Use of Hydroxyapatite Prepared by Sol-Gel Method for Gamma Ray and Electron Beam Dosimetry

In this research, radiation dosimetry was made through measuring free radicals induced in synthetic hydroxyapatite (HAP) using EPR spectroscopy. At the first step, the hydroxyapatite nano-powders were synthesized via sol-gel method. The produced powders were passed through a thermal treatment, weighted and packed. Then, the samples were irradiated at different dose rates using 60Co γ-ray and 10MeV electron beam radiation at a high dose range. The EPR signal intensity of hydroxyapatite samples were measured at room temperature in the air. Subsequently, the variations of the EPR signal intensities were constructed as peak-to-peak signal amplitude and were compared with alanine and bone powder samples. The results showed that the EPR signal intensity of the HAP samples are several times higher than alanine and bone powder and are saturated at the higher dose rates in comparison with other species.