The Possibilities are Mote and Remote

Azita Emami’s work in high-speed data communications led to a breakthrough that could spare millions of people the need to prick themselves with needles.

Don’t see the connection? Emami explains how technologies for high-performance computers and communication systems inspired a medical innovation that may help people with diabetes monitor their glucose levels: “Solutions in both domains are very, very small. And they are wireless.”

Emami was appointed Caltech’s Andrew and Peggy Cherng Professor of Electrical Engineering and Medical Engineering in 2017, when the co-founders of Panda Express endowed the Andrew and Peggy Cherng Department of Medical Engineering at Caltech. She adds this to her title of executive officer of Caltech’s Department of Electrical Engineering and Heritage Medical Research Institute Investigator, which she acquired in 2015 through a gift from Caltech trustee Richard Merkin, CEO and founder of Heritage Provider Network, Inc.

To describe her work, both mote and remote, she says: “We design low-power, energy-efficient ways for the information world to interface with the physical world.”

 

Less is More

Civilization is heading deep into cloud computing and relying more and more on machine-learning algorithms for challenges ranging from combatting fraud to improving search query results. As the power of computers and servers continues to grow, Emami and a cadre of electrical engineers are figuring out how to accommodate the ever-increasing flow of information.

Low power is key. A processor running on less power dissipates less heat, and a cooler processor is a faster processor. Emami is devising ways to achieve the utra-low power consumption that is essential for data communication at a rate of tens of gigabytes per second.

As she engineers a more connected world, she also is working to make it a healthier one. Emami doesn’t draw a line between the two endeavors. “Electronic systems for cell phones and computers are very, very advanced,” she explains. “So why not take the knowledge we have gained developing those technologies and find ways to apply it toward solutions in medicine?”

One example of such a crossover solution is a microdevice that may help thousands of people who have suffered vision loss due to retinal disease. Emami designed a chip containing hundreds of cell-stimulating electrodes for a device that can stand in for damaged photoreceptors. Once implanted in the eye, it transmits signals to the retinal nerves. Thanks to the brain’s remarkable ability to adapt, after patient training these signals can be processed as visual information. Reducing power consumption for this device was essential because heat could cause tissue damage.

How Low Can You Go?

Getting back to the glucose sensor: Emami and colleague Axel Scherer, Caltech’s Bernard Neches Professor of Electrical Engineering, Applied Physics and Physics, have designed an implantable device that can relay real-time glucose readings to a wearable reader.

Powered via wireless radio frequency, the external reader uses bluetooth capabilities to interface with the wearer’s cell phone. It can also send readings to other mobile devices, alerting care providers and physicians if a patient’s blood sugar dips or spikes dangerously out of normal range.

One challenge Emami and Scherer encountered in developing the device was finding a way for the sensor to convert its readings into electrical or optical signals using very little power. This was an essential step for the end user, because it is the process that yields data that can be interpreted and displayed.

 

“Creativity guides us to draw connections, to apply solutions to new problems to see if we can make them fit.”
- Azita Emami

“An undergraduate in one of my project courses proposed a digital clocking technique for high-speed optical interconnection systems,” Emami recounts. “After the class, he did a SURF [Summer Undergraduate Research Fellowship] with me and ended up using a very similar solution as a low-power way to convert glucose sensor readings from analog to digital, and co-authoring a paper about this new application.”

A Little Magnetism

Human trials for the glucose sensor are on the horizon, and FDA approval may follow in a few short years. Meanwhile, Emami aims to design a device that can not only measure health information such as blood sugar, cortisol, and pH levels, but also release insulin or other drugs as needed.

To this end, Emami has embarked on a research project in collaboration with assistant professor of chemical engineering and fellow Heritage Medical Research Investigator Mikhail Shapiro. The two developed a prototype microscale device they call ATOMS (short for addressable transmitters operated as magnetic spins). With this innovation, physicians will, for the first time, be able to pinpoint the precise location of a microdevice inside the body.

Together with Manuel Monge (MS ’10, PhD ’17), who was a doctoral student in Emami’s lab, and Audrey Lee-Gosselin, a research technician in Shapiro’s lab, Emami and Shapiro have designed a silicon chip that borrows principles of magnetic resonance imaging (MRI)—but without requiring a large machine to produce a strong magnetic field. Using a set of integrated antennas, sensors, and wireless transmission technology, the chip resonates at different frequencies as it moves through the body.

And just how tiny are these chips? Two ATOMS devices can sit side by side on a sesame seed—with room to spare.

Connecting the Dots

“Creative people are good at making connections,” Emami explains. “Creativity guides us to draw connections, to apply solutions to new problems to see if we can make them fit.”

She elaborates: “We had some general applications in mind for ATOMS. Then we published the paper, and physicians and other medical professionals began contacting us. We don’t know exactly what goes on in the operating room, so they are connecting the dots to show us how this new technology could improve surgeries and medical diagnostics. The clinicians are showing us that these tiny devices have huge potential.”

While hospitals and other industries connect their dots, Caltech’s engineers have the creativity and research support to go back to the drawing board and make more connections. In Emami’s mind, creativity—of faculty members, students, and postdocs alike—is a key ingredient to her department’s success. And collaboration and philanthropic support are powerful tools for stimulating creativity.

Donors to Break Through: The Caltech Campaign have bolstered flexible endowment that is enabling faculty and students across all six of Caltech’s academic divisions to pursue their most innovative ideas. In the Department of Electrical Engineering alone, Emami points to an infusion of unrestricted research funds, postdoctoral and doctoral fellowships, and scholarships provided by Caltech trustees Richard Merkin, Peggy Cherng (together with her husband, Andrew Cherng), and former Compaq chairman Benjamin Rosen (the latter having made a bequest commitment with his wife, Donna Rosen, to grow the endowment for Caltech’s Donna and Benjamin M. Rosen Bioengineering Center).

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