Utilization of water-contained surfactant-based ultrasound-assisted microextraction followed by liquid chromatography for determination of polycyclic aromatic hydrocarbons and benzene in commercial oil sample

In this work, a microextraction method, water-contained surfactant-based ultrasound-assisted, followed by high-performance liquid chromatography (HPLC) was developed for determination of five polycyclic aromatic hydrocarbons (PAHs) and benzene in commercial oil samples. During the microextraction method, a micellar solution as the only extraction solvent was injected into the oil sample in a conical bottom glass tube and formed a cloudy solution. The dispersion process was accelerated by applying ultrasound irradiation. Phase separation was done by centrifugation and then the lower sediment phase was directly analyzed by HPLC. A chemometrics approach was applied for the optimization of the extraction condition. Under the optimum conditions, the proposed method showed good linearity within the different ranges for different analytes (e.g., 0.10–200 ng mL−1 for phenanthrene), the square of the correlation coefficient was higher than 0.999 and the appropriate limit of detection was in the range of 0.04–0.41 ng mL−1. The recoveries in all cases were above 95 %.