Inactivation of biologically active DNA by isopropanol and formate radicals.

If OH and H radicals, produced by absorption of ionizing radiation in aqueous solutions, are scavenged with isopropanol or sodium formate, secondary radicals are formed which can inactivate phi X174 DNA. From experiments at various DNA concentrations and dose rates we were able to determine the rate constant and the inactivation efficiency of the reaction of these organic radicals with single stranded DNA.

Biological relevance of gamma-ray-induced alkali-labile sites in single-stranded Dna in aqueous solutions.

Gamma-irradiation in single-stranded phiX174 DNA in aqueous solution in the presence of oxygen produces at least two types of alkali-labile site. One is lethal and gives rise to single-strand breaks by treatment with alkali. The other is non-lethal, but is converted to lethal damage by alkali.