Scientists build world's smallest 'water bottle'

Scientists have designed and built a container that holds just a single water molecule. The container consists of a fullerene cage and a phosphate moiety that acts as the “cap” to keep the water inside.

The researchers, Qianyan Zhang, et al., from institutes in Beijing and Germany, have published their study on the tiny fullerene cage in a recent issue of Angewandte Chemie. While previous research has shown that fullerene cages can be used to surround molecules, here the chemists also designed a way to close (and re-open) the cage to let a water molecule in and out.

One of the keys was making the cap the exact size to allow a single water molecule to pass through, and modifying the classic carbon-60 form of fullerene accordingly. Due to its chemical properties, the phosphate moiety used for the cap can be easily removed and re-attached to the edge of an orifice in the fullerene cage, and can sufficiently lock a single water molecule inside.

The tiny container could have applications in transporting small molecules or radioactive atoms for medical purposes and other uses.