Current materials for miniaturized sample preparation: Recent advances and future trends

Developing new materials for sample preparation plays a crucial role in advancing sorbent-based microextraction technology. New extraction phases that provide high analytes recoveries, with enhanced discrimination of the matrix interferences, are continuously developed, improved, and assessed through multiple microextraction strategies. The synergy between the variety of sorbent materials currently available and the vast diversity of modern sorbent-based microextraction techniques provides a versatile toolkit for cheap, fast, and environmentally friendly sample preparation. Modern sample preparation materials include i) inorganic, organic, and natural polymers, ii) hyper-porous materials, iii) enhanced selectivity sorbents, iv) magnetic nanoparticles, v) carbon allotropes, and vi) ionic liquids, among many others. Thanks to those modern materials, in-field sampling alternatives, low sample-consuming techniques, and green analytical approaches are becoming more affordable, easily adaptable, and implementable. This review summarizes the advances in new materials for sorbent-based microextractions of the last five years (2019–2023), providing an update on a review paper previously published by our research group. In addition, more detached sorbents, innovative extraction modes, and representative applications will be described and discussed.