Feasible Emulsive Liquid–Liquid Microextraction Using Solidification of Floating Organic Droplets for Spectrophotometric Determination of Curcumin
摘要
A novel approach for extracting curcumin was introduced, which integrates the advantages of microextraction with emulsive liquid–liquid and solidification of floating organic droplets processes. The extraction solvent, 1-undecanol, and deionized water, were mixed to generate an emulsion prior to their rapid injection into the sample solution. To improve the phase separation, centrifugation was used. The target analyte-containing organic drops that floated were then collected for analysis of curcumin after they solidified by cooling. The experimental variables that influence the extraction performance were explored and adjusted. Quantitative extraction was attained at pH 7.0 utilizing 100 μL of 1-undecanol as extraction solvent emulsified in 400 μL of deionized water, with the addition of 0.3 mol L−1 NaCl. The procedure is selective in the presence of concomitant ions and dyes. The procedure exhibits linearity up to 2000 μg L−1, with an enrichment factor of 19.8 for 10.0 mL sample. The detection and quantification limits were 1.6 μg L−1 and 4.8 μg L−1, respectively. The inter-day and intra-day precision varied between 1.7 and 2.6%. Ultimately, the developed approach succeeded in quantifying curcumin at a trace level in herbal tea and spice samples, with a recovery rate ranging from 95.0 to 101.0%.
Graphical Abstract