Fantastic Voyage - Nanotechnology

Scientists are crafting microscopic vessels that can venture into the human body and repair problems – one cell at a time.

It's like a scene from the movie Fantastic Voyage. A tiny vessel - far smaller than a human cell - tumbles through a patient's bloodstream, hunting down diseased cells and penetrating their membranes to deliver precise doses of medicines.

Only this isn't Hollywood. This is real science.

Researchers funded by a grant from NASA recently began a project to make this futuristic scenario a reality. If successful, the "vessels" developed by these scientists - called nanoparticles or nanocapsules - could help make another science fiction story come true: human exploration of Mars and other long-term habitation of space.

While space applications will be the researchers' primary focus, nanoparticles also hold great potential for many fields of medicine, particularly cancer treatment. The tantalizing promise of delivering tumor-killing poisons directly to cancerous cells, thus averting the ravaging side-effects of chemotherapy, has generated a lot of interest in nanoparticles among the medical community.

"The purpose of these nanoparticles is to introduce a new type of therapy - to actually go inside individual cells ... and repair them, or, if there's a lot of damage, to get rid of those cells," explains James Leary of the University of Texas Medical Branch. Leary is leading the research along with Stephen Lloyd, and Massoud Motamedi, also from the University of Texas; Nicholas Kotov of Oklahoma State University; and Yuri Lvov of Louisiana Tech University.

Copyright 1999, Daniel Higgins, University of Illinois at Chicago. Tiny capsules much smaller than these blood cells may someday be injected into people's bloodstreams to treat conditions ranging from cancer to radiation damage.

Their project will focus on a problem related to cancer - the high radiation doses experienced by astronauts in space, especially on journeys to the Moon or to Mars, which require leaving the protective umbrella of the giant magnetic field surrounding the Earth.

Image courtesy NASA/OBPR. High-energy cosmic radiation can cause damage DNA and make cells behave erratically.

Even the advanced materials used for radiation shielding on spacecraft can't fully insulate astronauts from the high-energy radiation of space. These photons and particles pierce the astronauts' bodies like infinitesimal bullets, blasting apart molecules in their path. When DNA is damaged by this radiation, cells can behave erratically, sometimes leading to cancers.