Differences in fundamental reaction mechanisms between high and low-LET in recent advancements and applications of ionizing radiation

Abstract

International audienceRecent applications of high-LET radiation include boron neutron capture therapy. UV treatment of electron-irradiated UHMWPE impedes degradation caused by allyl radicals. Radiation synthesis of PVP nanogels above 55 1C leads to intra-molecular crosslinking. PCBs in contaminated sediments can be dechlorinated by reactions with hydrated electrons. a b s t r a c t Differences among the mechanisms of energy deposition by high-linear energy transfer (LET) radiation, consisting of neutrons, protons, alpha particles, and heavy ions on one hand, and low-LET radiation, exemplified by electron beam and gamma radiation on the other, are utilized in the selection of types of radiation used for specific applications. Thus, high-LET radiation is used for modification of carbon nanotubes, ion track grafting, and the synthesis of membranes and nanowires, as well as for characterization of materials by means of neutron scattering. Recent applications of low-LET irradiation include minimization of radiolytic degradation upon sterilization of ultra-high molecular weight polyethylene (UHMWPE), radiolytic synthesis of nanogels for drug delivery systems, grafting of polymers in the synthesis of adsorbents for uranium from seawater, and reductive remediation of PCBs

Gamma Radiation Synthesis of Colloidal Silver Nanoparticles

“…Silver nanoparticles are formed either by combining these clusters or by absorbing a neutral Ag 0 atom. (2) On the other hand, hydroxyl radicals (OH ! ) resulting from the water radiolysis process have the ability to oxidize either ions or atoms to higher oxidation states.…”

“…The current applications of ionizing radiation and their connection with nanotechnology represent a research area that has gained special attention in recent years [1][2][3][4]. The revolutionary development of science and engineering has enabled the synthesis of nano-sized materials in order to take advantage of their unique properties that differ significantly from those of the individual atoms [5,6].…”