Technical Note: Preliminary investigations into the use of a functionalised polymer to reduce diffusion in Fricke gel dosimeters

Abstract

Because this initial method of chemically bonding xylenol orange to polyvinyl alcohol has inherently low conversion, the improvement on existing gel systems is minimal when compared to the drawbacks. More efficient methods of functionalising polyvinyl alcohol with xylenol orange must be developed for this system to gain clinical relevance.

Characterization of radiochromic poly(vinyl-alcohol)–glutaraldehyde Fricke gels for dosimetry in external x-ray radiation therapy

“…Such features, together with the low Fe 3+ diffusion rate characterizing the PVA-GTA gel networks [19][20][21], make these dosimeters promising tools in external x-ray radiation therapy applications. Further studies are currently in progress with the aim to improve the precision of the optical response of PVA-GTA FG dosimeters irradiated to low doses (i.e.…”

“…Among the various strategies proposed for limiting this drawback [14][15][16], recently, formulations based on gel matrices of poly(vinyl-alcohol) (PVA) chemically crosslinked with glutaraldehyde (GTA) have shown improvements as compared to FGs with natural matrices [17,18]. Accordingly, the interest toward PVA-GTA FG dosimetry is gaining importance, as attested to by the increasing literature about this topic [19][20][21][22][23][24][25][26][27].…”

Does the gelation temperature or the sulfuric acid concentration influence the dosimetric properties of radiochromic PVA-GTA Xylenol Orange Fricke gels?

“…In an attempt to improve the dosimeter, poly(vinyl alcohol) (PVA) cross-linked by glutaraldehyde (GTA) was recently introduced as a matrix for the preparation of Fricke gels (Jin et al, 2012;Ruijia et al, 2010;d'Errico et al, 2017;Marini et al, 2017;Marrale et al, 2017;Boase et al, 2018;Smith et al, 2015;Gallo et al, 2019;Collura et al, 2018;Gallo et al, 2017;Eyadeh et al, 2018b;Rabaeh et al, 2018). PVA cross-linked with GTA is a hydrogel that, due to its crosslinks within the polymeric chains, absorb and retain large amount of water but do not dissolve in aqueous solutions (Hennink and van Nostrum, 2012).…”

Multifactorial study and kinetics of signal development in ferrous–methylthymol blue–gelatin gel dosimeters

“…Diffusion of Fe 3+ after irradiation leads to dose image deterioration and is the main drawback of the system. Multiple approaches have been tried to limit the Fe 3+ diffusion: use of different ligands, substitution of gelatin for polyvinyl alcohol (PVA), chemical immobilization of xylenol orange onto the gel matrix material, and the introduction of nanoparticles . While most of these methods reduce the Fe 3+ diffusion, significant sensitivity reduction is observed, relative to the ferrous–xylenol orange–gelatin (FXG) dosimeter.…”