Medical physicists at the University of Virginia have created a novel way to kill tumor cells using quantum dots and light.

Upon exposure to high doses of radiation, the dots become luminescent and emit light that triggers the cancer-killing activity of Photofrin. The only photosensitizer currently approved by the FDA, Photofrin is absorbed by cancer cells and upon exposure to light becomes active and kills cells.

In theory, the process, which so far has been studied only in cancer cells grown in culture, could work on tumors located too deep within the body to be reached by an external light source.