A new imaging tool that can take pictures of cells and molecules deep inside the body is the first to use light rather than radiation to gather molecular signals. The new imaging process is referred to as Raman spectroscopy.

Researchers at Stanford University Medical School injected mice with nanoparticles directed to find cancer cells. The nanoparticles reflected light back out of the body and the cells were detected.

This scattering of light, called a spectral fingerprint, is unique to each type of molecule and can be measured. The researchers say the signals are stronger and longer-lived than other imaging methods. They also claim the process can transmit information about multiple targets at the same time such as a target on a cancer cell, a protein that is secreted by a cancer cell, or a protein inside the cancer cell.

The scientists believe that if their research can achieve positive results in human studies, Raman spectroscopy could help with early detection of cancer and become a routine medical procedure within three years.