Octopod PtCu Nanoframe for Dual-Modal Imaging-Guided Synergistic Photothermal Radiotherapy.Heavy atom nanoparticles have high X-ray absorption capacity and near infrared (NIR) photothermal conversion efficiency, which could be used as radio-sensitizers.  We hypothesized that concave PtCu octopod nanoframes (OPCNs) would be an efficient nanoplatform for synergistic radio-photothermal tumor ablation.  Methods: In this study, we newly exploited a folic acid-receptor (FR) mediated photothermal radiotherapy nanoagent base on OPCNs.  OPCNs were synthesized with a hydrothermal method and then modified with polyethylene glycol (PEG) and folic acid (FA).  A series of physical and chemical characterizations, cytotoxicity, targeting potential, endocytosis mechanism, biodistribution, systematic toxicological evaluation, pharmacokinetics, applications of OPCNs-PEG-FA for in vitro and in vivo infrared thermal imaging (ITI)/photoacoustic imaging (PAI) dual-modal imaging and synergistic photothermal radiotherapy against tumor were carried out.  Moreover, the as-synthesized OPCNs-PEG-FA exhibited remarkable photothermal therapy (PTT) and radiotherapy (RT) synergistic tumor inhibition when treated with NIR laser and X-ray.  Conclusion: A novel multifunctional theranostic nanoplatform based on OPCNs was designed and developed for dual-modal image-guided synergistic tumor photothermal radiotherapy.
THERM