Nanoscale elevators made of two interlinking organic molecules have been built and operated by US and Italian scientists.

They are the most complex molecular machines built yet, consisting of a platform flanked by three rings that thread through three vertical rods. The force of an acid-base reaction is used to power the “elevator.”

The most likely application will be in bringing two reactants together, allowing tight control over the timing of a reaction.

Further in the future, the elevators could act as pistons for remote-controlled drug delivery inside the body.