Speaker
Description
During spaceflight, the main threat to astronauts is ionising radiation, which causes DNA damage and increases the levels of reactive oxygen species, thereby affecting biological processes. The radiation-shielding materials currently used in spacecraft are often based on synthetic or inorganic components and may be heavy, brittle and difficult to produce in an isolated environment. Consequently, the greatest challenge lies in the search for biogenic, lightweight and functional anti-radiation materials.
Bacterial cellulose (BC) is produced by a symbiotic culture of bacteria and yeast (SCOBY) during the kombucha fermentation process. It is characterised by high chemical purity, ease of production and the ability to undergo surface modification.
In this study, three main experiments were conducted: in the first stage, BC was cultured in the presence of ionising radiation to assess its effect on the biosynthesis process. In the second experiment, the effect of radiation on previously isolated bacterial cellulose was investigated. Lastly, measurements of radiation attenuation coefficient were conducted for bacterial cellulose modified with tungsten salt.
Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) was used to determine changes in the chemical structure. The results obtained showed no significant differences between the control samples and the irradiated samples in either the first or the second experiment. The results suggest that the molecular structure of BC remained unaffected by ionizing radiation under the investigated conditions.
Measurements of radiation attenuation coefficient demonstrate that modification of bacterial cellulose with tungsten enhances its radiation shielding properties. The results obtained indicate that bacterial cellulose remains stable under ionizing radiation exposure, suggesting that it could be used as a matrix for lightweight radiation-shielding composites intended for space-related applications.