High‐throughput microscale extraction using ionic liquids and derivatives: A review

Abstract

Ionic liquids and derivatives-mainly polymeric ionic liquids and magnetic ionic liquids-have been extensively used in microscale extraction over the past few years. Current trends in analytical sample preparation gear toward linking microextraction approaches with high-throughput sample processing to comply with green analytical chemistry requirements. A variety of high sample throughput strategies that are coupled to both ionic-liquid-based solid-phase microextraction and ionic liquid-based liquid-phase microextraction are herein reported. The review is focused on microscale extraction methods that use (i) custom-made and dedicated extraction devices, (ii) parallel extraction, (iii) magnetic-based separation, and (iv) miniaturized systems employing semi-automatic or fully automatic flow injection methods, related micro/millifluidic devices, and robotic equipment. K E Y W O R D S automation, ionic liquids, magnetic ionic liquids, polymeric ionic liquids, sample preparation Article Related Abbreviations: γ-MAPS, 3-(trimethoxysilyl) propylmethacrylate; μ-SPE, micro-solid phase extraction; [(AC 3 )MIM + ], 1-aminopropyl-3-methylimidazolium; [(VIM) 2 C 10 2+ ], 1,12-di(vinylimidazolium)decane; [(VIM) 2 C 6

Novel materials as capillary coatings for in‐tube solid‐phase microextraction for bioanalysis

“…These compounds are an intriguing class of molten salts and possess tunable physicochemical properties [64]. Incorporation of functional groups of different polarity into the IL structure might promote distinct interactions with the solutes and even allow high solvation capabilities for both polar and nonpolar compounds [65]. Among the many subclasses of ILs, polymeric ILs exhibit adequate chemical and mechanical stability for application as sorbent phase in the in-tube SPME technique.…”

Determination of bisphenol A: Old problem, recent creative solutions based on novel materials

“…ILs are non-molecular solvents composed of organic or inorganic ions, with melting point <100 • C [132]. Since their discovery in 1914 they have been very useful and important tools for different advances in chemistry [133].…”

“…Generally, ILs can also be characterized by their high thermal stability and conductivity, while properties such as viscosity, hydrophobicity and selectivity are tuned due to the composition of cation and anion [132,135]. This tunability is one of the main advantages of these materials, since they can be developed and applied according to the goal of the application [134,135].…”

“…This characteristic can be very useful in sample preparation, since phase separation can be performed with the aid of a magnet [133][134][135]. Polymeric ionic liquids (PILs) are another IL derivative produced commonly by the polymerization of IL monomers, but other strategies are possible such as Radziszewski reaction [132,139,140]. PILs show some of the characteristics of ILs, but due to the formation of polymer chains, possess greater thermal stability, durability, mechanical robustness, and longer lifetime [139].…”

An overview of magnetic ionic liquids: From synthetic strategies to applications in microextraction techniques

“…Furthermore, ILs have been examined as "greener" extraction phases in microextraction techniques consisting of safer alternatives compared to organic solvents typically employed. Another interesting feature consists of numerous possibilities of tailoring the chemical structure in order to modify their physicochemical properties and extraction selectivity [7,8].…”