`Natural` bones and teeth
GERMAN chemists have managed to mimic nature by creating synthetic pearls. The team's ultimate aim is to build artificial teeth and bones out of the same minerals used by nature. For the first time the scientists have claimed to build specific three-dimensional inorganic materials from simple molecules. Pearls are made when oysters lay down layers of the mineral calcite (calcium carbonate, which occurs in variety of forms in limestone marble and other rocks) onto a 'seed' molecule, usually a grain of sand.
Wolfgang Tremel and his team from the University of Mainz, Germany, managed to recreate this process. "We used the fact that calcite is readily deposited from aqueous solution onto a pre-treated gold surface", said Tremel. Calcite crystals usually grow into cubes, but the researchers found a way to get round this problem. "We prepared small gold spheres with specially treated surfaces; the calcite then formed a layer on the gold and continued to grow outwards in spherical form." he added.