Mesoporous Silica with Covalently Immobilized Anthracene as Adsorbent for SPE Recovery of PAHs Pollutants from Highly Lipidic Solutions

Two samples of functionalized mesoporous silica containing anchored anthrylmethylamine groups (SiO₂-Ant) have been prepared by surface assembling (1) and one step silane immobilization (2). Both adsorbents can be attributed to bimodal balanced hydrophobic-hydrophilic adsorbents with loading of anthracene groups about 15-33%. The adsorbents have been used for SPE of anthracene from organic solvents (acetonitrile, acetone and heptane) and model solutions of lipids (myristic acid and vegetable oil). The obtained results were compared with commercial C18 SPE cartridge. While C18 cartridge recovers anthracene from water-containing media (acetonitrile/water, 1/1), SiO₂-Ant cartridges much more efficient in extraction of anthracene from non-polar solvent (heptane). Lipids macrocomponents such as myristic acid and vegetable oil do not decrease the dynamic adsorption capacity and recovery of the model PAH on SiO₂-Ant. It was demonstrated that π-π stacking interaction with the analyte determine the selectivity of SiO₂-Ant towards of anthracene. This makes SiO₂-Ant attractive for selective pre-concentration of PAHs from high lipid content objects, such as vegetable oils.