Thanks to developments in materials science and the availability of tiny off-the -shelf chip components, it is now possible to create cost-effective, ultra-thin, sophisticated electronics that stick to the skin and move and stretch with it. Scientists and engineers from Illinois describe their design for wireless health-tracking skin patches in the journal Science.
The medical innovation is the work of two teams led by John A. Rogers, a professor at the University of Illinois, and Yonggang Huang, a professor at Northwestern University, who says they designed the device to be able to monitor a person's health 24/7 without interfering with day to day activity.
"It is as soft as human skin and can move with your body, but at the same time it has many different monitoring functions," Prof. Huang explains. "What is very important about this device is it is wirelessly powered and can send high-quality data about the human body to a computer, in real time."
The team sees the patches being used for everyday health tracking. Without the need for wires, pads or tape, they stick on the skin like temporary tattoos, sending data wirelessly to your cellphone or computer.
They have already conducted a side-by-side comparison against traditional electrocardiogram heart activity and electroencephalography brain activity monitors, and found the patches performed as well as conventional sensors, while being a lot more comfortable.
Comfort is an important feature for applications like stress tests and sleep studies where patients have to wear sensors all the time and still move and behave naturally.
Another potential use is monitoring the health of patients with fragile skin, for example newborns.
Availability of off-the-shelf chip components makes the patch cost-effective
The group at Illinois University had already developed a skin patch using ultra-thin components that they custom-designed and printed. But this latest development uses ready-made, off-the-shelf chip-based components, which offer the same performance but at a much lower cost.
The patch itself is made of a thin elastic envelope filled with fluid. The tiny sensors, circuits, radios and batteries are suspended in the fluid and bonded onto tiny raised supports, allowing the underlying patch to stretch and move. You can see how this works in the video below.
Another neat feature of the design is that the wires connecting the components are folded like origami, so the whole unit can stretch and bend in all directions with the skin without damaging or being constrained by the rigid electronic components.
Better quality data than wristbands and clip-on devices
The researchers believe skin-mounted devices offer a much clearer picture of what is going on than wristband or clip-on devices, which are not as accurately coupled to the body and are plagued with background noise because they can only measure relative motion, as Prof. Rogers explains:
"If you have these skin-mounted devices and an ability to locate them on multiple parts of the body, you can get a much deeper and richer set of information than would be possible with devices that are not well coupled with the skin."
The researchers believe skin-mounted devices offer a much clearer picture of what is going on than wristband or clip-on devices.
He says this is just the beginning of what is possible in personal health care once you have technology that is "softly and intimately integrated onto the skin."
The researchers hope their technology will go beyond health tracking and also help identify problems before even the patient realizes it. For example, it might be possible to analyze motion data for signs of movement patterns that are consistent with Parkinson's disease and help detect it at the very early stages.
Funds from the National Security Science and Engineering Faculty Fellowship of Energy, the Korean Foundation for International Cooperation of Science and Technology, and the Department of Energy helped finance the study.
Meanwhile Medical News Today recently learned how developers at Google are working on a "smart contact lens" to help diabetics. The current prototype contact lens, which measures glucose levels in tears, incorporates tiny chips and sensors, and a miniature antenna to send the data wirelessly once per second. The Google team is also thinking of incorporating an LED light that flashes a warning when glucose levels get too high.
Written by Catharine Paddock PhD