Introduction of Ketamine as a G-Quadruplex-Binding Ligand Using Platinum Nanoparticle Modified Carbon Paste Electrode

We designed an electrochemical platform by modifying a carbon paste electrode (CPE) with platinum nanoparticles to study the interaction between ketamine and the G-quadruplex structure of human telomeric DNA (G(4)HTD). The drug ketamine (Kt) was used as the model ligand and its ability for stabilizing the G-quadruplex structure was examined. The modified CPE (NPtCPE) was characterized by differential pulse voltammetry (DPV) and atomic force microscopy (AFM). The interaction of Kt with G(4)HTD was studied by DPV and the DPV current decreased with increasing Kt concentration. The results from UV-vis and circular dichroism (CD) spectroscopy showed a prominent intercalation mode between G(4)HTD and Kt.