title: DNA in glasses at 77 K: high energy ionizing radiation versus UV electron ejection.
abstract: Most in the field of ionizing radiation damage to DNA in frozen aqueous solutions agree that two major types of radical ions are formed, i.e. G+/A+ and T-/C-. The main evidence stems from EPR and strand break studies. Fluid solutions exposed to laser light are known to give G+ and esolv- with low yields of single strand breaks. We have explored this contrast by photoionizing DNA solutions at 77 K, in the expectation that this would prevent the formation of esolv- and hence that the results might be similar to those for high energy radiation. They are not: the results show only the formation of G+ (or) (A+), the fate of the ejected electrons is unclear except for sodium perchlorate glasses when they react to give O-.
authors.affiliation: Department of Chemistry, Leicester University, UK.
authors.forename: M E
authors.initials: ME
authors.lastname: Malone
authors.forename: M C
authors.initials: MC
authors.lastname: Symons
authors.forename: A W
authors.initials: AW
authors.lastname: Parker
mesh_terms: D004247:DNA / Q000528:radiation effects*; D004249:DNA Damage; D004583:Electrons; D005898:Glass; D018021:Lithium Chloride; D010100:Oxygen / Q000494:pharmacology; D010472:Perchlorates; D011839:Radiation, Ionizing; D017670:Sodium Compounds; D014466:Ultraviolet Rays
chemical_list: D010472:Perchlorates; D017670:Sodium Compounds; D004247:DNA; C031068:sodium perchlorate; D018021:Lithium Chloride; D010100:Oxygen