Microelectronics give researchers a remote control for biological robots

First, they walk. Then they saw the light. Now, miniature bio-robots have gained a new trick: remote control.

The hybrid “eBiobots” are the first to combine soft materials, live mechanics, and microelectronics, say researchers at the University of Illinois Urbana-Champaign, Northwestern University, and collaborating institutions. They describe their centimeter scale biological machine in the magazine robotics science.

“The integration of microelectronics allows the fusion of the biological world and the electronic world, both of which have their own advantages, so that the production of these electronic machines and biobots can be useful,” the study said. for many future medical, sensor and environmental applications”. co-leader Rashid Bashir, Illinois professor of bioengineering and dean of Grainger College of Engineering.

Bashir’s team has pioneered the development of biobots, small biological robots powered by mouse muscle tissue grown on soft 3D printed polymer skeletons. They demonstrated the walking biobot in 2012 and the light-activated biobot in 2016. Light-activated gives researchers some control, but practical applications are limited. by the question of how to transmit light pulses to the biobot outside of a laboratory environment.

The answer to that question comes from Northwestern University professor John A. Rogers, a pioneer in the field of flexible bioelectronics, whose team helped integrate microscopic wireless microelectronics and lamps Ultra-small LED does not use batteries. This allows researchers to control eBiobots remotely.

“This unusual combination of technology and biology opens up many opportunities in the creation of engineering systems that are self-healing, learning, growing, communicating, and self-organizing. We feel that that’s the case. is very fertile ground for future research with specific potential applications in biomedicine and environment control“, said Rogers, professor of materials science and engineering. Biomedical engineering and Neurosurgery at Northwestern University and director of the Querrey Simpson Institute for Bioelectricity.

To give the biobot the freedom of movement needed for practical applications, the researchers set out to get rid of bulky batteries and tethers. First co-author Zhengwei Li, assistant professor of biomedical engineering at the University of Houston, says the eBiobots use a collector coil to capture energy and provide a regulated output voltage to power the lights. Ultra-small LED.

The researchers can send wireless signals to the eBiobots to trigger the LEDs. The light-sensitive designed muscle stimulator LEDs contract, moving the polymer pins for the machine to “go”. The micro LEDs are targeted so that they can activate specific muscle parts, causing the eBiobot to rotate in the desired direction.

The researchers used computational modeling to optimize the eBiobot design and integrate components for durability, speed, and maneuverability. Illinois professor of mechanical science and engineering Mattia Gazzola led the simulation and design of the eBiobots. Gazzola and first co-author Xiaotian Zhang, a postdoctoral researcher in Gazzola’s lab, say the iterative design and additive 3D printing of the scaffolds allow for rapid experimental cycles. quickly and improve performance.

Co-first author Youngdeok Kim, who completed the work as a researcher: PhD student in Illinois.

Integrating electronic sensors or biological neurons will allow eBiobots to sense and respond to environmental toxins, biomarkers for disease, and more capabilities, the researchers say. other ability.

“In developing the first hybrid bioelectronic robot, we are opening the door to a new model of application for healthcare innovation, such as biopsies and in situ analysis, invasive surgery, etc. minimally invasive or even cancer detection in the human body,” Li said.