Recent development and applications of poly (ionic liquid)s in microextraction techniques

Microextraction techniques have been developed rapidly in recent years due to their numerous advantages including simplicity, miniaturization, cost-effectiveness, easy automation, low consumption of sample and eco-friendliness. Poly (ionic liquid)s (PILs) belong to a subclass of polyelectrolytes which are characterized by a series of unique physicochemical features including high thermal, chemical and mechanical stability, excellent plasticity and spatial controllability. PILs have attracted considerable attention in sample pretreatment. This review mainly concentrates on the recent development and applications of PIL-based sorbents in microextraction techniques. The properties of PIL-based sorbents, their general preparation approaches, application in enrichment, the current problems and future prospects are overviewed. The formats of microextraction techniques discussed in this review include solid phase microextraction, monolithic fibers solid phase microextraction, in-tube SPME, magnetic solid phase extraction, stir bar sorptive extraction, stir cake sorptive extraction and tip-based microextraction. (C) 2019 Elsevier B.V. All rights reserved.