DIAMOND AND RELATED MATERIALS, vol.156, pp.1-9, 2025 (SCI-Expanded)
In the present study, modified pencil graphite electrodes were prepared
by synthesizing a novel nanocomposite with palladium and
arginine-functionalized graphene quantum dots (Arg@GQDs) for the
electrochemical monitoring of anticancer compound mitomycin C (MC) and
double-stranded DNA (dsDNA) interaction for the first time. The
oxidation responses of both guanine in DNA and the MC drug were measured
in the same potential scanning range, and the drug-DNA interaction was
determined by the differential pulse voltammetry (DPV) method. To
improve the performance of the developed system, experimental parameters
such as dsDNA and MC concentration and their interaction times were
optimized. The surfaces obtained after the modification were
characterized using scanning electron microscopy (SEM), Energy
Dispersive X-ray Spectroscopy (EDX), Transmission Electron Microscopy
(TEM), X-ray Diffraction (XRD), Ultraviolet-Visible Spectroscopy
(UV–Vis), Fourier Transform Infrared Spectroscopy (FTIR), X-ray photon
spectroscopy (XPS), Thermogravimetric analysis (TGA) cyclic voltammetry
(CV) and electrochemical impedance spectroscopy (EIS) methods. The
developed nanocomposite-modified electrodes (Arg@GQD@Pd@PGEs) provided
higher guanine oxidation signals than PGEs. The limit of detection (LOD)
values for dsDNA immobilized on PGE and Arg@GQD@Pd@PGEs were 0.713 pg
50 μL−1 and 0.019 pg 50 μL−1, respectively.