Template mineralization of self-assembled anisotropic lipid microstructures

THE high-fidelity replication and functional specificity of biomaterials and biopolymers is inspiring a renewal in the development of biomimetic strategies for materials synthesis1,2. Approaches involving the templating or nucleation of inorganic materials by compressed monolayers of amphiphiles3–5, the use of supramolecular lipid or protein cages in the preparation of nanoscale inorganic structures6–8 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.