WASHINGTON, Sept. 6 (UPI) -- Traditional lab tests for the Escherichia coli bacteria can take 24 hours or longer -- delaying the time to prevent infections in contaminated food, water or other environment -- but researchers in Canada have created a device to speed up that process considerably.
Scientists at the University of Quebec and the Indian Institute of Technology Kanpur created a device that can test for E. coli in 15 to 20 minutes, according to a proof-of-concept study published in the journal Optics Letters.
The device, they say, could speed up the time to test foods and bodies of water for the bacteria and prevent outbreaks of infection which pose significant health risk, especially to children and the elderly.
"Pathogenic bacterial infection is one of the biggest causes of death, and a fast response time is much needed for timely detection and subsequent cure of bacterial infection," Saurabh Mani Tripathi, a physicist at the Indian Institute of Technology Kanpur in India, said in a press release. "I'm excited by the very low time [our sensor needs] to accurately detect the presence of E. coli bacteria in water collected from environments at different temperatures."
The sensor at the center of the device uses bacteriophages, viruses that latch onto and kill bacteria, to detect E. coli. The scientists bonded the bacteriophages to the surface of optical fibers, and when bacteria are grabbed by the viruses, the wavelength of light against the optical fibers changes, indicating the presence of E. coli.
Scientists also had to make the sensor work in variable temperatures, adding another component to balance out shifts in the optical fibers caused by changes to the temperature. This, the scientists say, could allow devices based on the sensor to be used indoors and outdoors.
The sensor can also detect other strains of bacteria by changing the bacteriophage, expanding any potential device's usefulness.
The scientists are working with the Canadian company Security and Protection International, Inc., to create a commercial device they hope will cost a few thousand dollars.
"Using currently available technologies, which are mostly based on amplification of the sample, it takes several hours to days to detect the presence of bacteria," Tripathi said. "A fast and accurate detection alternative is, therefore, preferable over the existing technology."
