A chemistry professor at Harvard University is trying to shrink a
medical laboratory onto a piece of paper that's the size of a
fingerprint and costs about a penny.
George Whitesides has
developed a prototype for paper "chip" technology that could be used in
the developing world to cheaply diagnose deadly diseases such as HIV,
malaria, tuberculosis, hepatitis and gastroenteritis.
The first products will be available in about a year, he said.
His
efforts, which find their inspiration from the simple designs of comic
books and computer chips, are surprisingly low-tech and cheap.
Patients
put a drop of blood on one side of the slip of paper, and on the other
appears a colorful pattern in the shape of a tree, which tells medical
professionals whether the person is infected with certain diseases.
Water-repellent
comic-book ink saturates several layers of paper, he said. The ink
funnels a patient's blood into tree-like channels, where several layers
of treated paper react with the blood to create diagnostic colors.
It's
not entirely unlike a home pregnancy test, Whitesides said, but the
chips are much smaller and cheaper, and they test for multiple diseases
at once. They also show how severely a person is infected rather than
producing only a positive-negative reading.
The paper chips are expected to be used
in concert with mobile phones, which are exploding in popularity in the
developing world.
Since people in remote parts of Africa and
Asia often have to travel great distances by public transit or foot to
reach a medical clinic, patients simply can take photos of the chips
with cell phones and then send them to larger cities for diagnosis. And
Whitesides said his group
is also working with a cell phone maker to develop apps that would tell
patients the results of their tests automatically if doctors aren't
available.
"Doctors are as scarce a resource as money is," he said.
The
tests may also be useful for highly contagious diseases such as
hepatitis C, which require sick people to be quarantined to prevent
further infection.
Whitesides'
work, if successful, will bolster the argument that solutions to
complicated problems often are found in simple, low-cost technologies.
From
consumer electronics to medical equipment, a growing number of people
seem to be searching for technologies that are cheap, reliable and even
somewhat retro. Computer operating systems are being stripped of new
features in favor of a simplified experience; basic devices such as the
Flip cam seem more chic and popular than high-end video equipment.
The
spiking costs of health care in the U.S. put pressure on doctors to
perform expensive tests with high-end equipment only when necessary.
And in the developing world, the medical community has realized there's
not always electricity to power and doctors to manage high-tech medical
clinics with rooms full of electronics and labs.
Cheap and
reliable health care technologies are what the developing world and the
Western world need, said Dr. Gaby Vercauteren, coordinator of
diagnostics and laboratory technologies at the World Health Organization.
"Obviously
smaller, easy to use, inexpensive technologies will find their way
throughout the whole system and will provide better access to care to
all those who need it," she said.
She said many medical
diagnostic tests are too expensive for people in poorer areas of the
world to afford. But they are the essential first step to health care.
"Today,
many people don't get the necessary diagnosis that will lead to access
to the right treatment because diagnostic tests and lab tests are, most
of the time, out of pocket," she said. "People don't have the money to
buy that. Therefore, often, diseases are not diagnosed or only
diagnosed far too late."
Keith Herold,
an associate professor of bioengineering at the University of Maryland,
said Whitesides' ideas build on a branch of science that's trying to
develop "lab-on-chip" technologies, which use credit-card size devices
to perform laboratory analyses.
Whitesides' paper chips are
much simpler than other lab-on-chip projects, many of which require
intricate production methods and heavier materials such as glass and
plastic. But simpler might be better in this case, he said.
"I
think it's real. It can be very useful, but it's not the fanciest
manifestation of lab on a chip by any means," he said. "If it works and
it's cheap, it's good for everybody."
Still, Whitesides' paper tests could run into some pitfalls.
Vercauteren,
of the WHO, said the paper may mold in humid, hot climates. And it's
still important for people to get access to doctors so they know what
to do about their diagnoses, she said.
She said its possible to conquer those challenges.
The
first test, Whitesides said, will be designed to detect liver function,
which is important for people with HIV and who are on some strong
medications.