Gold Nanorods Conjugated with Doxorubicin and cRGD for Combined Anti- cancer Drug Delivery and PET Imaging

licenses/by-nc-nd/3.0/). Reproduction is permitted for personal, noncommercial use, provided that the article is in whole, unmodified, and properly cited. Received: 2012.06.18; Accepted: 2012.07.11; Published: 2012.08.06 A multifunctional gold nanorod (GNR)-based nanoplatform for targeted anticancer drug de-livery and positron emission tomography (PET) imaging of tumors was developed and char-acterized. An anti-cancer drug (i.e., doxorubicin (DOX)) was covalently conjugated onto PEGylated (PEG: polyethylene glycol) GNR nanocarriers via a hydrazone bond to achieve pH-sensitive controlled drug release. Tumor-targeting ligands (i.e., the cy-clo(Arg-Gly-Asp-D-Phe-Cys) peptides, cRGD) and 64Cu-chelators (i.e., 1,4,7-triazacyclononane-N, N’, N’’-triacetic acid (NOTA)) were conjugated onto the distal ends of the PEG arms to achieve active tumor-targeting and PET imaging, respectively. Based on flow cytometry analysis, cRGD-conjugated nanocarriers (i.e., GNR-DOX-cRGD) exhibited a higher cellula