The 1966 movie Fantastic_Voyage depicted the miniaturization of organic and inorganic material.
https://en.wikipedia.org/wiki/Fantastic_Voyage#Plot
The ability to reduce material structure as portrayed in the movie, still seems to be a very long ways off.
However, nanotechnology is quite real.
https://en.wikipedia.org/wiki/There's_Plenty_of_Room_at_the_Bottom
https://en.wikipedia.org/wiki/Nanorobotics
https://thenextweb.com/news/youll-injecting-robots-your-bloodstream-fight-disease-soon
https://en.wikipedia.org/wiki/Nanomedicine
There could be some challenges and risks with AI nanotechnology.
https://en.wikipedia.org/wiki/Impact_of_nanotechnology#Health_hazards
https://en.wikipedia.org/wiki/Nanotechnology#Research_and_development
Just like almost anything, AI nanotechnology can be weaponized.
