Gamma-irradiation of Fe(III)-APCAs

Chromatographic data recorded for gamma-irradiated samples of EDTA, Fe(III)-EDTA and Fe(III)-DTPA. Chromatographic peak intensity is converted to concentration using linear calibration plot of data collected for un-irradiated samples. Concentration of each species lost is converted to G-values for inter-comparison. G-values have been calculated using conversion factors and by differentiation of linear plots of increasing degradation with increasing dose. Study of the behaviour of irradiated Fe(III)-EDTA in oxygenated and nitrogenated environments has also been carried out, similar calculations have been performed. Chromatographic data was also recorded up to roughly 3 weeks after the irradiation to assess the stability of the remaining parent APCA species and the potential degradation products. The change in the peak intensity as a function of time has been plotted and analysed.