Formation of spectral intermediate G-C and A-T anion complex in duplex DNA studied by pulse radiolysis.

The dynamics of electron adducts of 2'-deoxynucleotides and oligonucelotides (ODNs) were measured spectroscopically by nanosecond pulse radiolysis. The radical anions of the nucleotides were produced within 10 ns by the reaction of hydrated electrons (e(aq)(-)) and were protonated to form the corresponding neutral radicals. At pH 7.

Effect of base sequence and deprotonation of Guanine cation radical in DNA.

The deprotonation of guanine cation radical (G+*) in oligonucleotides (ODNs) was measured spectroscopically by nanosecond pulse radiolysis. The G+* in ODN, produced by oxidation with SO4-*, deprotonates to form the neutral G radical (G(-H)*). In experiments using 5-substituted cytosine-modified ODN, substitution of the cytosine C5 hydrogen by a methyl group increased the rate constant of deprotonation, whereas replacement by bromine decreased the rate constant.

Photogenerated hole mobility in DNA measured by time-resolved microwave conductivity.

We report the first direct observation of charge transport dynamics using time-resolved microwave conductivity and transient absorption spectroscopy techniques on the photolysis of an anthraquinone-bound DNA complex.