An international research team which includes DTU has contributed to a greater understanding of how ionizing radiation harms cells, and how we can protect ourselves against it.
Understanding how ionizing radiation (including UV and radioactive radiation) interacts with water and forms radicals has a key bearing on such diverse areas as nuclear power, aerospace, and X-ray examinations. Not least because these radicals can diffuse through an organism and damage virtually any macromolecule, including DNA, RNA, and proteins.
To understand this proton transmission reaction, for example in the human body, it is necessary to be able to observe and document some of the quickest chemical reactions that exist.
In a worldwide collaboration led by the Argonne National Laboratory, a multidisciplinary science and engineering research centre under the U.S. Department of Energy, and with the participation of DTU, researchers have for the first time witnessed the proton transfer reaction after the ionization of liquid water.
The observation was made using an ultra-fast X-ray electron laser, and was analysed using software that was developed with the participation of PhD student Khadijeh Khalili from DTU.
“In collaboration with researchers from several countries, we managed to successfully develop a piece of software that enables us to translate the observations into a kind of ‘film’ of so-called radicals being created, even though this is a process that takes place within a billionth of a second,” explains Khalili, who works on a daily basis at the ERC centre Solar Energy Enabled for the World by High-resolution Imaging (SEEWHI) at DTU.
DTU professor Jens Wenzel Andreasen, who runs SEEWHI, is thrilled with the result, and welcomes the fact that it stems from cooperation not just between different countries, but also across various research areas:
“DTU’s contribution to observing the ultra-fast radicals is rooted in the methods which SEEWHI has developed to study cargo transfer in molecules which are used for organic solar cells. This is an outstanding example of how groundbreaking technology can often be applied across research disciplines and areas.”
By understanding the timescale for the formation of the aggressive group of so-called hydroxyl radicals, and thereby gain a deeper understanding of radiolysis in water, it may eventually be possible to develop strategies to suppress this central process in the formation of radiation damage.