After adding a sample, such as blood, the user selects a punch card for a given reaction and cranks it past gears with teeth.
As one tooth slides into a punched hole, another squeezes a fluid channel to pump a chemical through a removable microfluidic chip.
Punched holes can also trigger the release of a single droplet, for precise volume control.
Up to 15 different chemicals react with one another as they travel along channels etched on the chip.
The user examines the results via embedded lenses that magnify images hundreds of times.