Assessment of cytotoxicity profile of gadolinium oxide nanorods and the analogous surface-functionalized nanorods

Gadolinium (Gd) has a strong paramagnetic response and is used in advanced magnetic resonance imaging (MRI). Gd is used in the complex form in MRI, but these complexes lack in sensitivity, targeting, rapid elimination from the body, and low internalization into the cell. To replace these Gd complex, the nanostructure (NSs) form of Gd has emerged as a viable solution as the NSs are expected to increase cell uptake and biocompatibility. The cytotoxicity evaluation is the key component that needs to be addressed for translating NSs from the lab to the clinic, and their effect on the cells is a vast area of research. Hence, the present study reports the hydrothermal synthesis of gadolinium oxide nanorods (Gd2O3 NRs) and ex-situ functionalized with aspartic acid (Asp-Gd2O3 NRs). The cytotoxicity studies on two cells namely RAW 264.7 and MCF-7 was assessed in terms of cell viability, morphological changes, and cell cycle analysis. Both types of NRs were well characterized and it was found that Asp-Gd2O3 NRs exhibited enhanced hydrophilicity and dispersity. Cell viability assay revealed enhanced biocompatibility of Asp-Gd2O3 NRs with almost 75% viability even at a higher concentration of 250 µg ml−1. The morphological changes upon internalization of both NRs were done through fluorescent microscopy that revealed no significant change in the morphology of the cell or its nucleus. Further, the cell cycle studies again confirmed the biocompatible nature of these NRs. These results suggest that Asp-Gd2O3 NRs are well suited for therapeutic applications, such as thermal cancer therapy, due to their tunable shape, size, low toxicity, and the possibility of surface modification.