Vortex assisted deep eutectic solvent (DES)-emulsification liquid-liquid microextraction of trace curcumin in food and herbal tea samples.

We developed a new microextraction method for separation and preconcentration of curcumin using deep eutectic solvent known as green solvent. Deep eutectic solvent (DES) formed by mixing of choline chloride and phenol was used as an extraction solvent in microextraction study to extract the curcumin at pH 4.0. The curcumin concentration in enriched DES phase was analyzed by UV-Visible spectrophotometer. The effect of parameters such as pH, mol ratio of DES composition, volume of DES, volume of tetrahydrofuran (THF) and sample volume were examined. Interference effects of matrix components were investigated. The preconcentration factor was 12.5. The detection limit of method (n = 10) was 2.86 µg L-1 and the relative standard deviation (RSD, n = 8) was 1.8%. The method was successfully applied to determination of curcumin in food and herbal tea samples. The mean recoveries were between 96% and 102% and standard deviations were found in the range of 1-6%.