Theranostics, as the name suggests, is a device/system that acts in aiding diagnosis as well as therapy. Theranostics are the current trend in cancer research for a few years now. Researchers are trying more and more to develop materials with both diagnostic and therapeutic properties.
In the quest for one such theranostic material, researchers from the University of Cincinnati have discovered a new nanostructure that has outstanding properties for detecting and destroying cancer cells.
Discovered in 2013, the new SERS “nanotag”, as it is called works on the principle of surface-enhanced Raman spectroscopy (SERS) for detection of single molecules. SERS works on the principle of amplification of scattered light signals from single molecules. Usually some metals such as gold or silver are used for the amplification of the signals.
However, the process is highly sensitive and fraught with challenges, including difficulties with reproducibility, signal stability and a lack of quantitative information.
For designing the nanotag the team improved upon previous research that showed some promise towards SERS applications.
It was found that greater enhancement was observed from molecules residing within a one-nanometer gap between a structure with a smooth metallic core and shell. But this one nanometer gap is often difficult and expensive to produce, resulting in a lack of widespread use. Other popular research used gold nanostars, a star-fruit shaped gold nanoparticle structure that allowed greater enhancement of signals.
Inspired by these two reports, the team created a structure comprised of a smooth inner metallic core surrounded by a spiky metallic outer shell with a three nanometer spacing.
“The newly created nanotag produced 10 times greater signal enhancement compared to smooth-shell core structures, making it possible to detect minute amounts of organic molecules, such as DNA, for particular diseases”, said Laura Sagle, an assistant professor of chemistry who led the team.
What’s more, this nanotag was also capable of generating heat upon incident radiation that can be used to kill cancer cells. Its high surface area also can be used to carry drugs to achieve higher destruction of cancer.
“This allows you to target, image and release drugs all with one device,” Sagle explained.
While the discovery itself was extremely novel, the researchers were t a loss in understanding what generated the promising data or how to best optimize it.
The came Zohre Gorumnez, a fourth year PhD student who is credited with conducting nearly three years of complex and detailed calculations to better understand the new nanotag.
“It was calculations that no one on campus had done before,” With Zohre’s calculations, it was a much better paper showing we made something new, it showed better properties and we understand to some degree why,” explained Sagle.
The discovery of the nanotag accompanied with data obtained from calculation sure hold promise future biomedical applications.