Application of magnetic material in the determination of polycyclic aromatic hydrocarbons in tree leaves by high performance liquid chromatography

Carbon coated Fe(3)O(4) magnetic particles (Fe(3)O(4)/C) were synthesized by hydrothermal reaction, and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and transmission electron microscopy (TEM). The material is applied to microwave-assisted extraction for clean-up and enrichment of polycyclic aromatic hydrocarbons (PAHs) from tree leaves. Magnetic solid-phase extraction (MSPE) parameters including elution solvents, amount of sorbents and enrichment time are optimized together with microwave extraction time, power, extraction solvents and the ratio of liquid to solid. Under the optimal conditions, the developed method provides spiked recoveries of 77.7-103.8% with RSDs of less than 4.0%, and limits of detection (LOD) of 0.5-2.0 ng g(-1). PAHs in tree leaves are successfully determined.