Molecules in Glass: Probes, Ordered Assemblies, and Functional Materials

Abstract

Research on the properties and applications of molecules doped into sol-gel-derived silica matrices has expanded rapidly. This Account begins with a brief review of the use of the dopant molecules as probes of the changes that occur as the system evolves from the initial sol to the final xerogel during the formation of monoliths, thin films, and mesostructured films. Methods of deliberately placing desired molecules in specific regions of the mesostructure are discussed, and an application, energy transfer, is presented. Finally, encapsulation of biological molecules is examined, and two important aspects, stabilization of the biomolecules and applications as biosensors, are described.

Three dimensional macroporous architectures and aerogels built of carbon nanotubes and/or graphene: synthesis and applications

“…Hydrogels, organogels, and aerogels based on silica or carbon and consisting of micro-, mesoand even macroporous networks forming a hierarchical structure that guaranties molecular transport throughout the entire 3D architecture to gain access to the internal reactive surface are illustrative examples of 3D macroscopic assemblies corroborating this issue. [19][20][21][22][23][24][25] Thus, the aim of this review with regard to CNTs will be to summarize those self-assembling processes described to date that have been capable of building ''true'' 3D hierarchical macrostructures and have explored those applications where silica and carbon monoliths have already proved efficient (e.g. membranes and columns for water treatment and chromatographic separations, electrodes for supercapacitors, fuel cells and batteries, and catalytic substrates, among others).…”

“…[14][15][16][17][18] While recognizing the tremendous relevance of silica, hybrid-silica and carbon monoliths, the focus of this review will not be on these particular materials because there are already excellent reviews and books that cover most of the recent advances in this area. [19][20][21][22][23][24][25] Less revised has been however the preparation and application of composite-based monolithic aerogels and, in particular, of those containing carbon nanotubes (CNTs) and/or graphene. CNTs and graphene are both allotropes of carbon.…”

Bioimmobilization Matrices with Ultrahigh Efficiency Based on Combined Polymerizations of Chemical Oxidation and Metal Organic Coordination for Biosensing

“…19 2-D protocols offer favorable mass-transfer efficiency but often suffer from limited load and activity, since 2-D surface area is limited and the unprotected biomolecules are highly susceptible to environment. 20,23 In contrast, the 3-D protocols can provide more and protected sites for biomolecules; 24,25 however, the mass-transfer efficiencies are suppressed. More deeply, general strategies are based on the direct involvement of biomolecules on the interface of matrix, leading to limited conjugation/anchoring sites between the surfaces of biomolecule and matrix, as well as unavailable loss of activity due to the conformation change under mechanical and/ or chemical effects.…”

Probing the Microenvironment in the Confined Pores of Mesoporous Silica Nanoparticles

“…In this case, the emission from the RuBPy molecule has a relatively lower energy. On the contrary, when the surrounding environment is rigid, the solvent molecules will not reorient, and the corresponding emission from this RuBPy molecule is at a higher energy. , …”

“…The use of molecular probes and spectroscopic methods to reveal the properties of the confined environment in sol–gel films and monoliths has been well-developed. − Despite the success of those studies, little is known about the microenvironments of mesopores in silica nanoparticles. Mesoporous silica nanoparticles (MSNs) have been widely used in the field of controlled delivery, and many studies have been devoted to modifying the pore walls to accommodate the loading and docking of guest molecules. − Yet, there is limited quantitative understanding of the influences of the pore confinement on the guest molecules in these systems.…”