Variable and Biological Effects of Cerium Oxide Nanoparticle Formulations.

Cerium oxide nanoparticles (CeNPs) exhibit redox capacity with efficacy in disease models of oxidative stress. Here we compare, in parallel, three CeNP formulations with distinct chemical stabilizers and size. assays revealed antioxidant activity from all the CeNPs, but when administered to mice with a reactive oxygen species (ROS) mediated model of multiple sclerosis, only custom-synthesized Cerion NRx (CNRx) citrate-EDTA stabilized CeNPs provided protection against disease. Detectable levels of ceria and reduced ROS levels in the brains of CNRx CeNP-treated mice imply that these CeNPs' unique properties influence tissue distribution and subsequent biological activity, suggesting why differing CeNP formulations yield different effects in various models. Further, the variation in vs results with these CeNP formulations highlights the necessity for studies that confirm whether the inherent catalytic activity of CeNPs is maintained after transport and distribution within intact biological systems.