Linking of Chemical Reactions and Silica Nanoparticle Contact Using Synthetic Helical Molecules.

Comprehensive Summary: Biological cells exhibit diverse phenomena induced through linking of chemical reactions of molecules and solid surface contact. It is then a significant topic in the field of chemistry to study phenomena induced through this linking using synthetic systems, which can promote our understanding of biological phenomena and can be applied to the development of novel functions. Silica nanoparticles (SNPs), which are synthetic inorganic materials, are attractive for such purposes, because of their following characteristics: they can adsorb large amounts of molecules on their surfaces, they can aggregate through contact between SNPs as well as contact between molecules and SNPs, and the molecules can be easily removed from solutions by precipitation. The contact of SNP surfaces with molecules then affects chemical reactions of molecules and also behaviors of SNPs. This article describes systems derived from synthetic helical molecules and SNPs, which exhibit notable phenomena including selective adsorption and molecular recognition, equilibrium shift, step kinetics with induction period, precipitation with flow and sweeping, and disaggregation and desorption by sonication, in which the high affinity of helical molecules with SNP surfaces plays important roles. Mechanistic models that explain the phenomena are provided. Possible applications are also discussed, including the separation of molecules, capture of intermediates, the storage and release of molecules, equilibrium shift, clocking, and the translation of mechanical stimulations into chemical reactions. Key Scientists: [ABSTRACT FROM AUTHOR]