Sarles Speaks in Switzerland
Three years ago, Andy Sarles embarked on a $4 million grant from the United States Air Force Office of Scientific Research to push the frontiers of biotechnological integration.
“Our main goal is to understand how to design new types of sensing and computing technologies from material interfaces that can process information the same way the cells in our body do,” explained Sarles, a professor and the James Conklin Faculty Fellow in the Department of Mechanical and Aerospace Engineering.
Electronic devices like smartphones and computers send and receive signals coded as electrons, but human cells use chemicals—from single ions like potassium and sodium to larger hormones and neurotransmitters.
Sarles and his partners at Northwestern University and the University of California Los Angeles are creating biomimetic (biologically inspired) interfaces that will act as translators between the two worlds.
“Through the course of the project, multiple PhD students from Northwestern have come to my lab, bringing devices they built in clean rooms and learning new techniques to take back with them,” Sarles said. “It’s a very beneficial partnership and something we’re hoping to continue.”
Last October, Sarles was invited to deliver a Distinguished Lecturers Seminar on his progress with biomimetic engineering at the Institute of Electrical and Micro Engineering, part of the world-renowned research university École Polytechnique Fédérale de Lausanne (EPFL) in Lausanne, Switzerland.
“In addition to meeting with several well-known biomimetic materials scientists, I also had the pleasure to catch up with a former visiting student and meet her current postdoctoral advisor at EPFL,” Sarles said. “She spent three weeks in my lab learning techniques that helped her earn her PhD at Northwestern. It is rewarding to see that students from this project are staying involved and working at these amazing places.”
More Flexible Medical Tools
Currently, scientists interested in listening in on the body rely on stiff electrodes inserted into muscles or brain tissue. The inflexible instruments can cause pain in patients and have been known to damage or even scar the tissues under study.
They are also limited to reading electrical potentials, so chemical signals which make up most of the body’s information exchanges remain unobserved.
A few available devices on the market surround electronic components in a flexible, conductive polymer, enabling them to receive ion signals, but the ions bounce away from the devices so quickly that they are not always registered correctly.
So far, Sarles’ lab is the only one that has successfully added a third coating to such devices: a lipid bilayer, the biological material that encases cells. While the two-molecule-thick coating is extremely difficult to work with, the result is well worth the effort.
“Our method for forming lipid membranes as a coating gives a much better-quality membrane than you get with other techniques,” Sarles said. “Ions can be trapped in the biopolymer for a few seconds to minutes, which gives us more sensitivity to ionic signals.”
Retaining the ions also gives Sarles’ device the unique ability to “remember” the signals it has received, expanding its functionality tremendously and much more closely mimicking cell-to-cell signaling events.
While Sarles and his colleagues are very pleased with their progress, there is still a long way to go before their technology is ready to leave the lab. Once they can make membrane coating more reliable, the next challenge will be incorporating membrane proteins that enable signaling with larger materials, like hormones and neurotransmitters.
“Cracking this problem would improve health monitoring and enable us to learn a lot more about how biological tissues function,” Sarles said. “It could even enable personalized medicine, if you used it to tailor how a drug delivery system provides treatment or to improve communication between prosthetics and living tissues. That’s why we want to keep pushing this technology forward—there’s real value in it.”
Contact
Izzie Gall ([email protected])