October 22, 2001. Copyright 2001. Graphic News. All rights reserved.

New system can test for anthrax in 15 minutes 

LONDON, October 22, Graphic News: Until now, reliable biological analysis of bio-terrorist threats, such as anthrax, has meant sending a sample to a centralized laboratory while local emergency authorities wait up to 48 hours for test results.

The two established methods for confirming anthrax involve either culturing the suspect organism and then using a barrage of chemical tests to identify it, or using a sophisticated technique known as polymerase chain reaction (PCR) to amplify and identify its DNA in order to make a Ògenetic fingerprint.Ó

Both procedures take days and PCR can only be performed in a specialized laboratory, so, even if the result is negative, the hoax or act of terrorism may already have caused chaos. Now a new 15-minute field-testing kit is available to Òfirst respondersÓ who handle suspect bio-terrorist attacks. 

As potential victims are disrobed and showered, a responder wearing a level-A protective suit takes a sample of the suspect material, solid or liquid, and places it in a small vial along with a buffer solution, which prepares the sample for testing. He then opens a foil pouch containing an ÒAnthrax BTA Test StripÓ and places five or six droplets onto the sample port of the test strip using an eyedropper. 

Antibodies specific to anthrax are present on the strip and attach themselves to any Bacillus anthracis in the sample. When this happens, the antibodies detach themselves from the strip and migrate along it -- a technique known as lateral-flow immunochromatography -- to reveal two red stripes printed underneath. For forensic purposes, each strip also carries a microchip that stores details of the field test. Minutes later the strip confirms whether the threatening substance is anthrax. 

For a more accurate confirmation the strip is placed in a Test Strip Reader. The reader offers greater accuracy, as its optical technology can recognize positive results that might be missed by the human eye, due to faint positives or poor ambient lighting. The results are displayed on a LCD display as well as on a printout. Security technology also ensures that the Òchain of custodyÓ is documented for each individual BTA strip test; documentation crucial in a criminal investigation.

The test strip -- which costs $20, and looks like a pregnancy-detection kit -- has been developed by Alexeter Technologies, of Wheeling, Illinois and and Tetracore, of Gaithersburg, Maryland. The Guardian Bio-Threat Alert System is the only rapid field test now available to emergency authorities.

Tom Fryzel, the marketing manager of Alexeter Technologies, says that in the past fortnight the company has shipped what would normally be three monthsÕ inventory to emergency services, corporate-security outfits, groups connected with the armed forces and a few places Òthat you can probably imagine but we cannot talk about.Ó

The founders of Tetracore were part of a team of scientists from the Naval Medical Research Institute, in Bethesda, Maryland. They have developed test strips to detect Ricin toxin, Botulinum toxin and Staphococcal Enterotoxin BÊ(SEB), and are now working on new methods for detecting a range of infectious agents including plague and smallpox, using field versions of gene-amplification technology. A particularly promising line for the company is a genetic field test for foot-and-mouth disease, which it hopes will be brought out in Brazil this week. The test works in an hour, and can detect the virus even before symptoms have appeared.
/ENDS
Source: Alexeter Technologies