Bacteria navigate microparticle swarms to target:
a biohybrid microrobot develops
Latest publication in Scientific Reports
June 25, 2015
In the 1966 movie Fantastic Voyage, a submarine complete with crew is shrunk in size so that it can navigate through the human body, enabling the crew to perform surgery in the brain. This scenario remains in the realm of science fiction, and transporting a surgical team to a disease site will certainly remain fiction. Nevertheless, tiny submarines that could navigate through the body could be of great benefit: they could deliver drugs precisely to a target location, without causing side effects and stressing the whole organism.
If things go according to Metin Sitti, director of the Physical Intelligence Department at the Max Planck Institute for Intelligent Systems in Stuttgart, with the help of biohybrid microrobots targeting therapy for example within stagnant fluids inside the human body such as inside the eye, spinal cord fluid, brain lobes, or urinary tract could in the foreseeable future come close to reality. The little helpers would accurately home-in on targets in the body, releasing a significant amount on drug precisely at the wished target location, without stressing the rest of the human body with side effects that this medication could potentially generate.
That this dream based on the Fantastic Voyage could come true in the near future is strengthened by recent scientific outcomes, published in Scientific Reports (Nature) this month. Researchers from the Carnegie Mellon University in Pittsburgh, USA and the Max Planck Institute for Intelligent Systems in Stuttgart have shown recently that flagellated bacteria attached to a large number of microparticles can carry the microsystem as a swarm to the desired target.
Maintaining an appropriate environment, like optimal pH level or non-polluted surrounding is essential for the survival of most microorganisms like bacteria, and they have developed sensing and propelling behaviors to move away from “un-wished or bad” environments. Flagellated bacteria such as E. coli or S. marcescens move self-propelled towards a desired pH level, which is called pH-taxis.
Scientist now take advantage out of these “natural” properties and link bacteria (bio-component) to artificial components like microparticles, to create swarms of biohybrid microrobots with a size of 1 to 5 micron (micron = 1/1000 mm), which can be manufactured fast at low costs.