Application of 3D structure of carbon nanotube-interwoven metal–organic frameworks in solid-phase microextraction of trace polychlorinated biphenyls from tea beverages

A three-dimensional (3D) structure of multiwalled carbon nanotubes (MWCNTs) interwoven metal–organic frameworks (MOFs) was synthesized. The MWCNTs was utilized to bridge the neighboring MOF nanocrystals. The hybrid material MOFs/MWCNTs was used for SPME coating to extract six PCB_S in tea beverages samples by gas chromatography coupled to tandem mass spectrometry. MOFs/MWCNTs coating materials were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and N₂ adsorption–desorption analysis. The response surface method was utilized to systematically optimize the main extraction factors. Under the optimized conditions, the developed method demonstrated wide linear ranges (0.01–1000 ng·L⁻¹), low limits of detection (0.003–0.009 ng·L⁻¹) and high enrichment factors (701–2361) for extracting and determining six PCB_S. The six PCB_S concentration in environmental tea beverages samples was detected with this method. These results display that MOFs/MWCNTs hybrid materials are potential sorbents in the SPME of PCB_S in environmental tea beverages samples.