Radiation Effects in Materials. Chapter 8: Transient Anions in Radiobiology and Radiotherapy: From Gaseous Biomolecules to Condensed Organic and Biomolecular Solids

Abstract

This chapter focuses on the fundamental processes that govern interactions of low‐energy (1–30 eV) electrons with biological systems. These interactions have been investigated in the gas phase and within complex arrangements in the condensed phase. They often lead to the formation of transient molecular anions (TMAs), and their decay by autoionization or dissociation accompanied by bond dissociation. The damage caused to biomolecules via TMAs is emphasized in all sections. Such damage, which depends on a large number of factors, including electron energy, molecular environment, and type of biomolecule, and its physical and chemical interactions with radiosensitizing agents are extensively discussed. A majority of recent findings resulting from experimental and theoretical endeavors are presented. They encompass broad research areas to elucidate important roles of TMAs in irradiated biological systems, from the molecular level to nanoscale cellular dimensions. Fundamental aspects of TMA formation are stressed in this chapter, but many practical applications in a variety of radiation‐related fields such as radiobiology and radiotherapy are addressed.