A solid phase microextraction Arrow with zirconium metal-organic framework/molybdenum disulfide coating coupled with gas chromatography-mass spectrometer for the determination of polycyclic aromatic hydrocarbons in fish samples.

Solid phase microextraction (SPME) Arrows with enlarged sorption phases and Arrow-shaped tips are good alternatives to classic SPME fibers. Developing SPME Arrows with functionalized coatings has become a growing area of SPME research. In this study, a zirconium metal organic framework/molybdenum disulfide (UiO-66/MoS2 ) composite coating modified SPME Arrow was developed and coupled with gas chromatography-mass spectrometry for the headspace extraction and detection of 16 polycyclic aromatic hydrocarbons (PAHs). The coating preparation can be easily manipulated by the assembly strategy using silicone gels to adhere UiO-66/MoS2 powder onto the surface of the Arrows. The prepared UiO-66/MoS2 coated SPME Arrows exhibited clearly enhanced adsorption capacity (2.1-4.5 folds) and an improved degree of affinity to PAHs species when compared to commercial PDMS/CARS/DVB SPME Arrows or fibers. The improved mechanism may be due to the high specific area, hierarchical micropores and mesopores, and the largely increased and immobilized amount of UiO-66/MoS2 coating on the stainless-steel Arrow. Under optimized conditions, the SPME Arrow-based assay was successfully applied to determine PAH levels in fish samples with satisfactory recoveries of 80.2-101% and relative standard deviations (RSDs) of less than 6%. The detection limits of PAHs were between 0.11-1.40 ng kg-1 . The coating showed satisfied reproducibility and repeatability (RSD <8.6%) with only 10 mL of 10% (v/v) acetone in water used as the extraction phase in an effort to be environmentally friendly. All of the results showed that the method is simple, sensitive, and robust. SPME Arrows with UiO-66/MoS2 coatings can provide new opportunities for the efficient extraction of persistent organic pollutants in food safety applications.