Luminescent silica based nanostructures from <i>in vivo</i> Iridium-doped diatoms microalgae.

摘要： A novel biotechnological approach to the preparation of Ir-doped luminescent silica based nanostructures is proposed availing of diatoms microalgae which generate highly nanostructured biosilica shells (frustules) by in vivo biomineralization of orthosilicic acid. After the in vivo incorporation of a phosphorescent organometallic complex (Ir-1) in Thalassiosira weissflogii diatom frustules (DFs), bulk functionalized phosphorescent silica based nanostructures are obtained by isolation and proper ultrafine processing of Ir-1 doped DFs. High-resolution characterization reveals the presence of phosphorescent hybrid organic/inorganic clusters (HCs) composed of biogenic silica NPs intimately trapped within the diatom organic residual matter. The bio-factory strategy investigated herein can be a sustainable, cost-effective and scalable route to transition metal doped silica nanomaterials, and can pave the way to a great variety of heavy-metal and rare-earth metal doped silica nanostructures, whose applications range from photonics to imaging, sensing and biomedicine.