Approach based on multiple monolithic fiber solid-phase microextraction coupled to liquid chromatography-tandem mass spectrometry for sensitive determination of perfluoroalkyl acids in fish and seafood

A sensitive analytical approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with multiple monolithic fiber solid-phase microextraction (MMF-SPME) was developed for determination of perfluoroalkyl acids, including perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs) in fish and seafood. The MMF-SPME based on poly (vinylbenzyltrimethylammonium chloride/dodecafluoroheptyl acrylateco- ethylenedimethacrylate/divinylbenzene) monolith which contained abundant F atoms and quaternary amine groups was employed to effectively extract studied analytes. Various parameters affecting the extraction performance were investigated in detail. Under the most favorable conditions, the developed method displayed wide linear dynamic ranges with good coefficients of correlation (R-2 > 0.99). The limits of detection (LODs) and limits of quantification (LOQs) were in the ranges of 0.0062-1.5 mu g/kg and 0.021-5.0 mu g/kg, respectively. The relative standard deviation (RSD) values for infra-day and inter-day assay variability were less than 12% for all analytes. The introduced method was successfully applied to detect low levels of PFCAs and PFSAs in the muscle of fish, shrimp and shellfish samples. Recoveries at low, medium and high fortified concentrations were in the ranges of 80.2-119%, and the RSDs varied from 0.3% to 11% for all analytes. The satisfactory results well demonstrate that the developed approach is sensitive and reliable in the monitoring of trace PFCAs and PFSAs in fish and seafood.