Graphene for Drug Delivery & Cancer Therapy
The exploration of graphene in drug delivery and biomedicine was first initiated by the Hongjie Dai group at Stanford University (CA, USA) in 2008.[2,3] Motivated by the successes of using carbon nanotubes for a number of biomedical applications, they started to wonder whether graphene may also be an interesting material in drug delivery. An amine-terminated, branched PEG was used to functionalize GO, affording PEGylated nano-graphene (NGO-PEG) highly stable in physiological solutions. Aromatic anticancer drugs (e.g., SN38 and doxorubicin) were effectively loaded on the graphene surface via ϖ-ϖ stacking for intracellular drug delivery. Ultra-high drug loading efficiency was achieved owing to the extremely large surface area of graphene, which has every atom exposed on its surface.[2,3] Since then, several other groups have also paid attention to the graphene-based drug loading and delivery systems and published a number of interesting results.[5–7]
The in vivo study of graphene in animals was not reported until a recent paper by our group. In this work, PEGylated nano-graphene was labeled by a NIR fluorescence dye for in vivo fluorescence imaging, as the intrinsic photoluminescence of nano-graphene is too weak for in vivo imaging. The in vivo behaviors of NGO-PEG was investigated in several different xenograft tumor mouse models, showing surprisingly high passive uptake of graphene in tumors. Utilizing the strong optical absorbance of NGO-PEG in the NIR region, we carried out an in vivo photothermal treatment to kill tumors in the mouse model and achieved an ultra-efficient tumor photothermal ablation effect by intravenous administration of NGO-PEG and low-power NIR laser irradiation on the tumor. This is the first success of using graphene for in vivo cancer therapy. A later work by another group further showed that nano-graphene was significantly better than carbon nanotubes in inducing photothermal death of U251 human glioma cells in vitro.
Nanomedicine. 2011;6(2):317-324. © 2011 Future Medicine Ltd.
Cite this: Graphene in Biomedicine: Opportunities and Challenges - Medscape - Mar 01, 2011.