Gold Nanorod-Assembled PEGylated Graphene-Oxide Nanocomposites for Photothermal Cancer Therapy

Gold nanorod-attached PEGylated graphene-oxide (AuNR-PEG-GO) nanocomposites were tested for a photothermal platform both in vitro and in vivo. Cytotoxicity of AuNR was reduced after encapsulation with PEG-GO along with the removal of cetyltrimethylammonium bromide (CTAB) from AuNR by HCl treatment. Cellular internalization of the CTAB-eliminated AuNR-PEG-GO nanocomposites was examined using dark-field microscopy (DFM), confocal Raman microscopy and transmission electron microscopy (TEM). To determine the photothermal effect of the AuNR-PEG-GO nanocomposites, A431 epidermoid carcinoma cells were irradiated with Xe-lamp light (60Wcm(-2)) for 5min after treatment with the AuNR-PEG-GO nanocomposites for 24h. Cell viability significantly decreased by ~40% when the AuNR-PEG-GO-encapsulated nanocomposites were irradiated with light as compared with the cells treated with only the AuNR-PEG-GO nanocomposites without any illumination. In vivo tumor experiments also indicated that HCl-treated AuNR-PEG-GO nanocomposites might efficiently reduce tumor volumes via photothermal processes. Our graphene and AuNR nanocomposites will be useful for an effective photothermal therapy.The National Research Foundation of Korea supported this work through grant numbers R11-2008-0061852 and K20904000004-12A0500-00410. The Nano Material Technology Development Program also supported this work, through the National Research Foundation of Korea, funded by the Ministry of Education, Science, and Technology (grant number 2012035286). This research was also partially supported by the Agency for Defense Development through Chemical and Biological Defense Research Center and the Development of Characterization Techniques for Nano-materials Safety Project of KRCF. This work was supported by the National Research Foundation (NRF) grant funded by the Korea Government (MEST) nos. 2011-0017435 and the Korea government [MSIP] [no. 20090083525]