Harvard | Two of the world’s biggest threats may someday be reduced by wires
thousands of times thinner than a hair but capable of detecting a single
virus. The specter of worldwide viral epidemics is always with us, so
detecting them quickly offers the possibility of saving thousands of
lives. The pathogens also can be stealthy biological weapons, making
their positive detection a vital national defense requirement.
“We want to find a single virus before it finds you,” says Charles
Lieber, Hyman Professor of Chemistry at Harvard University. Tests
recently completed in his laboratory show that these unimaginably thin
nanowires can sense and distinguish between viruses that cause flu,
measles, and eye infections. Lieber believes future versions will be
able to spot HIV, Ebola, SARS, West Nile, hepatitis, bird flu, and other
dangerous viruses.
“Viruses are among the most important causes of human disease and are
of increasing concern as agents for bioterrorism,” Lieber says. “Our
work shows that nanoscale silicon wires can be configured as detectors
that turn on or off in the presence of a single virus particle. Such
detectors could be fashioned into arrays capable of sensing thousands of
different viruses, ushering in a new era for diagnoses, biosafety, and
quick response to viral outbreaks.”
“Nano” refers to a “nanometer,” one billionth of a meter, four hundred billionths of an inch, or about 10 atoms in size. One hundred
thousand wires, each 20 nanometers long, would fit on the head of a pin.
The Department of Defense, Office of Naval Research, and National
Cancer Institute all supported Lieber’s research, and at least two
commercial companies have shown interest in manufacturing nanosensors.
In his office, Lieber shows visitors a two-inch-square silicon and
metal chip containg an array of nanowires and two pinhead-size entry
ports through which blood, saliva, or other bodily fluids can enter. Air
samples put into a fluid solution would also be tested this way.
0 comments:
Post a Comment