| Natural disasters such as tsunamis often leave local water sources
tainted with harmful bacteria, and existing tests for contamination take
as long as three days to produce a result.
Now a USD 30,00 test that takes just half an hour has been developed at
Australia's Environmental Biotechnology Cooperative Research Centre near
Sydney. Antibodies attached to tiny magnets are added to the water so
when bacteria in the sample bind to the antibodies, they can be
concentrated with a magnet.
The sample is then injected into a 'bubble pack' containing chemicals
that break open the bacteria, allowing their RNA to escape. An enzyme
specially modified to work at close to room temperature then amplifies
the RNA so that it can be detected by an electrochemical sensor even if
very few bacteria are present. |