Single-Step Dispersion of Functionalities on a Silica Surface

Abstract

A new process for coating a mesoporous silica gel with a mixture of the grafting reagents para-aminophenyltrimethoxysilane and phenyltrimethoxysilane is thoroughly analyzed. The dilution of para-aminophenylsilane with phenylsilane at different ratios allows the density of the functional amino groups present on the silica surface to be controlled, while keeping constant the overall number of grafts. Furthermore, the choice of a rigid linker prevents undesirable interactions between the active function and the inorganic support that could alter the function reactivity. This simple and new method, which results in the improvement of the dispersion of a functionality in a one-pot synthesis, could be particularly interesting in the field of supported catalysis and molecular recognition. The dispersion of the functional groups of the synthesized hybrid solids is investigated using a pyrene derivative covalently linked to the free amino groups of the para-aminophenylsilanes by analyzing the excimer and monomer fluorescence properties of the probe.

Heterobinuclear Light Absorber Coupled to Molecular Wire for Charge Transport across Ultrathin Silica Membrane for Artificial Photosynthesis

“…TMSA reacts with the silica surface by silanation, while TBAM forms three spider-like C-O-Si bridges by nucleophilic substitution of Br by surface O at the methylene carbon. [18] In a subsequent step, amide linkage between the NH 2 group of anchored TMSA and the carboxyl moiety of the PV3 molecule, catalyzed by HATU, results in covalent wire attachment. For casting of the wire molecules into 2 nm of silica, a modified Stoeber method described previously was used.…”

Discrete Complexes Immobilized onto Click-SBA-15 Silica: Controllable Loadings and the Impact of Surface Coverage on Catalysis

“…24,54–57 Pyrene is an ideal probe for intermolecular interactions due to the difference in fluorescence observed for the monomeric and excimer species. At a low loading ( x = 0.2), fluorescence is observed primarily due to the monomeric pyrene species (400 nm, Figure 5a).…”

Determinação Do Fator De Efetividade Para Enzimas Imobilizadas Usando Métodos De Regressão Simbólica via Programação Genética

“…O revestimento de um suporte com uma mistura dos reagentes sinalizantes como o 4-aminopeniltrimetoxisilano (APTS) e feniltrimetoxissilano (FTMS) e em diferentes proporções demonstraram que a densidade dos grupos aminados presentes na superfície da sílica pode ser controlada (BANET et al, 2008). Assim, um método simples pode garantir e até mesmo manter a dispersão da funcionalidade dos grupos aminos da superfície (BANET et al, 2008). Outra maneira que pode ajudar na imobilização e estabilização da enzima é a funcionalização do suporte através da adição de grupos aminas para posterior imobilização (Figura 3) (FIROOZ et al, 2017).…”