Enhancement in dose sensitivity of polymer gel dosimeters composed of radiation-crosslinked gel matrix and less toxic monomers

A Hiroki,S Yamashita,M Taguchi

doi:10.1088/1742-6596/573/1/012028

Abstract

Polymer gel dosimeters based on radiation-crosslinked hydroxypropyl cellulose gel were prepared, which comprised 2-hydroxyethyl methacrylate (HEMA) and polyethylene glycol #400 dimethacrylate (9G) as less toxic monomers and tetrakis (hydroxymethyl) phosphonium chloride (THPC) as an antioxidant. The dosimeters exposed to 60Co γ-rays became cloudy at only 1 Gy. The irradiated dosimeters were optically analyzed by using a UV- vis spectrophotometer to evaluate dose response. Absorbance of the dosimeters linearly increased in the dose range from 0 to 10 Gy, in which dose sensitivity increased with increasing 9G concentration. The dose sensitivity of the dosimeters with 2 wt% HEMA and 3 wt% 9G was also enhanced by increment in THPC.

Highlights

Most of the polymer gel dosimeters [1] utilize gelatin and either methacrylic acid or acrylamide [2, 3]
This study aims to enhance in dose sensitivity of polymer gel dosimeters based on a radiationcrosslinked gel matrix
It is clearly seen that the cloudiness of the polymer gel dosimeters prepared by using a monomer solution with 2 wt% hydroxyethyl methacrylate (HEMA), 3 wt% 9G, and 0.16 wt% tetrakis (hydroxymethyl) phosphonium chloride (THPC) increased with the increasing dose

Summary

Introduction

Most of the polymer gel dosimeters [1] utilize gelatin and either methacrylic acid or acrylamide [2, 3] Since both monomers are considered harmful, new recipes for polymer gel dosimeters using less toxic monomer, N-isopropyl acrylamide (NIPAM), have been reported [4]. Hiroki et al reported that the dose sensitivity of dosimeters based on gellan gum and less toxic monomers increased with the initial monomer concentration [7]. In these gel dosimeters, the solubility and compatibility of the chemicals become a hindrance to the increasing dose sensitivity as well as the preparation of transparent polymer gel dosimeters

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Methods

Results