The RSC web site features an article on molecular machines written by Josh Howgego that gives a very good brief introduction to the topic: Rise of the molecular machines. A downloadable PDF of the article as it originally appeared in Education in Chemistry provides better images of the figures than does the HTML version. The article explains how chemists have worked to mimic the function of biological molecular machine like muscles, by using intermolecular forces to control movements of mechanically interlocked molecules. The first example given is from the work of Fraser Stoddart, winner of the 2007 Feynman Prizes in Nanotechnology for Experimental work and Co-Chair of the January 2013 Foresight Technical Conference: Illuminating Atomic Precision, which will feature a session on “Molecular Machines and Non-Equilibrium Processes,” which Prof. Stoddart will chair. The article goes on to explain that harnessing simple molecular shuttles of the type pioneered by Stoddart to do real work like muscles has proved difficult, and cites as a prototype solution a molecular machine that works in a different way: a walker that sequentially makes and breaks different types of covalent bonds, developed by David Leigh, winner of the 2007 Feynman Prizes in Nanotechnology in the Theory category. The article finishes with a description of a nanocar developed by Ben Feringa that uses electricity to move across a metal surface by rotating paddle-like wheels.
—James Lewis, PhD