ESR measurement of carbonated hydroxyapatite for dosemeter

Seito, Hajime*; Yokozuka, Eri*; Oka, Toshitaka   ; Kitatsuji, Yoshihiro  ; Nagasawa, Naotsugu*

We have examined dosimetric characteristics of bio-inspired carbonated hydroxyapatite (COHAp), which is a main component of calcified tissues like tooth enamel. COHAp powder samples were exposed to gamma-ray with radiation doses ranging from 1 Gy to 1000 Gy at room temperature, and ESR spectra were measured immediately after irradiation and subsequently measured each 1 day during 90 days. The post-irradiation fading resulted in significant 20% decay of the signal amplitude, which stabilised within 7 days after irradiation, and the intensity approached a constant. The sample has good linear dose response in the experiment range of 10 Gy - 1000 Gy. Our results indicate that the COHAp materials is suitable for chemical dosimetry.