THE CALCINATION TEMPERATURE EFFECT ON THE ANTIOXIDANT AND RADIOPROTECTION PROPERTIES OF CeO2 NANOPARTICLES

The CeO₂ nanoparticles are very interesting to be studied as biomedical materials due to its unique physical and chemical properties. The non-stoichiometric properties of CeO₂ play a role in the redox/catalytic processes that scavenging free radicals. These properties make CeO₂ nanoparticles as being potentially antioxidant and radioprotector materials. In this paper, we report the calcination temperature effect on the antioxidant properties and  radioprotective effect of CeO₂ nanoparticles synthesized by precipitation method. The CeO₂ nanoparticles were synthesized by precipitation method at various calcinations temperatures (300^oC – 700^oC). The formation of CeO₂ nanoparticles and crystallite size was analyzed using X-ray diffractometers. The DPPH method was used to investigate antioxidant properties of CeO₂.  Dose Enhancement Factor (DEF) of CeO₂ nanoparticles were determined by measurement of the absorbed dose of X-ray radiation (Linac 6 MV 200 MU). X-ray diffraction pattern showed formation of cubic fluorite of CeO₂ nanoparticles with crystallite size in the range 9 nm-18 nm.  Calcination temperature of 500^oC resulted in CeO₂ nanoparticles with the best antioxidant properties and lowest DEF value. The radioprotection effect of CeO₂ nanoparticles was evaluated based on Escherichia coli survival toward X-ray radiation with a dose of 2 Gy. The CeO₂ nanoparticles increased Escherichia coli survival of about 24.8% order.  These results suggested that CeO₂ nanoparticles may potentially be as radioprotector of X-ray Linac 6 MV.

Keywords: Antioxidant, CeO₂ nanoparticles, Dose Enhancement Factor (DEF), radioprotector