Magnetic solid phase extraction of N- and S-containing polycyclic aromatic hydrocarbons at ppb levels by using a zerovalent iron nanoscale material modified with a metal organic framework of type Fe@MOF-5, and their determination by HPLC

Metal organic frameworks of type MOF-5 exhibit good adsorption capacity for many organic compounds. The authors have used nanoscale silica-coated zerovalent iron and MOF-5 to prepare, by co-precipitation, a novel magnetic nanomaterial of type Fe@MOF-5. Its morphology and structure were characterized by transmission electron microscopy and X-ray diffraction. The nanomaterial is shown to be well suited for magnetic solid phase extraction for five kinds of N- and S-containing polycyclic aromatic hydrocarbons prior to quantitation by HPLC. The limits of detection are in the 25 to 33 ng⋅L concentration range. Four real water samples were used to validate the method, and the recoveries of spiked samples with concentrations of 5 and 10 ppb were found to be in the range between 92.6 and 97.3% (n = 3). The Fe@MOF-5 sorbent obviously has excellent adsorption capability for such compounds, can be fairly easily synthesized, displays sensitivity, simplicity, ease of operation, and can be prepared at low costs. In our perception, it has a large potential in terms of monitoring such environmental pollutants. [Figure not available: see fulltext.]