimized, smaller bed masses can reduce the costs of solvents and sorbent in addition to increasing lab throughput efficiency by reducing the time required for solvent evaporation. In this presentation, the optimization of sorbent bed mass to sample volume ratio is investigated for a polymeric weak anion exchange resin for the extraction of PFAS compounds from water. The results will be evaluated based on the strict quality control requirements as specified in EPA method 533.