Phenol compounds as a New Materials for EPR dosimetry in radiation therapy

Among the various dosimetric techniques used for characterizing the radiation beams used in radiation therapy, the Electron Paramagnetic Resonance (EPR) arouses increasing interest for applications in various therapy procedures. When a compound is irradiated with ionizing radiations free radicals are produced and their concentration is proportional to the absorbed dose. This allows for dosi-metric measurements through EPR technique which is able to quantitatively de-termine the radical concentration. Our research group has started an investigation of the EPR response of some phenols compounds for possible dosimetric applications. In this work we report the EPR investigation of IRGANOX 1076 pellets and thin films exposed to various type of radiation beams. Phenols are compounds possessing a benzene ring attached to a OH group. After irradiation the final product is a stable phenoxy radical. The stability of such radi-cal can be improved by adding other alkyl chains which can be attached to the benzene ring. In particular, the phenol octadecyl3(3,5ditertbutyl4hydroxyphenyl) propionate (IRGANOX 1076) gave interesting results.