Analytical applications and physicochemical properties of ionic liquid-based hybrid materials: A review

Ionic liquids with their unique properties found so far numerous analytical applications. Among them ionic liquids immobilized on the surface or within the pores of a solid support were successfully utilized in extraction techniques dedicated to preconcentration of the analytes from food, environmental and biological samples. In this review we focus on comprehensive summarizing of available literature data on the examples of ionic liquid-based hybrid materials implementation in selected analytical extraction techniques, namely solid-phase extraction, solid-phase microextraction, hollow-fiber solid-phase microextraction, stir-bar sorptive extraction and biosensors. Additionally, this work is supported by concise discussion on strategies of ionic liquids immobilization in order to form hybrid materials (both chemical and physical) and the effects of confinement on structures along with ionic liquids physicochemical properties. This work allows for identifying the opportunities, challenges and shortcomings of this powerful and convenient, yet still not fully discovered analytical approach.