Electrochemical Determination of Doxorubicin in the Presence of Dacarbazine Using MWCNTs/ZnO Nanocomposite Modified Disposable Screen-Printed Electrode.

In the current work, the MWCNTs/ZnO nanocomposite was successfully synthesized using simple method. Then, FE-SEM, XRD, and EDX techniques were applied for morphological and structural characterization. Afterward, a sensitive voltammetric sensor based on modification of a screen-printed carbon electrode (SPCE) using MWCNTs/ZnO nanocomposite was developed for the determination of doxorubicin in the presence of dacarbazine. To evaluate the electrochemical response of the MWCNTs/ZnO/SPCE towards doxorubicin, cyclic voltammetry (CV) was applied. The MWCNTs/ZnO nanocomposite showed a significant synergistic effect on the electrochemical response of the electrode for the redox reaction of doxorubicin. Also, the MWCNTs/ZnO/SPCE demonstrated an enhanced sensing platform for the quantification of doxorubicin, obtaining a detection limit (LOD) of 0.002 µM and a sensitivity of 0.0897 µA/µM, as determined by differential pulse voltammetry (DPV) within a linear range from 0.007 to 150.0 µM. Also, the MWCNTs/ZnO nanocomposite-modified SPCE showed high electrochemical activities towards the oxidation of doxorubicin and dacarbazine with peak-potential separation of 345 mV, which is sufficient for doxorubicin determination in the presence of dacarbazine. Also, the MWCNTs/ZnO nanocomposite-modified SPCE presented reproducible and stable responses to determine doxorubicin. Finally, the developed platform demonstrated a successful performance for doxorubicin and dacarbazine determination in real samples, with recovery in the range of 97.1% to 104.0% and relative standard deviation (RSD) from 1.8% to 3.5%.