Determination of polycyclic aromatic hydrocarbons in edible oil by magnetic solid phase extraction based on a mesoporous molybdenum disulfide/graphite prior to gas chromatography-mass spectrometry

In this work, a magnetic mesoporous molybdenum disulfide/graphite nanosheets (mm-MoS2/GN) was successfully synthesized and applied to magnetic solid phase extraction (MSPE) of 13 polycyclic aromatic hydrocarbons (PAHs) from edible oil samples. The prepared mm-MoS2/GN was characterized by FT-IR, XRD, VSM, BET, SEM and TEM. The influence of various parameters such as the adsorbent mass, adsorption/desorption time, and elution solvent through response surface methodology in MSPE was investigated. The porous and fluffy structure with rich active sites (π interactions, electrostatics, hydrogen bonds) and amphiphilicity properties of mm-MoS2/GN make it an ideal material for the separation and enrichment of trace PAHs in edible oils. Under optimal MSPE and GC-MS conditions, the linearity ranges of the proposed method were 1.0–100.0 μg·kg−1 with a satisfactory correlation coefficient above 0.9907. The limits of detection and quantification for 13 PAHs were 0.10–2.50 μg·kg−1 and 0.85–5.00 μg·kg−1, respectively. The intra- and inter-day precisions were less than 3.0 % and 3.6 %, respectively. The recoveries for spiked edible oil samples ranged from 70.2 % to 112.6 % with RSDs of less than 5.8 %. In this work, a novel, rapid, economic and effective method was proposed, and successfully applied to detect polycyclic aromatic hydrocarbons in several oil samples from local market.