Real-time information about what's happening in our bodies at the cellular level could be crucial for fighting cancer and other life-threatening conditions. It would be incredibly helpful to know whether cancer drugs are reaching their targets or whether toxins are disrupting DNA in healthy cells. Now scientists at M.I.T. have created carbon nanosensors that they say can help answer those questions. The research was published December 14th in the journal Nature Nanotechnology. The researchers wrapped carbon nanotube sensors in DNA, and the coated sensors have been shown to be safe for living cells. The nanotubes emit infrared light. But that signal changes when cancer drugs or molecules that damage DNA bind with the sensor. By detecting the changes in signals, such as intensity and wavelength, the researchers have shown they can determine just what's happening to cells in real-time.