Cucurbit(n)uril-functionalized magnetic composite for the dispersive solid-phase extraction of perfluoroalkyl and polyfluoroalkyl substances in environmental samples with determination by ultra-high performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have raised serious public health concerns because of their potential adverse effects in humans as revealed by toxicological and epidemiological research. However, routine monitoring of PFASs is still challenging due to their trace levels in various environmental and biological matrices. In this study, magnetic composite materials based on iron (II, III) oxide (FeO with surface functionalization by cucurbit(n)uril (CB(n)) (FeO@CB(n)) (n = 6, 7, 8), were prepared and evaluated as new adsorbents for the magnetic solid-phase extraction of nine PFASs in lake water, tap water and fish muscle samples. The FeO@CB(n) was characterized to examine their surface morphologies, sizes magnetism and thermal stability. Featuring good aqueous solution dispersibility, the macrocyclic structure of FeO@CB(n) was also endowed with strong host-guest interactions, allowing extraction and enrichment capability towards the PFASs in complex matrices. MSPE using FeO@CB(7) combination with ultra-high performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry, gave satisfactory quantitative analytical performance with low limits of detection of 0.004-0.04 µg L and limits of quantification of 0.005-0.1 µg L, linearities ranging from 0.01 to 10 µg L with high coefficients of determination (R ≥ 0.993), and enrichment factors (15-76) for the nine target PFASs. The method proved to be effective for the enrichment and analysis of trace levels of PFASs in genuine environmental water and fish muscle samples, indicating that FeO@CB(7) has promising applicability as an adsorbent for these contaminants.