July 09, 2012, 8:40 PM — Scientists at Princeton University say they have used nanotechnology to make tests to detect diseases, like
cancer and Alzheimer's disease, 3 million times more sensitive.
That means what researchers are calling a breakthrough in nanotechnology and medicine could enable doctors to
detect these illnesses at much earlier stages, when they are more treatable.
"This advance opens many new and exciting opportunities ... in disease early detection and treatment," said Stephen Chou, a Princeton engineering
professor, who led the research team. "You can have very early detection with our approach."
Princeton researchers used nanotechnology
to improve a biological test called an immunoassay, which measures the concentration of a substance in a body fluid
sample, and is used to find markers for cancers and Alzheimer's, in patients. The test produces a fluorescent glow
when the disease is detected. The stronger the presence of the disease, the brighter the test glows.
However, if only faint, early-stage, traces of the disease are present, the glow can't be detected and the
disease could be missed.
The Princeton researchers used nanotechnology to amplify the fluorescence, which gave them a 3-million-fold
improvement in detection. It means the test now can detect disease with 3 million times fewer disease biomarkers
The earlier a cancer can be detected, the sooner treatment can begin, and the better chance a patient has of
The key to the breakthrough, according to Princeton's researchers, lies in a new nanomaterial they call D2PA.
The nanomaterial, which was developed in Chou's lab, consists of a thin layer of gold nanostructures surrounded by
glass pillars that are 60 nanometers in diameter. About 1,000 of the pillars can be laid side-by-side and still
only be as wide as a human hair.
Each pillar, spaced 200 nanometers apart, is capped with a gold disk. Each pillar also is speckled with even
smaller gold dots. The pillars boost the collection and transmission of light by a billion-fold, Princeton
The university noted that Chou is focused on using the new technology to detect early-stage breast and prostate
cancers. He also is working with researchers at the Memorial Sloan-Kettering Cancer Center in New York to develop
tests to detect proteins associated with early stage Alzheimer's disease.