from the chemists-in-hot-pursuit dept.
Foresight chairman Eric Drexler calls our attention to a review in the 9 November issue of Nature "In Control of Molecular Motion" by chemist Ben Feringa of Univ. of Groningen, The Netherlands: "Nature [he means Mother Nature, not the journal –CP] leads the way when it comes to motors on a molecular scale. But chemists are in hot pursuit, designing controllable structures that can mimic muscles or rotary motors."
Read more for excerpts, see the paper journal in your library, or buy the article online for US$10. Excerpts:
"Most artificial systems that produce linear or rotary motion are more like molecular switches than motors. It is not enough to build a system that moves or rotates freely. To reproduce the actions of a motor it is essential to incorporate control into the system, so the motion can be started or stopped at will. There are many ways to do this…
"But this is the first demonstration of stretching and contracting motions induced by a chemical reaction in an artificial molecular assembly. The stage is set for the design of other 'molecular muscles' triggered by electrochemical or photochemical processes. For these artificial molecular muscles to perform useful mechanical work, they will ultimately have to be connected to macroscopic systems. The organization and concerted action of a large number of these molecular motors is one of the key issues to address…
"The chemical control of rotation is a powerful tool to be used in more advanced molecular motors. But there are many hurdles to overcome before the structures designed by these and other groups lead to molecular machinery becoming a reality. To make their construction easier, self-assembly processes are needed. It is also not clear whether the motors described here will retain their properties when they are used as part of a more complex system. Nonetheless, we are adding important components to our toolkit for making nanomachines."
