Photothermal therapy of human glioma spheroids with gold-silica nanoshells and gold nanorods: a comparative study

摘要

The efficacy of gold-silica nanoshells (AuNS) and gold nanorods (AuNR) for photothermal therapy was investigated in an in vitro system consisting of hybrid murine macrophage/human glioma spheroids. Macrophages were used as delivery vectors for the nanoparticles. Hybrid spheroids were formed via centrifugation of human glioma cells and nanoparticle-loaded macrophages. Forty-eight hours post-centrifugation, the resultant 400 μm dia. spheroids were exposed to 808 nm laser light for 10 min. at irradiances ranging from 2 - 28 W cm~(-2). Treatment efficacy was evaluated from spheroid growth kinetics over a 14-day period. AuNS were shown to have greater efficacy compared to AuNR. For example, hybrid spheroids consisting of a 5:1 ratio of glioma cells to AuNS-loaded macrophages exhibited significant growth inhibition when subjected to irradiances of 7 W cm~(-2). In contrast, no growth inhibition was observed for the AuNR-macrophage hybrid spheroids, even at the highest irradiance investigated (28 W cm~(-2)). Growth inhibition was observed at 28 W cm~(-2) when the nanorod concentration was increased, i.e., by forming hybrid spheroids with a 2:1 ratio of glioma cells to macrophages.