Green Analysis: A Review on Dispersive Liquid-Liquid microextraction

Old traditional Solvent extraction methods like solvent microextraction (SME), liquid-phase microextraction (LPME) may have been considered one of the interesting academic research topics. SME and LPME has become a powerful tool for environmental, food, clinical, pharmaceutical, and industrial research and development analysis. LPME basically consists of two major modes: Exposed solvent and protected solvent microextraction of liquid, solid, and gaseous samples. But, the major drawbacks to these techniques are relatively long extraction times and evaporation, dissolution, and instability. Dispersive liquid-liquid microextraction (DLLME), however, overcomes these problems and has resulted in an explosion of research and applications since from its introduction in 2006. DLLME involves the dispersal of an extraction solvent in a liquid sample, resulting in a large extraction solvent surface area and almost instantaneous extraction with nearly 100% analyte recovery. In the last decade the move toward more green solvents has led to the development of DLLME procedures using ionic liquids (ILs) and deep eutectic solvents (DESs). Dispersive liquid-liquid microextraction (DLLME) overcomes an old traditional solvent extraction method and brings the use of chemicals from litres to micro-litres (μL) and reduces wastage of solvents, enhance extraction efficiency.  DLLME technique is simple, rapid, inexpensive, effective, and environmentally friendly as it follows green chemistry principles. In this chapter our focus of this discussion is Dispersive liquid-liquid microextraction (DLLME) methods and Solvents used. In recent discussion, there are lists the more commonly used DLLME dispersion generation modes and methods. The advantages, disadvantages, and some recommendations for developing DLLME methods are covered in discussion.