MEDIA RELEASE
30 May 2006
Scientific breakthrough at Victoria
Researchers may one day be able to reliably track a single molecule as it moves through the human body thanks to a
discovery by Victoria University academics.
Associate Professor Pablo Etchegoin, Dr Eric Le Ru and Matthias Meyer, from the School of Chemical & Physical Sciences, have published a paper in the Journal of Physical Chemistry on the detection of single molecules
using Surface-Enhanced Raman Spectroscopy (SERS).
The paper has been touted as providing the most conclusive experimental proof available so far on the detection of
single molecules via SERS, says Associate Professor Etchegoin.
“Even though the possibility of detecting single molecules has been proposed several years ago and several researchers
have reported single-molecule sensitivity, all of the studies have relied on indirect evidence; a problem that this new
study overcomes.
“The extreme sensitivity of the technique could in principle be applied in many different ways. One example could be to
trace minute quantities of illegal substances, from drugs to explosives. Many forensic scientists would like to be able
to have a technique that can detect extremely tiny amounts of illegal substances, something beyond anything that can be
detected reliably and efficiently now.
“Another potential use is in biology. By adding dyes to DNA or antibodies, for example, medical researchers may even one
day be able to track single molecules as they move through the human body. If achieved, this could be of great benefit
in diagnosing and treating diseases.”
To detect such minute quantities of molecules, ultra-sensitive spectroscopy is used. Raman Spectroscopy is a technique
used to detect minute quantities of molecules, using a laser to scatter light. SERS – in which a rough metal surface is
used to enhance the scattering effect – is still under development, and detecting single molecules using this technique
is still extremely difficult, says Associate Professor Etchegoin.
ENDS