Processing and characterization of MAGIC-f gel with ultraviolet/visible light spectrophotometry

The use of dosimetric gel in radiotherapy for quality control and verification of the dose delivered to the patient has gained prominence, since it is still the only three-dimensional dosimetry method. Based on this concept, the present work had the objective of processing the MAGIC-f polymeric gel with addition of fluorescein and characterizing it with UV/Vis (ultraviolet/visible light) spectrophotometry. The characterization of the samples was done 2, 7 and 34 days after irradiation with 6 MV photons and wavelengths between 300 and 600 nm. The results showed that the higher the dose, the lower the absorbance intensity measured by the equipment due to the increased polymerization degree, a satisfactory and expected result. It could also be concluded that the higher the irradiation dose of the MAGIC-f gel, the lower the fluorescein absorbance intensity – even a few days after irradiation– due to the continuity of polymerization. The MAGIC-f dosimeter with fluorescein has shown to be very promising, but further tests will be necessary to evaluate other dosimetric properties, such as energetic and dose rate dependence.