2 mimics what the dogs do: an artificial
nose. And malaria may just be the tip of
the iceberg. “We know that other diseases
have smells. If we can use the animals
to help us pick out the right smells then
we could develop diagnostics for any of
these diseases,” says Logan.
ON THE NOSE
In the f uture, an artificial nose might
be as simple as a patch that you wear on
your skin like a plaster, or a wristband
that changes colour when it detects the
chemicals in your sweat, or it could be a
smartwatch. It might even be a handheld
electronic nose – an e-nose – tailored to
sniff out the signature smell for the disease.
Prof Krishna Persaud, a chemoreception
expert at the University of Manchester, has
developed an e-nose that’s about the size
of an early mobile phone, and brings us
a step closer to what has until now been
science fiction. According to Persaud,
we haven’t quite managed to develop a
tricorder like the one used byStar Trek’s
Dr McCoy yet, “but we are looking at a
set of tools right now being developed
by researchers around the world, which
will help to transform medicine for the
future,” he says.
The e -nose work s by produci ng a
chemical f ingerprint af ter processing
signals from its ‘nose’ – the sensor. When
an odour hits the sensor it changes the
electrical signal. One type of sensor uses
a small quartz crystal that oscillates at a
frequency that depends on its mass. Incoming odour molecules
change the mass of the crystal and the resulting change in
frequency is measured.
Persaud and his team, however, are developing a new type
of sensor – one that more closely mimics what an animal’s
nose can smell. Using molecular biology, they’ve synthesised
proteins that are naturally present in the mucus of animals’
noses, where they bind to odours and carry them to the smell
receptors. The result is a super-sensitive bioelectronic nose
that has to learn to detect changes in chemicals that happen
when we get sick.
But another scientist wants to take it a step further, by putting
a nose in your phone. Dr Andreas Mershin, director of the
Label-Free Research Group at the Massachusetts Institute ofABOVE LEFT:This very
good girl is being trained
to identify the smells of
diseases
LEFT:Dr McCoy could
wave his tricorder over a
patient to diagnose their
ailments. We’re not quite
there yet, but the device
is becoming closer
to reality
ABOVE RIGHT:
Dr Andreas Mershin with
his prototype device he’s
developing that fits in
your phone and sni s
out cancer