Space mission for nanosensors. (Technology).

Future space travelers can look forward to healthier trips into the cosmos. Scientists have begun research into nanomolecular devices to place inside an astronaut's white blood cells to detect early signs of damage from dangerous radiation or infection.

"Radiation-induced illness is

a serious concern in space travel," says James R. Baker Jr., professor of nanotechnology at the University of Michigan Medical School's Center for Biologic Nanotechnology. "Radiation changes the flow of calcium ions within white blood cells and eventually triggers irreversible cell death."

The goal for Baker and his team is a noninvasive system that, when placed inside the blood cells of astronauts, will monitor continuously for radiation exposure or infectious agents. The project, funded by NASA, builds on expertise and technology developed during a nanotechnology research study for the National Cancer Institute to produce intracellular devices that sense premalignant and cancerous changes inside living cells.

Created from synthetic polymers, the devices are fabricated into spheres with a diameter of less than five nanometers. Because the nanosensors are so small--one-billionth of a meter--Baker says they pass easily through membranes into lymphocytes (white blood cells), where they can detect the first signs of biochemical changes from radiation.

Nanosensors will avoid problems associated with current implanted sensors, which are much larger and can cause inflammation. They will also eliminate the need to draw and test blood samples. University of Michigan scientists hope the devices can be administered through the skin every few weeks, avoiding the need for injections or IVs during space missions.

Source: University of Michigan Health System, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109. Web site www.med.umich.edu.