Insights into Chemistry of Biological Materials: Newly Discovered Silica-Aragonite-Chitin Biocomposites in Demosponges

TLDR

Biological materials research offers evolutionary insights and biomimetic inspiration, with biocomposite structures providing novel chemistries and informing biomineralization mechanisms. The study aims to describe a novel silica–aragonite–chitin biocomposite from Verongida sponges. The biocomposite was examined with a diverse suite of analytical techniques. Analysis revealed a chitinous template for siliceous overgrowth that incorporates aragonite-based crystal aggregates.

Abstract

Biological materials are a rewarding area of modern materials science, yielding both evolutionary insights and inspiration for biomimetic research. In particular, biocomposite structures are valuable sources of novel structures with unusual chemical properties, and they are very informative for the mechanisms of biomineralization. Here we describe a unique biocomposite of amorphous silica, crystalline aragonite, and chitin from species of the order Verongida, a group of marine sponges. The structures have been analyzed with a diverse suite of techniques, revealing a chitinous template for siliceous overgrowth containing aragonite-based crystal aggregates. Sponge chitin is an example of a specific template where two minerals in amorphous and crystalline forms are formed together with an organic molecule.