Researchers at Purdue University have taken a step toward developing a new type of ultra-sensitive medical imaging technique that works by shining a laser through the skin to detect tiny gold nanorods injected into the bloodstream. In tests with mice, the nanorods yielded images nearly 60 times brighter than conventional fluorescent dyes, including rhodamine, commonly used for a wide range of biological imaging to study the inner workings of cells and molecules.

Gold nanorods, which fluoresce red, were photographed inside the blood vessels of a live mouse.

The nanorods might be used to develop an advanced medical imaging tool for the early detection of cancer, said Ji-Xin Cheng, Ph.D., one of three Purdue faculty members who participated in this study. Dr. Cheng and his colleagues published their work in the journal Proceedings of the National Academy of Sciences.

( www.nano.cancer.gov)