Enhanced Radiation Therapy of Gold Nanoparticles in Liver Cancer

Gold nanoparticles (GNPs) were widely used in X-ray imaging and radiation therapy due to strong photoelectric effects and secondary electrons under high energy irradiation. As liver cancer is one of the most common forms of cancer, the use of GNPs could enhance liver cancer radiotherapy. We synthesized polyethylene glycol (PEG)-coated GNPs of two different sizes by chemical reduction reaction. Blood stability, cellular uptake, cytotoxicity and radiation therapy were investigated. A 3-5 nm red shift of SPR caused by interactions between PEG-coated GNPs and plasma indicated their good stability. Cellular uptake assay showed that PEG-coated GNPs would enhance an appreciable uptake. GNPs preferred to combine with blood proteins, and thus induced the formation of 30-50 nm Au-protein corona. GNPs were endocytosed by cytoplasmic vesicles, localized in intracellular region, and presented concentration dependent cell viability. Clonogenic assay illustrated that the PEG-coated GNPs could sensitize two liver cancer cell lines to irradiation.