This work focused on the analysis of the temporal diffusion of ferric ions through PVA-GTA gel dosimeters. PVA-GTA gel samples, partly exposed with 6 MV X-rays in order to create an initial steep gradient, were mapped using magnetic resonance imaging on a 7T MRI scanner for small animals. Multiple images of the gels were acquired over several hours after irradiation and were analyzed to quantitatively extract the signal profile. The spatial resolution achieved is 200 lm and this makes this technique particularly suitable for the analysis of steep gradients of ferric ion concentration. The results obtained with PVA-GTA gels were compared with those achieved with agarose gels, which is a standard dosimetric gel formulation. The analysis showed that the diffusion process is much slower (more than five times) for PVA-GTA gels than for agarose ones. Furthermore, it is noteworthy that the diffusion coefficient value obtained through MRI analysis is significantly consistent with that obtained in separate study Marini et al. (Submitted for publication) using a totally independent method such as spectrophotometry. This is a valuable result highlighting that the good dosimetric features of this gel matrix not only can be reproduced but also can be measured through independent experimental techniques based on different physical principles.
Analysis of spatial diffusion of ferric ions in PVA-GTA gel dosimeters through magnetic resonance imaging / M. Marrale, G. Collura, S. Gallo, S. Nici, L. Tranchina, B. Abbate, S. Marineo, S. Caracappa, F. d'Errico. - In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION B, BEAM INTERACTIONS WITH MATERIALS AND ATOMS. - ISSN 0168-583X. - 396(2017 Apr), pp. 50-55.
|Titolo:||Analysis of spatial diffusion of ferric ions in PVA-GTA gel dosimeters through magnetic resonance imaging|
GALLO, SALVATORE (Corresponding)
|Parole Chiave:||Gel dosimetry; PVA gel; Agarose gel; Magnetic resonance imaging; Clinical photons beam|
|Settore Scientifico Disciplinare:||Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)|
Settore FIS/01 - Fisica Sperimentale
|Data di pubblicazione:||apr-2017|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.nimb.2017.02.008|
|Appare nelle tipologie:||01 - Articolo su periodico|