Study of synthetic oligonucleotides containing guanine by circular dichroism spectroscopy and voltammetry on a pyrolytic graphite electrode

The possibility to study DNA quadruplex structures using voltammetric analysis of DNA hexamers was investigated using a pyrolytic graphite electrode in an acetate buffer (pH = 5.0). We have tested the influence of the hexamer sequence and DNA concentration their anodic oxidation. To verify the G quadruplex formation, or lack thereof, circular dichroism spectroscopy was used. Our results suggest that, on the pyrolytic graphite electrode, the guanine oxidation signals are not influenced by formation of G the quadruplex. Instead, the shape of the G oxidation multiple peak can be related to the primary structure of the oligonucleotide.