Gamma-irradiated EPR response of nano-structure hydroxyapatite synthesised via hydrolysis method.

In this paper, the gamma-irradiated EPR responses of hydroxyapatite (HAP) samples were investigated from a dosimetric point of view. For this purpose, nano-structure hydroxyapatite was synthesised via a hydrolysis method. A portion of the produced powder was annealed at 600 °C for 4 h. All the samples were irradiated under the (60)Co gamma-ray source at different absorbed doses from 0.1 to 45 kGy. EPR signal intensities of HAP samples were measured at room temperature in air. Subsequently, the EPR signal intensities were constructed as a function of radiation dose and were compared with the results of bone powder samples. The results show that the EPR responses of non-annealed HAP samples are higher than others for several times.