Constructing perfluorinated UiO-67 for enrichment of polycyclic aromatic hydrocarbons in seawater and seabed sediments

To investigate the ocean contamination caused by polycyclic aromatic hydrocarbons (PAHs), UiO-67/perfluorooctanoic acid (UiO-67/PFOA) was synthesized through solvent-assisted ligand incorporation method. The UiO-67/PFOA was then served as an adsorbent in headspace solid-phase microextraction (HS-SPME) technology for collecting and concentrating trace PAHs. The addition of the PFOA improved the hydrophobicity and stability of the UiO-67/PFOA coating, and the C-F functional group in UiO-67/PFOA could form the pseudo hydrogen bonding with the CH on the benzene ring of PAHs, which endowed the UiO-67/PFOA with 1.60-4.63 times enrichment performance for PAHs than UiO-67. Under optimal conditions, the wide linear ranges of PAHs (0.01-20 ng·mL^-1) with good coefficients of determination (R² ≥ 0.9950) and low limits of detection (LODs, 0.003-0.008 ng·mL^-1) were obtained. The recoveries of five PAHs from spiked seawater and seabed sediment by the developed method ranged from 81.14 % to 116.0 % with satisfactory results. This work provided a good adsorbent for the enrichment of trace PAHs in complicated environments and a new approach for the subsequent synthesis of adsorbents with good enrichment performance.