An octahedral magnetic metal organic frameworks for efficient extraction and enrichment of six pesticides with benzene ring prior to high performance liquid chromatography analysis

In this work, an octahedral magnetic metal organic frameworks composed of Fe3O4@NH2-MIL-101 was synthesized through simple solvothermal reaction for magnetic solid phase extraction (MSPE) of six pesticides with benzene ring in environmental water samples. The Fe3O4@NH2-MIL-101 was characterized by various techniques. The results showed Fe3O4@NH2-MIL-101 exhibits ultra-high surface area (1012.7 m2 g−1), large pore volume (0.64 cm3 g−1) and high magnetic responsivity (30.0 emu g−1), which can be used as an ideal adsorbent for rapid isolation and enrichment of target analytes. A sensitive method was developed by using Fe3O4@NH2-MIL-101-based MSPE coupled with HPLC (High performance liquid chromatography) with UV (Ultraviolate) detector. The linear range extended to 1000 µg L−1 was achieved, low limits of detection (S/N = 3) of 0.13–0.86 µg L−1 and good reproducibility (1.8–3.1%). The applicability of Fe3O4@NH2-MIL-101 was demonstrated for determining six pesticides in water samples with satisfactory recoveries at two spiking levels of 20.0, 80.0 µg L−1 were in the range of 70.5 to 119.8% with the RSDs less than 8.1%. These accurate experimental results by this method indicated that the novel Fe3O4@NH2-MIL-101 as a MSPE adsorbent was an attractive option for efficient extraction and enrichment trace pesticides in future.