Spectrophotometric Determination of Curcumin after Preconcentration by Ultrasonic Assisted Supramolecular Dispersive Liquid-liquid Microextraction based on Solidification of Floating Organic Drops using Taguchi Design Method

Abstract

In this paper, the Taguchi orthogonal design was applied to optimize the extraction efficiencies for the determination of curcumin, after the separation and preconcenteration by supramolecular based-ultrasonic assisted-dispersion solidification liquid-liquid microextraction (SM-UA-DSLLME) procedure coupled with spectrophotometric UV-Vis. The experimental design consisted of six parameters (pH, amount of the extraction and disperser solvents, salt effect, sonication time and centrifuge time), each at five levels. The preconcentration method is based on the dispersion-solidification liquid-liquid microextraction of curcumin with decanoic acid/THF as the supramolecular solvent (a nano-structured liquid occurring on two scales, molecular and nano). The purpose method had two linear ranges of 0.01–0.40 and 0.40-3.50 mg L−1 of curcumin with R2= 0.9922 and 0.9799, respectively. The enrichment factors of 478.48 and 118.80 were obtained for down and up linear ranges, respectively. The preconcentration factor under consideration recovery was obtained 46. Detection limit was 5.2 µg L−1 and the relative standard deviation (RSD%), for eight replicate measurements of 0.2 mg L−1 curcumin was 2.47%. The results obtained from the analysis of variance (ANOVA), revealed that the most important effectible parameters onextraction curcumin are volume of disperser solvent and pH. The applicability of method was successfully applied to determine of trace curcumin in tablet, sewage and water samples.