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Updated: Jul 30, 2026

Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
Temperature dependence of polymer-gel dosimeter nuclear magnetic resonance response
V Spevacek1, J Novotny, P Dvorak
1Czech Technical University in Prague, Faculty of Nuclear Science and Physical Engineering, Department of Dosimetry and Application of Ionizing Radiation, Brehova 7, 110 00 Prague 1, The Czech Republic.
Abstract:
The purpose of this study was to find a physical-mathematical description capable to correct a polymer-gel dosimeter relaxation rate R2-dose response for different temperatures. Four different modifications of polymer-gel dosimeters were used in this study. Samples with polymer-gel dosimeter in glass test vessels were homogeneously irradiated by 60Co gamma photons. A multi-echo sequence with 16 equidistant echoes was used for evaluation of irradiated polymer-gel dosimeters. The sequence parameters were as follows: TR 2000 ms, TE 22.5-360.0 ms, slice thickness 5 mm, FOV 255 mm, one acquisition. The proposed description recommends to subtract R2 response of the nonirradiated dosimeter from the total R2-dose response. The relaxation rate for the irradiated dosimeter can be expressed as a function of temperature and dose. The temperature dependence has an exponential behavior in the measured range. The proposed description allows to correct the measured NMR R2-dose responses for different temperatures.
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