Polymer-Supported Gold Nanoparticle Radiosensitizers with Enhanced Cellular Uptake Efficiency and Increased Cell Death in Human Prostate Cancer Cells

Polymer-supported gold nanoparticles (AuNPs) show increased stability to biological and physiological conditions compared to free AuNPs. Here, we demonstrate an increase in the cellular uptake efficiency of Au by the DU145 human prostate cancer cell line for 4.5 nm AuNPs loaded onto 100 nm (13%) and 200 nm (18%) polystyrene particles compared to free AuNPs (4%). Composite formulations were well tolerated by the cell with minimal direct toxicity. Under X-ray irradiation, significant radiation dose enhancement of 1.23 at 4 Gy was observed, outperforming previously reported radiosensitization experiments using free AuNPs, demonstrating the potential application of polymer-supported AuNPs as radiosensitizers.