Biomimetic Mineralization of Uranium by Metabolically-Inactive Shrimp Shell

Abstract

Biomineralization in crustaceans is a remarkably efficient process of ion transport and phase transformation in a spatial template. Here we show the use of this preorganized pathway with waste shrimp shell as both a phosphate source and template for the mineralization of UO22+ to uramphite. By using the physical structural and chemical reservoir of the biogenic platform, the only requirement was to develop a solution for ion supply. Hydroxylammonium acetate, an amphiprotic salt parallel to the amine and carboxylic acid motif pervasive in biomolecules, was prepared and used for the delivery of dissolved uranyl ions into the spatial constraints of the exoskeleton. Although biomediated phase transformations of exogenous metals is typically limited to living organisms, our results show that metabolically inactive shrimp shells are adaptive and responsive toward a nonessential ion. This suggests the nonliving exoskeleton may provide rapid bottom-up assembly routes to technologically important new inorganic crystalline materials.