Water beads on cotton, 2006.
© Science Museum / Science & Society Picture Library
Water droplets on a nano-tech polo-neck jumper. Nano-sized treatments can give fabrics novel and useful properties. Synthetic materials draw moisture away from the wearer's skin, just like cotton. Spills don't soak in, they just roll away. Stubborn stains wash out easily and smells never get stuck in. But while the technology might be new, and the products cutting-edge, the scientists who created them looked to nature for inspiration. The leaves of the self-cleaning lotus lily, and the more familiar nasturtium, are covered with waxy crystals only 1 nanometre across. They form a coating that roughens the leaf's nanostructured surface and causes water droplets to form into beads. As the beads run away, they take dust and dirt with them, leaving the leaves clean and glossy green.