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A straightforward approach for anchoring tailored carboxylic groups in mesoporous SiO2 colloidal materials is presented. The thiol-ene photochemical reaction between vinyltrimethoxysilane precursors and various thiocarboxylic acids which has, click chemistry features (i.e. high conversion yields, insensitivity to oxygen, mild reaction conditions), results in carboxylated silane precursors that can be readily used as surface modifiers. The carboxylic groups of acetic, undecanoic and succinic acid were immobilized on the silica mesopore walls of SBA-15 powders employing the synthesized silane precursors. Post-grafting has been confirmed through infrared spectrometry (FTIR), energy dispersive X-ray spectroscopy (EDS), elemental analysis (EA) and zeta potential measurements. Detailed field-emission gun scanning electron microscopy (FESEM) images and small angle X-ray scattering (SAXS) data revealed parallel mesopores and ordered mesostructures. It is shown that the immobilized COOH groups are chemically accessible for acid-base reactions as well as copper adsorption. Immobilization of easily synthesized tailored carboxylic modified alkoxide precursors within mesoporous systems provides a unique chemical nanoenvironment within these ordered frameworks., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Here we report the derivatization of mesoporous TiO2 thin films for the preparation of H2O2 amperometric sensors. The coordination of the bifunctional ligand 1,10 phenantroline, 5,6 dione on the surface Ti(IV) ions provides open coordination sites for Fe(II) cations which are the starting point for the growth of a layer of Prussian blue polymer. The porous structure of the mesoporous TiO2 allows the growth, ion by ion of the coordination polymer. Up to four layer of Prussian blue can be deposit without losing the porous structure of the film, which results in an enhanced response of these materials as H2O2 sensors. These porous confined PB modified electrodes are robust sensors that exhibit good reproducibility, environmental stability and high sensitivity towards H2O2 detection., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Rational design of fully synthetic platforms displaying active control over ionic transport in close resemblance to biological systems represents an ongoing challenge in molecular materials science. Here, we demonstrate that the synergism arising from the chemistries involved in mesoporous films and polymer brushes is a key enabler to next-generation "smart" nanofilters capable of mimicking the gating functions of specific biological channels. Hybrid functional assemblies constituted of mesoporous silica films modified with polyzwitterionic brushes are able to discriminate and gate the transport of cations while the passage of anionic species is precluded. The synthetic membranes behave as proton-gated cation-selective platforms mimicking the functioning of acid-sensing ion channels encountered in the neurons of the central nervous system. We believe that this experimental evidence will stimulate further multidisciplinary work across the boundaries of materials chemistry to attain new functional nanostructured interfaces with transport properties so far believed to be exclusive features of biological channels.