New developments in materials, bio-engineering techniques and other disciplines have recently taken the concept of artificial organs from fantasy to reality. EU 346 PANART-Artificial Pancreas, for example, aims to develop an implanted artificial insulin delivery system, which promises to give diabetes sufferers a more normal and healthy lifestyle.
Diabetes occurs when the pancreas is unable to adequately regulate insulin levels in the bloodstream. The artificial pancreas will operate quite independently from the natural pancreas, which need not be removed. “It is situated just below the liver in the peritoneal cavity in the abdomen,” Mr. Ellingsen, the device’s inventor, explains. “This cavity is filled with peritoneal fluid-or blood without the red and white blood cells-which accurately reflects the body’s glucose level.”
The device consists of an insulin reservoir, a complex system of valves and pipes and a chamber filled with a liquid of the same chemical balance as the peritoneal fluid. “Part of the chamber’s wall is a semi-permeable membrane,” continues the Norwegian inventor, “which means that whenever there is a chemical imbalance between the two fluids, one flows across the membrane into the other.”
Thus, every change in the diabetic’s glucose level triggers a fluid flow in one direction or the other, which in turn opens or closes the valve connecting the insulin reservoir to the body. Whenever insulin is needed, the valve is opened and the life-giving drug is administered. And whenever the body has had enough, the valve is closed, ensuring that the recipient gets just the right amount.
The reservoir can contain enough insulin for fourteen days, and is easily refilled by syringe by the user. The entire device is implanted in a simple surgical operation lasting no more than 15 minutes, and is expected to last three years. According to Mr. Ellingsen, “It should make an enormous difference to diabetes sufferers. Imagine only having to resupply a reservoir once a fortnight, instead of your blood every day.”
Biocompatibility: An Essential Element
The above description omits many crucial elements, such as the titanium structure that supports and shelters the membranes from interaction with tissue, proteins or other elements in the human body. These and other components highlight the need for “biocompatible” materials, substances that will generate little or no reaction from the body.
This is one of PANART’s primary technical challenges, and has focused considerable attention on plastic membrane technology. The quality and characteristics of the insulin are other highly important issues.
Lifecare A/S provides the focal point for this work. The University of Trondheim in Norway provides academic and research support, while Scandex International of the United Kingdom contributes its know-how in plastics technology. The project also has close connections with research institutes in the U.S. and Spain, while a Danish hospital supplies information on medical requirements.
Mr. Ellingsen is eager for new partners to get involved. He would particularly like to see the entry of a large European company capable of manufacturing the end product. The size of the potential market for the artificial pancreas is large: there are 160 million diabetes sufferers worldwide. He anticipates that the complex medical product will initially be marketed in Europe, particularly in the country of manufacture.