Submicromolar electrochemical sensing platform for fast Fluoxetine quantification based on Nb2CTx MXene and nitrogen-doped graphene oxide nanocomposites

A facile and novel electrochemical determination of Fluoxetine (FLX) at submicromolar concentration Niobium carbide (Nb 2 CT x ) and Nitrogen-doped Reduced Graphene Oxide (NRGO) hybridized electrodes as sensing platform is demonstrated. Herein, Niobium carbide (Nb 2 CT x ) was successfully prepared by etching Nb 2 AlC and then ultrasonically compounded with Nitrogen-doped Reduced Graphene Oxide (NRGO), to form a well-dispersed Nb 2 CT x /NRGO composite, which was modified onto a glassy carbon electrode (GCE). The morphology, structure and electrochemical property of the Nb 2 CT x /NRGO/GCE was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrocatalytic activity of the Nb 2 CT x /NRGO/GCE for FLX oxidation was studied in detail. The peak currents showed two good linear relationships (R 2 = 0.9962 and 0.9949) with FLX concentrations (1.0–10 µM and 10–100 µM) and a detection limit of 0.34 µM (S/N = 3). The sensor has good selectivity, repeatability, reproducibility and stability, and is capable of sensitively determining FLX in human serum and urine samples of clinical biological fluids. This work is believed to be of great significance and of broad interest for research on innovative MXene materials development and biomedical sensing applications.