Polymer gel dosimeters of different formulations were manufactured from different monomers of acrylamide, acrylic acid, methacrylic acid, 1-vinyl-2-pyrrolidinone, 2-hydroxyethyl methacrylate and 2-hydroxyethyl acrylate. Gelatin and agarose were used as the gelling agents and N,N '-methylene-bis-acrylamide was used as a co-monomer in each polymer gel dosimeter. The T₂ dependence of each dosimeter was analysed using a model of fast exchange of magnetization. The influence of the half-dose and the apparent T₂ of the polymer proton pool on the dose resolution (DΔp) were examined. Comparisons are made with the commonly employed R₂–dose sensitivity. Differences exist suggesting that experiments reported in the literature using what were thought to be more optimal dosimeters may not actually be so. Based on DΔp of each formulation, conclusions are drawn on the optimal formulation required for a specific range of absorbed doses. In addition, information about the extent of polymerization of the monomers used along with some characteristics of the polymer network formed are reported. The influence of the concentration of monomers and gelling agent was subsequently evaluated using a model of fast exchange of magnetization. Based on these calculations, further improvement in DΔp can be expected.
Lepage, M., Jayasakera, P. M., Bäck, S. Å. J., & Baldock, C. (2001). Dose resolution optimization of polymer gel dosimeters using different monomers. Physics in Medicine and Biology, 46(10), 2665-2680. https://doi.org/10.1088/0031-9155/46/10/310