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

• Published in: Journal of Chromatography A Vol. 1379; pp. 24 - 33
• Main Authors: Farajzadeh, Mir Ali, Khoshmaram, Leila
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 30.01.2015
• Subjects: Adipates - analysis; Chloroform; Dispersive liquid–liquid microextraction; Dough; Environmental Monitoring - methods; Environmental Pollutants - analysis; Esters; Esters - analysis; Gas chromatography; Heating; Ionization; Liquid Phase Microextraction; Liquid-liquid extraction; Optimization; Phthalate esters; Phthalates; Phthalic Acids - analysis; Sensitivity and Specificity; Simplex centroid experimental design; Solvents; Solvents - chemistry; Ternary solvents mixture; Tubes; Water - analysis; Gas chromatography; Simplex centroid experimental design; Phthalate esters; Ternary solvents mixture; Dispersive liquid–liquid microextraction
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2014.12.049

•A DLLME technique using a ternary solvent mixture was developed for the first time.•Simplex centroid experimental design was used in the selection of extraction solvents mixture.•Three solvents with different polarities including CH2Cl2, CH3Cl and CCl4 were used.•The method has high EFs (980–4500) and low LODs (0.03–0.15μgL−1) for all analytes. 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.