There are graphene sheets that have been doped with other molecules in much the same way semiconductors are made. One of these has been named "graphene oxide" because the doping molecules are oxygen. These substances do react to magnetic or electrostatic fields. It is probably possible to make organized semiconductors with graphene.
All that aside, I seriously doubt that these things can be made to reorganize themselves or find their way to the surface to flake off in sheets that are more massive than anything that could be injected using those fine gauge needles.
Graphene can be weird; but, our science is nowhere advanced enough to make nano-bots that would execute some sinister program.
Look up "graphene oxide". It isn't merely CO2.
Honestly I haven't looked into graphene oxide In vitro. Though I know it spreads out under the skin and will act as an antenna and a very low millivolt battery. It could easily be used to generate a random number.
This is my take on it without looking anything up. I'm sure there is likely more to it then this.
The reason we take Vitamin C is for an antioxidant. The antenna would create oxidants. With the low millivolt battery your cells could never rest.
Cell rest is critical for mitochondrial health. I've noticed these injections primary attack from many different ways is against our mitochondria.
Graphene oxide will brake down in the body with sulfurs from your foods. Some of it will never brake down in muscle tissue.