Ion-pair solvent-based liquid-liquid microextraction and spectrophotometric determination of E102, E110, E124, E129 and E133 in confectioneries and beverages

In the present study, a new ion-pair solvent including tetra-n-butyl-ammonium iodide and 1-pentanol was prepared for the first time and it was used for microextraction and UV-Vis spectrophotometric determination of tartrazine (E102), sunset yellow (E110), ponceau 4r (E124), allura red (E129) and brilliant blue (E133). Analytical parameters of the procedure such as pH, concentration of ion-pair solvent and its volume, times of vortex and centrifugation were optimized. Interference effect of matrix ions and dyes were investigated after optimization of the parameters. Limits of detection between 24 and 82 mu g L-1 and limits of quantification in the range of 80-275 mu g L-1 were determined for the examined dyes. Preconcentration factor was obtained as 15 for each of the dyes. Relative standard deviations were found between 3.2 and 6.1%. Linear dynamic ranges were obtained between 0.28 and 20 mu g mL(-1) for the determined dyes. Procedure was applied to various food samples including energy drinks, powdered juice samples, syrups and candies. Analyte addition-recovery studies were also performed both for validation of procedure and determination of dye concentrations in the real samples. Food dye contents of real samples were determined between 5.9 and 52.4 mu g mL(-1) for liquid samples and 6.2 and 135.2 mu g g(-1) for solid samples with satisfactory recovery results ranging from 93 to 103%. Finally, the greenness of the developed procedure was assessed using two tools, the Green Analytical Procedure Index and Analytical Eco-Scale.

Automated summary

In this study, a new ion-pair solvent was prepared for the first time and used for microextraction and UV-Vis spectrophotometric determination of several food dyes. The procedure was optimized for pH, ion-pair solvent concentration and volume, times of vortex and centrifugation. The developed procedure showed satisfactory results in terms of detection limits, preconcentration factor, and recovery rate.