Electrochemical Sensing Platform Based on the Modification of Carbon-Ceramic Electrode with Bimetallic Fe/Mn-MOF Applied in the Determination of Nifedipine in Human Serum Samples

Abstract

Background: Nifedipine, known as a calcium channel blocker, is widely used for the treatment of cardiovascular diseases such as hypertension and angina pectoris. However, its high doses are toxic and may result in a heartbeat, nausea, vomiting, etc. Methods: In the present research, the bimetallic Fe/Mn-MOF modified carbon-ceramic electrode (CCE) was used for studying the electrochemical behavior and determination of nifedipine. The presence of Fe/Mn-MOF on the surface of the CCE as an efficient modifier caused an increase in the current density of nifedipine oxidation. In this way, optimization of some effective parameters consisting of buffer type, pH, modifier concentration, etc. was successfully performed. Moreover, other analytical parameters including reproducibility, repeatability, stability, and selectivity were investigated. Results: The relative standard deviation (RSD) of peak current was 3.2 % for 10 µmol.L-1 nifedipine. Meantime, the linear range of 1-200 µmol.L-1. Additionally, limit of detection (LOD) and limit of quantification were obtained 0.24 μmol.L-1 and 0.82 µmol.L-1 respectively. The results showed that the modified electrode has a good electro-oxidation capability for nifedipine. Finally, for investigating the accuracy of the fabricated sensing assay, the determination of nifedipine in drug and human serum samples was performed. The recoveries and the related RSDs% were obtained 96.4-102% and 2.2-3.6% respectively. Conclusion: This modified electrode exhibited appropriate stability, low cost, simple preparation, fast response time, high repeatability, and good sensitivity. The obtained results clearly demonstrate the applicability of the proposed sensing assay in various matrix effects which does not affect the electrochemical response.