PEGylated iron oxide-gold core-shell nanoparticles for tumor-targeted delivery of Rapamycin

Rapamycin analogs are approved by the FDA for breast and renal cancer treatment. Hence, the possibility of nanoparticle-mediated delivery of Rapamycin could be examined. In the present study, PEGylated Gold-core shell iron oxide nanoparticles were used for the targeted delivery of Rapamycin, and R-Au-IONPs were formulated. SEM, XRD, and FTIR determined the smooth spherical morphology, and compositional structure, and confirmed the conjugation of Rapamycin onto the NPs. The in vitro drug release study showed a controlled release of the drug over time. R-Au-IONPs showed significant cytotoxicity in MCF 7 cells. Anti-proliferative assays such as trypan blue dye exclusion assay, microscopy, Fluorescent staining, and clonogenic assays were performed. NH staining, Rhodamine 123 staining, PS externalization, and the cleavage of PARP protein by western immunoblot assays confirmed the induction of apoptosis. The mechanism of R-Au-IONP-induced cell death was analyzed by flow cytometry. Our in-vitro study, on the impact of R-Au-IONPs on cell viability in the human breast adenocarcinoma cell line (MCF-7), confirms the efficacy of drug delivery using the nanoparticle system. Further results implied the induction of apoptosis. This drug delivery system using Rapamycin could be a potential candidate in the treatment of breast cancer.