Typically science fiction authors and some sensational media portray nanorrobots as Asimov-style spaceship-like metal structures in "Fantastic Voyage".
But soon after we think about it, we realize that it is totally impossible, not only because it would be unthinkable to manufacture these types of machines with a size of 100 nanometers (billionths of a meter), but they must also be biocompatible and biodegradable.
If these machines are not compatible with our body, the same immune system would kill them as if they were a virus or any other pathogen.
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In reality these nanorrobots are devices made up of molecules that can move in a biological medium, converting chemical energy into kinetic energy or movement.
If we consider that a viscous biological fluid such as blood, for a device of that size is equivalent to navigating a submarine in a sea of jam, imagine the relative power that these nanomotors must have.
The latest development of a team of scientists from the University of Eindhoven, consists of a hybrid engine formed by a hollow organic capsule that houses the fuel that these scientists have synthesized inside and works as a propellant.
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The propellant with which these hollow structures are charged is formed from manganese dioxide, which, in the presence of hydrogen peroxide, reacts by releasing micro-bubbles of oxygen that cause the structure to move.
One of the most immediate applications of these devices is to selectively deliver drugs, driving these nanorobots into the affected tissue and releasing their drug load onto it.
And letting the imagination run wild, they could boost the immune system, detect and destroy cancer when they are just a handful of seditious cells, who knows.
