Application of disposable biosensor for nivolumab–DNA interaction using pencil graphite electrode

Abstract: In this study, the interaction of the anticancer drug Nivolumab (NIVO) with dsDNA was investigated using differential pulse (DPV) technique by monitoring the changes in the oxidation signal of adenine and guanine bases on PG electrode. Surface characterization of the PG (pencil graphite) electrode was carried out using cyclic voltammetry, electrochemical impedance spectrometry techniques and scanning electron microscope, Energy Dispersive X-ray. DPV parameters, the effect of pH on the electrode surface, stirring speed, dsDNA immobilization time, immobilized dsDNA concentrations, NaCl concentration, NIVO concentration interacting with dsDNA were optimized with PG electrode. With the determined parameters, NIVO–dsDNA interaction in PBS (pH 3.0) supporting electrolyte solution was elucidated. In the NIVO–dsDNA interaction using UV technique, the K binding constant and free energy of binding value was found to be 8.93 × 104 and 6.754 kcal mol–1, respectively. It was determined that the data obtained by electrochemical method were in parallel with the data obtained by spectrometric method. The results obtained electrochemically with high sensitivity, low cost, fast, simple, low detection limit will be the first example of NIVO–dsDNA interaction using PG electrode.