Advances in on-skin devices to capture, store, and communicate data proliferated in the past two years. Health Tech Insider has covered temporary tattoos used to read blood alcohol content, check blood glucose levels, and monitor vital signs among other applications. Most temporary tattoos employ circuitry on the skin surface that look pretty cool, if your idea of fashion tends toward cyborg. MIT and Microsoft collaborated to change the look and expand the functionality of on-skin tattoos.
MIT Media Lab and Microsoft Research developed DuoSkin. DuoSkin enables the use of gold leaf for metallic temporary tattoos fabricated simply and rapidly. DuoSkin covers silicon tattoo paper holding embedded electronics with inexpensive conductive gold leaf. The process can function for both prototyping and final applications. The project enables three application classes: input; output; and wireless communications.
As an input mechanism, a DuoSkin metallic tattoo can sense touch. Example applications include functioning as a trackpad or media controller. This type of application obviates the need to carry a separate device. Using thermochromic pigments that change color with temperature, a DuoSkin tattoo could give continuous skin temperature readings. Another possible application suggested by Cindy Hsin-Liu Kao, an MIT Media Lab researcher involved with the project, uses color changes to indication emotional shifts. The third focal DuoSkin application, wireless communications, uses near field communications (NFC) to read data. One obvious use would be making payments by waving your wrist over an NFC reader.
According to Kao, creating a DuoSkin tattoo couldn’t be simpler, assuming suitable circuitry design already exists. The first step re-creates the circuit design with any graphic software followed by using a vinyl cutter to cut out the traces on silicon tattoo paper. After layering gold leaf on top of the conductive tattoo paper, thin surface-mount electronics are embedded in small holes in the tattoo paper and secured to the gold leaf traces. Details of the process are available in a PDF file.
The advantages of inexpensive, easily secured materials, durability, and straightforward fabrication combine with the aesthetic potential of gold leaf designs make DuoSkin a compelling technology for future Health Tech applications.