%0 Journal Article
%A Höfel, Sebastian
%A Zwicker, Felix
%A Fix, Michael K
%A Drescher, Malte
%T Towards liquid EPR dosimetry using nitroxides in aqueous solution.
%J Physics in medicine and biology
%V 69
%N 5
%@ 0031-9155
%C Bristol
%I IOP Publ.
%M DKFZ-2024-00439
%P 055026
%D 2024
%X Objective. Water-equivalent dosimeters are desirable for dosimetry in radiotherapy. The present work investigates basic characteristics of novel aqueous detector materials and presents a signal loss approach for electron paramagnetic resonance (EPR) dosimetry.Approach. The proposed principle is based on the radiation dose dependent annihilation of EPR active nitroxides (NO·) in aqueous solutions. Stable nitroxide radicals (3-Maleimido-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (MmP), 3-Carbamoyl-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (CmP)) in aqueous solutions containing dimethyl sulfoxide (DMSO) as an additive were filled in glass capillaries for irradiation and EPR readout. Radiation doses ranging from 1 to 64 Gy were applied with a clinical 6 MV flattening filter free photon beam. EPR readout was then performed with a X-band benchtop spectrometer. The dose response, temporal stability and reproducibility of the samples' EPR signal amplitudes as well as the influence of the nitroxide concentration between 10 and 160μM on the absolute signal loss were investigated using MmP. CmP was used to examine the dependence of the dose response on DMSO concentration between 0 and 10 vol
%K Electron Spin Resonance Spectroscopy: methods
%K Reproducibility of Results
%K Dimethyl Sulfoxide
%K Radiometry: methods
%K Water
%K Nitrogen Oxides
%K EPR dosimetry (Other)
%K dimethyl sulfoxide (Other)
%K nitroxide (Other)
%K radiotherapy (Other)
%K water equivalence (Other)
%K nitroxyl (NLM Chemicals)
%K Dimethyl Sulfoxide (NLM Chemicals)
%K Water (NLM Chemicals)
%K Nitrogen Oxides (NLM Chemicals)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:38306975
%R 10.1088/1361-6560/ad25c4
%U https://inrepo02.dkfz.de/record/288730