Development of a MIL–101 Cr (NH2)@SiO2@NiFe2O4 nanoparticles based magnetic solid phase extraction method and its application in extraction of perfluorooctanoic acid and perfluorooctane sulfonate from honey

In the present research, a MIL–101 Cr (NH₂)@SiO₂@NiFe₂O₄ nanoparticles based magnetic solid phase extraction conducted in a narrow bore tube has been developed and validated for extraction of perfluorooctanoic acid and perfluorooctane sulfonate from honey samples. For this purpose, an extraction vessel was designed and honey sample solution was transferred into it. After that, the synthesized magnetic sorbent was added and placed at the bottom of the tube. After a few minutes, the stopcock of the extraction vessel was opened and the sample was passed through in the presence of a magnet. In the subsequent step, the magnetic particles were rinsed with a suitable deep eutectic solvent using vortex agitation. At the end, the eluent phase was taken and analysed using high performance liquid chromatography–tandem mass spectrometry. Under the best conditions, the validation of suggested procedure was done and based on the outcomes, great precision (relative standard deviations ≤ 6.0 %), good linearity (r² ≥ 0.9978) in a wide concentration range, low limits of detection (20 and 23 ng kg^–1 for perfluorooctanoic acid and perfluorooctane sulfonate, respectively) and quantification (67 and 77 ng kg^–1 for perfluorooctanoic acid and perfluorooctane sulfonate, respectively), and acceptable extraction recoveries (80 and 74 % for perfluorooctanoic acid and perfluorooctane sulfonate, respectively) were acquired. In the following, the presented method was effectively employed for quantification of perfluorooctanoic acid and perfluorooctane sulfonate in twenty honey samples and based on the outcomes they were free of the mentioned pollutants.