Centrifugeless dispersive liquid-liquid microextraction based on salting-out phenomenon followed by high performance liquid chromatography for determination of Sudan dyes in different species

• Published in: Food chemistry Vol. 244; pp. 1 - 6
• Main Authors: Bazregar, Mohammad, Rajabi, Maryam, Yamini, Yadollah, Arghavani-Beydokhti, Somayeh, Asghari, Alireza
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-04-2018
• Subjects: Azo Compounds - analysis; Centrifugation; Chromatography, High Pressure Liquid - methods; Coloring Agents - analysis; Dispersive liquid-liquid microextraction; Food Analysis; Hydrogen-Ion Concentration; Limit of Detection; Liquid Phase Microextraction - methods; Naphthols - analysis; Salting-out phenomenon; Sodium Chloride - chemistry; Solidification of floating organic droplets; Sudan dyes; Time Factors; Water - analysis; Tetradecane (PubChem CID: 12389); Sudan I (PubChem CID: 5858445); Sudan red G (PubChem CID: 5359588); 1-Dodecanol (PubChem CID: 8193); Solidification of floating organic droplets; Sudan II (PubChem CID: 5809936); Sudan III (PubChem CID: 5379348); Acetonitrile (PubChem CID: 6342); Salting-out phenomenon; Sudan orange G (PubChem CID: 5359675); Dispersive liquid-liquid microextraction; Sudan dyes; Sudan IV (PubChem CID: 5876571); 1-Undecanol (PubChem CID: 8184)
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2017.10.006

•A centrifugeless dispersive liquid-liquid microextraction (DLLME) was introduced.•The method was applied for determination of six Sudan dyes.•The method is environmentally friendly, and is performed in just about 7 min.•The developed method is simple, fast, and sensitive.
In this work, a novel method, namely centrifugeless dispersive liquid-liquid microextraction, is introduced for the efficient extraction of banned Sudan dyes from foodstuff and water samples. In this method, which is based upon the salting-out phenomenon, in order to accelerate the extraction process, the extraction solvent (1-undecanol, 75 μL) is dispersed into the sample solution. Then the mixture is passed through a small column filled with 5 g sodium chloride, used as a separating reagent. In this condition, fine droplets of the extraction solvent are floated on the mixture, and the phase separation is simply achieved. This method is environmentally friendly, simple, and very fast, so that the overall extraction time is only 7 min. Under the optimal experimental conditions, the preconcentration factors in the range of 90–121 were obtained for the analytes. Also good linearities were obtained in the range of 2.5–1200 ng mL−1 (r2 ≥ 0.993).