Nano-machines achieve huge mechanical breakthrough

[Guest guest]

Nano-machines achieve huge mechanical breakthrough

(NOTE: Read about how artificial muscles can perform physical tasks with this

breakthrough! ~ Gretchen)

http://www.medicalnewstoday.com/medicalnews.php?newsid=30340

08 Sep 2005

A major advance in nanotechnology with far-reaching potential

benefits in medicine and other fields is to be announced at this

year's BA Festival of Science in Dublin.

Scientists have built molecules that can, for the first time ever,

move larger-than-atom-sized objects. Constructing molecular machines

capable of performing relatively large-scale mechanical tasks has

never been achieved before.

Now, in an unprecedented breakthrough, chemists at Edinburgh

University have used light to stimulate man-made molecules to propel

small droplets of liquid across flat surfaces and even up 12° slopes

against the force of gravity. This is equivalent to tiny movements in

a conventional machine raising objects to over twice the height of

the world's tallest building.

This significant step could eventually lead to the development of

artificial muscles that use molecular 'nano'-machines of this kind to

help perform physical tasks. Nano-machines could also be used

in 'smart' materials that change their properties (e.g. volume,

viscosity, conductivity) in response to a stimulus. They could even

control the movement of drugs around the body to the exact point

where they are needed.

The research has been funded by the Engineering and Physical Sciences

Research Council (EPSRC), and has also involved scientists in Italy

and the Netherlands. Leigh, Forbes Professor of Organic

Chemistry and EPSRC Senior Research Fellow, leads the Edinburgh

University team.

Leigh and his colleagues have achieved their breakthrough by

harnessing a natural biological mechanism called 'Brownian motion'

(the random movement of molecules caused by collisions with molecules

around them). This has involved controlling (or 'biasing') Brownian

motion so that molecule movements are no longer completely random.

The team has developed a way of covering a gold surface with

specially engineered molecules. When stimulated by ultra-violet

light, the components of these molecules change position (this is

because a chemical reaction takes place in one part of the molecule

that causes it to repel another part). These changes in position

dramatically alter the surface tension of a droplet of liquid placed

on the gold surface and in this way produce enough energy to move the

droplet a distance of up to a millimetre. It may be the tiniest of

movements but in the emerging discipline of nanotechnology this

represents a giant technological leap forward.

Leigh says: " Nature uses molecules as motors and machines in

all kinds of biological and chemical processes. Although man's

understanding of how to build and control molecular machines is still

at an early stage, nanoscale science and engineering could have a

life-enhancing impact on human society comparable in extent to that

of electricity, the steam engine, the transistor and the Internet. "

Leigh will be discussing his work and showing videos of droplet

movement during his talk at the Festival on 7th September. A detailed

report has also been published in the latest edition of Nature

Materials ('Nanoshuttles move droplets uphill'; Vol. 4, pp.704-710,

2005).

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Nanotechnology involves manipulating materials on a very small scale

to build microscopic machines. The prefix 'nano' in 'nanotechnology'

means one thousand-millionth (10-9). A nanometre, for example, is one

thousand-millionth of a metre.

This year's BA (British Association for the Advancement of Science)

Festival of Science takes place in Dublin from 3rd -10th September.

The event is one of the UK's biggest science festivals and attracts

around 400 of the best scientists and science communicators from home

and abroad who reveal the latest developments in research to a

general audience. For more information visit http://www.the-ba.net.

Professor Leigh will be talking about " Tooling Up for the

Nanoworld: The Magic of Molecular Machines " from 14.00 to 16.00 on

7th September at Joly LT, Hamilton Building. Professor Leigh will

also be taking part in a press conference at 09.00 on 7th September

where he will be discussing his work. Professor Amilra de Silva of

Queen's University Belfast, with whom Professor Leigh has worked

extensively in the past, will be talking about " Luminescent Molecules

as Information Processors " on the same day and will also be taking

part in the same press conference.

The Engineering and Physical Sciences Research Council (EPSRC) is the

UK's main agency for funding research in engineering and the physical

sciences. The EPSRC invests more than £500 million a year in research

and postgraduate training, to help the nation handle the next

generation of technological change. The areas covered range from

information technology to structural engineering, and mathematics to

materials science. This research forms the basis for future economic

development in the UK and improvements for everyone's health,

lifestyle and culture. EPSRC also actively promotes public awareness

of science and engineering. EPSRC works alongside other Research

Councils with responsibility for other areas of research. The

Research Councils work collectively on issues of common concern via

Research Councils UK. Website address for more information on EPSRC:

http://www.epsrc.ac.uk

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