(CNN) -- Gray goo or the future of medicine? CNN spoke to Naomi Halas, a professor at Rice University in Texas, about nanotechnology and her work on nanoshells, tiny particles that may hold the key to curing cancer.
CNN: What exactly is nanotechnology?
Naomi Halas works in nanophotonics, the interaction of nanostructures and light
Naomi Halas: Nanotechnology is the science and engineering of everything at the nanometer scale. It's a bunch of different fields all united by working at the same length scale.
CNN: Tell us about the field you work in.
NH: My major interest is the interaction of nanostructures and light. It's a field within nanotechnology called nanophotonics and it's a very special, rapidly growing field because it has within it many practical applications for nanotechnology that range across a whole variety of different disciplines, from things like biomedical diagnostics to faster computer architectures.
CNN: What does your work focus on?
NH: We invented a nanoparticle called nanoshells. They have really quite unusual and special optical properties. If you were to look at them, they look like malted milk balls. They have glass cores and a thin metal shell -- the crunchy part of a malted milk ball is glass and the chocolate part is the metal shell. That's a very important geometry, because if we can control the relative size of the inner and outer layer of the shell we can tune what wavelength of light that particle absorbs.
When light hits a nanoparticle then the nanoparticle converts the light to heat and literally focuses light around itself and heats the local surroundings. We can use that effect for photothermal heating in tumors to induce cell death. (Read more on how Professor Halas's nanoshells work.)
CNN: What stage is your work at?
NH: The work that we've done on photothermal cancer therapy has been extensively studied in animals -- rats, rabbits, mice -- and has now extended into large animals. We're anticipating that human trials will be undertaken at some point this calendar year, sometime in 2007.
CNN: Does the medical world embrace this new way of treating cancer?
NH: I've been quite surprised by how positively people have responded. People need to remember that people come into medicine because they want to alleviate human suffering. In general, when exposed to a new technology you have people who get very excited about it because they realize this is something that will actually help them achieve their goal. If we can make cancer a simple and manageable disease, as opposed to a disease that causes so much loss and grief in society, that's very exciting for people.
CNN: Do you think the patients -- the public -- are ready for nanoscale technology?
NH: There have been some unfair misrepresentations of nanoscale technology. Science fiction is delightful entertainment, but now nanotechnology really is a field and successes are being achieved in the laboratory, and one can really see what it does do.
Unfortunately, nanotechnology has gotten off to a start that has caused controversy - it's been labeled in many ways as a controversial or fearful new technology, and I believe very strongly that's a misrepresentation.
Of course we should be careful about our environment, but we're already dealing with conventional chemicals and conventional issues that relate to environmental contamination that will very likely far outweigh problems introduced by nanotechnology.
CNN: What sort of environmental impact do your nanoshells have?
NH: I know that our own nanoparticles are benign: they are essentially biocompatible, because they are made with gold. Gold is a highly biocompatible substance. They are non-toxic particles -- you could eat them, you could drink them, you could put them in your bloodstream and there's no harm whatsoever.
When these particles are eventually approved for cancer therapy, they would, in fact, be the first non-toxic cancer therapy. Currently, all cancer therapies are toxins. They're poisons. For example, if you have a chemotherapy drug, as it passes through the bloodstream it destroys blood cells, sometimes to a great degree, en route to the tumor. It will eventually destroy the tumor as well, but chemotherapy drugs are so potent because they are toxins.
This would be, by contrast, a completely different type of therapy because it's non-toxic. It would pass through the bloodstream essentially unrecognized by your immune system. Then, arriving at the tumor site, it would be completely inactive until the specific wavelength of light is shone onto the particles. They absorb light, do their photothermal task and destroy those local cells, and they would eventually leave the body through the liver.
CNN: So there are no side effects?
NH: One would anticipate that the side effects for a non-toxic therapeutic like this would be minimal. Of course, doctors don't determine the choice of treatment based on side effects: they determine a treatment based on whether a patient will survive -- what's the likelihood that health will resolve and that we can sustain this person and remove the cancer.
CNN: What sort of success rate are you seeing with nanoshells?
NH: In this case, we have tremendously high remission rates for treatment in animals -- above 90%. The only times when there have been tumors that have not been destroyed have been when the tumor was not recognized in the first place and so it was not irradiated.
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