title: Development of dispersive liquid-liquid microextraction technique using ternary solvents mixture followed by heating for the rapid and sensitive analysis of phthalate esters and di(2-ethylhexyl) adipate.
abstract: In this study, for the first time, a dispersive liquid-liquid microextraction technique using a ternary solvent mixture is reported. In order to extract five phthalate esters and di(2-ethylhexyl) adipate with different polarities from aqueous samples, a simplex centroid experimental design method was used to select an optimal mixture of ternary solvents prior to gas chromatographyflame ionization detection. In this work, dimethyl formamide as a disperser solvent containing dichloromethane, chloroform, and carbon tetrachloride as a ternary extraction solvent mixture is injected into sample solution and a cloudy solution is formed. After centrifuging, 250μL of the obtained sedimented phase was transferred into another tube and 5μL DMF was added to it. Then, the tube was heated in a water bath at 75°C for 5min in order to evaporate the main portion of the extraction solvents. Finally, 2μL of the remained phase is injected into the separation system. Under the optimum extraction conditions, the method shows wide linear ranges and low limits of detection and quantification between 0.03-0.15 and 0.09-0.55μgL(-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 mineral water, soda, lemon juice, vinegar, dough, and yogurt packed in plastic packages.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran. Electronic address: mafarajzadeh@yahoo.com.
authors.forename: Mir Ali
authors.initials: MA
authors.lastname: Farajzadeh
authors.affiliation: Department of Chemistry, Faculty of Sciences, Azarbaijan Shahid Madani University, Tabriz, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Khoshmaram
mesh_terms: D000272:Adipates / Q000032:analysis*; D002725:Chloroform; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis; D004952:Esters / Q000032:analysis*; D006361:Heating; D059627:Liquid Phase Microextraction; D010795:Phthalic Acids / Q000032:analysis; D012680:Sensitivity and Specificity; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000032:analysis
chemical_list: D000272:Adipates; D004785:Environmental Pollutants; D004952:Esters; D010795:Phthalic Acids; D012997:Solvents; D014867:Water; C032279:phthalic acid; C029900:adipic acid; D002725:Chloroform
keywords: Dispersive liquid–liquid microextraction; Gas chromatography; Phthalate esters; Simplex centroid experimental design; Ternary solvents mixture