Cytotoxicity and Cellular Uptake of Gold Nanoparticles in Breast Cancer Cells Quantified Using Total Reflection X-Ray Fluorescence

The field of nanotoxicity is continuously expanding as researchers seek to understand potential consequences of AuNP use in the medical field. Many current results examining cytotoxicity trends with varying nanoparticle parameters lack consistency and rely on methods to measure uptake that have been previously noted as unreliable. In this work, 10 and 50 nm diameter gold nano-spheres and -rods are compared while also measuring absolute gold uptake. The toxicity of naked AuNP in epithelial breast cancer cells were measured with flow cytometry while cellular uptake was analyzed with total reflection X-ray fluorescence (TXRF) spectroscopy. Confirming results seen in many studies, spheres were taken up more effectively and exhibited lower toxicity. Measuring the absolute gold, 10 nm shapes were up to 6% more toxic. Modelling the toxicity, both the Hill and linear-quadratic models are more suitable than the exponential model (p<0.05) where the Hill model is proposed for future use.