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Devices for Diabetics Expand Inward and Outward

Advances in continuous glucose monitors and data networking bring us that much closer to having an artificial pancreas

2 min read

Funding and advising the development of an artificial pancreas is a major long-term initiative at the FDA. A couple interesting advances have recently been made, both commercially and in research, that seem to bring us closer to this goal.

According to the FDA, an artificial pancreas would consist of three components:

"(1) an infusion pump to deliver the required drug, many of which are already available; (2) a continuous glucose monitor, several of which have been approved by the FDA for tracking and trending glucose levels; and (3) an algorithm to communicate between the pump(s) and glucose monitor. An algorithm will receive information from the glucose monitor and convert it to instructions for the infusion pump."

Some continuous blood glucose monitoring devices are already available on the market (here's a good comparative chart).  All give periodic updates of blood glucose levels measured from a sensor inserted just beneath the skin. But all fall short, in some serious way or another, of what an artificial pancreas would require.A huge problem, it seems, is the lifespan of the device. The sensors for these models only last a few day and have to be reinserted regularly. Furthermore, the sensor is only partially implanted, and connects to a transmitter through the skin.

Last month, engineers at the University of Calgary published an alternative design that mounts a glucose sensor onto a transponder chip. An external reader inductively powers the chip while reading the glucose level, eliminating the need for it to hook up to a battery powered transmitter. This makes the  device very small, and thus more durable in the body. Removing the need for a battery also means that the entire chip and sensor can be fully implanted under the skin.

The design also uses an alternative chemical reaction to measure the glucose levels in the body, one that doesn't require oxygen. The oxygen-driven reaction used by other devices produces hydrogen peroxide that can corrode the sensor.

The device hasn't been tested in an organism yet, and once that happens it will be interesting to see how accurate it actually is, but these are definitely ideas that could improve available models.

Another thing that is changing is the extent to which these glucose monitors can communicate with computers and other devices. The MyGlucoHealth system uses a traditional pin prick glucose meter but has installed it with a USB cable and bluetooth capabilities that make it possible to synchronize data with a diabetes management system. It also keep doctors and patients up to date with individuals' glucose level fluctuations with text messages and email. This kind of network is likely to be vital in a system that closes the loop with an automatic insulin infusion pump.

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