Charlottesville, May 16, 2005
By: Charlie Feigenoff
Public
health. Workplace safety. Homeland security. The Holy Grail
in each of these areas is a low-cost, accurate, easy-to-read
method for detecting harmful contaminants. Thanks to a collaboration
between two University of Virginia researchers, the ideal
sensor is well on its way to becoming a reality.
Engineer Matthew Begley and biochemist James Landers have
developed a dramatic new approach to building sensors capable
of identifying specific molecules. Begley brings to the
project his expertise in analyzing the behavior of materials
and structures at the nanoscale-at scales of a billionth
of a meter. And Lander directs a laboratory with an international
reputation for creating fluidic microchips used for rapid
bio-chemical analysis.
Begley and Landers have developed polymeric structures that
bend in the presence of a target molecule. These polymers
are much more flexible than the silicon that is used as
the basis for most current micro-devices. Although existing
silicon-based devices have been engineered to bend, they
deform only slightly, requiring specialized equipment to
measure their deflection. "Our goal is develop inexpensive
sensors that can be read in minutes without the use of expensive
hardware, such as lasers," says Begley.
Many polymers are biocompatible, making them particularly
useful for devices that conduct bio-chemical analysis -
for example, identifying airborne pathogens, whether in
a hospital, post office, or military base. With his expertise
in materials science and mechanics, Begley can determine
how the geometry and the properties of a polymer relate
to its deformation. This understanding also comes into play
in developing a microfabrication process to produce these
sensors on a large scale. "Currently, there's no systematic
or comprehensive technique to do this," Begley says,
"We're inventing a sensor and its microfabrication
pathway at the same time."
Begley is an associate professor in structural and solid
mechanics in the University of Virginia School of Engineering
and Applied Science Department of Civil Engineering. He
is a graduate of Pennsylvania State University and the University
of California, Santa Barbara. His research interests include
nano-to-microscale material science theory and experiments,
nano-indentation and impression, fracture and cyclic deformation,
applied mathematics and numerical solutions and dynamic
interface mechanics.
