Posted by James on October 21, 2002 at 12:42:14:
Keeping insulin warm in Antarctica
Industrial design student creates special gel packs to protect diabetic's insulin during a South Pole trek
Monday, October 21, 2002
By Byron Spice, Post-Gazette Science Editor
If you take a long walk across frigid Antarctic wastes, you've got to expect that something might freeze by the time you reach the South Pole. And if you're a diabetic like Will Cross, you make sure that the last thing that freezes is your insulin.
Frozen insulin is ruined insulin, so Cross, 35, will take extraordinary measures to protect his insulin during a 730-mile trek to the South Pole, which the Morningside resident expects to begin early next month from Hercules Inlet near Antarctica's Patriot Hills.
For the past seven months, he has worked with Michael Duda, a 21-year-old industrial design student at the Art Institute of Pittsburgh, to design a system to protect his three-month supply of insulin without using electrical or mechanical parts that might fail in minus-30 degree temperatures. And, because Cross needs to carry or pull his supplies all the way to the South Pole, it all needs to be as light as possible.
Duda's solution is a system he calls the Insulinator, a series of nylon-and-Velcro insulating sheaths that wrap around each of the 20 insulin injector pens that Cross will take with him.
The insulation in each sheath is a substance called aerogel, a material so light and airy that it is sometimes described as frozen smoke. This makes aerogels the next best thing to a vacuum and, thus, a terrific insulator.
Aerogels have been around for seven decades, but typically are as fragile as they are light. For this application, however, Duda was able to obtain flexible, one-centimeter-thick aerogel blankets manufactured by Aspen Aerogels Inc.
Kang P. Lee, chairman and founder of the Marlborough, Mass., company, said the insulating ability of aerogels is four or five times better than that of fiberglass, and twice as good as the best plastic foam.
Conserving every bit of heat will be important as Cross and his travel partner, Jerry Petersen of Jefferson Hills, make their way across the frozen continent.
"It's just critical that the insulin not freeze," said Cross, who on Saturday will fly to Chile and, as weather permits, on to Antarctica.
The expedition, called the Novolog Ultimate Walk to Cure Diabetes, is intended to raise money for diabetes research while also providing data on how a diabetic body responds to stress. Cross and Petersen will begin their walk early next month, with hopes of reaching the South Pole sometime between New Year's and Jan. 20.
During a 2001 trek to the North Pole and a Greenland trial run in July, he kept his insulin pens warm by storing them inside his long underwear. But the South Pole trek will last at least 60 days and that will require more insulin than he can practically carry inside his clothing.
He'll share his sleeping bag with the insulin every night and he has room for three Insulinator-wrapped pens inside his parka. But during the daily 10-hour walks, most of the insulin pens will end up stuffed inside the sleeping bag and carried with other gear on a sled that Cross will pull. Keeping that insulin from freezing will be a challenge.
Cross, a Pine-Richland School District teacher, had approached the Art Institute for help in solving his insulin dilemma, aware that its design students for several years have been involved in projects to design apparel and even a bicycle for use by scientists in Antarctica.
"This is the essence of what industrial design is about," said Bill Farrell, Duda's faculty adviser. "It's not just TV sets."
"We don't just draw pretty pictures," agreed Duda. "We're problem solvers."
Duda, who recently graduated with his bachelor's degree, had previously designed toys and a device pediatricians can use to distract babies. But he found that the insulin project was both personally meaningful -- his mother has diabetes -- and technically intriguing.
"It's easy to draw a pretty picture and say it will work," he explained. "But to actually make it work is an unbelievable challenge." It was a solo project for Duda, as well as his senior thesis, and something of an obsession. "It more or less became my life after awhile."
He tried and discarded several ideas, including a package with a hard, Kevlar-and-resin outer shell that Cross would have worn in the small of his back. The lower backpack wouldn't have interfered with the harness Cross will wear to pull his 150-pound sled and also would have taken advantage of heat from his back. But it proved awkward to use and would have been of little use when Cross wasn't walking.
The final design allows Cross to inject himself without ever taking the insulin pen out of its insulation.
Cross said he has no qualms entrusting his life-sustaining insulin to Duda's invention, which is undergoing final testing this week.
"I've seen how hard he's worked on it," he explained. "It's not something he's rushed. That level of commitment is important when you go someplace like the Antarctic."