The synthesis and characterization of 3D mesoporous CeO2 hollow spheres as a modifier for the simultaneous determination of amlodipine, hydrochlorothiazide and valsartan
Herein, mesoporous CeO2 hollow spheres (M-CeO2-HSs) with a three-dimensional configuration were synthesized via a facile strategy. The morphology and structure of the three-dimensional M-CeO2-HSs were characterized via XRD, SEM, and EDX. In order to demonstrate their practical application, the as-prepared M-CeO2-HSs were applied as a modifier, which exhibited high catalytic activity for the simultaneous detection of amlodipine (AML), hydrochlorothiazide (HCTZ) and valsartan (VAL). Furthermore, a modified electrode was fabricated and investigated via electrochemical impedance spectroscopy (EIS). An unmodified GCE and the M-CeO2-HS-modified glassy carbon electrode (M-CeO2-HS/GCE) were utilized to assess their electrochemical behaviors towards AML, HCTZ and VAL. It was observed that the electrochemical responses of M-CeO2-HS/GCE towards these analytes were remarkably enhanced. M-CeO2-HS/GCE exhibited satisfactory responses for AML, HCTZ and VAL with detection limits of 7.9 nmol L−1, 3.8 nmol L−1 and 5.4 nmol L−1 (S/N = 5), respectively. The diffusion coefficient (D) and heterogeneous rate constant (kh) were detected for the oxidation of AML, HCTZ and VAL on the surface of the modified electrode. In addition, the analytical application of M-CeO2-HS/GCE was investigated, which demonstrated acceptable results for the simultaneous detection of AML, HCTZ and VAL in real specimens.