A Simple Spectrophotometric Evaluation Method of Allura Red (E129) in Several Food Samples Using Cloud Point Extraction

Abstract

Cloud point extraction (CPE) method was successfully used for estimation and preconcentration of Allura red by spectrophotometry. The procedure was depended on the extraction of Allura red as an ion pair with cetylpyridinium chloride from aqueous solution using a nonionic surfactant TX-114 or Brij-35. The absorbance of the extracted surfactant-rich phase was measured at 507 nm after dilution with water. The influence of different factors on cloud point extraction (CPE) of Allura red such as pH media, equilibrium temperature, incubation time, concentration of surfactant and electrolyte concentration were investigated. Calibration curve was linear in a concentration range between 2-40 μgml-1 of Allura red with correlation coefficient r= 0.9998 for TX-114 and 0.9992 for Brij-35.The developed procedure was applied for estimation and preconcentration of Allura red in different food samples.

Keywords

Cloud point extraction, CPE method was successfully used for estimation and preconcentration of Allura red by spectrophotometry. The procedure was depended on the extraction of Allura red as an ion pair with cetylpyridinium chloride from aqueous solution using a nonionic surfactant TX-114 or Brij-35. The absorbance of the extracted surfactant-rich phase was measured at 507 nm after dilution with water. The influence of different factors on cloud point extraction, CPE of Allura red such as pH media, equilibrium temperature, incubation time, concentration of surfactant and electrolyte concentration were investigated. Calibration curve was linear in a concentration range between 2-40 μgml-1 of Allura red with correlation coefficient r= 0.9998 for TX-114 and 0.9992 for Brij-35.The developed procedure was applied for estimation and preconcentration of Allura red in different food samples.