PDMS-coated γCD-MOF solid-phase microextraction fiber for BTEX analysis with boosted performances

Owing to the ubiquitous occurrence and chemotoxicity of BTEX (benzene, toluene, ethylbenzene and xylene), the development of stable and accurate analysis methods that can assess environment risks and can generate monitoring data rapidly is urgent. In this work, a new strategy was proposed for efficient detection of BTEX. By creatively utilizing thermal deposition method, a robust SPME fiber was fabricated, where the gamma CD-MOF acted as the adsorbent, while PDMS functionalized as the adhesive and protective coating. Benefiting from the protection of PDMS, the gamma CD-MOF fiber presented significantly better extraction performance and exhibited long-term structural stabilities in aqueous or methanol samples up to a week. The stable and improved properties of gamma CD-MOF demonstrated that the PDMS protected the MOF components from the adverse effects of solvent. The detection limits of PDMS modified gamma CD-MOF fiber for BTEX was as low as 0.13-0.29 ng L-1 that accompanied with wide linear range of 1-1000 ng L-1, which was significantly superior to commercial PDMS fiber and other MOF-based fibers. Besides, the feasibility of the proposed method was verified by the quantitative determination of BTEX in real water samples. This work presents an effective strategy for creating ultrasensitive and stable SPME fibers based on gamma CD-MOF for applications in aqueous samples or other poor solvent. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Due to the widespread occurrence and toxicity of BTEX compounds, it is urgent to develop stable and accurate analysis methods for assessing environmental risks. In this study, a new strategy for efficient detection of BTEX was proposed using a thermal deposition method to fabricate a robust SPME fiber. The fiber, composed of gamma CD-MOF as the adsorbent and PDMS as the adhesive and protective coating, exhibited significantly improved extraction performance and long-term structural stability. The detection limits of the fiber for BTEX were as low as 0.13-0.29 ng L-1, with a wide linear range of 1-1000 ng L-1.