It wasn't that long ago that you had to go to your doctor's office to measure most of your vital signs.
But now, you can buy wearable devices that measure your blood pressure, or even record the electrical activity of your heart.
So what's next? UC San Diego's Center for Wearable Sensors offers a glimpse.
The future of wearable medical devices
Inside the center's nanoengineering lab, a mannequin is covered with colorful tattoos. Meet the next generation of wearable sensors.
There’s a sensor that measures the body’s metabolic functions, or one that monitors pH levels. Center Director Joseph Wang said all of their prototypes rely on electro-chemical detection.
“What’s unique about us is we can measure chemical markers," he said. "Many of the wearable devices measure calories, steps, but no chemical information.”
Wang’s team of researchers is developing sensors that can measure someone’s potassium or lactic acid levels through their sweat or saliva. Currently, the only way to do that is with a blood test.
Or, how about this: a tattoo-like sensor that gauges someone’s blood glucose level without using a needle.
“There is a good correlation between the glucose levels in the interstitial fluid, which is the fluid just below the skin, and blood glucose," doctoral student Amay Bandodkar said. "So what we can do is non-invasively extract the glucose to the surface, without anything penetrating in the skin.”
If it eventually goes into production, this device could be a major breakthrough for the more than 370 million people worldwide who have diabetes.
Bandodkar points to another invention he and his colleagues developed. It looks like a mini-decal with the initials UC.
“It’s the acronym for the University of California," Bandodkar said. "But it is actually a functional biofuel cell that can generate electricity from the sweat. And we recently showed that just by sweating, the amount of electricity generated can power an LED or even a wristwatch.”
The power challenge
The biofuel cell gets to the heart of one of the major challenges facing wearable devices: how to power them.
That challenge is being tackled in a different lab in the school of engineering, run by Patrick Mercier, the co-director of the Center for Wearable Sensors.
Mercier thinks consumers don’t want to be weighed down with battery packs, or have to recharge the devices every day.
“So how do we do the sensing we want to do, but at a very, very low power, so that we can have battery life that can last for not just days, weeks, and months, but years?" he said. "Or, in the best case, we harvest energy from our environment, so that we don’t need batteries at all, and they just last essentially forever.”
Wearable technology ready to take off
Either way, the market for wearable technology looks like it’s getting ready to explode.
A report from the financial services company Credit Suisse predicts the global market for wearable devices will increase tenfold by 2019.
The San Diego-based Wireless-Life Sciences Alliance is a trade group that focuses on the digital and wireless health industry. CEO Rob McCray said San Diego is well positioned to take advantage of the industry’s growth.
“It’s a world leader in wireless telecommunications, so that’s one foundation," McCray said. "It is one of the world leaders in the life sciences. It is the world leader in genomic companies.”
McCray said wearable devices have the potential to help change the way we handle chronic conditions like diabetes and hypertension.
“We are putting tools that enable people to take better care of their own health, and even provide management of their own healthcare," he said.
Still not ready for prime time
The next generation of these tools, like the non-invasive glucose-measuring tattoo, isn’t ready yet. There are still some problems to be solved.
But doctoral student Amay Bandodkar thinks it might not be too long before keeping track of your blood sugar will be as easy as putting on a Band-Aid.
“Not only interesting from the science point of view, but also from humanity’s," he said. "I mean, the impact that’s it’s going to have on the world population is going to be amazing.”
That would depend on whether people with diabetes would buy such a product.
According to a recent survey from the Pricewaterhouse Coopers Health Research Institute, 21 percent of survey participants owned a wearable device, and only 10 percent used one every day.
