Study of the formulation optimization and reusability of a MAGAT gel dosimeter
| Autor: | Jéssica Caroline Lizar, Fred Muller dos Santos, Leandro Federiche Borges, Thiago Dias Resende, Juliana Fernandes Pavoni |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Materials science
food.ingredient Biophysics General Physics and Astronomy Gel dosimetry Gelatin 030218 nuclear medicine & medical imaging 03 medical and health sciences chemistry.chemical_compound Organophosphorus Compounds 0302 clinical medicine food Equipment Reuse Radiology Nuclear Medicine and imaging Hydroxymethyl Irradiation Dosimeter Radiation Dosimeters Phosphonium chloride Radiochemistry General Medicine Magnetic Resonance Imaging Methacrylic acid chemistry 030220 oncology & carcinogenesis DOSÍMETROS Dose rate Gels |
| Zdroj: | Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual) Universidade de São Paulo (USP) instacron:USP |
| ISSN: | 1120-1797 |
| DOI: | 10.1016/j.ejmp.2019.05.018 |
| Popis: | Purpose This study aims to optimize the formulation of a methacrylic acid gelatine and tetrakis (hydroxymethyl) phosphonium chloride (MAGAT) gel dosimeter to achieve acceptable dosimetric characteristics and the lowest final costs. This study also evaluates the reusability of the dosimeter. Methods The MAGAT gel dosimeter formulation was optimized. Tetrakis (hydroxymethyl) phosphonium chloride (THPC) concentrations (2, 5, 8, 10, 20, and 65 mM), methacrylic acid (MA) concentrations (2.0, 2.5, 3.0, 3.5, and 4.0% w/w) and gelatin concentrations (4.36, 6.45, 8.36, and 10.45% w/w) were evaluated to provide an adequate dosimetric response. The final dosimeter formulation linearity and dose rate dependence were evaluated. The reutilization methodology of the optimized gel formulation, but containing 2 mM of THPC, which was previously irradiated with a dose of 2 Gy, is also presented. Results The optimized mass concentration of the dosimeter consists of 88.60% deionized water, 8.36% gelatin, 3.00% of MA and 0.04% THPC (5 mM). It presents a linear response for doses up to 10 Gy with a 1.16 Gy−1 s−1 sensitivity. A maximum sensitivity variation of less than 4.0% was found when varying the dose rate of the radiation beams from 300 to 500 cGy/min. It was possible to reuse the dosimeter, however the sensitivity decreased by 15% from the first to the second irradiation. Conclusions A low-cost MAGAT gel dosimeter with optimized formulation that responds to radiation in a dose range of 0 to 10 Gy with small dose-rate dependence is presented. The MAGAT gel can be reused after a 2 Gy irradiation. |
| Databáze: | OpenAIRE |
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