People who are prone to bleeding due to poor blood clotting, such as those with hemophilia or on anticoagulants, are often required to take blood tests. These test are usually done in clinics and hospitals, adding to the patient’s burden and expense of extra travel just to make sure that blood is adequately anticoagulated. New technology that is being developed at Qloudlab, a startup based at École polytechnique fédérale de Lausanne (EPFL) in Switzerland, uses capabilities already present in today’s smartphone screens for blood coagulation testing.
The system works by first applying a microfluidic plastic sticker to the surface of the screen which has tiny channels that allow blood to pass. A sample is taken and passed into the sticker, much like how diabetics test for blood glucose. A chemical that initiates clotting is then added to the blood, which in turn is sent through the microchannels within the sticker. Because modern smartphones use capacitive technology to detect when and where they’re being touched, they can be harnessed to detect how blood moves through the microchannels on their surface. The localized electric field on the screen changes as blood flows past, and the phone detects it as touch, but a complementary app developed at Qloudlab interprets these signals and provides a reading of blood’s coagulation.
