Study of the dose response of the system ferrous ammonium sulfate–sucrose–xylenol orange in acid aqueous solution

•The system ferrous-sucrose-xylenol is reproducibility with less than 5% error.•The dosimeter has low cost and easy readout using UV-vis spectrometry, and the response is stable for several days.•The system proposed is suitable for low irradiation doses.

An aqueous solution of ammonium ferrous sulfate–sucrose–xylenol orange in sulfuric acid (FSX) is proposed as a dosimetric system for the processes of gamma irradiation in a range between 0.3 and 6 Gy.This system is based on the indirect oxidation of ferrous ion by an organic compound (sucrose) to ferric ion and on the formation of a color complex of Fe3+ in an acidic medium with xylenol orange (a dye). After gamma radiation, an observable change occurs in the color of the system.Irradiation was executed at three different temperatures (13 °C, 22 °C, and 40 °C). A spectrometric readout method at 585 nm was employed to evaluate the system׳s dose response. In all of the cases analyzed, the responses had a linear behavior, and a slight effect of irradiation temperature was observed. Post-irradiation response was also evaluated and showed the stability of the solutions 24 h after the irradiation.The results obtained suggest that FSX might be used as a dosimeter for low doses of gamma irradiation because it provides a stable signal, good reproducibility, and an accessible technique for analysis.