Electrochemical
Discrimination between G‑Quadruplex
and Duplex DNA
- Publication date
- Publisher
Abstract
Analytical tools enabling the discrimination
between duplex DNA
and G-quadruplex DNA are necessary to unravel the biological function(s)
of G-quadruplexes. A methodology relying on the electrochemical response
of the electroactive hexaammineruthenium(III) cation at DNA-modified
surfaces is presented. A characteristic voltammetric peak is evidenced
for all the investigated G-quadruplex sequences, encompassing various
types of folding and numbers of quartets. In contrast, no such peak
is detected for dsDNA sequences. The occurrence of the voltammetric
peak is the consequence of a strong association between the hexaammineruthenium
ligand and the surface-immobilized G-quadruplexes. The peak potential
points to a significant contribution of nonelectrostatic interactions
between the electroactive ligand and G-quadruplexes. The very good
efficiency of the discrimination methodology is demonstrated by comparing
a G-quadruplex and its corresponding duplex