Heavy metal complexation on hybrid mesoporous silicas: an approach to analytical applications

Recent advances in the development of new materials are having a major impact on Analytical Chemistry. For example, the unique properties of ordered mesoporous silicas have been shown to enhance the analytical performance of many existing techniques or allow new, exciting ones to be developed. Likewise, the introduction of organo-functional groups makes mesoporous silicas highly versatile and enables them to perform specialized tasks, such as the adsorption of toxic heavy metals from aqueous solutions. In this tutorial review, we present readers with a brief introduction to the most relevant achievements in the preparation of hybrid mesoporous silicas functionalized with chelating ligands for the complexation of heavy metals. We also provide some recent examples from the last ten years regarding the analytical applications of such hybrid silicas. Two topics of great current interest in environmental water analysis for heavy metal detection, namely the use of hybrid mesoporous silicas as sorbents for solid-phase extraction and the use of these materials to develop new strategies for electrochemical detection of heavy metals by stripping voltammetry, are addressed.