One of the most common and successful treatments for cancer is to apply chemotherapy, but this treatment has the problem that it also affects the healthy cells that surround the diseased cancer cells and many others.
For a long time, work has been done on the possibility of applying drugs "in situ" on cancer cells, and one of the most promising possibilities is through micro-robots that can circulate through the bloodstream and reach the place where the drug needs to be applied.
News of this type appears continuously and the one I am commenting on today is one more, but it has the peculiarity that the micro-robots that I comment on here behave differently depending on the acidity of the environment in which they are found.
In particular, a fish-shaped micro-robot has a mouth that opens or closes depending on the acidity of the environment, and it is useful to carry a medicine and deposit it (opening the mouth) when reaching an environment with a lower pH than it's where the cancer cells are.
After being manufactured, micro-robots are introduced into a suspension of iron oxide nano-particles so that they acquire magnetic properties and can then be oriented within the human body.
To guide the micro-robot through the body and reach its destination, they apply magnetic fields that move the robot towards the cancer cells. Once it has reached its destination, it opens its mouth and deposits the medicine in the vicinity of the cells to be eliminated.
A video can be seen at: https://youtu.be/-QxioOUyFLg
It is a "clean" and not very aggressive procedure that can give very good results and improve the effectiveness in the treatment of cancer and other diseases.
We will see in the near future great applications with micro-robots in many different fields.
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