Strengths and weaknesses of ionic liquids as efficiency enhancers in capillary electrophoresis

Ionic liquids (ILs) are well-recognized additives in the separation sciences. In particular, ILs are commonly used in capillary electrophoresis (CE), as their ability to influence the status of the silanol groups on the capillary surface makes them ideal for modifying the electroosmotic flow (EOF). In-teractions between cations and deprotonated silanol groups is a key element in this mechanism. Addi-tionally, the separation mechanism in CE can be changed via ionic and/or proton donor/acceptor interactions occurring between the ILs and analytes. These different types of interactions can modify the efficiency of the CE separation, hence establishing the role of ILs as efficiency enhancers. Given the growing number of ILs, their high variability, and their attractive physicochemical properties, it is critical to remain up-to-date on current trends in the applications of ILs in CE. Thus, this review assesses the strengths and weaknesses of the various applications of ILs in CE published between 2016 and 2022.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

This article discusses the applications of ionic liquids (ILs) in capillary electrophoresis (CE). ILs are used to modify the electroosmotic flow in CE by influencing the silanol groups on the capillary surface. The interactions between ILs and analytes can change the separation mechanism and efficiency of CE, making ILs important additives in CE.