Researchers at the University of Illinois at Urbana-Champaign have developed centimeter-scale biobots that combine soft materials, mouse muscle tissue, and wireless electronic components. The tiny devices can be controlled remotely through optogenetics. The muscle within the devices forms an optogenetic actuator and creates movement when exposed to light. The researchers can control this movement remotely by activating on-board micro-LEDs wirelessly, which then stimulate the muscle actuators to propel the biobot. The technology could be used in the future to perform tasks within the body, such as surgical applications or drug delivery.
Optogenetics, a technique in which light stimulation can produce specific effects in genetically modified cells, could be very useful for biomedical applications, including both clinical and research activities. However, the technique requires light to reach the modified cells or tissues before the desired effect can be produced, which can be a problem inside our bodies. Possible solutions include fiber optic cables that are advanced into the body from the outside, but this is cumbersome and prone to infections.
These researchers have taken optogenetics to the next level by using it as the basis for movement in a centimeter-scale biobot. The tiny devices incorporate soft materials with mouse muscle tissue that is light sensitive and can produce movement when stimulated with the correct type of light. However, employing the biobot inside the body required a new approach that would allow the device to illuminate itself in response to a wireless command, and thereby produce movement.
The solution included integrating microelectronic components into the device that would allow it to illuminate several on-board micro-LEDs. These components include a receiver coil that allows the biobots to harvest their own power, meaning that they are battery-free. Each micro-LED illuminates a different portion of the muscle tissue within the biobot, allowing for accurate movements such as turning in a specific direction.
“Integrating microelectronics allows the merger of the biological world and the electronics world, both with many advantages of their own, to now produce these electronic biobots and machines that could be useful for many medical, sensing and environmental applications in the future,” said Rashid Bashir, a researcher involved in the study
See a video about the technology below:
Study in journal Science Robotics: Remote control of muscle-driven miniature robots with battery-free wireless optoelectronics