PEGylated hollow gold nanoparticles for combined X-ray radiation and photothermal therapy in vitro and enhanced CT imaging in vivo.

Up until now, hollow gold nanoparticles (HGNPs) with a spherical cavity have garnered much interest as theranostic agents in cancer therapy due to their high X-ray absorption and photothermal conversion ability. Herein, we describe the design of PEGylated hollow gold nanoparticles (mPEG@HGNPs) for combined X-ray radiation and photothermal therapy in vitro and enhanced computed tomography (CT) imaging in vivo using a breast tumor model. In vitro results revealed that mPEG@HGNPs could achieve a synergistic antitumor effect when irradiated by combined X-ray radiation and 808 nm near infrared laser light. Furthermore, mPEG@HGNPs exhibited a favorable tumor targeting effect and good CT contrast enhancement in both xenografted and orthotopic breast tumor models, due to the stealth effect of PEG which increased the enhanced permeability and retention (EPR) effect. These results suggest that mPEG@HGNPs may serve as multifunctional nanocomposites for cancer combination therapy and, thus, should be further studied.