As trendy as health-tracking bracelets may be, it might not be long before they seem as dated as dial-up Internet and as subtle as a boom box.
An even more sophisticated type of wearable tech is evolving quickly, one that while barely noticeable, could transform personal health care. It’s the electronic skin patch, and two studies published this month hint at what may be possible with this rectangle of soft, flexible material filled with tiny components. Able to stick to—and move with—a person’s skin like a temporary tattoo, the latest models show that these patches could provide a wide range of medical treatment—from gathering, storing and transmitting data about what’s going on inside a person’s body 24/7 to detecting when that person needs medication and then dispensing it.
Based on research published in the journal Science, a device developed jointly by engineers at the University of Illinois at Urbana-Champaign and Northwestern University could have a broad application, capable of tracking vitals and muscular activity, but also of monitoring symptoms related to a specific illness.
For instance, the lead scientists on the project, John Rogers at Illinois and Yonggang Huang at Northwestern, say their patch proved to be just as accurate as conventional equipment in recording EKGs of heartbeats and EEG readings of brain activity—which means that kind of data could be gathered without a person needing to get wired up in a doctor’s office or clinic. That, Huang points out, makes the patch particularly well-suited for situations where a doctor needs to collect data from a patient over a long stretch of time, such as when diagnosing sleep or heart problems, or conditions such as Parkinson’s disease.
The goal, he says, is to use “stretchable electronics” to continuously monitor a person’s health without them noticing it, and then have it send that information wirelessly to a computer or smart phone. This patch is the latest iteration of what Rogers, a leader in the field, has called “epidermal electronics.” He contends that components adhered to skin through a patch can provide a richer, more precise set of data than a wristband subjected to random movements.
The most ingenious aspect of the device is a design that allows sensors, capacitors and batteries to fit into a patch as thin as a human hair while still maintaining the flexibility to move with the skin. The key is the use of microfluidics—the patch is actually filled with fluid in which the components are suspended—and wires folded like origami so that no matter which way the device bends or stretches, they adapt to the motion. That flexibility has allowed the engineers to use cheaper off-the-shelf parts rather than the customized ones in an earlier version. And that makes this patch more commercially viable, although it’s still probably two years away from being available to doctors.
The other study, which appears in the April edition of Nature Nanotechnology, focuses on the research of a team in South Korea that has developed a somewhat different kind of electronic patch. It addresses a drawback of devices that provide a continuous flow of medication into a patient’s body. The problem is that these drug-delivery systems have no way of checking a patient’s vitals, so they dispense the same level of medication no matter his or her current condition.
Sensors in the patch created by engineers at Seoul National University can, based on tension and compression of muscles, determine when drugs are needed and when they’re not. For example, when a Parkinson’s patient starts to have tremors, the patch can pick up on the motion and distinguish it from normal arm movements, then deliver the necessary drugs. Same thing when someone with epilepsy has a seizure. The device can also store data that can help doctors spot patterns and see how patients respond to medications. The prototype focuses on treating motion disorders, but the researchers say the patch can be adapted to track things like perspiration, temperature, heart rate or blood oxygen levels and use that data to trigger treatment of other conditions.
The researchers acknowledge that their patch is still years away from coming to market. It still doesn’t have the capability to wirelessly transmit the data it captures and stores to another device. But it does add another dimension to what these devices can do. Now a single, two-inch wearable patch can diagnose a condition and treat it.
What they’re wearing
Here’s other recent news on health-tracking devices:
Gut instincts: Researchers at Mount Sinai Hospital in New York are studying whether a patch could be used to treat Crohn’s disease. It’s still not clear what causes the inflammatory bowel disease, but scientists want to see if they can retrain the immune system to work properly by delivering T cells to the gut.
An Apple a day: According to the website 9to5Mac, which tracks what’s going on behind the scenes at Apple, the company is going to plunge into the health-tracking business this fall with the launch of an app called Healthbook. The app will reportedly be able to track all kinds of personal data, including physical activity, heart rate, blood oxygen level, blood pressure, hydration levels, blood sugar and sleep patterns.
The heat is on: A company called the Silent Herdsman has developed a collar for cows that can monitor their behavior and let farmers know such important things as when they're in heat.