Homogeneous Liquid-Liquid Microextraction Based on Deep Eutectic Solvents

Abstract

The improvement of the extraction techniques in accordance with the principles of green chemistry has accelerated significantly in recent years. Solvents have unique roles in green extraction techniques. A solvent must meet certain characteristics in order to be classified as a green medium, including low vapor pressure, low toxicity, biodegradability, and biocompatibility. Deep eutectic solvents (DESs) have attracted a lot of interest as a green alternative to the ionic liquids and organic solvents in different field especially in microextraction techniques. The history, properties, and synthesis procedure of DESs are briefly described herein. The majority part of this paper is devoted to reviewing the homogenous liquid-liquid microextraction methods (HLLME) based on DESs. The HLLME is one of the most popular microextraction techniques. The HLLME mods are classified in this work based on the phase separation stimulating factors including addition of a hydrophobic solvent, pH adjustment, temperature adjustment, and other new strategies.

Keywords: Deep eutectic solvents, Green analytical chemistry, Green solvents, Homogeneous liquid-liquid microextraction, Separation science