(Almost) Ready to Wear

Wearable tech research boosts comfort, efficiency, and exciting new applications.

Medical Monitoring Made Easy

1. BLOOD PRESSURE: Roughly the size of a nickel, this stick-on patch is embedded with dozens of tiny electronics that send ultrasound waves through the body to measure central blood pressure, or CBP. Not to be confused with blood pressure measured by a simple cuff, CBP is the pressure found in the body’s central blood vessels that send blood directly from the heart to major organs. CBP must be continuously monitored in patients who are critically ill or undergoing surgery, but traditional methods involve a catheter inserted through the arm, groin, or neck and guided into the heart—an invasive process that can cause complications. This patch does a similar job, all from the surface of the skin.

2. BLOOD SUGAR: An estimated 30 million Americans live with diabetes—and with three blood sugar tests a day, that’s nearly 1 billion daily finger pricks in the U.S. alone. Researchers at UC San Diego aim to subvert the sting with a wearable sensor that can painlessly and continuously measure the level of blood sugar through the skin. The device is applied just like any temporary tattoo, but its two electrodes produce a mild electrical current that forces glucose molecules between skin cells to rise to the surface. A built-in sensor then translates the strength of the electrical charge to determine overall blood sugar level. This sensor may well be the first to make the leap from the lab—the tattoos are now being tested in a Phase 1 clinical trial with UC San Diego Health.

Building a Better Battery

3. SWEAT POWER: If your wearable device is ever running out of power, don’t sweat it—or in this case, do. This stretchy skin patch could power wearables through a user’s own body sweat. The patch contains an array of small biofuel cells equipped with enzymes that trigger reduction and oxidation reactions—a swapping of electrons between molecules that generates electricity. This device performs such reactions on the lactic acid of human sweat to generate current, while a supercapacitor stores the energy produced and releases it as needed. An early patch prototype can light up a small LED for as long as the user is sweating.


4. STRETCHY BATTERIES: Hi-tech apparel may sound enticing, but being tethered to a battery pack doesn’t seem so ideal. So UC San Diego researchers have developed a flexible, stretchable battery that’s rechargeable and can even be printed directly onto garments or stick-on patches. Made from ingredients found in rubber and other common materials, prototypes of the battery have been seen to stretch twice in size in any direction without suffering damage. The batteries can power a small LED, and because they are screen-printed, they are relatively inexpensive to make (about 50 cents each, compared to a relative rechargeable battery at $5). Researchers are working on bringing the battery to market via the UC San Diego spin-off company, Ateios, which has three alumni at the helm (read Q&A here).