Supramolecular-based dispersive liquid-liquid microextraction: a novel sample preparation technique utilizes...

The present study reports a novel sample enrichment method termed supramolecular-based dispersive liquid-liquid microextraction (SM-DLLME). The SM solvent selected was made up of reversed micelles of decanoic acid dispersed in tetrahydrofuran (THF)-water. THF plays double role, not only acts as a disperser solvent but also causes self-assembly of decanoic acid. The contaminant used as a model was Malachite Green (MG). It was a cationic dye and was preconcentrated without any derivatization or ion-pair formation reaction. In SM-DLLME, the most important advantages of DLLME technique and preconcentration strategy based on the coacervation and reverse micelles have come together. Moreover, in this method, disadvantages of DLLME such as extraction capability of only hydrophobic analytes and hiring toxic and hazardous organic solvents as the extraction solvent and disadvantages of coacervation-based extraction method such as tedious, labor-intensive and time-consuming stirring procedure have been avoided. Several variables affecting the microextraction efficiency were investigated and optimized. Under the optimized conditions and preconcentration of only 5.00 mL of sample, the enhancement factor was 52, limit of detection (LOD) was 4 μg/L and relative standard deviations (RSDs) for 145 and 36 μg/L of MG in textile industry wastewater were 1.8 and 3.2%, respectively (n = 6).