Military Nanotube Technology Developed To Save Radiation Victims

government has commissioned a nine-month study to determine whether a new drug based on carbon nanotubes can help prevent people from dying of acute radiation injury following radiation exposure. The new study was commissioned after preliminary tests found the drug was greater than 5,000 times more effective at reducing the effects of acute radiation injury than the most effective drugs currently available.

"More than half of those who suffer acute radiation injury die within 30 days, not from the initial radioactive particles themselves but from the devastation they cause in the immune system, the gastrointestinal tract, and other parts of the body,” said Dr. James Tour, professor of chemistry, director of Rice University (Houston, TX, USA) Carbon Nanotechnology Laboratory (CNL) and lead investigator on the grant. "Ideally, we'd like to develop a drug that can be administered within 12 hours of exposure and prevent deaths from what are currently fatal exposure doses of ionizing radiation.”

The U.S. Defense Advanced Research Projects Agency (DARPA; Arlington, VA, USA) has awarded Dr. Tour and co-principal investigators Drs. J. Conyers and Valerie Moore from the University of Texas Health Science Center at Houston (UT-Houston; USA) and Drs. Luka Milas, Kathy Mason, and Jeffrey Myers from the University of Texas M.D. Anderson Cancer Center (Houston, TX, USA) a US$540,000 grant for a nine-month study of an experimental drug that the investigators have named Nanovector Trojan Horses (NTH).

NTH is made at Rice's chemistry department and Carbon Nanotechnology Laboratory in the Richard E. Smalley Institute for Nanoscale Science and Technology. The drug is based on single-walled carbon nanotubes, hollow cylinders of pure carbon that are about as wide as a strand of DNA. To form NTH, Rice scientists coated nanotubes with two common food preservatives--the antioxidant compounds butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT)--and derivatives of those compounds.

"The same properties that make BHA and BHT good food preservatives, namely their ability to scavenge free radicals, also make them good candidates for mitigating the biological affects that are induced through the initial ionizing radiation event,” Dr. Tour said.

In preliminary tests at M.D. Anderson in July 2007, mice showed enhanced protection when exposed to lethal doses of ionizing radiation when they were given first-generation NTH drugs before exposure. "Our preliminary results are remarkable, and that's why DARPA awarded us this grant with a very compressed timeline for delivery: nine months, which is almost unheard of for an academic study of this type,” Dr. Tour said. "They are very interested in finding out whether this will work in a post-exposure delivery, and they don't want to waste any time.”

Ionizing radiation is any form of radioactive particle or energy that converts an atom or molecule into an ion by changing the balance between the number of protons and electrons. In living organisms, ionization often results in the creation of free radicals--highly reactive molecules that can wreak havoc by disrupting healthy physiologic processes. These free radicals induce a cascade of deleterious biologic events that cause further destruction to the organism in the days and weeks after initial radiation exposure event. NTH is designed to block the destructive biologic cascade.

According to Dr. Tour, the researchers are also interested in finding out whether the new drugs can prevent the unwanted side effects that cancer patients suffer after undergoing radiation therapy.


Related Links:
Defense Advanced Research Projects Agency
University of Texas Health Science Center at Houston
University of Texas M.D. Anderson Cancer Center