Liquid-liquid microextraction of synthetic pigments in beverages using a hydrophobic deep eutectic solvent

- Four hydrophobic deep eutectic solvent (DES) prepared.
- Hydrophobic DES was used in liquid-liquid microextraction of eight synthetic pigments.
- The method was set up for the analysis of eight synthetic pigments in beverages.

A method was developed for the determination of eight synthetic pigments in beverage samples by liquid-liquid microextraction followed by high performance liquid chromatography. Using hydrophobic deep eutectic solvent (DES) as the microextraction solvent, several key parameters were optimized, including the type and volume of the hydrophobic DES, pH value, vortex time and salt content. Detection limits were in the range 0.016-1.12 ng/mL, recoveries were in the range 74.5-102.5% and relative standard deviations were <5.4%. The method is simple, green and practical, and could be applied to the extraction and determination of synthetic pigments in beverages.