|
07 October 2009
Directing the movement of single molecules
A team from the Departments of Physics and Astronomy and Chemistry led by Mark Geoghegan have shown how to move single molecules in a given direction without the use of any external stimuli such as electric fields.
The method involves simply changing the nature of the surface onto which the molecules adsorb. Molecules of the polymer polyethylene glycol were shown to diffuse from a water-repellent surface to a water-attractive (hydrophilic) surface. It is known that by creating surface gradients that gradually go from one property to another, it is possible to make materials move but this is the first time it has been shown to work with single molecules. The size of the path is 1000 times bigger than the size of the polymer, so the polymer is very sensitive to the gradient.
The control of single molecules is a key goal of nanotechnology. If one wishes to make complex structures with individual molecules, one must be able to put those molecules where they are needed. Dr Geoghegan and co-workers have shown one way to achieving this goal.
The work is published in the journal ACS Nano.
|
