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[IP] tiny insulin pumps

I found this on The Islet Foundation:  <A 
HREF="http://www.islet.org/forum/messages/10097.htm">OSU, "insulin pump" and 
Al</A> Message board

Ohio's Greatest Home Newspaper
OSU developing implant capsule to fight diabetes 

Tiny insulin pumps 

Thursday, September 30, 1999

By David Lore
Dispatch Science Reporter 

Mauro Ferrari, director of the OSU Biomedical Engineering Center, is 
perfecting an insulin pump that once implanted in patients could 
eliminate daily injections.-->

Imagine an armada of hundreds of thousands of microscopic silicon 
capsules, each no thicker than a human hair but capable of becoming a 
tiny insulin pump inside the body of a diabetic.

Such microfabricated biocapsules are the newest weapons being tested at 
Ohio State University in the war against diabetes.

It could be five years before the technology is ready for large-scale 
medical trials, but Mauro Ferrari, the inventor, is confident that the 
capsules will prove to be a significant breakthrough.

"I think he's onto something which is truly creative,'' said Alastair 
Gordon, president of the Islet Foundation in Toronto, which supports 
diabetes research. "One can't say for certain this is the technology 
that will cure diabetes, but it's promising and deserves support.''

Ferrari developed and patented the concept in 1993 while at the 
University of California at Berkeley. He became director of the OSU 
Biomedical Engineering Center last year.

His approach is that, in developing a capsule to protect 
insulin-producing cells from the body's natural defenses, size matters.

"If you can't beat the immune system,'' he said, "you hide from it.''

In Type 1 diabetes, the immune system has destroyed the body's natural 
insulin-producing cells, which are needed to metabolize glucose or blood 
sugar. Gordon said 1.6 million American diabetics need daily insulin 
injections to keep their blood sugar in balance.

Each of Ferrari's capsules would contain several hundred to several 
thousand pancreatic cells. The capsules would be riddled with holes so 
the cells could monitor glucose levels and produce insulin as needed. 

Hundreds of thousands of these capsules could be contained within a 
polymer sack no larger than a grape. The sack would be surgically 
implanted under the skin, where it could function for months, 
eliminating the need for daily injections.

The problem with this approach, Gordon said, has been that antibodies -- 
the body's natural defense system -- enter the capsule and kill the 
cells within a few days.

Ferrari's solution is to apply the technology used to create microscopic 
circuits on computer chips. This allows precise engineering of tiny -- 
only about 30 atoms across -- and uniform holes in the capsule wall.

"It's a little bit like a screen door,'' Gordon said. "A screen door 
lets fresh air in but keeps the insects out. This immuno-barrier allows 
critical small molecules such as oxygen and glucose in and allows the 
insulin to get out. But it keeps out the antibodies.''

Previous attempts to build capsules from plastic failed because the hole 
size was inconsistent, allowing in some antibodies.

The computer industry, however, already knows how to cut holes in 
silicon only a few atoms in diameter and make them all the same size.

"If we want to make 18-nanometer holes, we make 18-nanometer holes, 
millions and millions of them, all exactly the same,'' Ferrari said.

A nanometer is the size of three or four atoms; it takes a billion of 
them to make a meter.

Animal tests are under way to make sure that silicon can be used safely 
inside the body and that the insulin flow won't be blocked by the 
natural fibers that wrap around any transplant.

The biocapsules, Ferrari said, also might be used for pain control and 
disorders such as hemophilia and Alzheimer's disease.

Ferrari expects Ohio State to become a major player in biomedical 
engineering as the center expands into a full department during the next 

"Everybody is getting excited about biomedical applications, but 
actually we're one of the fastest programs to develop,'' he said. "The 
expectation is that Ohio State will have one of the top three programs 
in the country in five years or less.''

Much of that depends on research support from industry and venture 
capitalists, he said. The biocapsule work is supported through a $1.4 
million grant from the Ohio Board of Regents.

"It's a tough area for funding,'' Gordon said. "The market caps are 
certainly not at the level they are with Internet start-ups. But I think 
Ferrari could enter human trials sooner than five years. You could test 
this on 10 people and know if you have a winner.''
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