Green effervescence assisted dispersive liquid–liquid microextraction based on a hydrophobic deep eutectic solvent for determination of Sunset Yellow and Brilliant Blue FCF in food samples

Abstract

In this study, a simple, fast and sensitive method called effervescence assisted dispersive liquid–liquid microextraction based on a hydrophobic deep eutectic solvent (EADLLME-DES) was used to extract synthetic dyes from food samples. This extraction technique makes use of hydrophobic DES as a green extraction solvent in acetic acid. This mixture was injected into a bicarbonate fortified sample, and as a result of the effervescence reaction, CO₂ bubbles were produced to facilitate dispersion of the extraction solvent. After the phase separation, the DES rich upper phase was diluted with methanol, and the absorbances at 485 and 635 nm for Sunset Yellow (SY) and Brilliant Blue FCF (BB), respectively, were measured. This method has linear calibration curves in the range of 0.005–3.5 μg mL⁻¹ for SY and 0.003–2.5 μg mL⁻¹ for BB under optimal conditions. Limits of detection (LOD) of 0.0029 and 0.0020 μg mL⁻¹ were obtained for SY and BB, respectively. This procedure was successfully applied for the determination of synthetic dyes in various real food samples.