Temporary tattoos might soon be replacing heart rate monitors and other traditional medical devices, as a new manufacturing process is enabling tattoos that sense critical medical information to be easily created.
University of Texas Professor Nanshu Lu and a team of colleagues have managed to create a method for quickly producing cheap and effective wearable biosensors. Previously, such technology was difficult, tedious and expensive.
The purpose of these tattoos is to monitor a person’s health during a temporary period.
Lu says, “Ultimately, if you think about tattoo-like electronics, no one wants to reuse them, not even on yourself. So the disposable nature is key.”
The old manufacturing process of similar devices involved integrating a metal circuit with a stretchy adhesive. Such a method was not worth the effort involved.
Lu and her team examined various methods for making such electronics flexible and sticky. By using concepts related to 3D printing, the team determined a way to utilize a mechanical cutter for the purpose of carving out patterns on a sheet of metal rather than forming the electronics in a mold.
Lu explains, “We started to look for metal sheets deposited on polymer sheets, basically like aluminum foil laminated onto double-sided tape. We invented a process that can form cutting patterns onto those sheets, then remove the unnecessary parts. The leftover part is transfer printed onto medical tape or tattoo adhesive.”
Printing one of these medical tattoos takes about 20 minutes. The amount of waste created is minimal, and the process does not require a specialized laboratory. Lu says that she has the goal of bringing the cost of a single patch down to $1.
The patch is roughly the size of a credit card, and it is able to monitor the vital signs of a patient for about one week. Based on the body’s location of the patch, it would be able to function in several different ways.
In the future, Lu hopes that the patch will be able to wirelessly communicate with the electronic devices of the doctors in order to relay information quickly. However, Lu is facing challenges in making the patch able to communicate wirelessly. Lu and her team are currently working on creating a wireless chip that is only two square millimeters in size.
The team expects that the patch will be ready for use in the near future.