Carbon nanotubes can allow Raman spectroscopy to be used as a technique for real-time detecting, tracking, and, with laser assistance, even killing cancer cells, according to researchers in the US.
The discovery could open up a new, battle front in the fight against cancer with the promise of a new generation of therapeutic agents beyond surgery, radiation, and conventional anticancer chemotherapy drugs.
Alex Biris of the University of Arkansas at Little Rock (UALR) is chief scientist at the Nanotechnology Center and is working with colleague in the medical sciences Vladimir Zharov, to develop the technique. They report details of their efforts in the latest issue of the Journal of Biomedical Optics.
"Until now, nobody has been able to fully understand and study in vivo and in real time how these nanoparticles travel through a living system," Biris said. "By using Raman spectroscopy, we showed that it is possible not only to monitor and detect nanomaterials moving through the circulation, but also to detect single cancer cells tagged with carbon nanotubes. In this way, we can measure their clearance rate and their biodistribution kinetics through the lymph and blood systems."
The technique the team has developed is known as in vivo Raman flow cytometry. Zharov says that it is showing promise for the detection and identification of a broad spectrum of nanoparticles with strong Raman scattering properties, such as cells, bacteria, and even viruses.
In the latest study, Biris, Zharov, and colleague Ekaterina Galanzha also in medical sciences injected a single human "HeLa" cancer cell containing carbon nanotube material into the tail vein of a lab rat. They were able to follow the cell through the rat's blood stream, lymphatic system, and tissues using a Raman spectrometer until it reached the rat's ear.
In a back-to-back paper, the researchers also discussed the potential of nanoparticles as tags for cancer cells in therapy, pointing out that a laser can be used to heat the nanoparticles directly and so kill the cancer cell to which they are attached.
"If we are able to target cancer cells using these nanomaterials, we can monitor where the cancer cells are specifically located, and then we can kill them," Biris explains. The hope would be that the cancer killing process would leave nothing behind but dead cancer cells and nanoparticles that would be flushed from the body with other waste products, although proof of principle on that aspect of the research remains to be carried out.