Diabetes care is a source of limitless innovation, with a modern focus on automatic systems like 'smart' insulin patches or wearable devices that fully replicate the functions of the pancreas. But these technologies don't happen on their own. They're made possible by a collage of component technologies, like microfluidics, the technology that makes it possible to test glucose levels with a prick of the finger and a portable device, rather than a trip to a lab for blood work.
Microfluidics, as the name implies, deals with small amounts of fluid—in this case, using a tiny amount of blood from a finger prick is enough to complete a blood test. A microfluidic strip, like those used in glucose testing, consists of an extraction site, one or more test sites, and hydrophilic channels between.
Hydrophilic (water-loving) surfaces attract water, causing it to flow evenly across the surface instead of beading up in one place. In the case of a blood glucose test strip, there is a tiny hydrophilic channel that routes blood from the extraction site to test chamber, the same way that copper surfaces route electricity across an electronic chip.
Once the blood reaches the test chamber, the test itself works in an ingenious way. The blood sugar reacts with chemicals and enzymes in the test chamber, resulting in an electrochemical charge whose strength is directly connected to how much glucose is in the blood. An electrode in the test device senses this electrical charge, allowing the device to determine how much glucose there is in the blood.
The most common use of this technology today is the portable glucose test meter, but that's only the beginning of what the technology can do. Glucose testing by a meter is limited by the single use of each test strip, and the performance of the enzymes. But as the technology advances, applications like automatic insulin administration or continuous blood testing may become possible—which will help those living with diabetes lead even more normal lives.