This research has been published online in the journal of Scientific Reports.
Scientists have developed these bio-bots by combining heart muscle cells onto the body of hydrogel, which is also used to develop contact lenses for human eye, using 3D printer that laid down successive layers of soft materials that were joined together and hardened. These bio-bots are soft, biocompatible, and able to walk by themselves. Interestingly, they are just 7 mm in length.
“The idea is that, by being able to design with biological structures, we can harness the power of cells and nature to address challenges facing society,” Rashid Bashir, an Abel Bliss Professor of Engineering, said in a statement. “As engineers, we’ve always built things with hard materials, materials that are very predictable. Yet there are a lot of applications where nature solves a problem in such an elegant way. Can we replicate some of that if we can understand how to put things together with cells?”
Scientists have used the rhythmic activity of thousands of heart cells to move the bots forward. These rat heart cells cover the thin leg of the bot. The bio-bot has two legs, one propels it forward and the other acts as stabilizer.
At this time, biobots need nutrient-rich fluid to keep the heart cells alive but researchers believe that these could be “fed” via veins in the future.
“Work going on in other labs is aimed at creating vascular systems to meet the metabolic needs of muscles for biobots as they become more developed and grow in scale,” Roger Kamm, a mechanical engineer at MIT, who was not involved in the study, said in a statement.
According to the experts, these bio-bots are not only helpful in medical field but could equally be used in energy and environmental industry. The bio-bots could be made to respond to certain stimuli by integrating cells for those stimuli and in this way they could be used as sensors. They can also be used in drug screening and chemical analysis.
“I think we are just beginning to scratch the surface in this regard,” said graduate student Vincent Chan, first author of the paper. “That is what’s so exciting about this technology – to be able to exploit some of nature’s unique capabilities and utilize it for other beneficial purposes or functions.”
Vincent Chan, Kidong Park, Mitchell B. Collens, Hyunjoon Kong, Taher A. Saif & Rashid Bashir, (2012). Development of Miniaturized Walking Biological Machines. Scientific Reports, doi:10.1038/srep00857None found.