Hybrid graphene oxide as carrier of doxorubicin: cytotoxicity and preliminary in vivo assays against bladder cancer

Two types of graphene oxide (GO) hybrids were synthesised for the administration of doxorubicin (DOX, named GO-CO-DOX) and interfering RNA - siRNA (named GO-PEG-PEI/siRNA). These nanomaterials were used for intervention on vascular endothelial growth factor (VEGF) that represents an important strategy to block the formation of new vessels to inhibit cancer progression. For the delivery of DOX, it was incorporated into GO, while for the delivery of siRNA, GO was covalently bonded with the cationic polyethyleneimine (PEI) and then complexed with siRNA. The nanostructures were characterised by attenuated total reflection ATR-FTIR, zeta potential, x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), and transmission electron microscopy (TEM). The cytotoxicity studies with GO-PEG-PEI and GO-PEG-PEI/siRNA systems showed that both formulations have IC50 values of around 100 μg ml−1. The systems were administered in vivo to investigate their antitumor effects against non-muscle-invasive bladder cancer (NMIBC) and showed to be promising for the treatment of NMIBC.