Dimethyl sulfoxide, diethyl fumarate solution for high dose dosimetry

Background: Dosimetry is a fundamental part of the radiaon processing industry. Aqueous inorganic dosimeters have been used for gamma radiaon dosimetry such as standard ferrous sulfate dosimeter. The purpose of this study was to invesgate the effect of gamma radiaon on the diethyl fumarate DEF in dimethyl sulfoxide DMSO soluon and its possible use in chemical dosimetry. Materials and Methods: Three soluons having different concentraons of DEF were prepared (5, 10 and 20%) and exposed to various gamma doses. Irradiaon was carried out using ROBO facility of 60Co gamma ray. Absorbance was measured using Melton Roy 1201 UV-VIS spectrophotometer. Results: The absorpon spectra of irradiated soluon showed broad absorpon bands between (325-400nm) with a shoulder at 332 nm. The absorbance increased with increasing the dose. Good response and linear relaonship were found between absorbed dose and absorbance of 10% and 20% DEF concentraon in the range of 0-225 kGy at the measured wavelength. Good dose rate independence was observed in the range of 14-33 kGy/h. It was noced that irradiated samples had a good stability in darkness. Whereas, the response was affected during the storage in day light. This response was found to be depended on the irradiaon temperature within the range of 18- 52 0C. Conclusion: Our measurements showed that the ability of using the soluon of diethyl fumarate DEF in dimethyl sulfoxide DMSO as a high dose radiaon dosimetry. The useful dose range for 10% and 20% DEF of concentraons is up to 225 kGy. Nevertheless, the correcon of temperature for roune dosimetry measurements should be taken into account.