Extremely cool, but not a patch on nature’s own molecular machinery
They are worm drive assemblies, designed by Eric Drexler, Josh Hall, Ninad Sathaye and Mark Sims. The design contains 11 components and is made from 25, 374 (virtual) atoms. The simulations, which took 340 hours to complete,were created using NanoEngineer-1 Alpha 7 software on a Dell laptop running Windows XP.
Here’s another. It’s a speed gear reducer, containing about 15,000 atoms:
It’s only a matter of time – perhaps decades – before nanotechnology, combined with microelectronics and optofluidics, is applied to the development of devices such as artificial retinae, neuron-semiconductor interfaces and neuromorphic chips; but the idea of a brain implant which uses biological molecules to store data, and can back-up human memories which might otherwise be lost to degenerative disease, will remain in the realm of science fiction for a long time yet. (Update: Harvard researchers have created artificial synapses using nanowires.)
Nanotechnology will eventually drive the miniaturization of brain-machine interfaces and other similar devices, which are modelled on biological processes and architecture, and will perform many of the functions of the human nervous system, without even approaching its staggering level of complexity.
The two animations at the top, which contain about 25,000 atoms, are the most complex simulations ever created using this software, and they haven’t even been built yet. By comparison, an ion channel– which is among one of nature’s most sophisticated nanomachines – can have a molecular mass approaching 1,000 kiloDaltons, and contains millions of atoms.
The voltage-gated potassium ion channel (above) is just one of dozens of proteins that are involved in generating the action potential and mediating intercellular communication in the nervous system, by precisely controlling the movements of ions, millisecond-by-millisecond, across the nerve cell membrane. It is embedded in the membrane, and contains a negatively-charged pore at its centre, which opens and closes in response to changes in the difference in voltage between the inner and outer surfaces of the membrane. When open, the pore allows the passage of positively potassium ions – but no other type of ion – out of the nerve cell.
Would a nanofactory ever be capable of mass-producing something like a voltage-gated ion channel?