pH-Metric study of gamma-irradiated table sugar for dosimetry purpose

Table sugar has been studied for a long time as a dosimeter in radiation accident and in high-dose dosimetry by using different analytical techniques especially electron paramagnetic resonance (EPR) and optical absorption spectrometry (OA). In this work, we report the results obtained by pH-metry on gamma-irradiated sugar. Table sugar samples were exposed to gamma radiation with doses of 0.1–58 kGy. Aqueous solutions of sugar were prepared with different concentrations ranged from 1% to 60% (w/w). It was found that sugar solutions showed strong decrease of pH up to concentration of 10% (w/w) followed by a slow decrease for the concentrations between 10 and 60% (w/w). Two possible mechanisms are proposed to explain the acidity increasing of the sugar solutions based on the existence of a carbonyl radical induced by gamma irradiation in solid table sugar with an open ring structure. Results for radiation response, post-irradiation change, reading temperature, dose-rate effect and repeatability are presented in this study. The results showed that pH-metric/sugar solution is an adequate high-dose dosimetric system in the dose range of 0.1–10 kGy.