Patients who rely on the use of coagulants to limit the formation of blood clots in their veins also require frequent and regular trips to the hospital for tests to monitor their blood flow. It's a time-consuming side effect that researchers at EPFL hope they've solved with a portable test that relies on a smartphone's display's unique properties.

Namely, the fact that a capacitive touchscreen actually maintains a constant electrical charge. It's not strong enough to be felt like a shock, but every time your finger touches the screen it disrupts the charge, letting the phone's hardware pinpoint exactly where the interaction occurred. It's also why only a stylus that can conduct an electrical charge works, and how this home blood test was made possible.

The blood test looks like a simple thin film, but it's actually made of a highly-engineered plastic layer that's just a few micrometers thick. When a drop of blood is introduced, it interacts with a special molecule that initiates coagulation. And as the blood coagulates, it disrupts the touchscreen's constant electrical field in a very specific way which can then be analyzed by an accompanying app.


The results can also immediately be sent to a physician who can diagnose if the patient's medication is still correct, or if the dosage needs to be adjusted. And while the film is still in the research stage at this point, its creators are hoping to have it perfected for a 2015 rollout, assuming, of course, that some other miraculous technology doesn't completely supplant capacitive touchscreens in the coming year. [EPFL via]