Macromolecular Condensates as Tunable Scaffolds for Bio-Inspired Silica Hybrids

Silica-based materials are of immense functionality as their production is versatile and can accommodate a wide range of properties. Nevertheless, no synthetic system can reproduce the ability of organisms to precipitate dense silica under ambient conditions and from dilute soluble precursors, leaving a substantial gap in our understanding of silica chemistry. It is widely accepted that a key feature of biosilicification is the activity of amine-rich macromolecules, but their biomimetic use in silica synthesis currently fails to reproduce biological processes. Here, we take inspiration from some properties of biological processes and demonstrate that phase separated polyamine condensates drive the formation of hybrid silica materials. We further show that the pH of the reaction is a regulator that allows to control the architecture and composition of the silica material. These results point to the fundamental role of condensates in driving silicification from dilute aqueous environments that characterize physiological conditions. Applying these sets of rules to synthetic systems may open the road for the production of a new class of dense and biocompatible silica hybrids.