The inspiration for a portable, powerful chemistry set came not from cloud computing or nanotechnology but a decidedly old-school source: a toy music box. The handheld device could be used where electricity and hospitals are scarce, allowing things like water testing and making medications.
Stanford assistant professor of bioengineering Manu Prakash was struck by the idea when its wife brought home an old music box that used perforated paper to create a melody. By turning a crank, the paper is drawn through the device, and when a hole in the paper is encountered, a pin inside spins and plucks at a metal strip, creating a tone.
But what if each pin, Prakash wondered, were to instead release a tiny droplet of a certain chemical?
With the help of graduate student George Korir, Prakash managed to pair the music box mechanism with a more modern technology called a microfluidic chip. This uses tiny channels etched in silicon to deliver precise amounts of fluids stored elsewhere on the chip — but generally require powered electronics to use, driving up the cost and difficulty of deploying them.
When combined with the music box, however, the channels can be activated with the pins which once struck notes, instructed by paper sheets just like those that once let it play "Happy Birthday."
The chemical chips and paper sheets can be exchanged and refilled, allowing a variety of chemical tasks that require high precision: water purity testing, venom identification, even the synthesis of simple medicines. It could even be used in labs — or by curious kids.
Developing communities won't have to go hunting around for old music boxes, either: Prakash and Korir are working on allowing much of the device to be created in a 3-D printer, and the whole kit can be made for under $5.
Prakash's work won his lab a $50,000 award from the Science Play and Research Kit Competition, and he is working on developing it for more widespread deployment. You can watch the device in action below.