(at the end of the article) Perhaps the most extraordinary example of a talking medicine uses not microtechnology but a branch of nanotechnology - dendrimer chemistry - to create single molecules, each of which is both a drug and communication device. Researchers at the University of Michigan have used this to devise an “intelligent” cancer treatment: after injection into the bloodstream, the drug locates the cancer cells. On finding its target, the drug molecule reports its location and enters the cell. It then confirms that it is inside a cancer cell, and reports when it has destroyed it. This would also give the specialist useful information about the location of the tumour.