Plasmonic Lasers Find, Destroy Circulating Tumor Cells to Prevent Metastasis

Though reasonably good techniques for ridding the body of primary tumors have been developed over the decades, preventing metastasis is still a major challenge. Circulating tumor cells (CTCs) break off from established tumors and wonder off to start new mets in other parts of the body. To prevent CTCs from safely traveling through the blood stream, researchers from Georgia State University, University of Arkansas for Medical Sciences, University of Arkansas at Little Rock, and Siberian Branch of the Russian Academy of Science have combined their expertise in different fields to use nano-scale devices called spasers to kill CTCs.

Spaser is an acronym for “surface plasmon amplification by stimulated emission of radiation”, also known as a plasmonic laser. Only about 20 nanometers in diameter, a spaser is able to absorb light, causing it to heat up. The heat can be so great that nearby cells are quickly destroyed by the spaser.

The spaser developed by the researchers has a gold core and a silica exterior coated with a uranine dye, which helps to track the location of the spaser. In order to target primarily tumor cells, the spaser has a folic acid (vitamin B) molecule attached to its surface. Tumors tend to exhibit large concentrations of a folate receptor on their cells, while healthy cells have low numbers of such receptors.

When injected into the blood stream, the spasers naturally stick to CTCs that they encounter. Once the spasers are given time to connect with CTCs, a laser light is then projected into the blood, heating up passing spasers and killing any CTCs that may be attached to them.

All this is still in the research phase and will have to be proven out in animal studies and hopefully further on humans. Nevertheless, the technology is potentially revolutionary and probably safe. “There is no other method to reliably detect and destroy CTCs,” in a statement said Dr. Mark Stockman, director of the Center for Nano-Optics and professor of physics at Georgia State. “This is the first. This biocompatible spaser can go after these cells and destroy them without killing or damaging healthy cells. Any other chemistry would damage and likely kill healthy cells. Our findings could play a pivotal role in providing a better, life-saving treatment option for cancer patients.”

Study in Nature Communications: Spaser as a biological probe…

Via: Georgia State…