RSC Advances Blog

In a study led by Ko and colleagues at the Department of Dental Materials, School of Dentistry, Kyung Hee University, Korea, researchers armed graphene QDs with two therapeutic moieties: a HER-targeting antibody meant to help the therapeutic QDs find HER2-expressing breast cancer cells; and doxorubicin (DOX) – a chemotherapeutic drug used widely in treating breast cancer.

Consistent with previously established criteria (size, shape etc.) for drug carriers, the current study found that the estimated size of 222 nm makes the nanocarriers good candidates for further development toward diagnostic and therapeutic applications. Further, the nanocarriers had excitation and emission wavelengths of 370 nm and 450 nm respectively, making them glow in the ultraviolet range and as a result, optimal for medical imaging applications. The research team showed through chemical binding analysis that anti-HER antibodies were firmly bound to the QDs, and that the QDs were hydrophilic. The team conducted thermal stability studies and showed that the nanocarriers were stable at temperature ranges  much greater than the physiological body temperature range.

The study also analyzed whether the therapeutic nanocarriers were able to specifically target and enter breast cancer cells, release the DOX payload under specific pH and temperature conditions, and subsequently induce breast cancer cell death. Using a HER2-expressing breast cancer cell line, the team showed that the nanocarriers could kill cells in a dose dependent manner. A temperature of 37oC and pH of 5.5 were optimal for DOX release. Results in fluorescent microscopy studies suggested that DOX was released immediately after the nanocarriers entered HER2-expressing cells.

This study proposes that graphene-based QDs, when armed with anti-HER antibodies and DOX, have great potential for translation. In addition, with biomarker-based treatment decisions entering clinical practice in oncology settings, QD-based therapeutic nanocarriers are likely to have a notable impact on cancer therapy.
Read the full article here:

Graphene quantum dot-based theranostic agents for active targeting of breast cancer
N. R. Ko, M. Nafiujjaman, J. S. Lee, H.-N. Lim,a Y.-k. Lee and I. K. Kwon