عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Widespread use of ionizing radiation in medicine, industry, agriculture, education and research, the increasing production of nuclear waste and nuclear incidents, has exposed humans and organisms to this radiation. Despite the benefits of ionizing radiation, these beams can cause serious damage to living systems. Hence, the need for radiation protection actions requires accurate, fast, inexpensive, and comprehensive detection and dosimetry systems. In this regard, in this paper, an electrochemical sensor based on the carboxylated multi walled carbon nanotubes-silver nano particles (MWCNTs-COOH/AgNPs) nanocomposite modified glassy carbon electrode is designed for superoxide anion detection and measurement. Also, the possibility of ionizing radiation sources detection, by measurement of superoxide which is produced during the radiolysis of aqueous environment under these radiations, is discussed. For this purpose; firstly, the surface of glassy carbon electrode modified with MWCNTs-COOH and AgNPs respectively. Ultraviolet-visible spectroscopy (UV-Vis), fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) images used to characterize the MWCNTs-COOH, AgNPs and study of the glassy carbon electrode modification with MWCNTs-COOH/AgNPs nanocomposite. Then the reduction process of superoxide produced from a solution of dimethyl sulfoxide containing potassium superoxide, on the surface of modified glassy carbon electrode studied, using cyclic voltammetry method. Also, by performing chronoamperometric studies, two linear response limits for superoxide for low concentrations (1.5 to 43 mM) and high concentrations (136 to 323 mM) and detection limit of 0.39 mM was obtained. At the end, the MWCNTs-COOH/AgNPs nanocomposite modified glassy carbon electrode was used for the detection of ionizing radiation emitted from cesium-137 and cobalt-60. The difference between electrochemical responses of the electrode, in the aqueous medium before and after the sources irradiation, attributed to the presence of superoxide and confirmed the successful performance of the sensor.