FORMATION OF 8-HYDROXYDEOXYGUANOSINE FROM DEOXYGUANOSINE BY FE2+/ASCORBIC ACID/EDTA/H2O2 SYSTEM

8-Hydroxydeoxyguanosine (8-OH-dG) was formed in deoxyguanosine (dG) solution by the addition of Fe2+, ascorbic acid (AscA), EDTA, and H2O2, and was then detected by ECD after separation by HPLC. 8-OH-dG was not formed in significant amounts when either Fe2+, AscA, or H2O2 was added separately, or when two of these were added in combination. When Fe2+, AscA, and H2O2 were added simultaneously, however, 0.87 nmol of 8-OH-dG was formed from 2.5 mu mol of dG. And the addition of EDTA (in the same concentration as Fe2+) to the Fe2+/AscA/H2O2 system caused a remarkable increase in the amount of 8-OH-dG formed (up to 2.89 nmol from 2.5 mu mol of dG). The amount of 8-OH-dG formed increased as the concentration of AscA increased up to I mM (the same concentration as Fe2+). However, higher concentrations of AscA inhibited the formation of 8-OH-dG.