A novel sonication assisted dispersive liquid-liquid microextraction method for methylparaben in cosmetic samples using deep eutectic solvent

Abstract

A simple, green and sensitive analytical methodology for extraction and determination of methylparaben (MP) in cosmetic samples, based on deep eutectic solvent-based sonication assisted dispersive liquid-liquid microextraction (DES-SA-DLLME) combined with UV–Vis spectrophotometry was optimized by using a central composite design (CCD). Herein, we prepared and tested six DES (as extraction solvent) for the selective extraction of MP. A mixture of 525 μL of DES-3 (consisting of a 1:2:3 M ratio mixture of proline, malic acid and water, respectively) and 390 μL THF (aprotic solvent) was used for the DES-SA-DLLME process. Under optimum conditions based on the CCD, the calibration graph showed high level of coefficient determination (R2:0.9978) for the MP in the range of 15–650 μg L−1. The limit of detection and enrichment factor were 4.5 μg L−1 and 148, respectively. The application of the DES-SA-DLLME method was investigated for the extraction and quantification of MP in selected cosmetic samples in micrograms per liter and quantitative analytical data were obtained (RSDs <3.8%). This method provides quantitative recoveries, less extraction time, and uses green solvents for the determination of trace MP in complex matrices.