By Eric Peterson | Jul 11, 2022
RF-based temperature sensors
A longtime leader in RF science at the University of Colorado Boulder, Popovic was one of the inventors behind the wearable sensor LumenAstra is now commercializing.
Her Microwave and Radio Frequency Research Group developed the now-patented technology to accurately internal body temperatures below the skin.
The idea stemmed from a problem the U.S. military was having trouble detecting: potentially fatal heat stress. "They were having soldiers drop dead in Afghanistan due to heat stress," says Pollock. "You've probably also heard of football players in Tennessee and Texas dropping dead on the field at practices."
While others struggled, Popovic's group found a solution rooted in RF telescopy. "We realized if we work in the near field, the regular things that apply to the far field don't apply," she says. "We can sense at a depth inside the body."
Pollock, a self-described "high-tech geek," calls LumenAstra a return to his roots. "I did a little volunteer thing at the Tech Transfer Office at University of Colorado, where I was called entrepreneur-in-residence. I worked with faculty that had patents, ideas, and inventions to figure out: Is it commercializable? How would you go about commercializing it?"
LumenAstra's wearable sensor "is like a bandage you can stick anywhere on your body and it'll measure internal temperatures several centimeters below the skin," says Pollock. "It's a very tiny radio telescope that's aimed three centimeters into your body instead of 10,000 light years away, figuring out the temperature of a star. . . . So we can directly measure brain temperature, which is impossible to do without cutting into the skull. We can measure tumor temperatures, circadian rhythm for fertility prediction. There's a lot of interesting applications coming out of it."
"Everything -- stars, galaxies, the chair you're sitting on, your body -- everything radiates electromagnetic radiation proportional to the temperature," he adds. "We lower that frequency way down to the gigahertz range and now we can actually see several centimeters into the body."
The company built the first lab prototype in summer 2021 and has since iterated it to about the size of half of a credit card. "We're at the point where we're going to have a real prototype out this summer and start making some measurements on some people in surgical settings," says Pollock.
LumenAstra is targeting 2023 for FDA approval. Pollock says the first market will be for aortic repair surgeries -- low brain temperature is critical to the procedure -- then the company will then target intensive care units.
The company has three full-time employees and also works with a team of five Ph.D researchers in Popovic's at CU. It currently relies on a local manufacturer for initial printed circuit boards and sources semiconductor wafer from Taiwan. As volumes increase, "We'd like to stay as local as we can on the board level," says Pollock. "We have to go out to Taiwan on the semiconductor level."
"Our strategy is to build a sensor component, and we can either build it ourselves into a standalone device or we can sell it to a manufacturer that integrates it with other components," says Pollock.
Challenges: "We're listening to extremely small signals . . . and we're completely surrounded by microwaves that could interfere with it -- your cell phones, GPS signals from satellites, or if someone turns a microwave oven on," says Pollock.
"We think we have a pretty good handle on it. That's why really nobody else has done this. Nobody figured it out until Zoya came along."
Adds Popovic: "I think the challenge will be to get the first angel funding, because this is early technology still. I think we used to have a challenge to get research money to further develop the technology, but I actually have more funding than people to work on it."
Opportunities: Beyond the areas where there's an "obvious value proposition" like surgery and ICUs, Pollock says the big opportunity is licensing LumenAstra's technology to the Samsungs and Fitbits of the world.
Analysts estimate the annual U.S. market for home thermometry is about $1.2 billion -- spanning more than 100 brands -- and the medical market is much larger. Pollock says that a wide range of medical procedures, including cancer therapy, could benefit from more precise internal temperature readings.
Popovic says research indicates that circadian cycles get interrupted when the body's core and peripheral temperatures are out of phase.
"There are a huge number of psychological issues and eating disorders and sleeping disorders that are related to the circadian cycle," she explains. "If you can monitor [internal temperatures] over the long term, then when you know that this happens, you can apply external stimuli."
Needs: Capital, vendors, and employees -- namely "a couple of full-time engineers who are in the RF space and IoT," says Pollock. "Then we'll be looking for outsourcing for the design and manufacturing of the actual package, in that order."
LumenAstra and Popovic's lab have raised about $1.5 million to date, and the company is aiming to raise another $1 million in angel funding in 2022.