Studies of radio-chromic PVA-GTA Fricke gels for dosimetry in X-rays external radiation therapy.
Gallo S., Gambarini G., Lenardi C., Artuso E., Brambilla M.G., Lizio D., MontiA.F., Pignoli E., TorresinA., Veronese I.
V - Biofisica e fisica medica
GSSI Ex ISEF - Aula B - Mercoledì 25 h 10:00 - 13:00
» Download abstract
The experimental activities here reported are focused on the analysis of the clinical applications of Fricke gel (FG) dosimeters produced with Polyvinyl alcohol (PVA) and glutaraldehyde (GTA). The sample was irradiated with x-rays generated by a LINAC. UV-Vis absorbance spectra collected at consecutive times post-irradiation showed that a time of approximately 15 min is sufficient to reach a stable absorbance value, indicating the achievement of a chemical equilibrium. The analysis of the change of the absorbance spectra shape with the cumulated dose demonstrated that a linear dose-response curve of PVA-GTA-FG dosimeters is obtained in the entire investigated dose interval by properly choosing the wavelength used for the absorbance measurements. PVA-GTA-FG dosimeters proved to be water-equivalent and characterized by a response independent of the energies and dose rates. These findings suggested that PVA-GTA-FG are promising tools for clinical dosimetry.