Synthesis and characterization of three-dimensional mesoporous cerium oxide hollow sphere and its application as efficient electrochemical sensor for determination terazosin

Three-dimensional mesoporous CeO2 hollow sphere (M-CeO2-HS) modified glassy carbon electrode (M-CeO2-HS/GCE) was developed in this study as a very sensitive voltammetric sensor for detection of terazosin. This produced modifier was characterized by techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). There was a remarkable improvement in the electrochemical behavior relative to terazosin electro-oxidation on M-CeO2-HS/GCE surface, compared to bare GCE, in the optimized conditions of supporting electrolyte pH and casted modifier concentration. An oxidation peak was found for terazosin on modified electrode surface at the potential of about 0.57 V in phosphate buffer solution (pH=7.0). The linear dynamic range was 0.01 to 600.0 µM and the limit of detection was 1.9 nM with the aid of anodic peak of terazosin. Some advantages were reported for the modified electrode, including satisfactory reproducibility towards terazosin, potent stability, strong sensitivity and easy production. Practical applicability of the M-CeO2-HS/GCE was tested to detect the low level of terazosin in clinical and pharmaceutical formulations.