Due to the easier preparation, better permeability and higher column efficiency over traditional packed columns, monolithic columns have gained increasing interest as separation media in all chromatographic methods. In recent years, with the rapid development of nanoscale chromatographic separation systems, the use of capillary monolithic columns have emerged as a promising choice. According to the chemical composition of monoliths, monolithic columns can be mainly classified into organic polymer-based, silica-based and organic-silica hybrid monolithic columns. Each of monoliths is tended to be prepared with versatile functionality. However, silica-based monoliths aways suffer from limited silylating reagents and complex processes of modifications, and conventional approaches of preparing polymer-based monoliths and organic-silica hybrid monoliths also prevent their development due to the special requirements of functional monomers (possess vinyl or acrylate groups). Recently, thiol-ene "click" reaction has already received extensive attention in the field of monolith preparation owing to its exceptional versatility and propensity for the quantitative conversions under mild conditions, extending the choice of categories of functional monomers to some extent. Herein, the fabrication approaches are comprehensively summarized with two routes: (1) surface modification of monoliths via thiol-ene "click" reaction, (2) "one-pot" synthesis of monolithic columns via thiol-ene "click" reaction.

Contents
1 Introduction
2 Application of thiol-ene "click" reaction in the field of monolith preparation
2.1 Surface modification of monoliths via thiol-ene "click" reaction
2.2 "One-pot" synthesis of monolithic columns via thiol-ene "click" reaction
3 Conclusion and outlook