Subscribe to our Nanotechnology Spotlight feedSwimming microrobots propelled by bacteria
It's not quite like in Isaac Asimov's science fiction classic Fantastic Voyage, where five people travel in a submarine inside a person's blood stream, but scientists have talked for quite some time about micro and nanorobotic devices that can travel inside the human body and carry out a host of complex medical procedures such as monitoring, drug delivery and cell repair. Recent developments in micro- and nanoscale engineering have led to realization of various miniature mobile robots. It turns out that the most significant bottleneck for further miniaturization of mobile robots down to micrometer scale is the miniaturization of the on-board actuators and power sources required for mobility. Nature has already provided remarkable solutions to this problem by evolving chemically powered molecular motors. Such biomotors seem to be one of the most promising choices for on-board actuation. They are advantageous over man-made actuators because they are much smaller in size and are capable of producing more complicated motions. More importantly, they convert chemical energy to mechanical energy very efficiently. However, the major drawback of biomotors is that isolating and reconstituting them are complicated tasks with low yield and it is difficult to interface them with electronic circuitry. This has led scientists to successfully experiment with a new approach by using flagellar motors (the propulsion system of bacteria), still inside the intact cells, as actuators.
