Effect of inorganic salts and matrix crosslinking on the dose response of polymer gel dosimeters based on acrylamide
Fecha
2018-07-17
Autores
Chacón, David
Strumia, Miriam
Valente, Mauro
Mattea, Facundo
Título de la revista
ISSN de la revista
Título del volumen
Editor
Elsevier Ltd
Resumen
The use of additives in polymer gel dosimeters to enhance their sensitivity or to improve their performance is of
great importance for their application in radiomedicine. Inorganic salts have been used as additives with this
purpose; however, their presence in the dosimeters induce severe modifications in their mechanical properties
and consequently in their capabilities to maintain a stable dose distribution with time. Most studies in this area
conclude in the need to use chemical modifications of the species responsible for the mechanical properties of
the dosimeters, which in most cases is a gelatin matrix. In this study, a covalent crosslinking of the gelatin matrix
of PAGAT dosimeters doped with different inorganic salts, namely MgCl2, CaCl2 and MnCl2 has been carried out.
The mechanical properties, X-ray sensitivity and dose distribution stability in these materials were compared to
those of PAGAT. The results indicated a compromise between the crosslinking of the gelatin structure and the
sensitivity of the dosimetric material. Therefore, the proper selection of the degree of crosslinking and the
inorganic salt concentration must be considered. An enhanced dosimeter was obtained by adding MgCl2 with a
1 M concentration and by crosslinking the gelatin matrix with glutaraldehyde at a 0.08% / w v concentration. This
material presented a 75% enhanced sensitivity relative to PAGAT and similar temporal stability and spatial
stability in 2D dose distributions.
Descripción
Palabras clave
Salts, Polymers, Sales, Polímeros