http://physicsworld.com/cws/article/news/2015/may/22/nanomachine-pumps-molecules-uphill
A new molecular pump capable of pumping other small molecules up an energy gradient has been developed by researchers at Northwestern University in the US. The new pump is very much like the protein pumps in living cells, and might be used to design artificial molecular machines similar to those found in nature. Such machines could be important for a range of applications, including synthetic muscles, tiny robots and advanced mechanical motors.
Molecular machines are ubiquitous in nature and have evolved over billions of years to exploit energy from sunlight or complex chemical reactions in the body. They are made up of complicated assemblies of proteins that are responsible for a host of processes in living organisms, such as ion transport, ATP synthesis and cell division. In fact, our muscles are controlled by the co-ordinated movement of thousands of these machines.
"Our new molecular pump is, in a sense, reminiscent of the pump proteins in our cells, which are vital components of life involved in transferring energy from food to a form that is compatible with our cells," explains Paul McGonigal, who is part of Fraser Stoddart's team at Northwestern. "We have designed a relatively simple small molecule that can also drive a system away from equilibrium with chemical energy from redox (oxidation-reduction) reactions."