A working pump the size of a single human red blood cell has been made from pure glass, reports a paper published online this week in Nature Nanotechnology. The pump, which can control a flow rate of one thousandth of one trillionth of a litre per second, can be used to create tiny laboratories capable of analysing and synthesizing chemical and biological substances.

The device, created by Alan Hunt and colleagues, relies on the reversible transformation of very thin portions of glass from insulating to conducting states. Such glass electrodes open up new possibilities for fluidic machines.