Linearity response characterization of Polystyrene/ Graphene oxide nanocomposite as real-time dosimeter for therapeutic purposes

Introduction: In recent years, one of the emerging two dimensional (2D) carbon based nano- materials namely Graphene Oxide has been incorporated into polymeric matrices to enhance the electrical properties of the composites. The electrical conductivity of Graphene Oxide is excellently used in fabricating polymer-based sensors, energy-related systems, biotechnology, anti-statics, microwave absorbers, conductive coatings, and ionizing radiation dosimeters. The objective of this experimental work is to evaluate the linearity response of Polystyrene/Graphene oxide (0.1 wt%) nanocomposite as real-time dosimeter for therapeutic purposes. Materials and Methods: PS 1540 was supplied by Tabriz Petrochemical Company. Graphene oxide (GO) naopowder was prepared from US Nano Inc, and finally high purity toluene and DCM as the solvents were purchased from Merck Company. Solution processing has been used to prepare 0.1 wt% PS/GO nanocomposite for dosimetry purposes. A Picker-V9 60Co gamma-cell installed in the Secondary Standard Dosimetry Laboratory (SSDL) of Iran was used to irradiate the nanocomposite at various dose rates in the range of 98-159 mGy/min. Results: From the SEM images of fractured surfaces of PS/GO nanocomposite, the nano size scale of GOs nanoparticles can be observed as 140 nm. The plot of photocurrent versus dose rate for 0.1 wt% PS/GO was investigated. Results showed that the linearity was obtained in the range of 98-159 mGy/min with R2=1. The I-V measurements of the nanocomposite in a constant dose rate of 75 mGy/min at the SSD=80 cm were exhibited, in which the response was linear within the ±1000 V with R2=0.99, and also repeatability was examined for each measurement with the standard deviation less than 1%. Conclusion: In this experimental research, the linearity of Polystyrene/Graphene oxide nanocomposite as real-time dosimeter was carried out. Results showed that this nanocomposite exhibited a linear response in different dose rates ranging from 98-159 mGy/min that can be used as a real-time dosimeter utilized in therapeutic level.