A cadmium(II)-based metal-organic framework material for the dispersive solid-phase extraction of polybrominated diphenyl ethers in environmental water samples

In this study, a stable cadmium(II)-based metal-organic framework (MOF) material was designed and used as a sorbent for the dispersive solid-phase extraction (dSPE) of polybrominated diphenyl ethers (PBDEs) in environmental water samples. Gas chromatography coupled with triple quadrupole mass spectrometer (GC-MS/MS), working in the negative chemical ionization mode, was used to quantify the target analytes. Characterization of the material was performed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), elementary analyses (EA) and thermogravimetric analyses (TGA). The synthesized rod shape MOF is on the micro level in size and has excellent chemical and solvent stability. The extraction conditions, including the extraction time, temperature and ionic strength, were examined systematically using response surface methodology (RSM). Under optimized conditions, the method that was developed showed an excellent extraction performance. Good linearity (R2 > 0.99) within the concentration range of 0.25-250 ng L−1 was obtained. Low limits of detection (0.08-0.15 ng L−1, signal-to-noise ratio = 3:1) and good precision (relative standard deviation <12%, n = 6) were achieved. The developed method was applied to analyze natural and spiked environmental water samples.