Evaluation of fluorescent dye degradation indirectly induced by x-ray ionizing radiation

This work evaluated the fluorescent dye degradation indirectly induced by ionizing radiation with high energy photons (50 keV). Aqueous gels of agarose with low concentrations of Rhodamine 6G and Fluorescein were submitted to doses of x-ray radiation up to 200 Gy. The dye degradation was analyzed by fluorescence spectroscopy, using an excitation light-emitting diode with a peak wavelength of 462 nm. A rate equation model of fluorophores and radicals' species populations was developed to describe the degradation time behavior of the fluorescent solutions. The model suggests fluorescent dyes should be used in dosimetry.