Abstract: Polymer gel dosimeters based on radiation-induced polymerization of N-(Isobutoxymethyl) acrylamide (NIBMA) polymer gels in normal atmospheric condition (NIBMAGAT) have been synthesized and studied as a new composition of polymer gel dosimeters for radiotherapy treatment planning. The dosimeters were irradiated with at absorbed doses up to 30 Gy and no change in dose response was observed even after using repeatedly for eight times. The novel composition shows no change in the relaxation rate or absorbance of the gel dosimeters up to 144 hours. Dose response of NIBMAGAT gel dosimeters increases with increase of monomer concentration. The relaxation rate of NIBMAGAT gel increases with increase of THPC concentration from 2.5 to 5 mM, but the dose response is not affected with increase of THPC concentration from 5 to 20 mM. The results show that the dose sensitivity increases significantly with increase of glycerol concentration up to ?30% within gel dosimeters.

Abstract: Normal N-(Hydroxymethyl) acrylamide (PNHMAG) and normoxic N-(Hydroxymethyl) acrylamide (NHMAGAT) polymer gel dosimeters with low toxicity and low cost are invented for radiation treatment planning. A high dose response was displayed in this invention using nuclear magnetic resonance (NMR) and spectrophotometer methods. The response of both types of gels showed an independence of dose rate and radiation energy and a high degree of stability after irradiation.

Abstract: Novel normoxic N-(Hydroxymethyl) acrylamide (NHMAGAT) polymer gel dosimeters for MRI scanning are introduced for radiotherapy planning system. The composition of the NHMAGAT polymer gel and method of making the NHMAGAT polymer gel dosimeter are disclosed. The dosimeters are irradiated with Varian Rapid Arc linear systems at different absorbed doses. The results show that the percent depth dose and 2D plan dose distribution of NHMAGAT polymer gel dosimeters are in a good agreement with the ionization chamber measurements and CT planned dose distribution, respectively.