A sensitive electrochemical sensor for detection of methyltestosterone as a doping agent in sports by CeO2/CNTs nanocomposite

The goal of the current study was to create a sensitive electrochemical sensor using a modified glassy carbon electrode and a CeO2/CNTs nanocomposite for the detection of methyltestosterone (MT) as a doping substance in sports (GCE). The CeO2/CNTs nanocomposite was prepared by the solvothermal method. FE-SEM and XRD structural and morphological analyses showed that the CeO2 nanoparticles were successfully anchored to the CNT matrix. Electrochemical experiments showed that the signal for MT electrochemical sensors can be am-plified by attaching CeO2 nanoparticles to tube structures of linked CNTs with hierarchical pores and large effective surface areas as multiple electroactive centers. Results showed excellent selectivity, a sensitivity of 8.5992 mu A/mu g mL-1, a broad, stable linear range of 0-10 mu g/mL, and a very low detection limit of 0.3 ng/mL at CeO2/CNTs/GCE for MT determination. The accuracy and the applicability of CeO2/CNTs/GCE as an MT sensor in real human blood serum samples from athlete volunteers were examined. Suitable recovery values (94.50-98.00 %) and acceptable values of RSD (3.97-5.03 %) were obtained, which qualify the designed sensor for application in clinical and biological samples.