In situ solvothermal synthesis of metal–organic framework coated fiber for highly sensitive solid-phase microextraction of polycyclic aromatic hydrocarbons

• To develop a facile and simple covalent bonding SPME coating fiber preparation method.
• In situ solvothermal synthesis of robust UiO-66 coating via covalent bonding.
• UiO-66 coated fiber showed excellence stability and extraction efficiency for SPME of polycyclic aromatic hydrocarbons.
• UiO-66 coated fiber gave low detection limit, wide linearity and good reproducibility for polycyclic aromatic hydrocarbons.

The present work reported a facile and simple in situ solvothermal growth method for immobilization of metal–organic framework UiO-66 via covalent bonding on amino functional silica fiber for highly sensitive solid-phase microextraction (SPME) of ten polycyclic aromatic hydrocarbons (PAHs) by coupling with gas chromatography–mass spectrometry (GC–MS) analysis. The developed SPME coated fiber has been characterized through SEM, TGA and XRD, confirmed the coating thickness of ∼25 μm with high thermal and chemical stability. Under optimized conditions, the obtained method exhibited satisfactory linearity in range of 1.0–5000.0 ng L−1 for all the PAHs. The low detection limits were from 0.28 ng L−1 to 0.60 ng L−1 (S/N = 3). The UiO-66 coated fibers showed good repeatability (RSDs less than 8.2%, n = 5) and satisfying reproducibility between fiber to fiber (RSDs less than 8.9%, n = 5). This method was successfully used for simultaneous determination of ten PAHs from Minjiang water and soil samples with satisfactory recoveries of 87.0–113.6% and 83.8–116.7%, respectively. Experimental results shows that the chemical bonding approach has dramatically improve the stability and lifetime of pure MOFs coating for SPME in sample pretreatment.