Biosensor Speeds Up Detection of Contaminated Food.
Contaminated food could be a thing of the past with a bacterial sensing device from the Georgia Tech Research Institute, Atlanta (404-894-3503). This interferometric technology can detect pathogens in less than two hours, rather than the 24 hours other tests currently take. The equipment also costs thousands of dollars less. Someday it might be feasible to integrate the system into commercial processing procedures for meat, produce, dairy, and seafood.
The biosensor operates with three primary components--immunoassay techniques, surface chemistry tests, and integrated optics. A series of antibodies on the immunoassay selectively recognize target bacteria. A "capture" antibody is bound to the biosensor and captures the target bacteria. A set of "reporter" antibodies, which binds with the same target pathogen, breaks down the urea and produces ammonia. The chemical sensor detects the ammonia and signals the presence and concentration of the pathogens.
The biosensor can simultaneously detect 12 pathogens including Salmonella, E. coli 0157:H7, generic E. coli, Listeria monocytogenes, Campylobacter jejuni, and Yersenia enterocolitica. While current lab tests are only sensitive enough to detect 5,000 pathogen cells/mL, the biosensor can detect as few as 500 cells/mL.
But the biosensor still needs to complete field tests before it becomes commercially available. Phase I testing to duplicate lab results will begin in November at Gold Kist, Carrollton, Ga., and will last three to six months. Researchers also hope to broaden the biosensor's detection capabilities to include pesticides, insecticides, and growth hormones.
|Printer friendly Cite/link Email Feedback|
|Comment:||Biosensor Speeds Up Detection of Contaminated Food.|
|Publication:||R & D|
|Article Type:||Brief Article|
|Date:||Nov 1, 1999|
|Previous Article:||Home Page.|
|Next Article:||Alternative Source Challenges Blue Lasers.|