Effect of Modification Protocols on the Effectiveness of Gold Nanoparticles as Drug Delivery Vehicles for Killing of Breast Cancer Cells

The current study evaluated the potential of gold nanoparticles (AuNPs) for the delivery of Taxol to breast cancer cells (T47D) using an in vitro cell culture model. For this study, new loading approaches and novel chemical attachments were investigated. Five different gold nanoparticle-based complexes were used to determine their cytotoxicity towards T47D cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay. There was no significant decrease (P>0.05) in cell viability when T47D cells were treated with AuNPs that did not contain Taxol. However, cells were significantly killed by gold nanoparticles chemically conjugated to Taxol using three different approaches and one novel hybrid AuNP-Taxol nanoparticle, wherein no chemical bonds were involved. These Taxol-loaded AuNPs were more effective at inducing cell death in vitro than a solution of free Taxol used to treat cells. This result demonstrated that Taxol could be released from the particles in the cell culture media for subsequent therapeutic action. Additionally, the experiments proved that the Taxol-loaded AuNPs were more toxic in a dose dependent manner than Taxol as a formulation for the treatment of breast cancer cells. The results of this study suggest that gold nanoparticles have potential for the efficient delivery of Taxol to breast cancer cells. This could provide a future solution as an alternative application method to overcome adverse side effects resulting from current high-dose treatment regimes.