The U.S. Food and Drug Administration (FDA) has approved the first clinical trial in humans of a new technology: Cornell Dots, brightly glowing nanoparticles that can light up cancer cells in PET-optical imaging.
A paper describing this new medical technology is published online in the Journal of Clinical Investigation (July 2011). This is a collaboration between Memorial Sloan-Kettering Cancer Center (MSKCC), Cornell University, and Hybrid Silica Technologies, a Cornell business start-up.
For the first time, scientists report a uniquely advanced and comprehensive characterization of Cornell Dots — an ultra small, cancer-targeted, multimodal silica nanoparticle — which has recently been approved as an “investigational new drug” (IND) by the FDA for a first-in-human clinical trial, says Michelle S. Bradbury, M.D., of the Memorial Sloan-Kettering Cancer Center and an assistant professor of radiology at Weill Cornell Medical College.
Cornell Dots are silica spheres less than 8 nanometers in diameter that enclose several dye molecules. (A nanometer is one-billionth of a meter, about the length of three atoms in a row.) The silica shell, essentially glass, is chemically inert and small enough to pass through the body and out in the urine. For clinical applications, the dots are coated with polyethylene glycol (PEG) so the body will not recognize them as foreign substances.
A guiding light within the body: To make the dots stick to tumor cells, organic molecules that bind to tumor surfaces or even specific locations within tumors can be attached to the PEG shell. When exposed to near-infrared light, the dots fluoresce much brighter than dye to serve as a beacon to identify the target cells. The technology, the researchers say, enables visualization during surgical treatment, showing invasive or metastatic spread to lymph nodes and distant organs, and can show the extent of treatment response.
