Balaashwin Babu1,Elayaraja Kolanthai1,Craig Neal1,Shreya Pawar1,Agastya Mittal1,Melanie Coathup1,Sudipta Seal1
University of Central Florida1
Balaashwin Babu1,Elayaraja Kolanthai1,Craig Neal1,Shreya Pawar1,Agastya Mittal1,Melanie Coathup1,Sudipta Seal1
University of Central Florida1
Space exploration is reaching new heights as we traverse beyond low earth orbit. In this extreme environment, radiation induced health issues will be a major concern. The ability to induce higher levels of free radicals and reactive oxidative species (ROS) are factors to be addressed. Ceria nanoparticles (CNPs) can provide a means to scavenge ROS; free radicals known to cause cell apoptosis and thus may serve as a radioprotectant. Further, conjugation of CNP to the drugs used to treat osteoporosis such as bisphosphonates, may offer a possible solution to space-induced osteopenia, and provide a dual functionality that can protect the bone cells from ROS and slow down overall bone loss. Current results indicate high Ce<sup>3+</sup> structural confirmation of ceria nanoparticles using a wet-chemical synthesis. The synthesized nanoparticles were then conjugated with risedronate, a third-generation bisphosphonate. Three experimental combinations including, 1,1'-carbonyldiimidazole (CDI) linker only, CDI + polyethyleneimine (PEI), and CDI + diamine were confirmed to be successfully conjugated through UV/Vis characterization. Superoxide inhibition results show that all three conjugated products displayed higher antioxidant properties as tested using a superoxide dismutase assay inhibition kit. Preliminary microwave radiation studies indicated that CNP was able to be used as a radioprotectant as it prevented changes in drug chemistry as detected by UV/Vis spectra after exposure to 60 seconds of microwave radiation. Finally, in vitro cell studies using human mesenchymal stem cells showed excellent viability when exposed to all combinations of drug and CNP at 50ug concentration as demonstrated using an MTT colorimetric assay. These results indicate ceria nanoparticles show promise as a radioprotectant material that may also work well as a drug encapsulant. Further studies are necessary to investigate this further.