In situ hydrothermal growth of a dual-ligand metal-organic framework film on a stainless steel fiber for solid-phase microextraction of polycyclic aromatic hydrocarbons in environmental water samples

Effective enrichment and determination of polycyclic aromatic hydrocarbons (PAHs) in environmental aqueous solutions is still a major challenge because of their poor solubility and low concentration in the environmental matrix. Solid-phase microextraction (SPME) has been proven to be an effective technique for analyzing trace analytes from environmental samples. Herein, we report the fabrication of a dualligand metal-organic framework (MOF) bio-MOF-1-coated stainless steel fiber via an in situ growth approach for SPME of six PAHs in water samples. Such MOF-based SPME in combination with gas chromatography (GC) gave enhancement factors of 3104-5980, ranges of 10-100 mu g L-1 for Nap, Ace, and Fle, 2.5-100 mu g L-1 for Phen, 0.1-100 mu g L-1 for FluA and Pyr, detection limits (S/N = 3) of 0.02-5.57 mg L-1, and quantitation limits (S/N = 10) of 0.14-17.2 mu g L-1 for the studied PAHs. The recoveries obtained by spiking 10 mu g L-1 PAHs in water samples ranged from 80% to 115%. The results showed that p-p interaction with biphenyldicarboxylate and pi-complexation between aromatic rings and the pyrimidine in the pores of bio-MOF-1 play significant roles in the extraction of PAHs.