Synthesis of 3-fluorobenzoyl chloride functionalized magnetic sorbent for highly efficient enrichment of perfluorinated compounds from river water samples

A novel type of magnetic nanoparticles, 3-fluorobenzoyl chloride functionalized magnetic nanoparticles (Fe3O4@SiO2@FBC MNPs) was successfully synthesized. It was applied to the extraction and determination of perfluorinated compounds (PFCs) by coupling with ultra-high performance liquid chromatography with tandem triple quadrupole mass spectrometry (UHPLC-MS/MS). Due to the fluorous-fluorous interaction, the magnetic nanoparticles displayed excellent extraction performance for 6 PFCs, including perfluoroheptanoic acid (PFHpA), perfluorodecanoic acid (PFDA), perfluorododecanoic acid (PFDoA), perfluorotetradecanoic acid (PFTeDA), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). The UHPLC separation of PFCs was very quick and could be achieved within 6 min. Various factors that may influence the magnetic solid-phase extraction (MSPE) efficiency, such as sorbent amount, desorption solvent, extraction time, pH value of water samples and sample volume, were investigated in detail. Under the optimum conditions, the linear ranges of six PFCs were 0.25-25 ng/L with the limits of detection (S/N = 3) ranging from 0.01 to 0.06 ng/L. Finally, the method was successfully applied to different river water samples, and the recoveries were in the range of 89.34-111.32%. These results indicated that the prepared Fe3O4@SiO2@FBC sorbents could efficiently enrich PFCs and that the proposed method is reliable.