Nanotrain transport system created by Oxford University scientists in action: The time-lapse video shows the network, with tracks shown in red, handling a cargo of fluorescent green dye over a period of eight minutes. There's a flash of bright green when the dye-carrying nanoshuttles are first added, which soon find their way onto the tracks. The shuttles are given ATP fuel at 209 seconds in, powering their journey to the center of the network. Once they reach the center at 319s, clean-up shuttles with the 'release' signal are sent in. These remove the dye from the network, leaving the tracks empty but for a few stragglers.