8 bit computers floating around inside living things?

Scientists have made DNA based robotsnanobots – to carry medicine to diseases and release drugs when the diseases are reached. By using DNA folding, drugs can be stored inside cages of DNA molecules. The DNA will unfold when it touches the right protein. They have made the DNA unfold when it touches certain disease molecules. These have been injected into cockroaches. These robots can behave like nanocomputers, and while we will soon be making them about as powerful as a Commodore 64 from the 1980s, how long until we have 64 bit computers traveling our bloodstreams, repairing damaged cells, transmitting information on our health at a cellular level?