We have heard more about direct drug delivery using nanosystems, particularly for cancer treatment. Cancer drugs are highly toxic and the trick is to deliver the drugs at doses that are high enough to kill the cancer without killing the patient. But nanotechnology gives the answer. A simple and inexpensive way is to make nanoparticles of about 80 to 100 nanometres in diameter as developed by Professor Max Lu. These tiny mineral-like particles, made out of harmless substances used in antacid tablets, have a double-layered chemical structure that can surround and bind a drug, a piece of DNA or another snippet of genetic material which has the power to switch off genes or stop viruses replicating. Once the nanoparticle is inside a cell, it dissolves, releasing its medical package. Our bodies are primed to detect and mount an attack against tiny viruses. Nanotechnologists have exploited this to make new vaccines that resemble viruses, so they trigger a powerful immune response. Professor Ian Frazer's cervical cancer vaccine, Gardasil, is an example.