Manu Prakash, professor of bioengineering at Stanford University, is responsible for creating a range of astonishingly advanced pieces of scientific equipment at bargain basement prices. His latest impressive feat? A so-called “paperfuge” centrifuge based on a classic children’s toy, the whirligig.
A centrifuge is a piece of equipment that rotates an object very rapidly around a fixed axis, thereby separating out cells of different weights so they can be studied. They are frequently used in labs for analyzing everything from blood to stool samples. As with a lot of specialized laboratory equipment, however, centrifuges can be expensive, and they require electricity to work.
Neither of those two limiting factors are true of Prakash’s creation, which is nonetheless able to hit an astonishing 125,000 revolutions per minute — thereby providing the necessary centrifugal forces. To build it, all Prakash and his team required were two circles cut out of paper, Velcro brand-style hook and loop fastener to attach tiny tubes, wooden handles, and two strands of wire to connect them.
By separating the handles, the blood samples are given the kind of high-end spin treatment normally only achievable in a lab. The results potentially enable access to an important piece of equipment, usable as a diagnosis tool, all over the world.
The hand-powered ultra-low-cost paper centrifuge project is described in a paper, published in the journal Nature Biomedical Engineering. It details how Prakash and colleagues used it to separate malaria from infected blood samples in just 15 minutes. You can check it out here.
And, hey, once you’re done reading it, you can get some string and make a working centrifuge of your own!