Phytic acid-stabilized super-amphiphilic Fe3O4-graphene oxide for extraction of polycyclic aromatic hydrocarbons from vegetable oils.

Phytic acid-stabilized Fe3O4-graphene oxide (GOPA@Fe3O4) was assembled by microwave-enhanced hydrothermal synthesis and super-amphipathicity was demonstrated by measurement of dynamic oil and water contact angles. GOPA@Fe3O4 was used as a sorbent for enrichment of eight polycyclic aromatic hydrocarbons (PAHs) from vegetable oils by magnetic solid-phase extraction (MSPE). The extraction-desorption factors were systematically investigated and, under optimum conditions, the super-amphiphilic sorbent achieved wide linear ranges (0.2-200ngg(-1)), satisfactory precision (3.44-6.64% for intra-day and 5.39-8.41% for inter-day) and low limits of detection (LODs, 0.06-0.15ngg(-1)) for PAHs. Excellent recoveries (85.6-102.3%) for spiked PAHs were obtained with genuine vegetable oil samples. These results indicate that MSPE using GOPA@Fe3O4 as the sorbent, coupled with high performance liquid chromatography (HPLC), is an efficient and simple method for the detection of low concentrations of PAHs in vegetable oils.