In the first section of this study, the mode of double strain deoxyribonucleic acid (dsDNA) and curcumin binding was investigated by differential pulse voltammetry, UV-VIS spectroscopy and molecular docking. The binding constant was calculated by molecular docking (K = 4.9×10 4 ). Moreover, minor groove was predicted based on three methods of dsDNA and curcumin binding. Additionally, the temperature effect was studied by cyclic voltammetry on the dsDNA and curcumin binding and the binding constants were 3.6×10 4 in 25°C, 4.3×10 4 in 30°C, 5.7×10 4 in 35°C, 7.2×10 4 in 40°C, 9.9×10 4 in 45°C. The binding constant was increased by elevating temperature. In the second part of this study, azobenzene-rGo-CNT electrocatalyst was synthesized, and characterized by FT-IR, UV-VIS, XRD, SEM, TEM, AFM, EDS, element mapping and BET. The electrochemical sensor base on the GC electrode was modified afterwards and square wave voltammetry was used for determining curcumin. The efficiency of the catalyst was studied by cyclic voltammetry and electrochemical impedance. Subsequently, various effective parameters on the sensitivity and selectivity of the method including pH, potential, preconcentration time, and device parameters were optimized. The amount of electron transfer constant as well as electron rate constant were respectively calculated by Laviron equation as 0.55 and 0.32 s -1 . The linear ranges of the sensor were 8×10 -9 -2×10 -6 and 2×10 -6 -1×10 -5 molar, the limit of detection, repeatability and reproducibility were 3×10 -9 molar, 2.0% and 3.6% respectively. Then, the selectivity of this method for determining curcumin in the presence of different interference species was studied. Finally, prosperously designed electrode for determining curcumin was applied in the real samples including plasma, urine, and tablet.
