Recent advances in dispersion strategies for dispersive liquid-liquid microextraction from green chemistry perspectives

It has been a long time since dispersive liquid-liquid microextraction (DLLME) was first introduced in 2006 as an efficient sample preparation technique. However, it is still grabbing the attention of researchers for making it more efficient, accessible, miniaturized, and environmentally friendly. The crucial stage in DLLME is the dispersion of extraction solvent in aqueous samples which is usually achieved by means of dispersive solvents. Due to the considerable environmental risk posed by the hazardous dispersive solvents, efforts have been made to develop greener dispersion techniques while preserving high extraction efficiency. The number of intriguing methods for replacing disperser solvents had increased when it comes to standard DLLME. Therefore, the aim of this review is to give a summary of the current trends in the recent dispersion strategies of DLLME. Different strategies, including the use of green dispersers in addition to physical and chemical dispersion approaches, are discussed. The most remarkable strategies that have been applied and published up to this point are emphasized. Finally, the challenges and perspectives for these approaches' future are highlighted. The review could suggest new research directions, strengthen support for existing theories and identify patterns among existing research studies concerned with DLLME.