Polymer gel dosimeter based on itaconic acid

Abstract

A new polymeric dosimeter based on itaconic acid and N, N'-methylenebisacrylamide was studied. The preparation method, compositions of monomer and crosslinking agent and the presence of oxygen in the dosimetric system were analyzed. The resulting materials were irradiated with an X-ray tube at 158cGy/min, 226cGymin and 298cGy/min with doses up to 1000Gy. The dosimeters presented a linear response in the dose range 75-1000Gy, sensitivities of 0.037 1/Gyat 298cGy/min and an increase in the sensitivity with lower dose rates. One of the most relevant outcomes in this study was obtaining different monomer to crosslinker inclusion in the formed gel for the dosimeters where oxygen was purged during the preparation method. This effect has not been reported in other typical dosimeters and could be attributed to the large differences in the reactivity among these species.

Hydrogels for Three-Dimensional Ionizing-Radiation Dosimetry

“…Various studies have analyzed the MRI response of polymer gels for possible application in radiotherapy dose mapping ( [58,63] and references therein). In particular, polymer gels have been investigated for dosimetry in conformal therapy, IMRT, IMAT, IGRT, VMAT and tomotherapy [55,70,83,88,102,, small photon fields [136][137][138], stereotactic radiosurgery [55,[139][140][141][142], 60-cobalt source [143,144], brachytherapy [55,85,92,[145][146][147][148][149], cyberknife [150], gamma-knife [151], low-energy X-rays [152,153], high-LET and proton therapy [55,154,155], boron capture neutron therapy [55,[156][157][158][159], for interface dosimetry in the presence of tissue inhomogeneities [55,160,161], for X-ray tubes [162] and for diagnostic nuclear medicine [163]. Recently, polyacrilamide gels were proposed for dosimetry and end-to-end test for MRI-linac apparatus [164]…”

Raman spectroscopy as a tool to evaluate oxygen effects on the response of polymer gel dosimetry

“…However, the use of more direct techniques like Raman spectroscopy could provide a precise insight on changes in the chemical structure of sample constituents and, therefore, offers a unique tool to study the polymerization taking place in the dosimeters. In that regard, Baldock et al (Baldock et al, 1998) were the first to use Raman spectroscopy for the study of monomer consumption in irradiated polymer gel dosimeters, and since then several studies on the use of Raman spectroscopy with different polymer gel dosimetry were reported (Adenan et al, 2014;Huang et al, 2013;Jirasek, 2010;Mattea et al, 2015a;Rintoul et al, 2003), which show the potentiality of the technique to evaluate the consumption of each reactive species separately, and also to study more complex mechanisms taking place in the gels like the interaction between typical antioxidants with the monomers, gelatin or other species present in the dosimeter.…”

Effect of inorganic salts and matrix crosslinking on the dose response of polymer gel dosimeters based on acrylamide

“…This study showed that, if concentrations lower than w v 0.50% / of GTA were used to crosslink the gelatin matrix, its thermal stability was significantly improved and an increase of the elastic modulus up to 100 times was achieved at ∘ C 37 . In addition, the analytical responses of crosslinked and unmodified itaconic acid based dosimeters (Mattea et al, 2015) were compared with no significant differences between each other.…”