Nanobots - The Reality

So you see on the Internet little robot things that swim around your blood and kill germs……where can I get some?

The little robot things are sometimes called nanobots and they seem like a cool idea. If you need to kill some germs you just get some of these nanobots and they swim around and kill all of the bad germs. Nice idea, but they really do not exist. They are science fiction but they do sound cool. There are a lot of problems in making things really small and small enough to zoom through narrow places like in your blood stream. There are parts of your blood stream where the capillaries are only a thousand nanometers wide. That is really small.

Part of the problems is just controlling where the nanobots go because they are so tiny. Think about dust. It floats around and is blown by the wind. You can really control where it goes. You can catch it by using something like Endust®  but then it just sticks there. That is because things like static electricity are so powerful because the dust is so small that the dust defies gravity.

The other big problem is something called thermal motion. When things get really small, lets say 1/1,000th the width of a hair they vibrate almost uncontrollably. Probably you have seen this kind of vibration when you look at tiny stuff in water under the microscope. It is called Brownian motion. All of this rattling around makes it hard to keep little machines in one piece and so these nanobots would probably shake apart.

But the biggest problem is power. You want your nanobot to move. When something is 1/1000th the width of a hair or about 100 nanometers, it is really tough to move, especially in liquids. So to move along and chase germs you need a lot of power. To swim along a nanobot would probably need a battery that was about 1000 times bigger than itself and even that is just a guess. Tiny things like germs can swim but nobody is really sure how they do it but they power themselves using biological energy. That might be one way to power a nanobot but it is going to be really tough!

Can we someday figure all this out and make a nanobot? Sure. But we need to solve a lot of these problems and then you might ask why would we want to do it?