Determination of per- and polyfluoroalkyl substances in tissue using QuEChERS extraction followed by novel enhanced matrix removal mixed-mode passthrough cleanup with LC-MS/MS detection.

A novel multiresidue method was developed and validated for the quantification of 40 per- and polyfluoroalkyl substances (PFAS) in fish, poultry and terrestrial animal muscle tissues. The method integrates QuEChERS extraction with an enhanced matrix removal (EMR) mixed-mode passthrough cleanup, followed by LC-MS/MS analysis. Validation was performed using tilapia, chicken, and pork matrices, assessing method suitability, selectivity, method detection limits (MDLs), limits of quantitation (LOQs), quantitation accuracy, intra- and inter- batch precision, internal standard recovery and repeatability (both extracted and non-extracted). The method was further cross-validated in cod, canned tuna, beef, and turkey, evaluating suitability and selectivity, MDLs, LOQ, and accuracy and precision at LOQ level. The new approach met all acceptance criteria outlined in EPA Method 1633 for tissue matrices, as well as the requirements of relevant EU regulations and AOAC SMPR guidelines. Target quantitation accuracy (apparent recovery) ranged from 72 - 151 % with over 95 % of analytes achieving accuracy within 80 - 120 % range. Precision, expressed as relative standard deviation (RSD), was below 20 % for all compounds across all tested tissue matrices. Internal standard recoveries, both extracted and non-extracted ranged, ranged from 57 to 202 %, with RSD below 9.4 %. Validated LOQs ranged from 0.05 - 1.25 ng/g, while calculated MDLs spanned 0.003 to 0.185 ng/g across the various tissue matrices. Compared to the conventional solvent extraction and solid phase extraction (SPE) approach outlined in EPA Method 1633, this method demonstrated enhanced accuracy, precision, and operational efficiency, resulting in significant time and cost savings.