In Vitro Cytotoxicity of Rare Earth Oxide Nanoparticles for Imaging Applications

The in vitro cytotoxicity and cellular uptake of commercially available doped YVO4 were evaluated in RAW 264.7 macrophages using the MTT assay. The results indicated that 20–50 nm diameter samarium-doped YVO4 showed significant toxicity at concentrations of 25 μg/mL and higher; samples of the same material functionalized with COOH showed less cytotoxicity. At concentrations of 25–100 μg/mL, 20–50 nm erbium-doped YVO4 showed less toxicity compared with 20–50 nm samarium-doped YVO4. Ten nanometer samples showed no toxicity at concentrations of 100–600 μg/mL. The cytotoxicity of rare earth nanoparticles in macrophages is dependent, at least in part, on size and surface functionalization.