Different approaches to the solid-phase extraction of pollutants from water and food products

Control of the presence of various organic pollutants in agricultural products is one of the major issues preoccupying the regulatory agencies and industrial laboratories worldwide. The pesticides, produced by the agricultural sector, are regarded as one of the most hazardous contaminants found in the environment. They are not only toxic but also mobile and capable of bioaccumulation. Nowadays, pesticides are found in surface waters and in a growing number of aquifers, thus even if present at low concentration levels constituting a potential risk for ecosystems, drinking water quality and human health. Due to the low concentration of analytes, the complexity of some sample matrices and incompatibility of sample medium with analytical instrument a preliminary sample pre-concentration and/or separation is required. Magnetic nanoparticles have attracted significant attention because of their strong magnetic response combined with easily regulated properties via the surface modification. In this communication we report a new approach for preparation of magnetic nanoadsorbent with covalently grafted non-ionic Triton X-100 surfactant. Mesoporous Triton X-100-immobilized (Fe3O4@Triton) magnetic nanoparticles were successfully synthesized by core-shell technology and characterized using transmission electron microscopy, X-ray diffractional analysis, nitrogen physisortpion, energy-dispersive X-ray elemental analysis, vibrating sample magnetometry. The produced Fe3O4@Triton solid was employed as an adsorbent for the pre-concentration of pesticides present in water and food products before analyzing them by gas chromatography coupled with mass spectrometry GC-MS technique. The variables affecting the performance of the adsorbent in the both extraction steps such as type and volume of eluent and extraction solvent, breakthrough volume, salt addition, extraction time were thoroughly investigated. The proposed method resulted in good linearities (R2 > 0.9915) in the range of 1–10