The new microbot inspired by starfish larva stirs up plastic beads. Among scientists, there is great interest in tiny machines that are set to revolutionise medicine. These microrobots, often only a fraction of the diameter of a hair, are made to swim through the body to deliver medication to specific areas and perform the smallest surgical procedures. The designs of these robots are often inspired by natural microorganisms such as bacteria or algae. Now, for the first time, a research group at ETH Zurich has developed a microrobot design inspired by starfish larva, which use ciliary bands on their surface to swim and feed.
MIT engineers have designed tiny robots that can help drug-delivery nanoparticles push their way out of the bloodstream and into a tumor or another disease site. Like crafts in "Fantastic Voyage" -- a 1960s science fiction film in which a submarine crew shrinks in size and roams a body to repair damaged cells -- the robots swim through the bloodstream, creating a current that drags nanoparticles along with them. The magnetic microrobots, inspired by bacterial propulsion, could help to overcome one of the biggest obstacles to delivering drugs with nanoparticles: getting the particles to exit blood vessels and accumulate in the right place. "When you put nanomaterials in the bloodstream and target them to diseased tissue, the biggest barrier to that kind of payload getting into the tissue is the lining of the blood vessel," says Sangeeta Bhatia, the John and Dorothy Wilson Professor of Health Sciences and Technology and Electrical Engineering and Computer Science, a member of MIT's Koch Institute for Integrative Cancer Research and its Institute for Medical Engineering and Science, and the senior author of the study. "Our idea was to see if you can use magnetism to create fluid forces that push nanoparticles into the tissue," adds Simone Schuerle, a former MIT postdoc and lead author of the paper, which appears in the April 26 issue of Science Advances.
MIT CSAIL's origami robot is packaged in an ingestible ice pill. In 2013, University of Sheffield roboticist Dana Damian was doing postdoctoral research at Harvard Medical School affiliate Boston Children's Hospital when she learned of a procedure called the Foker technique. The surgery, performed on children with a rare congenital lung defect, calls for doctors to attach sutures to part of an infant's esophagus, then tie them off on the baby's back. Over time, the sutures lengthen the esophagus by pulling on it, stimulating tissue growth. Although the technique can be effective, the risk of infection and complication is high, and the baby must remain under sedation for weeks.
In 1959, Nobel laureate and nanotechnology visionary Richard Feynman suggested that it would be interesting to "swallow the surgeon" -- that is, to make a tiny robot that could travel through blood vessels to carry out surgery where needed. This iconic imagining of the future underscored modern hopes for the field of micrometre-scale robotics: to deploy autonomous devices in environments that their macroscopic counterparts cannot reach. However, the construction of such robots presents several challenges, including the obvious difficulty of how to assemble a microscopic locomotive device. In a paper in Nature, Miskin et al.1 report electrochemically driven devices that propel laser-controlled microrobots through a liquid, and which could be easily integrated with microelectronics components to construct fully autonomous microrobots. Designing propulsion strategies for microrobots that move through liquid environments is challenging because strong drag forces prevent microscale objects from maintaining momentum2.