Gold standard imaging

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.

Findings are detailed in a research paper that appeared online last week in Proceedings of the National Academy of Sciences. The paper was written by researchers in Purdue's Weldon School of Biomedical Engineering and the Department of Chemistry.

The nanorods might be used to develop an advanced medical imaging tool for the early detection of cancer, said Ji-Xin Cheng, an assistant professor of biomedical engineering.

The gold rods are about 20 nanometres wide and 60 nanometres long, or roughly 200 times smaller than a red blood cell.