Rapid spectrophotometric determination of trace amounts of azorubine dye in food samples after dispersive liquid-liquid microextraction

摘要

A novel dispersive liquid-liquid microextraction method for the determination of azorubine by spectrophotometry has been developed. Azorubine is an anionic azo dye that was used in food industrial in some country. The method is based on the liquid-liquid microextraction of azorubine from aqueous solution using chloroform as extraction solvent and cetyltrimethylammonium bromide (CTAB) as disperser and also as a cation for neutralization of azorubine. The effects of different parameters such as pH, type of extraction solvent, concentration of surfactant as dispersive solvent and time on the dispersive liquid-liquid microextraction of dye were investigated and optimum conditions were established. Under the optimum conditions the calibration graph was linear in the rage of 10-1200 ppb with detection limit of 3 ppb. The relative standard deviation (RSD) for 50 and 1000 were 3.9 and 1.8% (n = 8), respectively. The method was applied to the determination of the azorubine dye in different food samples.