Study on characteristic of Fricke xylenol gel dosimeter: application for dose evaluation in radiotherapy

Accurate assessment of the radiation absorbed dose delivered to a tumor and different organs is a potentially importance issue in clinical radiotherapy. The aim of this study is to evaluate the effectiveness of the Fricke Xylenol Gel dosimeter (FXG) to the gamma radiation from Co-60. With this aim, the dose response of FXG and its behavior have been investigated. The sensitivity and accuracy of FXG were validated by irradiating FXG with the gamma radiation at 1-200 Gy. To evaluate the long- and short-term consistency and reproducibility of FXG, the optical density was measured at 24, 48 and 120 h after irradiation. Light absorbance spectra were analyzed from 350-700 nm. Spectrophotometric measurement of FXG demonstrated the linearity up to 30 Gy, and then gradually reached a plateau. FXG showed a good stability over a period of 120 h after exposure to gamma radiation. FXG showed a high reproducibility which is in comparable to that of obtained from the ionization chamber. The FXG showed high accuracy, sensitivity and reproducibility, thus enabling determination of absorbed dose from the external beam radiotherapy.