Dino Di Carlo

In a hospital, blood from a finger prick usually goes to the lab, and the result comes back the next day. The new method promises to cut that wait to a few minutes. Instead of catching light reflected off a sample, it reads the electrical voltage that arises at the boundary between two media, like the faint tingle you feel when you touch a battery with wet fingers.

A drop of blood from a fingertip lands on the white membrane of a cartridge. Twenty minutes later, the phone shows whether Lyme disease is present or not. No test tube, no centrifuge, no waiting for days. Usually, for such a test, blood is first spun in a centrifuge to separate the liquid part — the plasma.