Bioconjugated plasmonic gold nanorod vesicles for cancer cell imaging and therapy

Abstract

The surfaces of gold nanorods synthesized by modified seed-mediated growth method were modified by polymer brushes, PLA and PEG to enhance the stability. Gold nanorods further self-assembled into plasmonic vesicles and were conjugated with monoclonal antibodies, namely anti-EpCAM to specifically target liver cancer cell line known as Hep3B which overexpressed EpCAM cell surface receptors. Optical properties of bioconjugated plasmonic gold nanorod vesicles were investigated and demonstrated through live cell imaging and photothermal therapy which proven the multifunctional roles of nanoparticles in biomedical applications.

As the longitudinal band of the self-assembled bioconjugated plasmonic gold nanorod vesicles fell in the NIR region where tissues absorption by blood and tissues were the least, they were able to scatter light strongly when uptake by Hep3B cells. Therefore by fine tuning of the aspect ratio, scattered light of different colours can be observed. This in turn contributed to bioimaging as it helps to distinguish cancerous cells. On the other hand, upon exposure to laser irradiation, bioconjugated plasmonic gold nanorod vesicles effectively converted light energy to heat energy and aid in localized heating effect which selectively killed Hep3B cells while leaving surrounding healthy cells unharmed. Additionally, future outlook of nanoparticles were also discussed so to bring nanotechnology to the next breakthrough.