2. Centrifuge replacement is toy-inspired—and costs less than 25 centsA centrifuge can cost hundreds of dollars, weigh several pounds and consume lots of electricity. What if there was a toy-inspired device that drastically reduced the price, energy consumption and weight and was completely powered by human force? The whirligig-inspired Paperfuge does just that, weighing 2 g and costing less than a quarter to produce.
Stanford bioengineers have developed a human-powered centrifuge that can reach rotational speeds of 125,000 rpms and isolate malaria parasites in a matter of minutes.
The way the Paperfuge works is simple. The user inserts a capillary of blood into a pocket in the center of the paper disc. They grab the looped ends of the attached twine and start rhythmically pulling. The twine will coil and uncoil while the disc starts rotating in an oscillating fashion at high speeds. It’s the similar motion that comes when you release a yo-yo and bring it back to you without returning it to your hand.
Using 20 cents worth of paper, twine and plastic, the Paperfuge can exert centrifugal forces of 30,000 Gs with its 125,000 rpms.