Public Release: 

New Sensor Will Detech Chemical And Biological Pathogens At Incredibly Small Doses

Virginia Tech

(Blacksburg, Va., Feb. 20, 1998) -- During the 1991 Persian Gulf War when the first real threat of biological warfare was heralded, dozens of pathogens went undetected, mostly because of the limited technology available to the military.

To detect many of these weaponizable biological agents (WBA), a sensor must be able to identify a pathogen at a measurement of parts per trillion. Technology available during the Gulf War only allowed measurements of parts per billion.

A novel sensor, developed by two Virginia Tech engineering faculty members, is now capable of literally identifying "a needle in a haystack," says William Velander, one of the inventors. His device has showed results that are 20 times more powerful than previous sensing devices.

Velander, a biochemical engineer who heads Virginia Tech's Pharmaceutical Engineering Institute, teamed with Kent Murphy, a fiber optics expert and a member of the electrical engineering department, to develop the prototype biosensor.

To develop the new biosensor, Velandar expanded upon some of his previous work. He adapted a technology he invented that is employed to purify pharmaceuticals present in blood plasma at trace levels. By combining his scientific process with an optical fiber sensing device, Velander and Murphy have found that they can "capture biological warfare agents" that were previously undetectable.

For example, the prototype biosensor detects endotoxin at a level that is 20 times lower than previously achieved by other devices. "Endotoxin is composed of compounds called lipopolysaccharides found in bacteria such as E.coli. The presence of endotoxin from a blood borne infection (sepsis) of a gram negative bacteria can cause clotting, organ failure and subsequent death," Velander explains.

Velander estimates there are several hundred WBAs that currently exist that can induce battlefield and civilian casualties that can now be detected. "The new biosensor approaches the sensitivity of a dog sniffing airborne chemicals," Velander adds.

Another advantage of the new sensor is its speed. Current technology for detecting certain pathogens, in addition to being less sensitive, is also time consuming. It typically requires an hour or more of laboratory based effort. This new biosensor produces its finding in close to "real time," Velander says, or in just a few seconds.

Velander's partner, Murphy, is also the president of Virginia's fastest growing technology company, F&S Inc. The Blacksburg-based company funded the work, and it now plans to market the new technology through a second company called Luna.

At this time, the research prototype is not field deployable, Velander emphasizes. Its size is its current drawback; although, with investment capital, Velander asserts that the biosensor can be made into a belt-pack size, battery-generated portable device, capable of being taken onto a battlefield.

Murphy and Velander envision other applications, including pharmaceutical manufacturing, environmental monitoring, medical diagnostics, drug discovery, and process control.

"One of the biggest applications will be in drug discovery work," Murphy says. It can take six to nine months to screen libraries of new chemicals, but with the new sensor, configured in an array of 100 fibers, a determination could be made within a few weeks. A typical library can contain between 10,000 and 10 million compounds from which to choose a new drug. "This application is extremely exciting," Murphy adds.

He indicated that he is speaking with government agencies and industrial laboratories about supporting this work.


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