Magic Beacons and Magic Bullets: The Medical Applications of Functional Nanoparticles
Nanotechnology is a multidisciplinary activity, breaking through the barriers between physics, chemistry, and biology. Since its emergence there have been attempts to exploit it in medicine and to explore whether it is possible to use it to overcome certain persistent problems in conventional medical treatments. An example is in cancer therapies that use highly toxic drugs, and the treatment is a balancing act between harming the patient and treating the cancer. There has been a steady improvement in the 5-year survival rate, which in the United States averaged over all cancers in the last 10 years has reached 66% . The basic abiding problem is that it is hard to concentrate the available drugs in the tumour tissue so that doses are limited by the toxicity of the drug. Improvements in diagnosis and early detection are also very important and in both therapy and diagnosis, nanoparticle-based techniques are being intensively researched.
Nanoparticles are already available for some applications—for example, as magnetic resonance imaging (MRI) contrast enhancers (see Section 6.3.1). This is only the beginning, however, and it is believed that nanotechnology will make a significant contribution to improvements in health care. Most envisaged future medical applications use nanoparticles that are programmed to individually perform a function, thus conforming to the definition of evolutionary ...