Bio-bots are cell-based soft robotic self-actuated living machines (biologically powered mechanical devices). This is the most advanced and very recent form of cellular living machines. Generally, bio-bot composed of “biological bimorph” or actuator (cells as a power source) and backbone biomaterial. Currently, bio-bots are only ex vivo engineered phenomenon – an experimental “sandbox”. Ultimately, bio-bots could be used in medicine for controlled drug delivery or as biosensors in vivo and for drug screening and toxicology ex vivo. A pioneer of bio-bots development from University of Illinois at Urbana-Champaign – Rashid Bashir says:
“The idea of doing forward engineering with these cell-based structures is very exciting,” Bashir said. “Our goal is for these devices to be used as autonomous sensors. We want it to sense a specific chemical and move towards it, then release agents to neutralize the toxin, for example. Being in control of the actuation is a big step forward toward that goal.”
I’d indicate a few generations of bio-bots in development:
- Simple uncontrolled bots – able to self-actuate, locomotion (usually powered by cardiomyocytes).
- Partially controlled – activated by external signals (usually powered by skeletal muscle cells).
- Fully controlled – could be controlled remotely after implantation (ex: optogenetically modified cells activated by light)
- Sensing bots – contains different types of neurons, able to sense chemical signal and act toward it.
- Fully controlled sensing multifunctional bots – composed of multiple cell types, able to: sense, move, deliver therapeutic, neutralize toxic substance, self-destroy…
Currently, second generation of bio-bots was created and third generation in development. Now, I’m going to give a few examples of bio-bots.
First self-assembled bot
In 2005, Carlo Montemagno’s group, described the first prototype of bio-bot, powered by self-assembled cardiomyocytes.
Crab-like bot. One of the earliest cardiomyocyte-powered crab-shaped microbot, created by Korean researchers, was able to walk in culture over a week and traveled about 50 meters.
First printed bot. Rashid Bashir group impemented 3D bioprinting to create walking bio-bot. Autonomous locomotion was powered by rat cardiomyocytes. This study was highly publicized and attracted a lot of attention.
2nd generation biobot. Bashir’s group created partially controlled electrically activated bot, powered by skeletal myocytes:
… this is the first demonstration of an untethered biological machine powered by engineered mammalian skeletal muscle and controlled purely via external signaling, and hence represents an important advance in building biointegrated soft robotic devices…
Researchers from CalTech and Hearvard U created swimming bioengineered jellyfish. Actuator was rat cardiomyocytes.
Researchers from German Institute for Integrative Nanosciences, created so-called spermbot – a biobot, which based on sperm cells. Because of magnetic microtubes, the device could be controlled remotely by a magnet. Read more about spermbots in this mini-review.
Self-propelled biohybrid. Taher Saif described synthetic flagellar swimmer, powered by cardiomyocytes.
Bacteria-powered swimmers. Researchers from Carnegie Mellon University described “bio-hybrid microswimmers propelled by multiple bacterial cells”.
What do you think about bio-bots? Is it our future or useless exercise? Any stratups yet?