مشخصات پژوهش

tIn this study, for the first time, a dispersive liquid–liquid microextraction technique using a ternarysolvent mixture is reported. In order to extract five phthalate esters and di(2-ethylhexyl) adipate withdifferent polarities from aqueous samples, a simplex centroid experimental design method was used toselect an optimal mixture of ternary solvents prior to gas chromatographyflame ionization detection.In this work, dimethyl formamide as a disperser solvent containing dichloromethane, chloroform, andcarbon tetrachloride as a ternary extraction solvent mixture is injected into sample solution and a cloudysolution is formed. After centrifuging, 250 L of the obtained sedimented phase was transferred intoanother tube and 5 L DMF was added to it. Then, the tube was heated in a water bath at 75◦C for 5 minin order to evaporate the main portion of the extraction solvents. Finally, 2 L of the remained phase isinjected into the separation system. Under the optimum extraction conditions, the method shows widelinear ranges and low limits of detection and quantification between 0.03-0.15 and 0.09-0.55 g L−1,respectively. Enrichment factors and extraction recoveries are in the ranges of 980–4500 and 20–90%,respectively. The method is successfully applied in the determination of the target analytes in mineralwater, soda, lemon juice, vinegar, dough, and yogurt packed in plastic packages.