Improvement of light stability of DHR123 radio fluorogenic nano clay gel dosimeter by incorporating a new dispersant

A tissue-equivalent three-dimensional dosimeter is being developed to verify dose distributions for radiotherapy. Recently, we have reported a nanocomposite fluorescent gel (NC-RFG) that enables readout by the fluorometry, which more sensitive than absorption method in principle. However, irradiating an excitation light information also produces dyes and not negligible low-dose irradiation range under 1 Gy. In this study, investigate new additives improve NC-RFG’s stability. We successfully suppressed light-sensitive property of NC-RFG at least 10% normal conditions adding either N-vinylpyrrolidone or pyridine as dispersant presumed break up aggregation rhodamine 123 (RD123) dihydrorhodamine (DHR123) stop photoexcited RD123 from oxidizing adjacent DHR123. provide detailed study sensitivity characteristics such rate dependence dosimeters.