Electrochemical behavior of esomeprazole: Its determination at Au electrode as standard and in injection powder combined with the study of its degradation

Publication date: Available online 13 July 2019Source: Journal of Electroanalytical ChemistryAuthor(s): M. Avramov Ivić, J. Lović, S. Stevanović, N.D. Nikolić, N. Trišović, J. Lađarević, D. Vuković, S. Drmanić, A. Mladenović, M. Jadranin, S.D. Petrović, D. MijinAbstractEsomeprazole is the most effective of the proton-pump inhibitors for the acid-related diseases and at first was examined for the electroanalytical purposes. The drug standard and as a content of injection powder was investigated by cyclic voltammetry (CV) and quantitatively determined using square wave voltammetry (SWV) via its electrooxidation at Au electrode in 0.05 M NaHCO3. SWV showed a linear dependency of the anodic peak currents vs. esomeprazole standard concentrations in the range from 3.0 to 500 μg mL−1 with the values of limit of detection (LOD) and limit of quantification (LOQ): 1.4 and 4.6 μg mL−1, respectively. Using the constructed and validated calibration curve, the values of unknown esomeprazole concentrations in injection powder and in human serum spiked with standard were determined. Before the electrochemical oxidation, it was shown by atomic force microscopy (AFM) that the small esomeprazole islands formed inside holes were visible and their diameter was about 200 nm attributed to physico-chemical characteristics of esomeprazole. After the electrochemical oxidation, the morphology of esomeprazole standard on Au surface was completely changed and composed of sph...
Source: Journal of Electroanalytical Chemistry - Category: Chemistry Source Type: research