Template mineralization of self-assembled anisotropic lipid microstructures

Abstract

THE high-fidelity replication and functional specificity of biomaterials and biopolymers is inspiring a renewal in the development of biomimetic strategies for materials synthesis^1,2. Approaches involving the templating or nucleation of inorganic materials by compressed monolayers of amphiphiles^3–5, the use of supramolecular lipid or protein cages in the preparation of nanoscale inorganic structures^6–8 and the mineralization of bacterial fibres⁹ indicate the potential of controlled crystallization at inorganic–organic interfaces. Here we report the controlled formation of tubular inorganic–organic composites by using self-assembled lipid tubules as templates for the crystallization of inorganic oxides. We use microstructures formed by a sugar-based lipid galactocerebroside, doped with small amounts of an anionic sulphated derivative, to induce nucleation of magnetic and non-magnetic iron oxides. By varying the reaction conditions, we can create either tube-like or lamellar disk-like composites. Our results suggest that the variety of microstructures formed by chemically modified sugar-based lipids may provide a route to the production of mineral-containing fibres and other ceramic–organic composites.