Join the dots

Biologically compatible nano dots that glow under certain physiological conditions can show surgeons precisely where tumor cells are in the body. According to researchers at the Memorial Sloan-Kettering Cancer Center, the "Cornell dots", or C dots, consist of several dye molecules encased in a silica shell just a few nanometers in diameter and coated with polyethylene glycol (PEG). Cornell materials scientist Ulrich Wiesner and colleagues explain that these nanoparticles can be transported into tissues, are safe and readily excreted by the kidneys after imaging of tumors, their blood vessels, and metastatic tissues have been obtained. Physician-scientist Michelle Bradbury explains that the Cornell dots are highly sensitive and can ensure the earliest possible detection of tumor cells.