Abstract：
This work aims to improve the post stabilty of reusable potassium iodide hydrogel dosimter. A reusable and low-cost radiochromic dosimeter containing a gel matrix of polyvinyl alcohol, potassium iodide dye, froctose as reducing agent and glutaraldehyde as cross-linking agent was developed for dose calibration in radiotherapy. The gel samples were exposed to different absorbed doses using a medical linear acceleration. UV-vis Spectrophotometry was utilized to investigate the changes in optical-properties of irradiated gels with regard to peak wavelength of 353 nm. The stability of the gel (one of the most limitation of using this dosimeter) was improved significantly by the addition of certain concentrations of dimethyl sulfoxide. The two-dimensional optical imaging system of charge-coupled-device (CCD) camera with a uniform RGB light-emitting-diode (LED) array source was used for diffusion coefficient purpose using two dimensional gel template. The value of diffusion coefficient reported is significant and highly reduced compared with other dosimeters reported in the literatures. Moreover, heating the improved gels to certain temperatures results in resetting their optical properties, which makes it possible to reuse for multiple times.
摘要：
这项工作旨在提高可重复使用的碘化钾水凝胶剂的后稳定性。一种可重复使用且低成本的放射变色剂量计，其中包含聚乙烯醇的凝胶基质，碘化钾染料，开发了氟乳糖作为还原剂和戊二醛作为交联剂用于放射治疗剂量校准。使用医用线性加速将凝胶样品暴露于不同的吸收剂量。UV-Vis分光光度法用于研究辐照凝胶的光学性质相对于353nm的峰值波长的变化。通过添加一定浓度的二甲基亚砜，凝胶的稳定性（使用该剂量计的最大限制之一）得到了显着改善。具有均匀RGB发光二极管（LED）阵列源的电荷耦合器件（CCD）相机的二维光学成像系统使用二维凝胶模板用于扩散系数目的。与文献中报道的其他剂量计相比，报道的扩散系数的值是显着的并且大大降低。此外，将改进的凝胶加热到一定的温度导致其光学性能的重置，这使得可以重复使用多次。
