The smallest water bottle ever made

This week researchers announced they'd used a microscopic "carbon cage" to hold a single water molecule. How did they do it?

Nature blog The Great Beyond sums up:

Many researchers have used the carbon spheres called fullerenes to surround molecules. An international team has now taken the crucial next step and designed a ‘stopper' that can plug an open fullerene but can also be removed to allow a molecule of water in and out. In the future such 'molecular vials' could be used to transport radioactive atoms or small molecules for medical purposes such as imaging, they suggest.

via The Great Beyond