Butterfly wings also exhibit anisotropic self-cleaning, superhydrophobic properties. The butterfly wings exhibit anisotropy on a one dimensional level, compared to the other biological materials, which exhibited the anisotropy on a two dimensional level. Butterfly wings are composed of overlapping layers of scales, that have the best self-cleaning properties in the radial directions. This anisotropic interface my prove important for fluid controllable interfaces. Alumina layers patterned from the original butterfly wing have been used to mimic the structure and properties of the butterfly wings. Additionally, butterfly wing mimetic structures have used to fabricate anatase titania photoanodes. Butterfly wing structures have also been made using layer-by-layer sol-gel-based deposition and soft lithography molding.