Ionic Liquids in the Microextraction Context

The structural versatility of ionic liquids (ILs), the wide range of interest properties that can present: low to negligible vapor pressure, from water-soluble to water-insoluble, from medium viscosity to high viscosity…, their synthetic tuneability, together with their impressive solvation abilities for analytes of quite different nature, make their use in microextraction techniques an obvious approach of great interest.

Thus, ILs and a group of interesting derivatives, such as polymeric ionic liquids (PILs) and IL-based surfactants, pure, mixed, or combined with other materials forming hybrid sorbents, have been used in all variants of liquid-phase and solid-based microextraction strategies.

This chapter will give an exhaustive overview of existing approaches that combine ILs and derivatives in liquid-phase microextraction (LPME) modes such as single-drop microextraction (SDME), hollow fiber liquid-phase microextraction (HF-LPME) and dispersive liquid-liquid microextraction (DLLME), including all their variants; and also in solid-based microextraction methods, such as micro-solid-phase extraction (μ-SPE), solid-phase microextraction (SPME), stir-bar sorptive extraction (SBSE), and stir-cake sorptive extraction (SCSE).

Keywords: Dispersive liquid-liquid microextraction, Environmental applications, Food applications, Hollow-fiber liquid phase-microextraction, Ionic liquids, Ionic liquid-based surfactants, Liquid-phase microextraction, Micro-solid-phase extraction, Polymeric ionic liquids, Single-drop microextraction, Solid-phase extraction, Solid-phase microextraction, Stir-bar sorptive extraction, Stir-cake sorptive extraction.