Zeolite/Fe3O4 as a new sorbent in magnetic solid-phase extraction followed by gas chromatography for determining phthalates in aqueous samples.

In the present study, for the first time, we successfully employed zeolite/Fe3O4 as a new magnetic nanoparticle sorbent in magnetic solid-phase extraction for determining phthalates in aqueous samples. Gas chromatography with flame ionization detection was used to detect the target analytes as a powerful instrumental analysis. Affecting parameters in the extraction process, including the amount of adsorbent, adsorption and desorption time, and volume of desorption solvent, were optimized using a response surface methodology based on central composite design. Under the optimum conditions, the linear range for dibutyl phthalate and bis(2-ethylhexyl phthalate) was varied in the interval of 10-1700 and 10-1200 μg/L, respectively. Limits of detection were 2.80 μg/L for dibutyl phthalate and 3.20 μg/L for bis(2-ethylhexyl phthalate). The recovery value for the extraction of target analytes was between 97 and 111%. The repeatability and reproducibility of the new proposed method were obtained: 10-13% and 13-13.5%, respectively. The increased sensitivity in using the proposed method has been demonstrated. Compared with previous methods, the new proposed method is an accurate, rapid, and reliable sample-pretreatment method.